CN219185598U

CN219185598U - Catheter pump and intervention assembly thereof

Info

Publication number: CN219185598U
Application number: CN202222813405.XU
Authority: CN
Inventors: 屠攀; 张家良
Original assignee: Magassist Inc
Current assignee: Xinqing Medical Suzhou Co ltd
Priority date: 2022-10-25
Filing date: 2022-10-25
Publication date: 2023-06-16
Anticipated expiration: 2032-10-25

Abstract

Disclosed are an intervention assembly of a catheter pump and the catheter pump, the catheter pump comprising: the catheter, rotationally wear drive shaft, the pump head of establishing in the catheter, intervene the subassembly and include first sheath, second sheath, third sheath. A portion of the pump head is folded into the first sheath first channel via the distal end of the first sheath; at least part of the pump head is transferred from the first channel into the second channel of the second sheath in a collapsed state by pushing the catheter forward; by pushing the catheter forward, at least part of the pump head is transferred from the second channel into the third channel of the third sheath in a collapsed state. The pump head is folded step by using the first sheath and the second sheath, so that the folding difficulty is low, the pump head is not easy to damage in the folding process, the pushing process is smoother, the length of the first sheath is shorter, the strokes of folding the pump head into the first sheath and transferring the pump head from the first sheath to the second sheath are correspondingly shortened, and the damage of the pump head is reduced; when the pump head is transferred from the second sheath to the third sheath, the pump head is not further compressed and folded, so that the pain of a patient and the complication probability of a puncture opening are reduced.

Description

Catheter pump and intervention assembly thereof

Technical Field

The utility model relates to an intervention component of a catheter pump and the catheter pump, and belongs to the technical field of medical appliances.

Background

Heart disease is a health problem with high mortality rates and physicians increasingly use mechanical circulatory support systems to treat heart failure. The treatment of acute heart failure requires a device that can quickly provide support to the patient and physicians desire to quickly and minimally invasively deploy a treatment regimen.

Mechanical Circulatory Support (MCS) systems and Ventricular Assist Devices (VADs) are increasingly accepted in the treatment of acute heart failure. For example, patients after cardiogenic shock are stabilized in the treatment of acute Myocardial Infarction (MI) or compensatory heart failure, or support is provided to the patient during high-risk Percutaneous Coronary Intervention (PCI). One example of an MCS system is a rotary catheter pump placed percutaneously via a catheter.

In conventional approaches, a catheter pump is inserted into the body and connected to the cardiovascular system (e.g., connecting the left ventricle and the ascending aorta) to assist the pumping function of the heart.

At present, catheter pumps in the field are divided into two types, namely a motor built-in pump head is not foldable and a motor external pump head is foldable. For the purposes of reducing patient pain and reducing complications of the puncture, catheter pumps are expected to be capable of smaller size interventions in the human body. As the catheter pump with the foldable pump head can achieve smaller wound when in intervention, the catheter pump has become a future development trend.

The distal pump head of the collapsible catheter pump is in a self-expanding, deployed configuration, requiring the pump head to be collapsed in vitro in order to deliver it into a human blood vessel with a small access size. The known embodiment as publication No. US9974893B2 provides the following solutions:

comprises a first sheath for receiving an expandable pump, the proximal end of the pump being connected to a catheter;

comprises a second sheath which is sleeved on the catheter and pulls the catheter, the expandable pump is pulled into the second sheath from the distal end of the second sheath, and the expandable pump is in a folded state in the second sheath;

the second sheath distal end is coupled to the first sheath proximal end, the expandable pump is advanced from the second sheath into the first sheath through the catheter, and the expandable pump remains in a compressed state, and the expandable pump expands as it is pushed out of the first sheath distal end.

Briefly, this known embodiment provides a solution comprising two sheaths, a first sheath as an interventional sheath and a second sheath as a folded sheath. By pre-folding the collapsible pