CN219251391U

CN219251391U - Catheter pump

Info

Publication number: CN219251391U
Application number: CN202222863344.8U
Authority: CN
Inventors: 张家良; 付建新; 刘刚
Original assignee: Magassist Inc
Current assignee: Magassist Inc
Priority date: 2021-10-29
Filing date: 2022-10-28
Publication date: 2023-06-27
Anticipated expiration: 2032-10-28
Also published as: CN219251397U; CN114225213B; CN219251398U; CN114225213A; CN219251396U; CN217960999U; WO2023070515A1; CN116059524A; CN217960998U

Abstract

The present disclosure provides a catheter pump for assisting in the failure of the heart, which is capable of significantly reducing adverse events of blood damage. Wherein, a catheter pump includes: a motor; a catheter connected proximally to the motor; a drive shaft driven by the motor; a pump body, comprising: a pump housing connected to the distal end of the catheter, an impeller received within the pump housing; the pump housing includes: a stent, a coating partially covering the stent; the proximal end bearing is arranged at the proximal end of the bracket; a distal bearing disposed at a distal end of the bracket; wherein the drive shaft comprises: a first shaft rotatably penetrating the guide pipe and a second shaft connected with the impeller; the second shaft has a stiffness greater than the first shaft; the proximal end of the first shaft is in transmission connection with the rotating shaft of the motor, and the distal end of the first shaft is connected with the proximal end of the second shaft; the proximal end and the distal end of the second shaft are respectively penetrated in the proximal end bearing and the distal end bearing.

Description

Catheter pump

Cross-reference to related references

The present application claims priority from PCT International application No. PCT/CN2021/127377 entitled "catheter Pump" filed on Jade 10, 2021 and 29, the entire contents of which are incorporated herein by reference.

Technical Field

The utility model relates to the field of medical equipment, in particular to heart auxiliary use equipment, and more particularly relates to an interventional catheter pump and a pump body thereof.

Background

Heart failure is a life threatening disease that once advanced, has a annual mortality rate of about 75%. Given the limited number of heart donors with advanced heart failure, ventricular assist device technology has become a viable therapeutic or alternative choice between lifting subjects and transplant surgery. Adverse events caused by current technology still limit the use of ventricular assist devices for the treatment of critically ill subjects.

Among these adverse events are those associated with blood damage, such as hemolytic neurological events, strokes, and intra-pump thrombosis, accounting for 20% of the incidence, with hemolysis and thromboses being primarily due to excessive physiological stress and flow stagnation in rotary blood pumps. Although the blood compatibility can be improved by hydraulic design optimization, for a rotary blood pump with blood immersed bearings, direct contact between the rotary and stationary components is unavoidable and it is difficult to provide substantial improvement in adverse events of blood damage.

Disclosure of Invention

In view of the above-mentioned shortcomings, it is an object of the present utility model to provide a catheter pump for assisting in the failure of the heart to significantly reduce adverse events of blood damage.

In order to achieve the above purpose, the utility model adopts the following technical scheme:

a catheter pump comprising:

a motor;

a catheter connected proximally to the motor;

a drive shaft driven by the motor;

a pump body, comprising: a pump housing connected to the distal end of the catheter, an impeller received within the pump housing; the pump housing includes: a stent, a coating partially covering the stent;

the proximal end bearing is arranged at the proximal end of the bracket;

a distal bearing disposed at a distal end of the bracket;

wherein the drive shaft comprises: a first shaft rotatably penetrating the guide pipe and a second shaft connected with the impeller; the second shaft has a stiffness greater than the first shaft; the proximal end of the first shaft is in transmission connection with the rotating shaft of the motor, and the distal end of the first shaft is connected with the proximal end of the second shaft; the proximal end and the distal end of the second shaft are respectively penetrated in the proximal end bearing and the distal end bearing.

Preferably, the proximal end of the bracket is provided with a proximal bearing chamber; the proximal bearing supports the proximal end of the second shaft within the proximal bearing chamber.

Preferably, the proximal end of the bracket is provided with a connecting secondary pipe connected with the distal end of the catheter; the connecting secondary pipe forms the proximal bearing chamber, and the proximal bearing is arranged in the connecting secondary pipe.

Preferably, the proximal end of the bracket is provided with a connecting secondary pipe; the proximal bearing chamber is connected with the distal end of the catheter; the proximal bearing chamber is fixedly sleeved in the connecting secondary pipe.

Preferably, the connecting secondary pipe and the bracket are of an integral structure.

Preferably, the proximal end of the bracket is also provided with a limiting piece which is axially arranged at intervals with the proximal bearing; a stop piece is fixedly arranged on the driving shaft; the stop piece is located between the proximal bearing and the limiting piece and is axially limited by the proximal bearing and the limiting piece.

Preferably, the stop is another proximal bearing; or the limiting piece is a retainer ring fixedly arranged in the proximal bearing chamber.

Preferably, the stop is another proximal bearing. At this point, the stop is located between the two proximal bearings.

Preferably, the limiting piece is a retainer ring fixedly arranged in the proximal bearing chamber; the gap width between the retainer ring and the drive shaft is greater than the gap width between the proximal bearing and the drive shaft.

Preferably, the collar is located proximal to the proximal bearing.

Preferably, the stop piece is a stop ring fixedly sleeved on the driving shaft.

Preferably, the proximal end of the stopper is in contact limit with the stopper, and the distal end of the stopper is in contact limit with the proximal bearing. The stop member is clamped with the proximal bearing without play, so that the second shaft is fixed.

Preferably, the stopper is axially movably provided between the proximal bearing and the stopper, which limit the axial movement range of the stopper.

Preferably, the first shaft is a braided structure.

Preferably, the first shaft comprises a plurality of braiding layers sleeved layer by layer; each layer of the braiding layer is formed by spiral winding wires.

Preferably, the directions of rotation (the directions of helical extension of the helical windings) of adjacent two braid layers are opposite.

Preferably, the first shaft is provided with a spiral structure on its outer wall; the direction of rotation of the spiral structure is opposite to the direction of rotation of the drive shaft. Specifically, the helical structure is left-handed threads in the case of clockwise rotation of the first shaft, or right-handed threads in the case of counterclockwise rotation of the first shaft, as viewed from the proximal end to the distal end.

Preferably, the helical structure is a helical groove or a helical protrusion. Preferably, the helical structure is formed by braiding.

Preferably, the rotation direction of the outermost braid is opposite to the rotation direction of the drive shaft. Specifically, when the drive shaft rotates clockwise, the braiding layer of the outermost layer has a left-handed spiral structure, or when the drive shaft rotates counterclockwise, the braiding layer of the outermost layer has a right-handed spiral structure, as viewed from the proximal end to the distal end.

Preferably, when the stop member contacts and limits the proximal bearing (the second proximal bearing), the shaft connection portion is located near the distal end face of the limiting member (the first proximal bearing or the retainer ring). At this time, the stopper is located at the far dead point position.

Preferably, the proximal end of the second shaft forms the shaft connection by reducing the diameter; the distal end of the shaft connecting part is provided with a diameter-reducing step; when the stop piece is in contact limit with the proximal end bearing (the second proximal end bearing), the diameter-reducing step is positioned near the distal end face of the limit piece.

Preferably, when the stopper is in contact with the proximal bearing (second proximal bearing) for limiting, the axial distance between the diameter-reducing step and the distal end face of the first shaft is greater than the axial distance between the stopper and the limiting member.

Preferably, when the stop piece is in contact with and limited by the limiting piece, a certain distance is formed between the diameter-reducing step and the distal end face of the first shaft. Preferably, the radial thickness of the diameter-reducing step is smaller than the wall thickness of the conduit wall of the mating channel.

Preferably, the inner wall of the distal end of the first shaft forms the mating channel by expanding in diameter; the proximal end of the matching channel is provided with an expanding step; the radial thickness of the diameter-expanding step is larger than the wall thickness of the shaft connecting part.

Preferably, when the stop member is in contact with the proximal bearing (second proximal bearing) for limiting, an axial distance between the diameter-expanding step and the proximal end surface of the shaft connecting portion is larger than an axial distance between the stop member and the limiting member. Preferably, when the stop piece is in contact with the limiting piece for limiting, a certain distance is reserved between the diameter expanding step and the proximal end face of the shaft connecting part.

Preferably, the distal end of the bracket is connected with a distal bearing chamber with a built-in distal bearing; when the pump body is switched between the unfolding state and the folding state, the far-end bearing chamber and the far-end bearing slide relative to the second shaft and keep supporting the second shaft.

Preferably, the distal end of the bracket is provided with a plurality of connecting legs distributed along the circumferential direction; a plurality of the connecting legs are connected to the distal bearing chamber around a peripheral side of the distal bearing chamber.

Preferably, the outer wall of the distal bearing chamber is provided with a receiving groove into which the connecting leg is inserted; the outside of the far-end bearing chamber is fixedly sleeved with a collar, and the collar is sleeved outside the bearing shaft sleeve and the connecting support leg to limit the connecting support leg in the accommodating groove.

Preferably, the collar is a heat shrink tube.

Preferably, the receiving groove includes a plurality of axially extending clamping grooves, and an annular groove communicating with distal ends of the plurality of clamping grooves; the connecting support leg comprises a rod body embedded into the clamping groove and a leg end embedded into the annular groove.

Preferably, the leg ends and the rod body are in a T-shaped structure.

Preferably, the distal bearing chamber comprises an extension segment and a binding segment; the extending section is positioned at the near side of the binding section, the outer diameter of the extending section is smaller than that of the binding section, and a reducing step is arranged between the extending section and the binding section; the accommodating groove is arranged on the outer wall of the binding section; the hoop sleeve is fixedly sleeved outside the binding section; the distal bearing is embedded in the run-in section.

Preferably, the impeller comprises a hub fixedly sleeved on the second shaft and blades arranged on the hub.

Preferably, the hub is glued to the second shaft.

Preferably, the second shaft has an exposed portion with a wall surface exposed in the bracket; at least part of the wall surface of the exposure part is provided with a first spiral structure which extends along the axial direction in a spiral way; the rotation direction of the first spiral structure is the same as the rotation direction of the second shaft. That is, the first helical structure is a right-handed thread in the case of clockwise rotation of the second shaft, or a left-handed thread in the case of counterclockwise rotation of the second shaft, as viewed from the proximal end toward the distal end.

Preferably, the first spiral structure is a spiral groove or a spiral protrusion.

Preferably, the first helical structure is located distally of the hub.

Preferably, the second shaft has a first non-exposed portion sleeved in the hub; at least part of the wall surface of the first non-exposed part is provided with a concave structure. Preferably, the concave structure is a spiral groove provided on a wall surface of the first non-exposed portion.

Preferably, the helical groove extends continuously from the distal end of the hub to the proximal end of the hub.

Preferably, the second shaft is provided with a second non-exposed part sleeved in the distal bearing chamber, and at least part of the wall surface of the second non-exposed part is provided with a second spiral structure, and the rotation direction of the second spiral structure is the same as the rotation direction of the second shaft. That is, the second helical structure is a right-handed thread in the case of clockwise rotation of the second shaft, or a left-handed thread in the case of counterclockwise rotation of the second shaft, as viewed from the proximal end toward the distal end.

Preferably, a spiral groove is formed on the wall surface of the second shaft; the helical groove extends continuously from the proximal end of the hub to the distal end of the second shaft; the spiral direction of the spiral groove is the same as the rotation direction of the second shaft. That is, the helical groove is a right-handed thread in the case where the second shaft rotates clockwise, or a left-handed thread in the case where the second shaft rotates counterclockwise, as viewed from the proximal end toward the distal end.

A catheter pump comprising:

a motor;

a catheter connected proximally to the motor;

a drive shaft driven by the motor;

a pump body having a collapsed state and an expanded state, comprising: a pump housing connected to the distal end of the catheter, an impeller received within the pump housing and driven by the drive shaft;

a distal bearing chamber connected to the distal end of the pump housing and having a distal bearing built therein;

wherein the distal end of the drive shaft passes through the hub of the impeller and extends into the distal bearing;

the distal bearing slides relative to the drive shaft and remains supported by the drive shaft when the pump body is switched between the extended and collapsed states.

Preferably, the drive shaft comprises a first shaft and a second shaft; the second shaft has a stiffness greater than the first shaft; the proximal end of the first shaft is in transmission connection with a rotating shaft of the motor; the distal end of the first shaft is connected to the proximal end of the second shaft; the impeller is fixedly sleeved on the second shaft.

Preferably, the distal end of the bracket, along with the distal bearing chamber and distal bearing, slides along the drive shaft. Specifically, the distal end of the stent, along with the distal bearing chamber and distal bearing, slides along a second axis.

Preferably, in the collapsed state, the distal end face of the drive shaft is distal to the proximal end face of the distal bearing. Specifically, in the collapsed state, the distal end face of the second shaft is distal to the proximal end face of the distal bearing.

Preferably, in the deployed state, the distal end face of the drive shaft is distal to the distal end face of the distal bearing. Specifically, in the deployed state, the distal end face of the second shaft is distal to the distal end face of the distal bearing.

Preferably, in the deployed state, the distance between the distal end face of the drive shaft and the proximal end face of the distal bearing is L1; in the collapsed state, the distance between the distal end face of the drive shaft and the proximal end face of the distal bearing is L2, L1 being greater than L2. Specifically, in the unfolded state, the distance between the distal end face of the second shaft and the proximal end face of the distal bearing is L1; in the folded state, the distance between the distal end face of the second shaft and the proximal end face of the distal bearing is L2, L1 being greater than L2.

Preferably, a non-invasive support is attached to the distal end of the distal bearing housing.

Preferably, a plugging piece for a guide wire to pass through is arranged in the distal bearing chamber; the blocking piece can maintain the blocking state of the position before and after the guide wire passes through. Further, a blocking piece for a guide wire to pass through is arranged in the distal bearing chamber between the distal end of the driving shaft and the proximal end of the noninvasive support; the blocking piece can maintain the blocking state of the position before and after the guide wire passes through.

Preferably, the proximal end of the non-invasive support is provided with an extension into the distal end of the distal bearing chamber, the extension being bonded to the distal end of the distal bearing chamber.

Preferably, the outer wall of the extending part and/or the inner wall of the distal end bearing chamber is provided with a glue containing groove.

Preferably, the glue containing groove is a spiral groove, a linear groove extending along the axial direction or an arc groove extending along the circumferential direction.

A catheter pump comprising:

a motor;

a catheter connected proximally to the motor;

a drive shaft driven by the motor;

a pump body, comprising: a pump casing, an impeller accommodated in the pump casing and driven by the drive shaft; the pump housing includes: a stent, a coating partially covering the stent; the proximal end of the bracket is provided with a connecting secondary pipe, the connecting secondary pipe is provided with a joint part penetrating through at least part of the wall thickness of the connecting secondary pipe, the joint part is accommodated with a joint material which flows into the connecting secondary pipe after being melted and is solidified, and the joint material is arranged at the distal end of the catheter.

A catheter pump comprising:

a motor;

a catheter connected proximally to the motor;

a drive shaft driven by the motor;

a pump body, comprising: a pump casing, an impeller accommodated in the pump casing and driven by the drive shaft; the pump housing includes: a stent, a coating partially covering the stent; the proximal end of the support is provided with a connecting secondary pipe, the connecting secondary pipe is provided with a joint part penetrating through at least part of the wall thickness of the connecting secondary pipe, and the distal end of the catheter is provided with a joint material which is accommodated in the joint part and is formed by hot melting and solidification.

Preferably, the connecting secondary pipe is sleeved outside the distal end of the catheter, an intermediate connecting sleeve is sleeved outside the connecting secondary pipe, and the jointing material is formed by hot melting and then solidifying the intermediate connecting sleeve.

Preferably, part of the intermediate connecting sleeve is positioned at the proximal side of the connecting secondary pipe and fixedly sleeved outside the catheter.

Preferably, part of the intermediate connecting sleeve is adhered and sleeved on the outer wall of the catheter after being hot melted, or part of the intermediate connecting sleeve is adhered on the outer wall of the catheter, or the outer wall of the catheter is provided with an embedded groove for accommodating part of the embedded protrusion formed by solidifying the intermediate connecting sleeve after being hot melted.

Preferably, the jointing material is a structure formed by hot melting, curing and forming or hot pressing part of the guide pipe.

Preferably, the melting point of the bonding material is the same as or similar to the melting point of the material of the catheter.

Preferably, the bonding material is the same as the material of the conduit, or the bonding material and the conduit are both resin materials.

Preferably, the joint part comprises a limiting recess arranged on the pipe wall of the secondary pipe, and the joint material comprises a connecting protrusion formed by hot melting and solidification; the connecting protrusion is clamped into the limiting groove to fix the catheter and the bracket at least axially.

Preferably, the distal end of the connection secondary tube comprises a first connection portion having a limiting recess; the distal end of the catheter includes a second connection portion having a connection protrusion; the second connecting part is sleeved outside the first connecting part, and the connecting protrusion is clamped into the limiting groove.

Preferably, the second connecting portion is cured to form the connecting protrusion after a part of the catheter material flows into the limit recess by hot melting.

Preferably, the second connecting portion further has an adhesive surface to which the first connecting portion is adhered.

Preferably, the second connection portion is cured by hot melting to form the bonding surface.

Preferably, the limiting recess penetrates the wall of the connecting secondary pipe in a radial direction.

Preferably, the limiting recess comprises a plurality of connecting holes which are arranged on the connecting secondary pipe and radially penetrate through the wall of the connecting secondary pipe.

Preferably, the connection hole is a long hole extending in the circumferential direction; the plurality of connecting holes are arranged in parallel along the axial direction of the connecting secondary pipe.

Preferably, adjacent two of the connecting holes are at least partially staggered in the axial direction.

Preferably, adjacent two of the connecting holes are at least partially overlapped in the axial direction.

Preferably, two adjacent connecting holes have overlapping portions in the axial direction; the circumferential length of the overlapping portion is greater than the axial width of the connecting hole.

Preferably, the connection hole has a first overlapping portion and a second overlapping portion that axially overlap with the adjacent connection hole; the first overlapping part is provided with a first hole end, and the second overlapping part is provided with a second hole end; the first overlap portion and the second overlap portion have equal circumferential lengths.

Preferably, the connection hole has a first hole end and a second hole end in a circumferential direction; the first and second bore ends have end spacers; the circumferential length of the end gap is less than half the circumference of the location.

Preferably, the connection hole has a first hole end and a second hole end in a circumferential direction; the first and second bore ends have end spacers; the circumferential length of the end gap is greater than the axial width of the connecting hole.

Preferably, a hole spacer is provided between two adjacent connecting holes; the circumferential width of the hole spacing portion is smaller than the axial width of the connecting hole. Preferably, the connecting holes on both axial sides of a connecting hole are aligned in the axial direction.

Preferably, a third connecting part is further arranged on the radial inner side of the first connecting part; the connecting protrusion penetrates through the limiting recess and is adhered to or integrally constructed with the third connecting portion.

Preferably, the third connecting portion and the second connecting portion are made of the same material.

Preferably, the third connecting portion is of unitary construction with the conduit.

Preferably, a wall clamping jack is arranged on the wall of the catheter at the distal end of the catheter; the radial outer pipe wall of the double-wall jack is the second connecting part, and the radial inner pipe wall of the double-wall jack is the third connecting part; the double-walled insertion hole forms an insertion opening into which the first connection portion is inserted, on an end face of the distal end of the catheter.

Preferably, the connecting secondary tube is further provided with a positioning part at the far side of the first connecting part; the positioning part is used for positioning a proximal bearing positioned in the connecting secondary pipe; the proximal end bearing is sleeved outside the driving shaft to rotatably support the driving shaft; the outer wall of the proximal bearing is provided with a matching part which is jointed with the positioning part; the positioning part and the matching part form a buckling structure.

Preferably, the positioning part comprises a plurality of male buckles which are distributed along the circumferential direction and protrude inwards along the radial direction; the matching part comprises a clamping groove clamped by the male buckle on the outer wall of the proximal bearing.

Preferably, a retainer ring is further fixed inside the connecting secondary pipe at the proximal side of the proximal end bearing; the retainer ring is in contact limit with the distal end face of the third connecting part; the spacer ring is spaced from the drive shaft a distance greater than the distance between the proximal bearing and the drive shaft.

Preferably, a proximal bearing is provided in the connection sub-tube for supporting the drive shaft.

The assembly method of support and conduit of the conduit pump, the said conduit is used for wearing and setting up the drive shaft which drives the impeller to rotate, the said support is used for supporting and expanding the tectorial membrane and forming and holding the rotational space of the impeller; the proximal end of the bracket is provided with a connecting secondary pipe, the connecting secondary pipe is provided with a joint part penetrating through at least part of the wall thickness of the connecting secondary pipe, and the distal end of the catheter is provided with a material part; wherein, the assembly method includes: and covering the material part outside the joint part, and thermally fusing the material part to form a flowing material flowing into the joint part, and solidifying the flowing material to form a connecting structure for connecting the catheter and the stent.

Preferably, the material portion is naturally cooled to solidify the flowable material.

Preferably, the material portion is integrally provided at the distal end of the catheter; wherein, the assembly method includes: and sleeving the distal end of the catheter outside the connecting secondary pipe, and hot-melting the distal end of the catheter to enable part of catheter material to flow into the joint part, and solidifying the material flowing into the joint part to form a connecting structure for connecting the catheter and the bracket.

Preferably, the distal end of the catheter is provided with a double-walled socket; the distal end of the catheter has an outer wall radially outward of the wall-clamping receptacle and an inner wall radially inward of the wall-clamping receptacle; wherein, the assembly method includes: inserting the connection secondary tube into the double-wall jack so that the joint is positioned in the double-wall jack, hot-melting the outer tube wall to enable part of the catheter material to flow into the joint, and solidifying the material flowing into the joint to form a connection structure for connecting the catheter and the bracket.

A catheter pump comprising:

a motor;

a catheter connected proximally to the motor;

a drive shaft driven by the motor;

a pump body, comprising: a pump casing, an impeller accommodated in the pump casing and driven by the drive shaft; the pump housing includes: a stent, a coating partially covering the stent;

A distal bearing chamber having a distal bearing disposed therein, the distal end of the drive shaft being disposed through the distal bearing; the proximal end of the support is connected with the distal end of the catheter, a plurality of spaced connecting support legs are formed at the distal end of the support, and the connecting support legs are embedded in the accommodating groove of the outer wall of the distal end bearing chamber.

Preferably, the outer fixing sleeve of the far-end bearing chamber is provided with a sleeve; the hoop sleeve is sleeved outside the far-end bearing chamber and the connecting support legs to limit the connecting support legs in the accommodating groove.

Preferably, the outer diameter is smaller than the outer diameter of the binding section, and a reducing step is arranged between the extending section and the binding section; the accommodating groove is arranged on the outer wall of the binding section; the hoop sleeve is fixedly sleeved outside the binding section; the distal bearing is embedded in the run-in section.

A pump body assembly method of catheter pump, the said pump body includes the support, impeller shaft with impeller, distal end bearing chamber; wherein, the far end of the bracket is provided with a plurality of connecting supporting legs at intervals, and the far end bearing chamber is provided with an accommodating groove; the pump body assembling method comprises the following steps: the connecting support legs are opened radially, the impeller shaft and the far-end bearing chamber penetrate from the far end of the support to the near end of the support, the connecting support legs are placed in the containing groove for positioning, the hoop sleeve is sleeved outside the far-end bearing chamber, and the connecting support legs are limited in the containing groove.

Preferably, the distal end of the impeller shaft is threaded into the distal bearing chamber; the impeller shaft and the distal bearing chamber are arranged to move proximally from the distal end of the bracket together after the plurality of connecting legs are radially opened.

Preferably, a plurality of the connecting legs are radially opened, the impeller shaft is firstly penetrated from the distal end of the bracket to the proximal end thereof, and then the distal bearing chamber is fed from the distal end of the bracket to the distal end which is surrounded by the plurality of connecting legs and is inserted by the impeller shaft.

Preferably, a plurality of said connecting legs are radially opened, a distal bearing chamber is fed into a plurality of said connecting legs and a receiving groove is aligned with said connecting legs, said connecting legs being positioned in said receiving groove.

Preferably, the heat-shrinkable sleeve is sleeved outside the distal bearing chamber and is formed after heat shrinkage.

Compared with the prior art, the utility model has the following beneficial effects:

in one embodiment of the present disclosure, a catheter pump is provided having a motor, a catheter coupled at a proximal end to the motor via a coupler, a drive shaft disposed through the catheter, the proximal end of the drive shaft being coupled to the motor shaft; and a pump body. Wherein the pump body includes: a pump housing, an impeller disposed within the pump housing and connected to a distal end of the drive shaft; the pump casing includes: a stent with a proximal end connected to the distal end of the catheter and a covering film partially covering the stent; a non-invasive support attached to the distal end of the stent. By inserting the pump body of the catheter pump to the expected position of the heart of the subject, the heart is assisted to pump blood, and adverse events of blood damage are obviously reduced.

The utility model provides a catheter pump in this disclosed one embodiment, through setting up the first axle of braided structure, be covered with on the first axle and weave the clearance and communicate the inside and outside of first axle, and then form the interior runner that perfusate flows simultaneously, realize the large tracts of land flow of perfusate, avoid the perfusion pressure too big.

And, the inside and outside runner that the first axle formed through weaving structure flows in the near side and the distal side of impeller respectively, avoids blood to enter into in the pipe and the drive shaft in, stabilizes the blood flow in the pump, reduces the influence to the pump efficiency and the risk that thrombus produced.

In the catheter pump provided by the embodiment of the disclosure, when the pump body is switched between the unfolded state and the folded state, the distal bearing slides relative to the driving shaft and keeps supporting the driving shaft, so that the driving shaft is prevented from falling out of the distal bearing, and the pump body can be conveniently extended and folded in the axial direction.

In one embodiment of the present disclosure, a drive shaft of a catheter pump is provided, wherein a spiral groove or spiral protrusion is formed on at least a portion of the outer and/or inner surface (outer and/or inner wall) of the drive shaft, and the spiral groove or protrusion has a rotation direction consistent with the rotation direction of the drive shaft, so as to form a pumping effect, pump perfusate distally, and prevent blood from entering at the distal end of the catheter, and avoid thrombus formation at the distal end of the catheter.

According to the catheter pump provided by the embodiment of the disclosure, the connecting secondary pipe is arranged at the proximal end of the support, the connecting secondary pipe is provided with the joint part penetrating through at least part of the wall thickness of the connecting secondary pipe, the joint part is internally provided with the joint material which flows into the connecting secondary pipe after being melted and solidified, the joint material is arranged at the distal end of the catheter, and the catheter and the support are formed to be at least limited and fixed in the axial direction by the joint material formed by melting and solidifying, so that the mechanical connection of the support and the catheter is realized, and compared with the chemical connection in an adhesive mode, the connecting strength is higher.

Further, in an embodiment of the present disclosure, a connection manner between a catheter and a stent is provided, where a matched limiting recess and a connecting protrusion are formed between the stent and the catheter, so as to form mechanical axial limiting and circumferential limiting, thereby realizing mechanical connection between the stent and the catheter, and the connection strength is higher compared with chemical connection in an adhesive form.

And the use of spacing sunken not only can save the joint material of support and pipe connection position, promote more deformation space for deformation, make the connection position have better flexibility, but also can promote the connection area of pipe and support for form axial backstop or fixed knot structure between pipe and the support, thereby improve at least the joint strength of pipe and support along the axial.

In one embodiment of the disclosure, a connection manner between a distal bearing chamber and a non-invasive support is provided, and an adhesive containing groove is formed at a distal end of the distal bearing chamber and/or a proximal end of the non-invasive support, so that an adhesive amount and a joint area are increased, and a connection strength of the two is further improved.

In one embodiment of the present disclosure, a second shaft structure in a pump body is provided, wherein a spiral groove or spiral protrusion spiral structure is formed on at least an outer wall of an exposed portion in a bracket, and the spiral structure is the same as a rotation direction of a driving shaft to form a pumping effect, so that blood is pumped into a pump shell, and the blood is prevented from reversely entering a distal bearing chamber, so that thrombus is prevented from being formed.

In one embodiment of the disclosure, a second shaft structure in a pump body is provided, a spiral groove is formed on the outer wall of a part of the second shaft in a hub cavity, and by arranging the spiral groove, the glue containing amount of the second shaft and the hub can be increased, and the joint strength of an impeller and the hub is improved.

One embodiment of the present disclosure provides a perfusate inlet flow channel design in which perfusate flows forward in the gap (outer flow channel) between the catheter and the drive shaft, since the first shaft of the drive shaft is of a liquid permeable construction. Therefore, the perfusion liquid flows forwards and permeates into the inner runner of the first shaft, blood can be prevented from entering the far-end bearing chamber or the noninvasive support piece under the action of the perfusion liquid, adverse effects such as thrombus and the like are avoided, and meanwhile, the bearings supporting the driving shaft are lubricated, so that the stable running of the bearings is ensured.

An embodiment of the disclosure provides a pump body of a catheter pump, a coating film does not generate stretching deformation in a radial unfolding state, the coating film has strong deformation resistance, and further the shape of a supporting member can be stably restrained and maintained in the radial unfolding state, a pump gap is kept, and the pump body keeps better pump efficiency.

An embodiment of the present disclosure provides a novel structure of a distal end of a stent of a catheter pump, in which a dispersed leg structure is formed at the distal end of the stent, so that the distal end of the stent is conveniently fed into the stent and is provided with an impeller and an impeller shaft (a second shaft), thereby providing a reliable solution for manufacturing and assembling with better practicability for an expanded and folded pump body.

Drawings

FIG. 1 is a schematic illustration of an interventional catheter pump provided in accordance with one embodiment of the present utility model;

FIG. 2 is a front view of FIG. 1;

fig. 3 is a perspective view of fig. 1 without a coating;

FIG. 4 is a front view of FIG. 3;

FIG. 5 is an enlarged view of the pump body of FIG. 4 without a coating;

FIG. 6 is an enlarged view of a portion of FIG. 5;

FIG. 7 is an enlarged view of the pump body of FIG. 3 without a coating;

FIG. 8 is a schematic view of the pump body of FIG. 2;

FIG. 9 is a partial cross-sectional view of FIG. 8;

fig. 10 is a perspective view of fig. 8;

FIG. 11 is a perspective view of the film of FIG. 8;

FIG. 12 is a front view of FIG. 11;

FIG. 13 is a schematic illustration of a pump body of an interventional catheter pump provided in accordance with another embodiment of the present disclosure;

FIG. 14 is a graph of diameter variation of 6 different pump bodies of the present disclosure under fluid back pressure;

FIG. 15 is a cross-sectional view of a pump body structure provided in one embodiment of the present disclosure;

FIG. 16 is an enlarged view of a portion of FIG. 15;

FIG. 17 is an enlarged view of a portion of FIG. 15;

FIG. 18 is an enlarged view of a portion of FIG. 15;

FIG. 19 is a cross-sectional view of a pump body structure provided in one embodiment of the present disclosure;

FIG. 20 is an enlarged view of a portion of FIG. 19;

FIG. 21 is an enlarged view of a portion of FIG. 19;

FIG. 22 is a cross-sectional view of a pump body without a coating provided in one embodiment of the present disclosure;

FIG. 23 is a schematic perspective view of the bracket of FIG. 22;

FIG. 24 is a schematic view of the connecting sub-pipe structure of FIG. 23;

FIG. 25 is a schematic illustration of a stent structure provided in one embodiment of the present disclosure;

FIG. 26 is an enlarged schematic view of a portion of the support grid of FIG. 25;

FIG. 27 is a schematic view of the mating of the distal end of the stent of FIG. 25 with a distal bearing housing;

FIG. 28 is a cross-sectional view of a pump body without a coating provided in one embodiment of the present disclosure;

FIG. 29 is an enlarged schematic view of the first and second shaft connection structures of FIG. 28;

FIG. 30 is an enlarged schematic view of the second shaft and distal bearing chamber connection of FIG. 28;

Fig. 31 is a schematic view of the connection of the stent of fig. 29 to a catheter.

Detailed Description

In order to make the technical solution of the present utility model better understood by those skilled in the art, the technical solution of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model, and it is apparent that the described embodiments are only some embodiments of the present utility model, not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, shall fall within the scope of the utility model.

It will be understood that when an element is referred to as being "disposed" on another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "left," "right," and the like are used herein for illustrative purposes only and are not meant to be the only embodiment.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this utility model belongs. The terminology used herein in the description of the utility model is for the purpose of describing particular embodiments only and is not intended to be limiting of the utility model. The term "and/or" as used herein includes any and all combinations of one or more of the associated listed items.

The terms "proximal", "distal" and "anterior", "posterior" are used herein with respect to a clinician manipulating a catheter pump. The terms "proximal", "posterior" and "anterior" refer to portions relatively closer to the clinician, and the terms "distal" and "anterior" refer to portions relatively farther from the clinician. For example, the extracorporeal portion is proximal and posterior and the intervening intracorporeal portion is distal and anterior.

The catheter pump of the present utility model defines an "axial direction" or an "axial extending direction" with respect to the extending direction of the output shaft or the connecting shaft, the driving shaft 300, the first shaft 350, and the second shaft 355, and the driving shaft 300 includes the first shaft 350 and the second shaft 355, and the axial direction of the driving shaft 300 refers to the axial direction when the driving shaft 300 is adjusted to linearly extend. The terms "inner" and "outer" as used herein are relative to an axially extending centerline, with the direction being "inner" relative to the centerline and the direction being "outer" relative to the centerline.

It is to be understood that the terms "proximal," "distal," "rear," "front," "inner," "outer," and these orientations are defined for convenience in description. However, catheter pumps may be used in many orientations and positions, and thus these terms of expressing relative positional relationships are not limiting and absolute. In the present utility model, the above definitions should follow the above-mentioned explicit definitions and definitions, if they are defined otherwise.

In the present utility model, unless explicitly specified and limited otherwise, terms such as "coupled," "connected," and the like are to be construed broadly and include, for example, either connected, detachably connected, movably connected, or integrated; can be directly connected or indirectly connected through an intermediate medium, and can be communicated with the inside of two elements or the interaction relationship of the two elements. The specific meaning of the above terms in the present utility model can be understood by those of ordinary skill in the art according to the specific circumstances.

The catheter pump provided by the embodiment of the utility model is used for assisting in heart failure, and can pump blood to the heart so as to realize partial blood pumping function of the heart. In a scenario suitable for left ventricular assist, a catheter pump pumps blood from the left ventricle into the main artery, providing support for blood circulation, reducing the workload of the subject's heart, or providing additional sustained pumping power support when the heart is not sufficiently pumping.

Of course, the catheter pump may also be used to intervene as desired in other target locations of the subject, such as the right ventricle, blood vessels, or other organ interiors, depending on the interventional procedure.

Referring to fig. 1 to 12, the catheter pump comprises a drive assembly 1 and a working assembly. The drive assembly 1 includes a housing and a motor housed within the housing and having an output shaft. The working assembly comprises a guide tube 3, a driving shaft 300 penetrating the guide tube 3, and a pump body 4 driven by the driving shaft 300. The drive assembly 1 is disposed at the proximal end of the catheter 3, is coupled to the catheter 3 via the coupler 2, and is coupled to the pump body 4 via a first shaft 350 disposed through the catheter 3. The driving component 1 provides power for the working component to drive the working component to realize the blood pumping function.

The pump body 4 may be delivered to a desired location of the heart, such as the left ventricle for pumping blood, through the catheter 3, and includes a pump housing 363 having a blood inlet 403 and a blood outlet 402, and an impeller 410 housed within the pump housing 363. The impeller 410 is used to power the flow of blood, and the pump housing 363 includes at least a membrane 401 defining a blood flow path.

The pump body 4 has an interposed configuration and an operating configuration. In the corresponding access configuration of the pump body 4, the pump housing 363 and impeller 410 are in a radially collapsed state so that the pump body 4 is accessed and/or delivered within the vasculature of the subject at a first outer diameter dimension. In the corresponding operating configuration of the pump body 4, the pump housing 363 and the impeller 410 are in a radially expanded condition so that the pump body 4 delivers blood at a desired location to the pump body 4 at a second outside diameter dimension greater than the first outside diameter dimension.

The pump body 4 includes a radially collapsed state and a radially expanded state, and the pump housing 363 is operable to switch between the radially collapsed state and the radially expanded state. In contrast to the unstressed state, the coating 401 does not undergo tensile deformation in the radially expanded state of the pump housing 363.

As shown in fig. 9, the impeller 410 includes a hub 412 coupled to the distal end of the driving shaft 300 and blades 411 supported on the outer wall of the hub 412. In the corresponding insertion configuration of the pump body 4, the blades 411 are wrapped around the outer wall of the hub 412 and at least partially contact the inner wall of the pump casing 363. In the corresponding operating configuration of the pump body 4, the blades 411 extend radially outwardly from the hub 412 and are spaced from the inner wall of the pump casing 363, avoiding that the pump casing 363 affects the rotation of the blades 411 and avoiding that the rotation of the blades 411 damages the pump casing 363.

The pump housing 363 further includes a bracket 404 for supporting the deployment membrane 401. The holder 404 may be provided inside the coating 401 or outside the coating 401 to support the coating 401. In the radially expanded state, the stent 404 contacts the inner wall of the stent 401 and expands in the radial direction to support and expand the stent 401. Wherein the coating 401 does not undergo tensile deformation in the unstressed state as compared to the radially expanded state of the coating 401 in which the pump casing 363 is unstressed.

The radially expanded state in which the pump casing 363 is not subjected to force is a naturally expanded state in which the impeller 410 is not rotated.

The radially expanded state includes a natural expanded state corresponding to when the impeller 410 is not rotated. The critical point stress of the tensile deformation of the coating film 401 is equal to or greater than the force applied by the bracket 404 when the pump case 363 is in the natural expansion state. In this way, when only the stent 404 applies the radial support expansion force to the coating 401, the coating 401 does not undergo the tensile deformation in the natural expansion state since the critical tensile deformation force of the coating 401 is not reached.

The radially expanded state also includes an operational state corresponding to the rotation of the impeller 410. In order to ensure the toughness of the coating 401, a more stable pump gap is provided, the pump efficiency is stabilized, and the critical point stress of the tensile deformation of the coating 401 is equal to or greater than the force applied to the coating 401 by the blood back pressure caused by the rotation of the impeller 410 when the pump body 4 is in the maximum working condition.

The maximum operating condition of the pump body 4 corresponds to the maximum rotational speed of the impeller 410 at rated power. At this time, the pump flow rate corresponds to the maximum value, and the blood back pressure is also at the maximum value. In this embodiment, the maximum value of the blood back pressure still does not exceed the critical point stress of the tensile deformation of the coating film 401, and further the coating film 401 still does not generate tensile deformation in the working state of the rotation of the impeller 410, so as to avoid the change of the pump gap and stabilize the pump efficiency.

That is, the material strength of the coating 401 itself is sufficient to resist the outward expansion force of the stent 404, and thus the circumferential stretching deformation amount of the coating 401 is 0 when the pump casing 363 is switched from the radially collapsed state to the naturally expanded state, and no circumferential stretching deformation is generated.

Further, the material strength of the coating film 401 itself is sufficient to resist the force applied thereto by the blood back pressure due to the rotation of the impeller 410, and thus the circumferential stretching deformation amount of the coating film 401 when the pump casing 363 is switched from the natural expanding state to the operating state is 0.

It should be noted that the tensile strain of the coating film 401 in the present utility model means that the coating film 401 is deformed in the circumferential direction. When subjected to radial force, the circumferential length (circumferential length) becomes large. However, when the coating 401 itself has wrinkles, the stretching of the coating 401 is not performed by flattening the wrinkles due to the expansion of the stent 404.

The folds of the film 401 are most often due to folding. The membrane 401 is forced to compress and fold due to the radial constraint of the folded sheath, thereby causing wrinkles to occur. Of course, this does not exclude wrinkles in the cover film 401 caused by other factors. For example, it may be formed at the time of manufacture, or deformed by itself at the time of placement, or generated at the time of testing, or the like. The folds may be in the form of, for example, folds, (fine) wrinkles.

The material of the coating film 401 is TPU (thermoplastic polyurethane elastomer rubber) or PEBAX material or PTFE (polytetrafluoroethylene). Preferably, the cover film 401 is a block polyether amide resin material such as PEBAX. The coating 401 has no loss of mechanical properties under repeated deformation, is fatigue resistant, and has good rebound and elastic recovery properties and accurate dimensional stability. Further, the pump gap is stably maintained without tension deformation by the support of the bracket 404.

The coating film 401 is supported and resists the radial expansion force of the support 404 by the self material, and does not generate stretching deformation when the pump casing 363 is in a natural expansion state, and the stretching deformation is circumferential stretching deformation.

It will be appreciated that the inner diameter or cross-sectional area of the membrane 401 is the same in the unstressed state as compared to the naturally deployed state and is unchanged. The cover 401 has a cylindrical structure when the pump housing 363 is not under load and is not supported by the bracket 404. It is also understood that the natural expansion of the cover 401 does not cause any tensile deformation, and the amount of tensile deformation is 0, compared to the state in which the stent 404 is expanded from inside to outside.

The natural deployed state is compared to the operating state in which the impeller 410 rotationally drives the fluid. When the impeller 410 rotates to drive the blood flow, the blood exerts a certain radial expansion force (fluid back pressure) on the membrane 401.

With the above description in mind, the pump body 4 comprises a radially collapsed condition suitable for delivery in the vasculature of a subject, a natural deployed condition when the corresponding impeller 410 is not rotating, and an operating condition when the corresponding impeller 410 is rotating. During the switching of the pump body 4 from the natural unfolded state to the working state, the blood back pressure exerted on the membrane 401 by the rotation of the impeller 410 causes the folds of the membrane 401 to be at least partially flattened.

The above-mentioned diameter increasing rate is a diameter changing rate of the cover film 401 in the natural unfolding state of the pump casing 363 compared with the working state, and is determined by the number of folds and the degree of undulation of the cover film 401, and is further determined by the flexibility of the material of the cover film 401.

Specifically, the flexibility of the material of the film 401 largely determines the number of wrinkles and the degree of waviness. That is, the lower the flexibility of the material of the coating 401, the greater the number of folds and the greater the degree of waviness of the coating 401, and the closer to 3% the increase rate of the diameter of the coating 401 when the folds are flattened. In contrast, the better the flexibility of the material of the film 401, the fewer the number of folds and the smaller the degree of waviness of the film 401, and the more the rate of increase in the diameter of the film 401 deviates from 3% when the folds are flattened.

Thus, in some situations that cannot be explicitly excluded, where there is little wrinkling due to the selected material of the film 401 conforming to particularly soft characteristics, the contribution of flattening of the wrinkles to the rate of increase in the diameter of the film 401 may be close to 0.

The covering film 401 is in an integrally formed structure and can be unfolded by the bracket 404, and the distal opening of the covering film 401 and the region of the distal end of the bracket 404, which is not covered by the covering film 401, jointly form the blood inlet 403 of the pump housing 363. The distal end of the covering film 401 is also provided with a connecting strip 19, and the distal end of the connecting strip 19 is connected to the distal bearing chamber 6.

The cover 401 is in a radially expanded state and the connecting strip 19 is in a substantially straightened and stretched state. The distal and proximal ends of the membrane 401 are respectively fixed by the connecting strips 19 and the connecting sleeve 16 of the proximal end 17 of the membrane 401, so that the membrane 401 is in an overall flat state in the axial direction, and folds of the membrane 401 are smoothed as much as possible, so that an inner wall which is as smooth as possible is provided. While smooth inner walls are known to be advantageous for the hydrodynamic effect of the pump.

Of course, in other embodiments, the distal end 18 of the cover 401 may be coupled to the stent 404. For example, the inner wall of distal end 18 of cover 401 is bonded to the outer wall of stent 404 and expands as stent 404 is contracted.

In the natural deployed state, the holder 404 has a contact support portion that contacts the coating film 401. As shown in fig. 7 and 9, the stent 404 includes a generally tapered proximal end 121 of the stent 404 and a distal end 123 of the stent 404, and a generally cylindrical stent section 122 between the proximal end 121 of the stent 404 and the distal end 123 of the stent 404. Wherein at least a portion of the axial length of the support 404 section 122 constitutes a contact support.

The cover 401 is sleeved outside the support 404 section 122, and is supported by the support 404 section 122 in a contact manner so as to construct a pump shell 363 in a stable cylindrical shape. The distal end 18 (end face) of the cover 401 does not extend beyond the stent 404 segment 122.

In the radially expanded state, there are an operating state in which the impeller 410 rotates to drive the blood flow and a natural expanded state in which the impeller 410 is stationary. The different states of blood (stationary and flowing) cause different forces on the membrane 401. Further, in a state where the impeller 410 is rotated to drive the blood flow, there is not only a supporting force of the stent 404 against the membrane 401 but also a radial pushing (fluid back pressure) of the blood against the membrane 401 due to the driving of the impeller 410.

Therefore, in the operating state of the impeller 410 at a high rotation speed (thousands of revolutions per minute or more) as compared with the non-operating state (natural developed state), the coating film 401 is stretched to some extent in the circumferential direction of the coating film 401 due to the wrinkles being flattened. This elongation is caused by the wrinkles being flattened, but the film 401 itself is not subjected to tensile deformation in the circumferential direction.

The diameter of the coating 401 in the operating state of the pump body 4 is larger than the diameter of the pump body 4 in the natural deployment state. This diameter is the diameter of the inner cavity enclosed by the membrane 401. In the working state, due to the existence of the fluid back pressure, at least part of folds of the covering film 401 are flattened, so that the cross-sectional shape of the enclosed inner cavity is more circular, the inner wall of the covering film 401 is smoother, and the diameter of the covering film 401 (the diameter of the enclosed cavity) is further increased.

In an operating state, the blood back pressure exerted on the membrane 401 caused by the rotation of the impeller 410 causes the folds of the membrane 401 to be at least partially flattened. During the switching of the pump body 4 from the natural unfolded state to the working state, the blood back pressure exerted on the membrane 401 by the rotation of the impeller 410 causes the folds of the membrane 401 to be at least partially flattened. The flattening of the pleats results in a rate of increase in the diameter of the coating 401 of no more than 3%, further no more than 2%, and even no more than 1%.

The rate of increase in diameter is seen in FIG. 14 for the diameter variation of 6 sets of membranes 401 (where 1-3-A represent different membrane 401 names) at different back pressures. Wherein two pressure endpoints and a diameter of the coating 401 at approximately mid-pressure are shown in each graph. As can be seen from each graph, as the back pressure increases, the coating film 401 stretches to some extent in the circumferential direction, but the diameter increases to within 0.1 mm.

In the transition from the natural deployment state to the working state, at least the sub-process in which the diameter of the coating film 401 does not increase exists. As the back pressure increases during testing, the diameter of the coating 401 sometimes remains the same or even decreases over a range of pressures.

The reason why the above-described existence of the process in which the diameter does not increase is caused is that the cover film 401 assumes a cross-sectional shape that is circular-like but not strictly circular in the natural developed state due to the existence of the wrinkles. The corrugations include radially inward depressions, and radially outward protrusions are also possible. If the diameter measurement points are two convex points, the diameter measured initially is larger, and after the folds are flattened, the convex is flattened, thereby causing a phenomenon that the diameter is reduced although the back pressure is increased.

Of course, this also further or indirectly demonstrates that the circumferential elongation of the cover film 401 in the present utility model is due to the flattening of the folds and not the stretching deformation. Since the tensile deformation results in an increase in the diameter persistence without the occurrence of unchanged and decreased phenomena.

In one embodiment, at least a portion of the contact support (the leg 404 section 122) is spaced apart from the cover 401 in the operational state. The cover film 401 is further flattened by the fluid back pressure, and the inner diameter is increased to be separated from the contact support portion. And the film 401 itself is limited from tensile deformation due to its toughness. And the pleats are further flattened so that the cover film 401 is elongated circumferentially, but the elongation varies by less than 3%. The circumferential elongation change is small, so that the interval gap between the impeller 410 and the coating film 401 can be maintained under the working state, and the continuous stability of the pump efficiency is maintained.

During the transition of the pump housing 363 from the radially collapsed state to the radially expanded state, relative movement is permitted between the contact support and the cover 401, and the location where the cover 401 makes contact with the contact support, such as the stent 404 segment 122, is permitted to change. The relative position of the bracket 404 and the cover 401 is fixed without change.

The contact support portion and the covering film 401 are only in contact support, and are not connected, so that a certain degree of relative movement is formed between the contact support portion and the covering film 401 during the unfolding process of the covering film 401, and therefore the desired unfolding of the contact support portion and the covering film 401 is achieved. And, the contact support provides circumferential support force to the cover 401 without providing radial and circumferential relative motion constraints, allowing for radial or circumferential relative motion of the cover 401 relative to the contact support such that the portion of the cover 401 in contact with the contact support or stent 404 changes during deployment.

As shown in fig. 10 to 13, the covering film 401 includes a cylindrical section 110, a proximal tapered section 111 provided at a proximal end of the cylindrical section 110, the cylindrical section 110 having an axial length greater than that of the proximal tapered section 111, and a blood outlet 402 extending from the proximal tapered section 111 to the cylindrical section 110.

The proximal end of the proximal conical section 111 is provided with a connection sleeve 16, the connection sleeve 16 being connected to the outer wall of the catheter 3, whereby the connection of the distal end 18 of the covering membrane 401 is achieved. The connecting sleeve 16 can be connected with the catheter 3 by bonding, hot melting or crimping. The connection location of the cover 401 to the catheter 3 or the location of the connection sleeve 16 is located proximal to the proximal bearing chamber 340.

A part of the blood outlet 402 is located at the proximal conical section 111, another part of the blood outlet 402 is located at the cylindrical section 110, and the plurality of blood outlets 402 are arranged in the circumferential direction. The blood output from the blood outlet 402 of the part of the cylinder section 110 forms centrifugal flow, and the plurality of blood outlets 402 can flow outwards to stabilize the position of the pump body 4 and the blood flow. The blood output from the partial blood outlet 402 of the proximal cone section 111 generally forms an axial flow, which together with the partial blood outlet 402 of the cylinder section 110 ensures the flow of the blood outlet 402, avoiding flow losses.

To maintain structural strength of the front end of the membrane 401, and to maintain stability of the shape and structure, the blood outlet 402 of at least a part of the axial length gradually decreases in circumferential width in the direction from the distal end toward the proximal end.

As shown in fig. 11 and 12, the blood outlet 402 in the proximal cone section 111 has a gradually decreasing circumferential width as it extends from the distal end to the proximal end, and the blood outlet 402 in the other part of the cylinder section 110 has a gradually increasing circumferential width as it extends from the distal end to the proximal end. As shown in fig. 13, in one embodiment, the blood outlet 402 tapers in circumferential width in a direction extending proximally from the distal end.

As shown in fig. 12, the part of the blood outlet 402 located at the proximal cone section 111 is the rear blood outlet section 21, and the other part of the blood outlet 402 located at the cylinder section 110 is the front blood outlet section 20. Wherein the blood outlet 402 has a length in the portion of the proximal cone section 111 that is greater than the length of the portion of the barrel section 110. That is, the length of the rear blood outlet part 21 is longer than the length of the front blood outlet part 20.

The circumferential width of the front blood outlet part 20, at least part of which is the (axial) length, is greater than or equal to the maximum circumferential width of the rear blood outlet part 21. In the rear blood outlet part 21, the circumferential width of the downstream part is smaller than or equal to the circumferential width of the upstream part at any two axial parts of the blood outlet 402. The blood outlet 402 has a proximal end with a circumferential width that is less than a circumferential width of its distal end.

In this embodiment, the support 404 or the single support 404 is an integrally formed structure, the support 404 and the covering film 401 are in a separate structure, and at least a part of the support 404 is located inside the covering film 401 and contacts the inner wall of the supporting covering film 401.

In the unstressed radially expanded state, the stent 404 is radially constrained by the membrane 401 and is not fully expanded by the pump housing 363. The stent 404 is made of a memory alloy material, and after the restriction of the sheath is lost, the stent 404 recovers the shape to prop open the coating 401 until the restriction of the coating 401 can not be continued to prop open. At this time, the stent 404 provides a radially outward supporting force to the stent 401, and the stent 401 resists the deformation of the stent 404 by virtue of its own toughness, does not generate tensile deformation, and maintains the stability of the shape.

The folding and unfolding process of the pump body 4 is as follows: during the intervention of the pump body 4 into the left ventricle, the pump body 4 is in a radially constrained state (collapsed state) due to an externally applied radially constraining force. Alternatively, the pump head 4 is collapsible only during intervention in the subject's vasculature. After intervention into the left ventricle (forward delivery in the vasculature in collapsed configuration) or into the subject's vasculature (forward delivery in the vasculature in expanded configuration), the radial constraint is removed and the stent 404 self expands by virtue of its memory properties and the release of the stored energy by the blades 411 of the impeller 410, so that the pump body 4 automatically assumes its unconstrained shape (expanded configuration).

Conversely, when the pump body 4 is required to be withdrawn from the subject, the pump body 4 is folded by the folding sheath, and after the pump body 4 is completely withdrawn from the subject, the constraint of the folding sheath on the pump body 4 is removed, so that the pump body 4 is restored to a natural state with minimum stress, namely an unfolding state.

It should be noted that the stent 404 of the present utility model is not limited to a single stent 404 in the covering film 401, and may include a plurality of stents 404 distributed at different positions in the axial direction to support different portions of the covering film 401. For example, a holder 404 may be provided to support the proximal end 17 of the membrane 401 to stably support the blood outlet 402, maintain the stability of the shape of the blood outlet 402, and reduce the influence on the blood flow.

The stent 404 is in a grid configuration, and the design of multiple meshes, particularly diamond meshes, on the stent 404 facilitates the folding and unfolding of the stent 404. The impeller 410 is housed in the holder 404 and is positioned in the cover 401. The stent 404 is supported on the distal end 18 of the stent 401 with the distal end or distal end 123 of the tapered stent 404 being located outside the distal end 18 of the stent 401 and the proximal end 121 of the tapered stent 404 and the stent 404 segments 122 being located within the stent 401.

The impeller 410 is mounted on a second shaft 355, the second shaft 355 being mounted within the housing 404 and being rotatably supported distally within the distal bearing housing 6. The support 404 is a spindle configuration providing a support space for the impeller 410. The proximal end of the stent 404 is connected to the distal end of the catheter 3, and the proximal end 17 of the membrane 401 is sleeved on the outer wall of the catheter 3 proximally of the stent 404.

The catheter 3 is connected to the proximal end 17 of the support 404 via a proximal bearing housing 340 at its distal end, the proximal bearing housing 340 having

proximal bearings

331, 332 disposed therein for rotatably supporting the drive shaft 300. The distal bearing housing 6 is provided at the distal end of the drive shaft 300 and rotatably supports the distal end of the drive shaft 300 by the distal bearing 62. The bracket 404 maintains the spacing of the proximal bearing chamber 340 and the distal bearing chamber 6, thereby providing stable rotational support for the second shaft 355.

The distal end of the distal bearing housing 6 is connected with a non-invasive support 5. The noninvasive support 5 is a flexible pipe body structure and is characterized in that the end part of the noninvasive support is a flexible bulge in an arc shape or a winding shape, so that the noninvasive support 5 is supported on the inner wall of a ventricle in a noninvasive or non-invasive manner, the blood inlet 403 of the pump body 4 is separated from the inner wall of the ventricle, the suction inlet of the pump body 4 is prevented from being attached to the inner wall of the ventricle due to the reaction force of blood in the working process of the pump body 4, and the effective pumping area is ensured.

The inner diameter of the hollow lumen 502 of the atraumatic support 5 is equal to or slightly larger than the outer diameter (diameter) of the guidewire. For example, the inner diameter of the hollow lumen 502 of the atraumatic support 5 is 1-1.2 times the diameter of the guidewire. The hollow lumen 502 has a sufficiently small inner diameter (about 0.2-0.9 mm) that the resistance to blood entering the lumen is relatively high, prevents blood from entering the pump body 4 through the non-invasive support 5, reduces damage to the blood, and facilitates the blood input into the pump body 4 through the blood inlet 403.

The proximal end of the atraumatic support 5 is inserted into the distal bearing chamber 6, constituting a distal stop for the second shaft 355. The distal end of the second shaft 355 slidably extends into the distal bearing chamber 6 and is rotatably supported. The proximal end face of the atraumatic support 5 constitutes a stop step in the distal bearing chamber 6 for stopping the distal end of the second shaft 355. The pump body 4 is adapted to form a play for the axial relative movement of the second shaft 355 relative to the outer jacket member when it is moved through the blood vessel.

The proximal end of the atraumatic support 5 may be fixed by adhesive to the inner wall of the distal bearing chamber 6. Specifically, the proximal end of the atraumatic support 5 extends into the distal end of the distal bearing chamber 6, adhering to the distal inner wall of the distal bearing chamber 6.

In order to improve the connection strength of the noninvasive support 5 and the distal bearing chamber 6 and avoid the detachment of the noninvasive support 5 from the distal bearing chamber 6, the outer wall of the proximal end of the noninvasive support 5 and/or the inner wall of the distal bearing chamber 6 are provided with glue containing grooves. The glue filling quantity between the two is improved through the glue containing groove, so that the connection strength of the two is improved.

The glue receiving groove is arranged on the outer wall of the proximal end of the noninvasive support 5 or on the inner wall of the distal end bearing chamber 6. The glue-holding grooves can be in various forms, such as discrete dot grooves, long groove structures or spiral grooves. By way of example, the glue groove may be a plurality of axially extending linear grooves, which are arranged in parallel in the circumferential direction.

In other embodiments, the proximal end of the non-invasive support 5 is cylindrical, and the side walls thereof are provided with recessed structures to increase the adhesive bonding area, thereby improving the strength of the connection between the distal bearing chamber 6 and the non-invasive support 5. The recessed structures may be grooves or channels having a shape such as circular, polygonal, or even irregularly shaped channels. The distal inner wall of the distal bearing chamber 6 may also have the same configuration of the recess as the proximal end of the non-invasive support 5, which will not be described in detail.

A stop step is provided in the distal bearing chamber 6. When the proximal end of the non-invasive support 5 is inserted into the distal bearing chamber 6 and moved proximally, the proximal end surface of the non-invasive support 5 is restrained in contact with the stop step. The stop step is formed by a convex structure or reducing inside the distal bearing chamber 6.

In this embodiment, the inside of the distal bearing chamber 6 is a stepped hole, the stop step is a reducing step formed by reducing, the inner diameter of the middle section of the stepped hole is smaller than the holes Duan Najing on the far side and the near side, the hole section in the proximal end of the stepped hole is used for installing the distal bearing 62, and the opposite distal end is used for inserting, assembling and limiting the proximal end of the noninvasive support 5.

A stopper 550 is provided in the distal bearing housing 6, through which the guide wire can pass, the stopper 550 being located between the stop step and the proximal end of the atraumatic support 5 and being sandwiched therebetween. The blocking member 550 is then restrained by the stop step and proximal end of the atraumatic support 5, held in this position, and blocked in place and fed through by the guidewire.

The position is blocked by the blocking piece 550, so that the influence on the blood pumping effect caused by the blood entering the pump body 4 through the noninvasive support piece 5 when the blood is pumped is avoided.

In this embodiment, the pump body 4 is collapsible. The pump body 4 is desired to be small in size from the viewpoints of alleviation of pain to the subject and ease of intervention. In order to provide a strong auxiliary function for the subject, it is desirable that the flow rate of the pump body 4 is large, and the large flow rate generally requires a large size of the pump body 4.

By arranging the foldable pump body 4, the pump body 4 has smaller folding size and larger unfolding size, so that the requirements of relieving the pain of a subject and facilitating the intervention in the intervention/transportation process and providing large flow are met.

From the above, the multi-mesh, especially diamond-mesh design of the stent 404 can achieve a better folding and unfolding by means of the memory properties of the nitinol. The blade 411 is made of a flexible elastic material, and is stored when being folded, and after the external constraint is removed, the stored energy of the blade 411 is released, so that the blade 411 is unfolded.

The pump body 4 is folded by means of external constraint, and after the constraint is removed, the pump body 4 is self-unfolded.

In the present embodiment, the "collapsed state" refers to a state in which the pump body 4 is radially restrained, that is, a state in which the pump body 4 is radially compressed and collapsed to a minimum radial dimension by external pressure. The "expanded state" refers to a state in which the pump body 4 is not radially constrained, that is, a state in which the bracket 404 and the impeller 410 are expanded radially outward to the maximum radial dimension.

The above-mentioned application of external restraint is accomplished by a folding sheath (not shown) slidably fitted over the catheter 3. When the folding sheath tube moves forwards outside the guide tube 3, the pump body 4 can be integrally contained in the folding sheath tube, so that the pump body 4 can be forcedly folded. When the folded sheath moves backwards, the radial constraint imposed by the pump body 4 disappears and the pump body 4 self-expands.

From the above, the collapsing of the pump body 4 is achieved by means of the radial restraining force exerted by the collapsing sheath. And the impeller 410 contained in the pump body 4 is housed in the pump casing 363. Therefore, in essence, the folding process of the pump body 4 is: the folded sheath exerts a radial restraining force on the pump housing 363, which, when the pump housing 363 is radially compressed, exerts a radial restraining force on the impeller 410.

That is, the pump casing 363 is folded directly by the folding sheath, and the impeller 410 is folded directly by the pump casing 363. And as described above, the impeller 410 has elasticity. Therefore, although in the folded state, the impeller 410 is folded to be stored so as to have a radial direction unfolding trend all the time, and thus the impeller 410 contacts with the inner wall of the pump casing 363 and applies a reaction force to the pump casing 363.

After the constraint of the folding sheath is removed, the foldable support 404 supports the elastic covering film 401 to expand under the action of the self memory characteristic until the covering film 401 is constrained to be unable to continue to expand, and the impeller 410 expands automatically under the action of released energy storage. In the deployed state, the outer diameter of the impeller 410 is smaller than the inner diameter of the pump casing 363.

In this way, a space is maintained between the radially outer end of the impeller 410 (i.e., the tips of the blades 411) and the inner wall of the pump casing 363 (specifically, the inner wall of the bracket 404), which is a pump clearance. The presence of the pump gap allows for unimpeded rotation of the impeller 410 without wall slamming.

In addition, from a hydrodynamic point of view, it is desirable that the pump gap size be small and maintained. In this embodiment, the outer diameter of the impeller 410 is slightly smaller than the inner diameter of the bracket 404 as the bracket 404 so that the pump clearance is as small as possible while satisfying the condition that the impeller 410 rotates without colliding with the wall.

The main realization means of the pump gap maintenance is that the support strength provided by the support 404 and the tensile deformation resistance of the coating 401 can resist the back pressure action of the fluid (blood) without excessive deformation, so that the pump gap is stably maintained when the pump shell 363 is stably maintained.

The multi-mesh design of the bracket 404 in combination with the memory alloy material facilitates folding and unfolding. The support 404 includes a generally cylindrical body section 40, a generally tapered inlet section 41 and an outlet section 42 at the axial ends of the body section 40. Wherein the main body section 40, the inlet section 41 and the outlet section 42 are distributed with meshes, and the mesh area of the main body section 40 is smaller than that of the inlet section 41 and/or the outlet section 42.

The cover 401 is in interference fit with the stent 404, the distal end of the cover 401 extends from the main body section 40 of the stent 404, the stent 404 overlaps with the axial portion of the cover 401, the cover 401 covers most of the stent 404, and only the inlet section 41 is exposed to form the blood inlet 403. The proximal end of the membrane 401 is adhesively connected to the catheter 3, and the blood outlet 402 is located at the proximal end of the membrane 401. In the natural deployment state, the outer wall of the body section 40 contacts the inner wall of the membrane 401 upon deployment to support the membrane 401 in deployment.

The (at least one) mesh of the body section 40 has two first apexes 505 that are generally opposite in the axial direction, and two pairs of second apexes 504 that are generally opposite in the circumferential direction. The spacing between the two pairs of second vertices 504 is approximately equal but less than the spacing between the two first vertices 505.

The long axis direction of the mesh of the main body section 40 is consistent with the axial direction of the support 404, the mesh can be elongated along the long axis direction, the radial shrinkage of the support 404 is realized, the axial expansion deformation can be well adapted, the controllable smooth shrinkage of the support 404 and the tectorial membrane 401 is completed, the shrinkage is smoothly completed after the expected operation is completed in vivo, and the external body is conveniently removed.

The maximum dimension of the mesh of the body section 40 in the axial direction is greater than the maximum dimension in the circumferential direction thereof. In other irregular polygonal holes, or spaces between non-vertices, the circumferential maximum dimension of the mesh of the body segment 40 is 1.2-3 times its axial maximum dimension. Two points providing a circumferential dimension are generally circumferentially opposite and two points providing an axial dimension are generally axially opposite.

The mesh of the body section 40 is a plurality of support meshes 50, the support meshes 50 being closed polygonal holes to form a stable support structure, stabilizing the pump gap. The supporting mesh 50 is at least two polygonal holes with unequal side lengths, and the polygonal holes can be irregular polygonal holes or polygonal holes with mirror symmetry structures, which is not limited in the application.

For example, the support mesh 50 is a mesh of mirror-symmetrical structure, and the length direction of the smallest edge is parallel to the axial direction, and includes two parallel first edges 501 and two parallel second edges 502. The second vertex 504 is located at least one end of the second edge 502 and the first vertex 505 is located at least one end of the first edge 501.

The support mesh 50 may be a quadrangular hole such as a diamond hole or a hexagonal hole.

In the diamond mesh embodiment, the support mesh 50 has two axial first peaks 505 forming front and

rear peaks

510a, 510b of a saw tooth configuration for the first and

second edges

501, 502, respectively. The two second peaks 504 are disposed opposite to each other in the circumferential direction, and the first and

second edges

501 and 502 form left and right tooth tops of a saw-tooth structure, respectively.

In the embodiment of hexagonal holes, the support mesh 50 further comprises two third edges 503 parallel to the axial direction. A third edge 503 is connected between a first edge 501 and a second edge 502, the first edge 501, the second edge 502, and the third edge 503 enclosing a closed hexagonal support mesh 50.

The third side edge 503 increases the axial dimension of the supporting mesh 50, so that the axial dimension of the supporting mesh 50 is the main dimension, and the supporting mesh can be smoothly folded along the axial direction when being taken into the sheath, and the resistance when being folded is reduced. Further, the length of the second edge 502 is equal to the length of the first edge 501, and the length of the third edge 503 is smaller than the length of the second edge 502. Third edge 503 is the smallest edge of support cell 50, providing the smallest edge of the cell.

The two axial end points of the third edge 503 form second vertexes 504, respectively, the axial rear end point of the third edge 503 is shared with a first edge 501, the shared end point forms a second vertex 504, the axial distal end point of the third edge 503 is shared with a second edge 502, and the shared end point forms another second vertex 504. The circumferential spacing of the two third edges 503 is the spacing of the two circumferentially opposite second vertices 504. The common end point of the first edge 501 and the second edge 502 forms a first vertex 505.

At least one of the first, second and

third edges

501, 502, 503 is a straight line edge, the multiple edges of the mesh form a polygonal mesh, and the whole edge is a straight line, which may be a straight line without bending as shown in fig. 11 and 12. Alternatively, the edges may be straight edges that allow some slight curvature and still be intuitively considered as polygons, as shown in fig. 13.

Thus, in the present application, the edges of the polygonal mesh are of generally rectilinear configuration.

The length of the first edge 501 ranges from 1mm to 2mm, the length of the third edge 503 ranges from 0.15mm to 0.35mm, and the ratio of the lengths of the first edge 501 and the third edge 503 ranges from 3:1 to 5:1. The first vertex 505 and the second vertex 504 are provided with a first and a second rounded structure, respectively, so that a smooth transition between the hole edges of the support mesh 50 is achieved, and a stable support structure is constructed. The arc length of the first rounded structure is greater than the arc length of the second rounded structure.

It is to be noted that the above-mentioned numerical values include all values of the lower value and the upper value that are incremented by one unit from the lower value to the upper value, and that there is at least two units of interval between any lower value and any higher value.

For example, the length of the first edge 501 is illustrated as ranging from 1mm to 2mm, preferably from 1.1 to 1.9mm, more preferably from 1.2 to 1.8mm, and even more preferably from 1.3 to 1.7mm, for purposes of illustration of the non-explicitly recited values such as 1.4mm, 1.5mm, 1.6mm, etc.

As mentioned above, the exemplary ranges given above in 0.1 interval units do not exclude increases in interval in appropriate units, e.g., in numerical units of 0.01, 0.02, 0.03, 0.04, 0.05, etc. These are merely examples that are intended to be explicitly recited in this description, and all possible combinations of values recited between the lowest value and the highest value are believed to be explicitly stated in the description in a similar manner.

Unless otherwise indicated, all ranges include endpoints and all numbers between endpoints. "about" or "approximately" as used with a range is applicable to both endpoints of the range. Thus, "about 20 to 30" is intended to cover "about 20 to about 30," including at least the indicated endpoints.

Other descriptions of the numerical ranges presented herein are not repeated with reference to the above description.

The plurality of support cells 50 are sequentially arranged in the circumferential direction to form support rings (50 a, 50b, 50 c), and the plurality of support rings are axially arranged to form the main body section 40. As shown in fig. 26, the first edges 501 and the second edges 502 are alternately arranged along the circumferential direction to form zigzag rings 520 having a zigzag structure, and two axially adjacent zigzag rings 520 are opposite to each other to form a supporting hole ring.

The body section 4050 has three

support collars

50a, 50b, 50c arranged in an axial direction. The serration rings 520 have front tooth tips 510a facing the inlet section 41 and rear tooth tips 510b facing the outlet section 42, the plurality of serration rings 520 being circumferentially arranged, the front tooth tips 510a of one serration ring 520 being axially opposed to the rear tooth tips 510b of the other serration ring 520 in adjacent two serration rings 520.

In this embodiment, the front tooth top 510a of one sawtooth ring 520 is connected (e.g. integrally formed or welded) with the rear tooth top 510b of the other sawtooth ring 520 along the axial direction by a third edge 503 parallel to the axial direction, so as to form a hexagonal supporting mesh 50. Accordingly, each support ring includes a plurality of circumferentially arranged hexagonal support cells 50.

In other embodiments, the front tooth top 510a of one sawtooth ring 520 is directly connected with the rear tooth top 510b of another sawtooth ring 520 in the axial direction to form a diamond-shaped support mesh 50. Accordingly, each support ring includes a plurality of circumferentially arranged diamond-shaped support cells 50.

As shown in fig. 23 and 25, the inlet section 41 is located on the front side of the main body section 40, at the distal end of the foldable stand 404, and the mesh of the inlet section 41 extends a longer length between the axial ends than the axial length of the support mesh 50.

The mesh of the inlet section 41 is an over-flow mesh for inflow of blood. The mesh of the inlet section 41 extends from the front end to the rear end of the mesh, and is not a radial projection length on the axis.

The axial length of the support mesh 50 in this embodiment is equal to its radial projected length on the axis.

The mesh of the inlet section 41 includes first and second through-

flow mesh holes

52a and 52b alternately distributed in the circumferential direction, and the length of the first through-flow mesh hole 52a is smaller than that of the second through-flow mesh hole 52 b. The first through-flow net hole 52a is a closed hole, and the second through-flow net hole 52 is a non-closed hole.

The distal end of the inlet section 41 is provided with a front connection 44. The front connection 44 is in a diverging or lobed configuration (split configuration) that can expand radially to facilitate the distal loading of the impeller 410 into the holder 404.

The front connection portion 44 includes a plurality of connection legs 45 dispersed in the circumferential direction, the connection legs 45 are in a T-shaped structure, leg gaps are provided between two adjacent connection legs 45, the leg gaps extend from the front connection portion 44 to the inlet section 41, and the inlet section 41 is also in a dispersed structure or a split structure.

Each first through-flow mesh 52a constitutes a flap body, and the inlet section 41 has a plurality of first through-flow mesh 52a spaced apart in the circumferential direction, and two adjacent first through-flow mesh 52a are spaced apart by a second filter mesh 52b. The connecting legs 45, when expanded radially outwardly, pull on (the edges of) the first flow-through web openings 52a, radially expanding the inlet section 41 together to facilitate assembly of the impeller 410.

The distal end of the connection leg 45 has a leg end 452 with a circumferential dimension larger than that of the leg rod body 451, the connection leg 45 can be clamped into a clamping groove 602 on the outer wall of the distal bearing chamber 6, the distal end of the clamping groove 602 is communicated with an annular groove 603, the leg rod body 451 of the connection leg 45 is clamped into the clamping groove 602, the leg end 452 is clamped into the annular groove 603, and the dispersed plurality of connection legs 45 are fixed on the distal bearing chamber 6 through the collar 61.

The distal bearing housing 6 has a stepped tubular structure with an insertion section 605 extending into the inlet section 41 of the holder 404 and a binding section 606 located outside the inlet section 41, with a variable diameter step 607 formed between the insertion section 605 and the binding section 606 as shown in fig. 17. The outer diameter of the extension 605 is smaller than the outer diameter of the restraint 606, creating a proximally directed reducing step 607.

A plurality of axially extending clamping grooves 602 are arranged on the outer wall of the binding section 606, and the clamping grooves 602 are parallel to each other and are circumferentially arranged. Preferably, the plurality of parallel clamping grooves 602 are uniformly distributed in the circumferential direction.

The depth of the clamping groove 602 does not exceed the height of the reducing step 607. Preferably, the depth of the clamping groove 602 is approximately equal to the (radial) projection height of the reducing step. Thus, the extension 605 facilitates folding of the stent 404, so that the stent 404 can be smoothly folded into the sheath.

The height of the connecting leg 45 does not exceed the card slot 602. That is, the height of the connection leg 45 is less than the depth of the clamping groove 602, and when the connection leg 45 is clamped into the clamping groove 602, the connection leg 45 does not exceed the wall surface of the constraint segment 606, so that the generation of extra protrusions is reduced.

The distal end of the clamping groove 602 opens into the annular accommodating groove 603, the leg rod body 451 clamps into the linear clamping groove 602, and the leg end 452 clamps into the annular groove 603. Preferably, the side of the leg end 452 is disposed in the annular groove 603, and to avoid forming a sharp structure, the side of the leg end 452 is an arc surface, the arc of which is equal to the arc of the outer wall of the restraint segment 606, or the radius of curvature of which is equal to the radius of the restraint segment 606.

The collar 61 is a cylindrical sleeve body, is fixedly sleeved outside the constraint section 606, and is used for binding the connecting support legs 45 in the clamping grooves 602 of the constraint section 606, so that the plurality of connecting support legs 45 are prevented from being ejected out of the clamping grooves 602.

In one embodiment, the cuff 61 is a heat shrink tube that is formed by heating. Specifically, after the connecting leg 45 is inserted into the clamping groove 602 and the annular groove 603, a heat shrinkage sleeve is sleeved outside the distal bearing chamber 6, a heating process is performed, the heat shrinkage sleeve is shrunk, and the connecting leg 45 is wrapped outside the distal bearing chamber 6 to form the collar 61.

The distal end of the distal bearing chamber 6 is provided with a spherical or rounded structure to facilitate non-invasive intervention in the body vessel. The distal end of the binding section 606 forms a stop step that stops the distal end of the cuff 61.

The distal bearing 62 is disposed in the extending section 605 of the distal bearing housing 6 to prevent the second shaft 355 from being separated from the distal bearing 62 when axially moving, and to maintain the rotation support state of the distal bearing 62 on the second shaft 355. The distal end of the second shaft 355 extends beyond the distal bearing 62 distally of the distal bearing 62.

In other embodiments, collar 61 and binding segment 606 may be secured by a threaded connection. Specifically, threads may be provided on the outer wall of the restraint section 606 to enable the attachment and detachment of the collar 61 by rotating the collar 61. Further, anti-rotation pins may be used to secure the collar 61 to the binding segment 606 to prevent relative rotation therebetween.

The pump body 4 is assembled by the following steps: s1, radially opening a plurality of connecting support legs 45; s2, penetrating the second shaft 355 and the distal bearing chamber 6 from the distal end of the bracket 404 to the proximal end thereof; s3, positioning the connecting support legs 45 in grooves on the outer wall of the distal bearing chamber 6; s4, the connecting support leg 45 is limited in the groove outside the distal bearing chamber 6 by sleeving the sleeve 61.

In step S1, the connecting legs 45 may be clamped by hand or by a clamp and pulled outwardly, so that the plurality of connecting legs 45 are radially expanded, and the front ports 46 of the front connection sleeve 1644 (the front ports 46 are circumferentially formed by the plurality of leg ends 452) are enlarged, thereby facilitating the insertion of the impeller 410.

During radial opening of the connecting leg 45, the connecting leg 45 pulls the first flow-through web 52a of the inlet section 41 to form a flap that opens together, facilitating placement of the impeller 410 and the second shaft 355 into the support 404. The second shaft 355 is threaded proximally until the proximal end of the second shaft 355 is threaded into the proximal bearing.

In step S2, the second shaft 355 and the distal bearing chamber 6 may be threaded sequentially or may be threaded synchronously (in a single motion). In a preferred embodiment, the second shaft 355 may be assembled with the distal bearing housing 6 and then moved together into the housing 404. Specifically, the distal end of the second shaft 355 is inserted into the distal bearing chamber 6, and then the plurality of connecting legs 45 are radially opened, and the second shaft 355 and the distal bearing chamber 6 are moved proximally from the distal end of the bracket 404. In this step, the impeller 410 is fixedly fitted over the second shaft 355. That is, the impeller 410 is sleeved on the second shaft 355 before the distal end of the second shaft 355 is inserted into the distal bearing chamber 6, and glue is applied between the hub 412 and the second shaft 355, and the impeller 410 is fixed on the second shaft 355 after the glue is cured.

In another embodiment, the second shaft 355 and the distal bearing chamber 6 are threaded sequentially. Specifically, after the plurality of connecting legs 45 are radially opened, the second shaft 355 is first inserted from the distal end of the bracket 404 to the proximal end thereof, and then the distal bearing housing 6 is fed from the distal end of the bracket 404 to the distal end surrounded by the plurality of connecting legs 45 and inserted by the second shaft 355. Wherein the distal bearing chamber 6 is assembled after the proximal end of the second shaft 355 is positioned through the proximal bearing.

In this assembly method, the plurality of connecting legs 45 are radially opened, the distal bearing housing 6 is fed into the plurality of connecting legs 45 and the receiving groove is aligned with the connecting legs 45, and the connecting legs 45 are placed in position in the receiving groove. The plurality of connecting legs 45 are put in the accommodating groove one by one while stopping when the distal bearing housing 6 is fed to a position surrounded by the plurality of connecting legs 45. In order to avoid the connection leg 45 from falling out of the receiving groove of the distal bearing chamber 6, a heat shrink sleeve is arranged outside the distal bearing chamber 6 and is heat shrunk to form a collar 61.

With the above description in mind, the occluding member 550 disposed within the distal bearing housing 6 is configured for threading of a guidewire. After the guidewire is withdrawn, the occluding component 550 resumes the occluded state. The blocking piece 550 can be made of blocking rubber or silica gel, when the guide wire passes through the blocking piece 550, the blocking piece 550 is attached to the guide wire to maintain a blocking state, and after the guide wire is withdrawn, the blocking piece 550 resets to close the wire through hole, and the blocking state of the position is still maintained.

The blocking member 550 is distal to the distal bearing 62 and distal to the distal end of the second shaft 355. The seal 5 is spaced from the distal end of the second shaft 355 to provide an axial play of the second shaft 355 for axial movement of the second shaft 355.

The second through-flow net hole 52b extends from the inlet section 41 to the front connection portion 44 until an opening 523 is formed at an end portion of the front connection portion 44, the opening 523 being formed between the two leg ends 452. A portion of the second through-flow apertures 52b are located in the inlet section 41 and a portion of the second through-flow apertures 52b are located in the front connection 44. The gap between the two connecting legs 45 constitutes a part of the second flow-through web 52b at the front connection 44, which is filled with the outer wall projection of the distal bearing chamber 6 during installation.

The circumferential width of the first through-flow web 52a gradually decreases as it extends from the front tooth top 510a toward the junction, and the front junction 525 or the first through-flow web 52a does not exceed the transition between the inlet section 41 and the connecting sub-pipe 43. The second through-flow mesh 52b includes a front section 521 whose circumferential width extends in the axial direction and a rear section 522 whose circumferential width extends in the axial direction in a direction away from the main body section 40, which becomes gradually smaller. Wherein the front section 521 is located at the front connection 44.

In the embodiment shown in fig. 25, the circumferential width of the aft section 522 is substantially constant as it extends in the axial direction. The circumferential width of the section (the rear side section 522) of the second through-flow net hole 52b located between the front tooth top 510a and the junction varies by less than 10% at different positions in the axial direction. The circumferential width of the rear section 522 is greater than or equal to the circumferential width of the front section 521, and there is a transition between the rear section 522 and the front region that is approximately at the transition between the inlet section 41 and the front connection 44.

Specifically, inlet section 41 includes a plurality of forward tensile ribs 528 extending from forward tooth top 510a toward forward connecting portion 44; the ends of adjacent front tensile ribs 528 distal from the main body section 40 meet to form a front junction 525; a plurality of front junctions 525 are connected to or extend to the connecting leg 45 in a one-to-one correspondence. The number of front tensile ribs 528 is equal to the number of front tooth tops 510a of one serration ring 520 and is 2 times the number of connecting legs 45.

The outlet section 42 is substantially similar to the inlet section 41 except that the third and fourth through-

flow mesh openings

51a, 51b are closed cells. Wherein the outlet section 42 is located at the proximal end of the collapsible bracket 404. The mesh of the outlet section 42 extends between the axial ends for a length greater than the axial length of the support mesh 50.

The mesh of the outlet section 42 includes third and fourth through-

flow mesh holes

51a and 51b alternately distributed in the circumferential direction, the third and fourth through-

flow mesh holes

51a and 51b being different in shape or area, and the length of the third through-flow mesh hole 51a being smaller than the length of the fourth through-flow mesh hole 51 b.

The proximal end of the outlet section 42 is provided with a connecting sub-tube 43, the connecting sub-tube 43 being fixed to the catheter 3 or the proximal bearing chamber by means of hot melt or glue, achieving proximal fixation of the support 404. The connecting secondary tube 43 may be provided with a locking hole 431 for locking the outer wall of the catheter 3 or the proximal bearing chamber 340.

A fourth through-flow mesh 51b extends from the outlet section 42 to the connecting sub-pipe 43 and forms a closed bore end at the connecting sub-pipe 43. A portion of the fourth through-flow apertures 512 are located in the outlet section 42 and a portion of the fourth through-flow apertures 511 are located in the connecting secondary pipe 43. The fourth through-flow net hole 51b does not extend to the rear end beyond the catching hole 431 of the connection sub-pipe 43.

The outlet section 42 includes a plurality of rear tensile ribs 518 extending rearwardly from the rear tooth top 510b, adjacent two rear tensile ribs 518 meeting proximally to form a rear junction. The plurality of rear junctions are connected to or extend to the rear spacer bars in a one-to-one correspondence as shown in fig. 25, and a portion of the fourth overcurrent net hole 511 located at the connecting sub-pipe 43 is formed between two adjacent rear spacer bars. The number of rear tensile ribs 518 is equal to the number of rear tooth tips 510b of an serrated ring 520 and is 2 times the number of connecting legs 45 or rear spacer bars.

The third through-flow web hole 51a gradually decreases in circumferential width as it extends from the rear tooth top 510b toward the rear junction, and the rear junction or the second through-flow web hole 52b does not exceed the transition between the outlet section 42 and the connecting sub-pipe 43. The circumferential width of the portion of the fourth through-flow mesh hole 51b located at the connecting sub-pipe 43 remains unchanged in the axial direction, and the rate of change in the circumferential width of the section of the fourth through-flow mesh hole 51b located between the rear tooth crest 510b and the rear intersection point at axially different positions is less than 10%.

Unlike the grid of the support 404 in fig. 25, the support 404 in fig. 23 has rear stretched ribs 518 of the outlet section 42 extending rearward without entering the connecting secondary tube 43. Accordingly, the third and fourth through-

flow apertures

51a, 51b are substantially distributed in the outlet section 42 of the bracket 404 and extend proximally beyond the transition between the outlet section 42 and the connecting secondary tube 43.

An outer flow path 600 is formed between the outer wall of the drive shaft 300 and the inner wall of the guide tube 3, and an inner flow path 800 is provided in the drive shaft 300 so as to be coextensive therewith. The outer flow path 600 has a first discharge port 608 at the distal end of the catheter 3, and the inner flow path 800 has a second discharge port 810 at the distal end of the drive shaft 300.

To slow down the flow rate of perfusate into the body, which is suitable for being accepted by the subject, the distal end of the inner flow channel 800 is provided with a diffuser section 820, and the end of the diffuser section 820 is provided with a second outlet 810. The diffuser section 820 has a flared shape with a gradually increasing cross-sectional area extending from its proximal end to its distal end.

As shown in fig. 1, at least one of the outer flow path 600 and the inner flow path 800 communicates with the perfusate input portion 20, and perfusate is input to the outer flow path 600 and the inner flow path 800 through the perfusate input portion 20.

The wall of the driving shaft 300 is provided with a communication portion for communicating the inner flow path 800 with the outer flow path 600, and the outer flow path 600 and the inner flow path 800 are spaced apart by the wall of the driving shaft 300 and communicate with each other by the communication portion.

By constructing the outer flow channel 600 and the inner flow channel 800 for delivering the perfusate to the distal end together, the multi-channel delivery of the perfusate is realized, and the perfusate input part 20 in the power transmission assembly is communicated with one of the outer flow channel 600 and the inner flow channel 800, so that the input structure can be simplified, the manufacturing is convenient, the flow area of the perfusate is increased through the communication part when the perfusate is input into one of the flow channels, the perfusion pressure is reduced, adverse effects caused by overlarge perfusion pressure are avoided, the perfusion flow is ensured, and the normal and smooth operation of the interventional operation is ensured.

The communication comprises a wall of the drive shaft 300 of at least part of the length within the conduit 3 through which liquid can permeate. The outer flow path 600 extends from the proximal end of the catheter 3 to the distal end of the catheter 3, the inner flow path 800 extends from the proximal end of the drive shaft 300 to the distal end of the drive shaft 300, and both the outer flow path 600 and the inner flow path 800 are continuous flow paths. The outer flow passage 600 has a substantially (circular) annular configuration in cross section. The cross-sectional shape of the inner flow passage 800 may be circular or polygonal, or even irregular. In the present embodiment, the cross-sectional shape of the inner flow path 800 is circular, the guide pipe 3 and the drive shaft 300 are substantially coaxially disposed in the straightened state of the guide pipe 3, and the cross-section of the outer flow path 600 is circular.

In this embodiment, the proximal end of the catheter 3 communicates with the perfusate input 20 to communicate the proximal end of the outer flow channel 600 with the perfusate input 20. The outer flow path 600 is a high pressure flow path, the inner flow path 800 is a low pressure flow path, and the perfusate is permeated into the inner flow path 800 through the wall of the driving shaft 300 by the pressure difference, and flows forward through the inner flow path 800 until entering the second discharge port 810. The proximal end of drive shaft 300 is occluded proximal of perfusate input 20. In this manner, leakage of the perfusate entering the drive shaft 300 proximally is avoided.

The perfusate input part 20 is a perfusate input port on the coupler 2, and the perfusate input port is communicated with an input runner. The perfusate input port 21 communicates with the lumen of the catheter 3 through an input flow channel, through which the drive shaft 300 passes, and provides a seal on the proximal side of the input flow channel (upstream of the power transmission direction) to avoid perfusate proximal leakage.

The coupler 2 is connected with the proximal end of the catheter 3, and a liquid flow passage is arranged between the catheter 3 and the driving shaft 300; the coupler 2 is further provided with a perfusion fluid inlet 21 communicating with the fluid flow path.

In operation of the catheter pump, heat is generated between relatively rotating components, such as the output shaft and drive shaft 300, and the drive shaft 300 and catheter 33, and heat build-up can increase wear of these components, reducing service life. Therefore, measures are necessary for thermal management.

In view of this, the catheter pump further comprises an irrigation channel extending substantially throughout the working assembly. In particular, the infusion channel runs through the drive shaft 300 to the transmission link of the pump body 4. When the catheter pump works, fluid can be injected into the perfusion channel, and the fluid is perfusion liquid (Purgeliquid) which needs to be perfused into a subject in the operation process of the catheter pump, and the perfusion liquid is for example, normal saline, glucose solution and anticoagulant which are injected into a body of the subject, or any combination of the above, so that the transmission link is lubricated and cooled.

The distal end of the coupler 2 is provided with a retaining sleeve 260 for the passage of the catheter 3, which retaining sleeve 260 may further act as a fixation for the catheter 3. The perfusate input 20 includes a perfusion flow channel (participating in forming a perfusion channel) provided on the coupler 2 and a perfusion port 201.

Specifically, the proximal inlet of the irrigation channel is an irrigation port 201 provided on the coupler 2. The lumen within coupler 2 may be filled with a fluid that lubricates and cools the proximal end of drive shaft 300. Therefore, the filling channel lubricates and cools the transmission link from the starting point of the transmission link of the working assembly, and effective work of the working assembly is ensured.

The present application is not limited to embodiments in which the outer flow channel 600 communicates with the perfusate input 20. In one possible embodiment, the inner flow channel 800 is communicated with the perfusate input part 20, the perfusate in the inner flow channel 800 flows radially outwards into the outer flow channel 600, specifically, the inner flow channel 800 of the driving shaft 300 is communicated with the perfusate input part 20 outside the body, the proximal end of the driving shaft 300 is connected with the output shaft of the motor through a connecting shaft, the output shaft and the connecting shaft are formed into a hollow structure, and the output shaft of the motor penetrates out from the tail end thereof to provide a perfusate input interface.

As shown in fig. 28 or 29, the driving shaft 300 includes a first shaft 350 and a second shaft 355 connected, and the second shaft 355 has a rigidity greater than that of the first shaft 350. The first shaft 350 is a flexible shaft, which may also be referred to as a flexible shaft, to facilitate penetration into a vessel to accommodate bending of the vessel structure, and to deliver the distal pump assembly to a desired location. The second shaft 355 is a rigid shaft, also referred to as a hard shaft, an impeller shaft, and cooperates with the proximal 331, 332 and distal 4501 bearings on either side to provide stable support for the impeller 410, allowing the impeller 410 to be positioned in the pump housing 363 to achieve a desired stability.

The proximal end of the first shaft 350 passes out of the catheter 3 and is connected to the output shaft of the motor by a connecting shaft. The second shaft 355 is fixedly sleeved by the impeller 410. The impeller 410 has blades 411 and a hub 412, and the hub 412 is fixedly sleeved on the second shaft 355 and is driven to rotate by the second shaft 355.

The connection location of the stent 404 to the catheter 3 is located proximal to the second shaft 355. The proximal end of the bracket 404 is provided with a connection secondary pipe 43, and the catheter 3 is connected with the connection secondary pipe 43 in a hot melt or snap connection manner. Alternatively, the catheter 3 is connected to the connection sub-tube 43 via the proximal bearing chamber 330, possibly by bonding the distal end of the catheter 3 to the proximal bearing chamber 330 and by snap-fitting the connection sub-tube 43 to the proximal bearing chamber 330.

As described above, the second shaft 355 passing through the hub 412 is a hard shaft and is not subject to bending deformation in order to provide sufficient strength support to the impeller 410 so that it is stably held in position within the pump casing 363. Thus, in order not to have the stiffer second shaft 355 affect the bending properties of the working part of the front end of the blood pump (including the pump assembly and the part of the front end catheter 3 that is to be introduced into the human body), the proximal end of the second shaft 355 is located inside the proximal end of the stent 404 or inside the connecting sub-tube 43, but does not protrude out of the connecting sub-tube 43. That is, the proximal end of the second shaft 355 is positioned within the connecting sub-tube 43 and does not extend beyond the connecting sub-tube 43.

In the scenario where the pump assembly is introduced in a collapsed manner, the collapsed pump assembly is relatively rigid and generally inflexible. Then, during the intervention, the over-bending of the pump assembly needs to be effected by means of the bending of the catheter 3 connected thereto. Through the above design, the proximal end of the second shaft 355 is located inside the proximal end of the bracket 404 or inside the connecting sub-tube 43, so that the proximal end of the second shaft 355 does not extend out of the connecting sub-tube 43 and enter the catheter 3 too much, and therefore, the rigidity of the catheter 3 cannot be increased due to the gain effect of the second shaft 355, and the distal end portion of the catheter 3 connected with the connecting sub-tube 43 still maintains better flexibility, so as to ensure the overstretching performance of the pump assembly during the intervention.

The distal end of the first shaft 350 and the proximal end of the second shaft 355 are connected by means of a socket, such as a non-circular cross-sectional configuration, allowing axial relative movement between the first shaft 350 and the second shaft 355 and transmitting rotation. For example, the first shaft 350 has a rectangular female socket and the second shaft 355 has a rectangular male plug, with the two being coupled by way of the two being coupled to one another to permit axial relative movement and to transmit rotation.

The communication extends from the proximal end of the first shaft 350 to the distal end of the first shaft 350. The first shaft 350 is woven with a liquid permeable structure in the wall and the communication is a woven slit extending through the wall of the first shaft 350. The first shaft 350 is a multi-layer woven structure, e.g., a layer-by-layer wrap of 2, 3, 4, or more layers.

The plurality of braid layers of the first shaft 350 are in a layer-by-layer nested relationship, the braid layers being woven helically. Wherein the spiral directions of two adjacent braiding layers are opposite. The multi-layer braiding structure is a spiral twisting structure, and the rotation directions of the inner and outer adjacent braiding layers are opposite.

By providing the first shaft 350 with a braided twisted structure having opposite sense of rotation of the adjacent inner and outer braided layers, a spiral groove or protrusion is formed on the outer surface of the first shaft 350, which spiral groove or protrusion has opposite sense of rotation of the driving shaft 300, so as to create a pumping effect, pump the perfusate distally, and prevent blood from entering at the distal end of the catheter 3, avoiding thrombus formation at the distal end of the catheter 3.

The communication portion extends over the circumferential direction and the axial direction of the first shaft 350, and connects the outer flow path 600 and the inner flow path 800 by a fluid-permeable manner, and the wall of the drive shaft 300 at least partially located in the conduit 3 is a fluid-permeable structure. The first shaft 350 is entirely of a liquid permeable structure, and the wall of the portion of the first shaft 350 covered by the conduit 3 constitutes a communication portion where the inner flow path 800 and the outer flow path 600 communicate. The connection between the inner flow path 800 and the outer flow path 600 extending to the first shaft 350 and the second shaft 355 is always in fluid communication or fluid penetration.

The outer wall of the first shaft 350 included in the driving shaft 300 is formed with a spiral structure, which may be a spiral protrusion or a spiral groove, and the spiral direction of the spiral structure is opposite to the rotation direction of the driving shaft 300. The helical structure is left-handed when the drive shaft 300 is rotated clockwise, as viewed from the proximal to distal direction. Alternatively, in the case where the driving shaft 300 is rotated counterclockwise, the screw structure is a right-handed screw.

In this embodiment, the perfusion fluid first flows forward in the outer flow channel 600, i.e. inside the catheter 3 or outside the first shaft 350. During flow, a portion of the perfusate seeps into the first shaft 350, i.e., the inner flow channel 800. The spiral structure of the outer wall of the first shaft 350 forms a pump effect when rotating, and can generate forward force on the perfusate in the external flow channel 600, so that the perfusion flow is smooth, and the perfusate congestion is avoided.

For the same purpose, the inner wall of the first shaft 350 may also be formed with such a spiral structure in order to provide continuous forward flow of the perfusate in the inner flow channel 800.

The helical structure formed by the outer and/or inner walls of the first shaft 350 may be formed by the helical braid described above. The braid is typically spiral braided from a single strand of material that is generally circular in cross-section to naturally form the spiral protrusions or grooves in the braid. Wherein the protrusions are the outer contour of the single strand of material and the grooves are formed between the woven materials.

Therefore, in order to achieve the above-described spiral structure on the outer wall of the first shaft 350, in the case where the first shaft 350 adopts the spiral braid structure, it is only necessary to make the spiral direction of the outermost braid opposite to the rotation direction of the first shaft 350.

Likewise, the spiral direction of the innermost braid is opposite to the rotation direction of the first shaft 350, and it is possible to form a spiral structure conforming to the above description on the inner wall of the first shaft 350. That is, when the drive shaft 300 is rotated clockwise as viewed from the proximal end toward the distal end, the spiral structure on the innermost braid is left-handed. Alternatively, in the case where the driving shaft 300 is rotated counterclockwise, the spiral structure on the innermost braid is a right-handed thread.

Thus, the spiral direction of the innermost and outermost braid is the same. In the case where the spiral directions of adjacent braid are reversed as set forth above, the number of braid layers included in the first shaft 350 should be an odd number of layers greater than 1, such as 3 layers or 5 layers.

Further, since the first shaft 350 needs to transmit torque, the outermost spiral braid tends to be tightened due to the torque in the rotation process by virtue of the structural design that the spiral direction of the outermost braid is opposite to the rotation direction of the first shaft 350, so that the outermost braid is prevented from loosening.

Thus, during rotation, the diameter of the braid, which is in the opposite direction of rotation of the first shaft 350, tends to decrease. If all of the spiral braid of the first shaft 350 is rotated in the opposite direction to the first shaft 350, the diameter of the first shaft 350 cannot be stably maintained as the working time is extended.

As described above, there are two adjacent braid layers in the first shaft 350 that are opposite in spiral direction. That is, the first shaft 350 includes a braid having a spiral direction identical to that of its rotation, which tends to increase in diameter or to loosen during rotation due to torque.

Then, the braid having the spiral direction opposite to the rotation direction of the first shaft 350 applies an inward compressive force to the inner braid, and the braid having the spiral direction identical to the rotation direction of the first shaft 350 applies an outward expansive force to the outer braid. Thereby, the diameter variations or forces of adjacent braid are at least partially compensated for, thereby allowing the diameter of the first shaft 350 to be stably maintained.

The stable maintenance of the diameter of the first shaft 350 is advantageous in that the shape of the outer flow path 600 is stable, thereby stabilizing the flow rate and the flow area of the perfusate.

The above-described arrangement of forming a helical structure by means of the helical braid configuration of the first shaft 350 is illustrative and not limiting in uniqueness. That is, in other alternative embodiments, it is also possible that the outer wall and/or the inner wall of the first shaft 350 is a flat or smooth wall, for example, on which the above-described spiral structure is formed by machining a spiral groove or protrusion.

The connection between the distal end of the first shaft 350 and the proximal end of the second shaft 355 is located within the distal end of the catheter 3, and the two may be connected by any suitable means, such as welding, although the two may be connected by other driving connections, such as splines, so long as the two are capable of driving rotation.

As shown in fig. 18, the second shaft 355 has an exposed portion 3556 with a wall surface exposed in the bracket 404, and a first spiral structure 3558 is provided on at least a portion of the wall surface of the exposed portion 3556. First helical structure 3558 is located distally of hub 412 and may be a helical groove or a helical protrusion.

The first helical structure 3558 rotates in the same direction as the second shaft 355. Viewed from the proximal to distal direction, the first helical structure 3558 is right-handed in the case of clockwise rotation of the second shaft 355, or the first helical structure 3558 is left-handed in the case of counterclockwise rotation of the second shaft 355. The first helical structure 3558 creates a pumping effect during rotation that provides a driving force to the blood in the same direction as the impeller 410, pumping the blood within the pump housing 363, thereby preventing reverse flow of blood into the distal bearing chamber 6, avoiding hemolysis and thrombosis.

The second shaft 355 has a first non-exposed portion 3555 that is nested within the hub 412. In order to improve the connection strength between the second shaft 355 and the impeller 410 and avoid the detachment problem between the impeller 410 and the second shaft 355, at least part of the wall surface of the first non-exposed portion 3555 is provided with a concave structure 3554.

The recess 3554 is provided on the outer wall of the second shaft 355, and may have various forms, such as a groove structure, discrete dot-shaped grooves, a long groove structure, etc. The recessed structures 3554 can increase the adhesive area and improve the connection strength between the hub 412 and the second shaft 355.

In one embodiment, the recessed feature 3554 is a spiral groove feature that forms a continuous spiral groove feature with the first spiral feature 3558. That is, the continuous helical groove structure extends from inside the hub 412 to outside the hub 412

The second shaft 355 has a second non-exposed portion 3557 that is sleeved in the distal bearing chamber 6, and a second helical structure 3559 is provided on at least a portion of the wall surface of the second non-exposed portion 3557. The second helical structure 3559 may be a helical groove or a helical protrusion, the helical direction being the same as the rotational direction of the second shaft 355. The second helical structure 3559 is right-handed when the second shaft 355 is rotated clockwise, or the second helical structure 3559 is left-handed when the second shaft 355 is rotated counterclockwise, as viewed from the proximal to distal direction.

Likewise, the second helical structure 3559 creates a pumping effect during rotation that provides a driving force to the blood in the same direction as the impeller 410, preventing blood from flowing in a reverse direction into the distal bearing chamber 6, avoiding hemolysis and thrombosis.

The recessed structures 3554, the spiral structures 3558, and the spiral structures 3559 can form a continuous spiral groove structure. That is, the distal side wall surface of the second shaft 355 is provided with a continuous spiral groove structure, the portion of the continuous spiral structure in the hub 412 forms the recess structure 3554, the portion in the bracket 404 forms the spiral structure 3558, and the portion in the distal bearing chamber 6 forms the spiral structure 3559.

As described above, the continuous spiral structures (3554, 3558, 3559) achieve corresponding technical effects at three different positions, and will not be described again.

The direction of rotation of the continuous spiral structure (3554, 3558, 3559) is the same as the direction of rotation of the second shaft 355. The continuous spiral structure is right-handed when the rotation of the drive shaft 300 is clockwise, or left-handed when the rotation of the drive shaft 300 is counterclockwise, as viewed from the proximal end toward the distal end.

The continuous helical structure (3554, 3558, 3559) on the second shaft 355 has a beginning starting at the proximal end of the hub 412 and a stopping end at the distal end (substantially port location) of the second shaft 355, thereby presenting different sections that are obscured, exposed, and re-obscured in the direction of power transfer. The depth of the spiral groove is 0.05-0.2mm.

The communication portion extends over the circumferential and axial directions of the first shaft 350, and connects the outer flow path 600 and the inner flow path 800 by a fluid-permeable manner, and the wall of the drive shaft 300 at least partially located in the conduit 3 is a fluid-permeable structure. The first shaft 350 is entirely of a liquid permeable structure, and the wall of the portion of the first shaft 350 covered by the conduit 3 constitutes a communication portion where the inner flow path 800 and the outer flow path 600 communicate. The connection between the inner flow path 800 and the outer flow path 600 extending to the first shaft 350 and the second shaft 355 is always in fluid communication or fluid penetration.

The connection portion of the first shaft 350 and the second shaft 355 is located between the proximal end bearing chamber 340 of the proximal end bearing chamber 340 and the second shaft 355 to form a communication path that communicates the outer flow passage 600 and the first exhaust port 608.

A proximal bearing chamber 340 is located at the distal end of the catheter 3, within which is located a first proximal bearing 331 and a second proximal bearing 332 located distally of the first proximal bearing 331. In other embodiments, the proximal bearing is not excluded from one or more. The

proximal bearings

331, 332 are sleeved outside the second shaft 355, and the first exhaust port 608 is located distally of the proximal bearing 332.

As shown in fig. 19 and 20, the outer wall of the drive shaft 300 is provided with a stopper 356 axially movably located between the

proximal bearings

331, 332, and the stopper 356 is a stopper ring provided on the outer wall of the drive shaft 300 or a stopper protrusion such as a bump provided on the outer wall of the drive shaft 300.

A stop flow gap is formed between the outer wall of the stop 356 and the inner wall of the proximal bearing chamber 340. The first exhaust port 605 is located distally of the second proximal bearing 332. The communication path includes a first proximal bearing 331 internal flow gap, a stop flow gap, and a second proximal bearing 332 internal flow gap. Wherein the first and second

proximal bearings

331, 332 themselves have flow gaps that are permeable to fluid and do not seal against fluid passage.

Of course, a first flow gap may also be formed between the first proximal bearing 331 and the outer wall of the second shaft 355, and a third flow gap may be formed between the second proximal bearing 332 and the outer wall of the second shaft 355, further facilitating fluid flow.

The stopper 356 and the first proximal bearing 331 have a first spacing therebetween, which communicates the stopper flow gap with the first proximal bearing 331. The stopper 356 and the second proximal bearing 332 have a second spacing therebetween, and the stopper flow gap communicates with the second proximal bearing 332.

A tortuous perfusate output path is constructed by the first proximal bearing 331, stop flow gap and second proximal bearing 332, slowing perfusate flow rate and impact pressure, avoiding damage or other adverse effects from rapid entry into the subject.

In some other embodiments, the proximal bearing housing 340 for mounting the

proximal bearings

331, 332 may be replaced by other structures, such as a distal portion of the catheter 3 or the connecting hypotube 43 of the stent 404. In this embodiment, the proximal bearing housing 340 may be eliminated and the

proximal bearings

331, 332 mounted within the distal end of the catheter 3 or within the connecting sub-tube 43.

Thus, the proximal bearing chamber 340 for mounting the

proximal bearings

331, 332, the distal portion of the catheter 3 or the connecting sub-tube 43 may constitute a proximal bearing mounting member. Alternatively, the proximal bearing mounting means comprises a proximal bearing housing 340, a distal portion of the catheter 3 or the connecting sub-tube 43, the present application is not limited solely by the additional provision of a distal bearing housing 6.

The distal end of the second shaft 355 is rotatably supported within the distal bearing housing 6, and the distal end of the bracket 404 is connected to the distal bearing housing 6. The second discharge port 810 is located in the distal bearing housing 6, and forms a perfusate discharge port between the proximal end of the distal bearing housing 6 and the drive shaft 300. A flow gap is formed between the distal bearing 62 and the drive shaft 300 (second shaft 355).

As shown in fig. 17, the occluding component 550 is positioned between the distal end of the second shaft 355 and the proximal end of the atraumatic support 5. Thus, the perfusate in the inner flow channel 800 is discharged from the second discharge port 810 into the distal bearing chamber 6, flows only in reverse due to the presence of the blocking member 550, and then flows through the distal bearing 62 to lubricate it, and then is discharged from the perfusate discharge port out of the distal bearing chamber 6 into the support 404 and finally into the human body. Thus, the perfusate discharged from the perfusate discharge port can form a high pressure area within a certain range at the proximal end of the distal bearing chamber 6, thereby preventing the hemostatic liquid from entering the distal bearing chamber 6 and preventing thrombus formation.

The occluding member 550 is a flexible check valve, such as a check valve, provided with a resealable channel through which the guidewire may pass, the resealable channel being closed upon removal of the guidewire threading to maintain the occluded state of the site. The flexible hemostatic valve can be made of plugging rubber or silica gel, when the guide wire passes through the resealable channel, the flexible hemostatic valve is attached to the guide wire to maintain a plugging state, and after the guide wire is withdrawn, the flexible hemostatic valve resets to close the wire penetrating hole, and the plugging state of the position is still maintained.

The blocking member 550 may constitute an axial stop for the second shaft 355, defining a far dead center position of the axial movement of the blocking member 550. Of course, in the presence of the stop 356 described above, the distal end of the second shaft 355 is not in contact with the closure member 550 when the stop 356 is in contact with the second proximal bearing 332, and is spaced apart to avoid damage to the closure member 550 by axial movement of the second shaft 355.

As shown in fig. 1, 21, 22, in some embodiments, no plug 500 may be provided between the second outlet port 810 and the atraumatic support 500, with the interior of the distal bearing chamber 6 communicating the second outlet port 810 with the hollow lumen 555. The distal port of the atraumatic support 500 constitutes a perfusate discharge outlet. At this time, since the perfusate pressure is high, the distal bearing 4051 may also form a perfusate discharge path, forming a perfusate discharge port on the proximal side of the distal bearing 4051, at which time perfusate may be discharged out of the distal port of the atraumatic support 500 and the proximal side of the distal bearing 4051 at the same time.

The perfusate exits through the second discharge port 810 and enters the non-invasive support 500 and exits proximally of the distal port of the non-invasive support 500 and distal bearing 4051, while blood is prevented from entering the non-invasive support 500 and distal bearing chamber 6 in the operating state of the pump assembly.

With the above description, the pump body 4 is folded by using the sheath, and the specific folding scheme is that the sheath is pushed forward, and the pump is forcedly folded by axial movement. In this way, the sheath exerts a significant axial force between the stent 404 and the catheter 3. This requires a high bonding strength between the stent 404 and the catheter 3. Otherwise, it is very easy for the sheath to lift the pump off the catheter 3.

On the other hand, the curved path through which the interventional procedure is performed requires a better bending of the entire catheter 3 assembly, including the connection of the stent 404 to the catheter 3.

With the above description in mind, the proximal end of the stent 404 is provided with a connecting hypotube 43 which connects to the distal end of the catheter 3. In this embodiment, the connection location of the stent 404 to the catheter 3 is located proximal to the hard shaft 355 (second shaft 355), the proximal end of the hard shaft 355 being located within the connection sub-tube 43 and not extending out of the connection sub-tube 43. In this manner, increasing the flexibility of the portion of the connecting secondary tube 43 proximal to the hard shaft 355 may increase the over-bending performance of the catheter 3 assembly.

As shown in fig. 29 and 31, the connecting sub-tube 43 at the proximal end of the bracket 404 is provided with a joint extending through at least a part of the wall thickness thereof. The joint portion exhibits a concave structure on the connection sub-pipe 43 to form an accommodation space. The distal end of the catheter 3 is provided with a hot melt cure formed bonding material received in the bonding portion.

In the present embodiment, a proximal bearing 330 for supporting the drive shaft 300 is provided in the connection sub-tube 43, and the connection sub-tube 43 is configured as a proximal bearing mounting member. The proximal bearing 330 is directly arranged in the connecting secondary pipe 43, and is positioned by a positioning part arranged on the connecting secondary pipe 43, so that a proximal bearing chamber is not required to be additionally arranged, the number of superposed layers of the part is reduced, and the bending performance is improved.

In one possible embodiment, the connection sub-tube 43 is sleeved outside the distal end of the catheter 3. The outer part of the connecting secondary pipe 43 is sleeved with an intermediate connecting sleeve 16. The intermediate connecting sleeve 16 and the connecting secondary pipe 43 and the guide pipe 3 are of a split structure. The connecting secondary pipe 43 is connected to the catheter 3 by an additional intermediate connection sleeve 16. The joint material is formed by hot melting and then curing the intermediate connecting sleeve 16. The connecting secondary tube 43 is provided with a junction extending through at least part of the wall thickness thereof, the junction containing therein a junction material which flows into the junction after being melted and solidified, the junction material being provided at the distal end of the catheter 3, and being provided by the intermediate connection sleeve 16.

Part of the intermediate connecting sleeve 16 is located proximally of the connecting secondary tube 43 and fixedly sleeved outside the catheter 3. Specifically, part of the intermediate connecting sleeve 16 is adhered and sleeved on the outer wall of the conduit 3 after hot melting, or part of the intermediate connecting sleeve 16 is adhered on the outer wall of the conduit 3, or the outer wall of the conduit 3 is provided with a caulking groove for accommodating an embedded protrusion formed by solidifying part of the intermediate connecting sleeve 16 after hot melting.

In the present embodiment, the portion of the intermediate connecting sleeve 16 and the guide pipe 3 may be connected by heat fusion or the like, and the present embodiment is not particularly limited. Of course, the connection mode of the intermediate connecting sleeve 16 and the catheter 3 may also refer to the connection mode of the jointing material and the jointing portion, which is not described herein.

With continued reference to the embodiments shown in fig. 28, 29, and 31. In the present embodiment, the joining material is a structure in which a part of the catheter 3 is formed by hot melt curing or hot press forming. The jointing material is heated to soften the far end pipe wall of the conduit 3 during hot press molding, and the softened pipe wall of the conduit 3 is formed into local convex deformation by a pressing tool, and is embedded into the jointing part inwards, and the jointing material is formed after cooling and solidifying.

The melting point of the bonding material is the same as or similar to the melting point of the material of the catheter 3. The material of the joint material is the same as that of the duct 3, or the joint material and the duct 3 are both resin materials. The bonding material is similar or identical to the main material of the catheter 3.

In order to increase the strength of the joint between the catheter 3 and the stent 404 without losing the bending properties of the catheter 3 assembly, the proximal end of the stent 404 is provided with a first connection 421 for connecting the catheter 3. The distal end 301 of the catheter 3 is provided with a second connection 321. One of the first connecting portion 421 and the second connecting portion 321 is provided with a connecting protrusion 323, and the other is provided with a limiting recess which is in embedded fit with the connecting protrusion 323. The limiting recess limits and fixes the embedded connecting protrusion 323 at least axially. Further, the limiting recess performs limiting fixation in the axial and circumferential directions on the connection protrusion 323. That is, the limit recesses are connected with the connection protrusions 323, thereby achieving connection of the catheter 3 and the stent 404.

The first connection portion 421 and the connection sub-pipe 43 are integrally formed, that is, the first connection portion 421 is integrally formed on the connection sub-pipe 43. The second connecting portion 321 is integrally formed with the catheter 3, i.e., the second connecting portion 321 is integrally formed with the distal end 301 of the catheter 3. The second connecting portion 321 is a snap projection (connecting projection 323) projecting radially inward. The connection protrusion 323 is formed by thermal fusion curing. In addition, the connection protrusion 323 may be formed by hot press molding.

The wall surface area of the first connection portion 421 is smaller than the side area of the cylinder with the same axial length and diameter. In this embodiment, the limiting recess is a recess structure provided on the connection sub-pipe 43. The limiting recess is recessed radially, and a female buckle is formed at one axial side, so that the connecting protrusion 323 is axially limited.

The concave structure is a through hole structure and can also be a groove structure. In this embodiment, the recess is a through hole penetrating the wall of the connecting secondary pipe, and specifically, the limiting recess penetrates the wall of the connecting secondary pipe in the radial direction. The recess is a connection hole 435. The first connection portion 421 has a plurality of connection holes 435, the plurality of connection holes 435 are arranged in an axial direction, and the plurality of connection holes 435 are parallel to each other. The proximal hole wall of the connecting hole 435 in the axial direction constitutes a pin. The connection sub-pipe 43 is made of memory alloy, and further can be provided with a female hole (connection hole) made of metal for the connection protrusion 323 of the conduit 3 to be snapped in as a male buckle.

The connection hole 435 has a long hole structure, and a length direction thereof extends in a circumferential direction. The connecting aperture 435 corresponds to a central angle greater than 180 degrees. The two ends of the connecting hole 435 in the circumferential direction are disposed opposite to each other at intervals. The connection hole 435 has a first hole end 4351 and a second hole end 4352 in the circumferential direction. The first and

second ends

4351, 4352 are spaced apart.

The two adjacent connecting holes 435 are at least partially staggered in the axial direction. Two adjacent connecting holes 435 are at least partially overlapped in the axial direction. Therefore, the first connecting portion 421 has reduced material consumption while maintaining its structural strength, and the connecting portion has better flexibility. The two adjacent connecting holes 435 are staggered, so that the connecting part for connecting the secondary pipe 43 and the guide pipe 3 has better axial tensile failure resistance and avoids the sheath pipe from disconnecting the pump body 4 from the guide pipe 3.

A hole spacing portion 437 is provided between adjacent two of the connection holes 435. The hole spacing portion 437 extends continuously in the circumferential direction, separates the two connecting holes 435 from each other, and forms a closed connecting hole 435, that is, the connecting hole 435 is a closed hole, and the hole wall extends continuously to form a closed circumferential long hole. The axial width of the hole spacing portion 437 is not smaller than the axial width of the connection hole 435.

The connecting holes on two axial sides of a connecting hole are aligned, as shown in fig. 24, a connecting hole 435c is formed between the connecting hole 435a and the connecting hole 435b, wherein the connecting hole 435c is offset from the connecting hole 435a and the connecting hole 435b, the connecting hole 435a is aligned with the hole end of the connecting hole 435b in the axial direction, and the space between the two connecting

holes

435a and 435b is centered with respect to the connecting hole 435 c.

An end spacer 436 is provided between the first bore end 4351 and the second bore end 4352. The end spacer 436 has a length in the circumferential direction that is greater than the width of the connection hole 435 in the axial direction. The circumferential length (length in the circumferential direction) of the end spacer 436 is smaller than the circumferential length of the connection hole 435. The axial projection of the end spacer 436 is entirely located adjacent the connection aperture 435. The first and second bore ends 4351 and 4352 have a chamfer configuration,

the lengths of the adjacent two connection holes 435 may be equal or different. In this embodiment, the lengths of the plurality of connection holes 435 are equal, and two adjacent connection holes 435 are staggered to form a hole structure staggered on the connection sub-pipe 43.

Adjacent two of the connection holes 435 have overlapping portions in the axial direction. Wherein, the circumferential length of the overlapping portion 4355 is greater than the width of the connection hole 435 in the axial direction. As shown in fig. 23 and 24, the connecting hole 435 has overlapping portions 4355 on both circumferential sides of the end gap 436, and the overlapping portions 4355 are formed in mirror symmetry.

A connecting hole 435 is spaced between adjacent two end-to-end spacers 436. In the axially extending embodiment, the adjacent two connecting holes 435 have overlapping portions 4355 in the circumferential direction, but may have offset portions. The overlapping portions 4355 on both sides of the end spacer 436 are a first overlapping portion and a second overlapping portion, which are mirror-symmetrical to each other. The end spacer 436 and the first overlap portion or the second overlap portion have substantially equal circumferential lengths. In the present embodiment, the total length of the end spacer 436, the first overlap portion, and the second overlap portion in the circumferential direction is approximately half the circumference.

The connection secondary tube at the proximal end of the support 404 is provided with a plurality of connection holes 435, which can provide deformation avoidance space for the support 404 on the one hand, so that the support 404 has better flexibility. On the other hand, the molten material of the catheter 3 is easy to enter the connecting hole 435, the joint area of the catheter 3 and the bracket 404 is increased, and an axial stop or fixing structure is formed between the catheter 3 and the bracket 404, so that the connection strength of the catheter 3 and the bracket 404 in the axial direction is at least improved.

Further, the first connection portion 421 and the second connection portion 321 are also fixed by adhesion. The second connection portion 321 further has an adhesion surface to which the first connection portion 421 adheres. The second connection portion 321 is cured by hot melt to form an adhesive surface. The bonding structure for bonding the first connection portion 421 and the second connection portion 321 is formed by heat-fusing the first connection portion 421.

Specifically, the proximal connecting sub-tube 43 of the stent 404 is provided with a plurality of connecting holes 435 for insertion into the wall-pinching receptacles of the distal end 301 of the catheter 3. The catheter 3 material is flowed into the opening by a thermal fusion technique to integrate the catheter 3 with the stent 404. The proximal bearing 330 is provided in the connection sub-tube 43 of the bracket 404 or the proximal bearing chamber is provided in the connection sub-tube 43 or the proximal bearing chamber of the bracket 404, and the proximal bearing 330 is provided in the connection sub-tube 43 or the proximal bearing chamber for the driving shaft 300 to pass through.

In other embodiments, the connection aperture 435 may also be a helical aperture extending helically at the proximal end of the connection hypotube 43. Of course, the connection sub-pipe 43 may be provided with a single screw connection hole, or a plurality of connection holes may extend in parallel screw. Alternatively, the connecting hole is an axially extending long hole; the plurality of elongated holes are arranged in the circumferential direction.

The limiting recess is also not limited to a hole-like structure, and in one possible embodiment, the first connecting portion 421 is provided with a hook-like structure having a generally circumferentially extending hooked edge at the proximal end of the hook-like structure that is axially contact-limited with the projection of the second connecting portion 321, maintaining engagement. When the support 404 is pushed to the distal end by the sheath, the hooking edge of the first connecting portion 421 and the protrusion of the second connecting portion 321 form a hooking structure, so that the support 404 is prevented from being separated from the sheath, and the support 404 can be folded into the sheath.

Alternatively, holes of different shapes may be distributed in the connecting secondary walls. The connecting hole can also be an irregular hole, and only the structure of the protrusion 323 can be connected to form axial mechanical contact limit, so that the catheter 3 and the support 404 form a more stable connecting structure, the support 404 is prevented from being pushed and separated by the sheath tube because of being unable to be folded, and the pump body 4 is ensured to be smoothly retracted into the sheath tube.

In a possible embodiment, the distal end 301 of the catheter 3 and the proximal end of the stent 404 may also be connected by an intermediate connection sleeve 16. Wherein the distal end 301 of the catheter 3 is connected to the intermediate connection sleeve 16 and the second connection 321 is located on the intermediate connection sleeve 16. The proximal end of the intermediate connection sleeve 16 is fixedly sleeved on the distal end 301 of the catheter 3, and the distal end 301 of the intermediate connection sleeve 16 is fixedly sleeved on the proximal end of the bracket 404. Wherein the distal end 301 of the catheter 3 is provided with a coupling hole such as described above, and correspondingly, the proximal end of the stent 404 is provided with a coupling hole such as described above, and the intermediate connection sleeve 16 is formed with a protrusion inserted into the coupling hole by heat fusion while connecting the catheter 3 and the stent 404, so that the intermediate connection sleeve 16 forms not only a mechanical hooking structure with the distal end 301 of the catheter 3, but also a mechanical hooking structure with the proximal end of the stent 404.

The second connecting portion 321 is sleeved outside the first connecting portion 421, the second connecting portion 321 is melted by hot melting, and the material of the conduit 3 in the melted state flows into the connecting hole of the first connecting portion 421 to be cooled and solidified to form the connecting protrusion 323, so that the first connecting portion 421 and the second connecting portion 321 are connected. Of course, the second connecting portion 321 still has a sleeve structure in the hot-melt state, and the ring is sleeved outside the second connecting portion 321 (connected to the proximal end of the secondary tube), part of the material flows into the connecting hole to be cooled to form the connecting protrusion 323, and the second connecting portion 321 and the first connecting portion 421 also form an adhesive structure after being hot-melt cooled.

The pipe 3 is used for carrying out hot melting to form a mechanical hooking structure and a chemical bonding structure without arranging other connecting structures, so that the bonding strength between the pipe 3 and the bracket 404 can be improved, the bending performance of the pipe 3 assembly is not lost, and the bending performance of a connecting part can be enhanced.

Further, the distal end 301 of the catheter 3 further has a third connecting portion 322 formed on a radially inner side of the first connecting portion 421 and made of the same or similar material as the second connecting portion 321. The material of the guide tube 3 generated by melting the second connection portion 321 enters into the connection hole and passes through the connection hole to be in contact with the third connection portion 322.

The third connecting portion 322 is located at the innermost side, and the melted catheter 3 material and the third connecting portion 322 form a firm bonding structure or an integrated structure after cooling and solidification through the same material or similar material as the second connecting portion 321, so that a closed annular connecting structure is constructed to form a closed proximal end structure of the catheter 3, the risk of radial falling out of the catheter 3 embedded into the connecting hole is reduced, and the joint strength of the catheter 3 and the bracket 404 is further enhanced. Specifically, the third connecting portion 322 is integrally formed with the catheter 3 and is formed at the distal end 301 of the catheter 3.

In order to realize the connection between the distal end 301 of the catheter 3 and the proximal end of the stent 404, a (wall-sandwiched) receptacle is provided on the wall of the distal end 301 of the catheter 3, the radially outer side of the receptacle being the second connection portion 321, and the radially inner side of the receptacle being the third connection portion 322. The insertion hole is formed on the end surface of the distal end 301 of the catheter 3, the proximal end of the bracket 404 is inserted into the insertion hole from the insertion hole, the catheter 3 wall is disposed on two radial sides of the first connecting portion 421, the outer wall 321 is formed as the second connecting portion 321, the inner wall 322 is formed as the third connecting portion 322, and the insertion hole is a wall-clamping hole. The second connecting portion 321 has a heat-fusible protrusion (connecting protrusion 323) protruding radially inward into the connecting hole, and an inner end of the heat-fusible protrusion is connected to the third connecting portion 322. The depth of the insertion hole is greater than the axial length of the first connection portion 421 so that the entire number of connection holes enter the insertion hole.

By providing the third connecting portion 322, structural damage of the second connecting portion 321 caused by thermal melting damage can be avoided, the third connecting portion 322 is located at the innermost side, and the proximal end of the bracket 404 is firmly connected by matching with the second connecting portion 321.

In one embodiment of the present disclosure, a method of assembling a stent 404 of a catheter pump with a catheter 3 is provided. The guide tube 3 is internally provided with a driving shaft 300 for driving the impeller 410 to rotate. The bracket 404 is used to support the deployment membrane 401 to form a rotational space that accommodates the impeller 410. The proximal end of the bracket 404 is provided with a connecting secondary tube 43. The connecting secondary pipe 43 is provided with a joint extending through at least part of the wall thickness thereof. The distal end of the catheter 3 is provided with a material portion.

The stent 404 and the catheter 3 in this assembly method may be described with reference to other embodiments of the present disclosure, and the description thereof will not be repeated. It should be noted that, before the assembly method is adopted, the material part may be a tubular or sleeve-shaped structure with a flat surface, and after the material part is hot-melted and solidified to form the above-mentioned jointing material, the surface presents a concave-convex structure, and the jointing part with the concave structure forms an embedded at least axially limited matching structure.

The assembly method comprises the following steps: s10, covering the material part outside the joint part; s20, forming a flowing material flowing into the joint part by the hot-melting material part; s30, solidifying the flowing material to form a connecting structure for connecting the catheter 3 and the support 404.

In step S10, the material portion covers the joint portion and may be covered outside the joint portion by means of bonding contact or peripheral sleeving, so that the flowable material formed in the subsequent hot melting is facilitated to flow into the joint portion, and a connection structure with embedded protrusion structure is formed.

In step S30, the way of solidifying the flowable material may be natural cooling or cryogenic cooling, in which case the material portion is naturally cooled to solidify the flowable material. That is, the connection structure for connecting the catheter 3 and the stent 404 is formed by natural cooling after the material portion is thermally melted. In step S10, the material portion covers the joint portion, and the two positions are not limited to each other at least in the axial direction, so that a connection structure for connecting the two is formed by thermal fusion solidification. The connection structure may be specifically referred to the bonding material described in the other embodiments.

The material portion is integrally provided at the distal end of the catheter 3. The connecting structure is a structure formed by hot melting, solidifying and forming or hot pressing part of the guide pipe 3. That is, the assembly method includes: s10', sleeving the distal end of the catheter 3 outside the connecting secondary tube 43; s20', the distal end of the hot melt catheter 3 flowing part of the catheter 3 material into the junction; s30', curing the material flowing into the junction forms a connecting structure connecting the catheter 3 and the stent 404.

Further, as shown in fig. 29 and 31, the distal end of the catheter 3 is provided with a double-walled insertion hole. The distal end of the catheter 3 has an outer tube wall 321 (second connection 321) radially outside the double-wall socket and an inner tube wall 322 (third connection 322) radially inside the double-wall socket.

Correspondingly, the assembly method comprises the following steps: s10', inserting the connection hypotube 43 into the double-walled socket such that the engagement portion is located within the double-walled socket; s20', hot melting the outer tube wall to enable part of the catheter 3 material to flow into the joint; s30", curing the material flowing into the junction forms a connecting structure connecting the catheter 3 and the stent 404.

As shown in fig. 28 and 29, the connection sub-tube 43 is provided with a proximal bearing chamber on the distal side (front side) of the first connection portion 421. The proximal bearing chamber is located between the first connection 421 and the outlet section 42. A proximal bearing 330 is mounted in the proximal bearing housing. The proximal bearing chamber is of a circular sleeve structure. In one possible embodiment, a proximal bearing chamber is further provided in the connecting sub-tube 43, and a proximal bearing 330 (a first proximal bearing 331 and a second proximal bearing 332) is fixed in the proximal bearing chamber 340 to rotatably support the driving shaft 300.

In the present embodiment, the connection sub tube 43 is further provided with a positioning portion (connection button 431) on the distal side of the first connection portion 421. The positioning part positions and fixes the proximal bearing 330 positioned in the connecting secondary tube 43; the proximal bearing 330 is sleeved outside the drive shaft 300 to rotatably support the drive shaft 300. The outer wall of the proximal bearing 330 is provided with a mating portion that engages the positioning portion. The positioning part and the matching part form a buckling structure.

Specifically, the proximal bearing 330 is directly secured within the connecting sub-tube 43. A connecting buckle 431 (a positioning portion, a male buckle) is provided on the distal side (front side) of the first connecting portion 421 of the connecting sub-tube 43, and a locking groove 336 (a mating portion, a female buckle) is provided on the outer wall of the proximal bearing 330. The proximal bearing 330 is located in the connecting sub-tube 43, and is locked into the locking groove 336 of the outer wall of the proximal bearing 330 by the connecting buckle 431 as a male buckle, thereby axially limiting the proximal bearing 330.

Of course, the proximal bearing 330 is fixed in a desired position at the proximal end of the bracket 404 (connecting the secondary tube) by an interference fit, and the position of the proximal bearing is further limited by the connection buckle 431, so that the axial displacement of the proximal bearing 330 is avoided.

As shown in fig. 27, a collar 357 is also secured within the connecting sub-tube 43 proximal of the proximal bearing 330. The retainer ring 357 contacts the distal end face of the third connecting portion 322. The distance between the collar 357 and the drive shaft 300 is greater than the distance between the proximal bearing 330 and the drive shaft 300.

The connection sub-pipe 43 is provided with a catching hole 432, and the connection button 431 is provided in the catching hole 432 and protrudes inward in the radial direction. The first connection portion 421 is located on the proximal side (rear side) of the connection buckle 431. When the first connecting portion 421 is inserted into the insertion hole at the proximal end of the catheter 3, the insertion depth thereof does not sink into the connecting buckle 431, and the connecting buckle 431 is located outside the insertion hole. When the catheter 3 and the support 404 are inserted relatively, the proximal end face of the connecting secondary tube 43 contacts the bottom of the jack to stop the continuous insertion, and the bottom of the jack can form axial limit for the insertion of the catheter 3 and the support 404. The connecting buckle 431 has a substantially rectangular structure, and the corresponding clamping hole 432 has a rectangular structure. The distal end 301 of the connector link is secured to the connector sub-tube 43 with the other side thereof spaced from the aperture edge of the aperture, thereby allowing some degree of resilient movement of the connector link 431 in the radial direction.

The connection hole 435 and the connection button 431 are formed by cutting on the bracket 404 or cast integrally with the bracket 404, which is not limited in this application. The first connection portion 421 is spaced apart from the connection buckle by a certain distance.

The distal end 301 of the catheter 3 is provided with a rotational support structure comprising at least one proximal bearing 330 for passing the drive shaft 300 therethrough for rotational support of the drive shaft 300. The rotary supporting structure is provided with a limiting piece and a rotary supporting structure which are spaced. At least one of the stop and the rotational support structure is a proximal bearing 330.

In one possible embodiment, as shown in fig. 16, the distal end 301 of the catheter 3 is fixed with a proximal bearing chamber 340 (which may also be referred to as a proximal bearing sleeve), the proximal bearing chamber 340 is a separate component with respect to the catheter 3 and the support 404, the connection sub-sleeve of the support 404 is arranged outside the proximal bearing chamber 340, and a first proximal bearing 331 as a limiting member and a second proximal bearing 332 as a rotation supporting structure are arranged in the proximal bearing chamber 340. The distal end 301 of the catheter 3 has a connection end, the proximal bearing chamber 340 is sleeved on the connection end, the connection sub-tube is fixedly sleeved outside the proximal bearing chamber 340, that is, the proximal end of the proximal bearing chamber 340 is sleeved between the connection sub-tube and the connection end of the catheter 3, the connection sub-tube and the connection sub-tube are relatively fixed, and the proximal bearing chamber 340 provides rigid support for the proximal bearings (the first proximal bearing 331 and the second proximal bearing 332) so as to facilitate the installation of the proximal bearings. The connecting end is formed by reducing the diameter relative to the main body of the catheter 3, a stop step formed by reducing the diameter is arranged between the connecting end and the main body of the catheter 3, and then the stop can be provided for limiting the installation of the connecting secondary pipe 43 and the proximal bearing chamber 340, so that the installation is reminded to be in place, the situation that the connecting end protrudes out of the surface of the catheter 3 after the proximal bearing chamber 340 and the connecting secondary pipe are installed can be avoided, adverse effects on blood flow are formed, and the damage probability of the protrusion to the covering film 401 in a folded state is reduced.

In embodiments such as those shown in fig. 28 and 29, the stop member is a collar 357 fixedly disposed on the distal end of the catheter 3; the rotational support is a proximal bearing 330. The gap width between the collar 357 and the drive shaft 300 is greater than the gap width between the rotational support (proximal bearing 330) and the drive shaft 300. The collar 357 is located proximal to the proximal bearing 330.

The connecting secondary tube 43 of the bracket 404 is connected to the proximal bearing chamber 340 by means of a snap fit, and the proximal bearing chamber 340 is connected to the catheter 3 by means of gluing. The outer wall surface of the proximal bearing chamber 340 has an elongated groove extending in the axial direction that is aligned with the sensor track hole in the catheter 3.

The limiting piece and the rotary supporting structure are arranged at intervals. A stopper 356 is fixed to the outer wall of the drive shaft 300. The stop 356 is located between the stop and the rotational support structure. The stopper 356 moves within an axial range defined by the stopper and the rotational support structure.

In one possible embodiment, the stop 356 is axially sandwiched between the stop and the rotary support structure with an axial spacing equal to the length of the stop 356 in the axial direction. The distal end 301 of the stopper 356 is in contact with the rotational support structure and the proximal end is in contact with the stopper. The stopper 356 is clamped in place by means of a stop and a rotational support structure, so that the axial position of the second shaft 355 to which the stopper 356 is connected is defined.

By providing the stop 356, the proximal end of the second shaft 355 may be prevented from disengaging from the distal end 301 of the first shaft 350. The outer side wall of the stopper 356 is spaced from the inner wall of the proximal bearing housing (the inner wall of the proximal bearing housing 340 or the inner wall of the connecting secondary tube) by a distance, constituting a perfusion fluid flow gap.

The pump body 4 is moved from the radially expanded state to the radially collapsed state, and the distal end of the bracket 404 slides on the second shaft 355 together with the distal end bearing 62 and the distal end bearing chamber 6, so that the length of the bracket 404 is lengthened to reduce the size into the collapsed state.

To avoid slipping of the distal end 3551 of the second shaft 355 off the distal bearing 62 during collapsing, the distal end 3551 of the second shaft 355 extends a distance distal to the distal bearing 62 in the radially expanded state. Preferably, in the radially expanded state, the distal end 3551 of the second shaft 355 is spaced from the occluding component 550 to facilitate outflow of the perfusate.

Specifically, the pump body 4 has a radially collapsed state and a radially expanded state. When the pump body 4 is switched between the radial unfolding state and the radial folding state, the distal end bearing 62 slides relative to the driving shaft and keeps supporting the driving shaft, the axial length of the bracket 404 is prolonged to reduce the size and enter the folding state, and the driving shaft cannot be separated from the distal end bearing 62, so that the repeated execution of folding and unfolding is ensured, the pump body 4 can be smoothly inserted into the body, and the pump body can be smoothly folded and removed from the body after the operation is finished.

In connection with the above description, the drive shaft comprises a first shaft 350 of a smaller stiffness and a second shaft 355 of a larger stiffness, the proximal end of the first shaft 350 being in driving connection with the rotational shaft of the motor 1 and the distal end being connected with the proximal end of the second shaft 355. The impeller 410 is fixedly sleeved on the second shaft 355. The distal end of the bracket 404 slides along the drive shaft along with the distal bearing housing 6 and the distal bearing 62. Specifically, the distal end of the bracket 404 slides along the second shaft 355 along with the distal bearing housing 6 and the distal bearing 62. The rigid second shaft 355 can provide sliding support for the support 404, the distal bearing housing 6, and the distal bearing 62.

In the collapsed state, the distal end face 3552 of the drive shaft is distal to the proximal end face of the distal bearing 62. In the deployed state, the distal end face 3552 of the drive shaft is distal to the distal end face of the distal bearing 62. Specifically, in the collapsed state, the distal end face 3552 of the second shaft 355 is distal to the proximal end face of the distal bearing 62. In the deployed state, the distal end face 3552 of the second shaft is distal to the distal end face of the distal bearing 62.

The length of the distal bearing chamber 6 into which the drive shaft extends gradually decreases during the switching of the deployed state of the pump body 4 to the collapsed state. The length of the distal bearing chamber 6 into which the drive shaft extends gradually increases during the switching of the collapsed state of the pump body 4 to the expanded state.

In the deployed state, the distance between the distal end face 3552 of the drive shaft and the proximal end face of the distal bearing 62 is L1; in the collapsed state, the distance between the distal end face 3552 of the drive shaft and the proximal end face of the distal bearing 62 is L2, L1 being greater than L2. More specifically, in the deployed state, the distance between the distal end face 3552 of the second shaft and the proximal end face of the distal bearing 62 is L1; in the collapsed state, the distance between the distal end face 3552 of the second shaft and the proximal end face of the distal bearing 62 is L2, L1 being greater than L2.

As shown in fig. 30, the (flexible) seal 550 is spaced from the distal end of the second shaft 355, and a gap 560 is formed between the distal end 3551 of the second shaft 355 and the seal 550, which provides an axial play of the second shaft 355 for axial movement of the second shaft 355. The blocking piece 550 may also form an axial stop for the second shaft 355, limiting the position of the far dead center of the axial movement of the blocking piece 550.

Of course, in the presence of the stop 356 in the above embodiment, the distal end of the second shaft 355 is not in contact with the closure member 550 when the stop 356 is in contact with the second proximal bearing 332, and is spaced apart to avoid axial movement of the second shaft 355 from damaging the closure member 550.

In the radially collapsed state, the distal end face 3552 of the second shaft 355 is at least distal to the proximal end face of the distal bearing 62, to ensure that the second shaft 355 is not ever dislodged from the distal bearing 62. Alternatively, in the radially expanded state, the distance between the distal end face 3552 of the second shaft 355 and the proximal end face 621 of the distal bearing 62 is greater than the distance between the distal end face 3552 of the second shaft 355 and the proximal end face 621 of the distal bearing 62 in the radially collapsed state.

It is to be understood that the above description is intended to be illustrative, and not restrictive. Many embodiments and many applications other than the examples provided will be apparent to those of skill in the art upon reading the above description. The scope of the present teachings should, therefore, be determined not with reference to the above description, but instead should be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. The disclosures of all articles and references, including patent applications and publications, are incorporated herein by reference for the purpose of completeness. The omission of any aspect of the subject matter disclosed herein in the preceding claims is not intended to forego such subject matter, nor should the inventors regard such subject matter as not be considered to be part of the disclosed subject matter.

Claims

1. A catheter pump, comprising:

a motor;

a catheter connected proximally to the motor;

a drive shaft driven by the motor;

the proximal end of the support is provided with a connecting secondary pipe, the connecting secondary pipe is provided with a joint part penetrating through at least part of the wall thickness of the connecting secondary pipe, and the distal end of the catheter is provided with a joint material which is accommodated in the joint part and is formed by hot melting and solidification.

2. The catheter pump of claim 1, wherein the connection sub-tube is sleeved outside the distal end of the catheter, an intermediate connecting sleeve is sleeved outside the connection sub-tube, and the joint material is formed by heat-melting and then curing the intermediate connecting sleeve.

3. The catheter pump as claimed in claim 2, wherein part of the intermediate connecting sleeve is adhered and sleeved on the outer wall of the catheter after being hot melted, or part of the intermediate connecting sleeve is adhered on the outer wall of the catheter, or the outer wall of the catheter is provided with a caulking groove for accommodating an embedded protrusion formed by curing part of the intermediate connecting sleeve after being hot melted.

4. The catheter pump of claim 1, wherein the bonding material is a heat-melt cured structure of a portion of the catheter.

5. The catheter pump of claim 1, wherein the joint comprises a limiting depression open on the wall of the connecting secondary tube, and the joint material comprises a hot melt cured connecting protrusion; the connecting protrusion is clamped into the limiting recess to fix the catheter and the bracket at least axially.

6. The catheter pump of claim 5, wherein the distal end of the connection hypotube includes a first connection having the limiting recess; the distal end of the catheter includes a second connection portion having the connection protrusion; the second connecting part is sleeved outside the first connecting part, and the connecting protrusion is clamped into the limiting recess; the limiting recess penetrates through the wall of the connecting secondary pipe in the radial direction; the connecting protrusion is formed by the second connecting part through heat melting, and then solidifying part of the conduit material flowing into the limit recess.

7. The catheter pump of claim 6, wherein the limiting recess comprises a plurality of connection holes provided on the connection sub-tube radially penetrating the connection sub-tube wall.

8. The catheter pump of claim 7, wherein the connection hole is a long hole extending in a circumferential direction; the plurality of connecting holes are arranged in parallel along the axial direction of the connecting secondary pipe; the adjacent two connecting holes are at least partially staggered or overlapped in the axial direction.

9. The catheter pump of claim 6, wherein a third connection is further provided radially inward of the first connection; the connecting protrusion penetrates through the limiting recess and is adhered to the third connecting part or is of an integrated structure; the second connecting part, the third connecting part and the catheter are of an integrated structure.

10. The catheter pump of claim 9, wherein a wall-gripping receptacle is provided in a wall of the catheter distal end; the radial outer pipe wall of the double-wall jack is the second connecting part, and the radial inner pipe wall of the double-wall jack is the third connecting part; the double-walled insertion hole forms an insertion opening into which the first connection portion is inserted, on an end face of the distal end of the catheter.

11. The catheter pump of claim 10, wherein the connection hypotube is further provided with a locating portion distal to the first connection portion; the positioning part is used for positioning a proximal bearing in the connecting secondary pipe; the proximal end bearing is sleeved outside the driving shaft to rotatably support the driving shaft; the outer wall of the proximal bearing is provided with a matching part which is jointed with the positioning part; the positioning part and the matching part form a buckling structure.

12. The catheter pump of claim 11, wherein the locating portion comprises a plurality of radially inwardly projecting male tabs arranged circumferentially; the matching part comprises a clamping groove clamped by the male buckle on the outer wall of the proximal bearing.

13. The catheter pump of claim 11, wherein the interior of the connection hypotube is further secured with a retainer ring proximal to the proximal bearing; the retainer ring is in contact limit with the distal end face of the third connecting part; the spacer ring is spaced from the drive shaft a distance greater than the distance between the proximal bearing and the drive shaft.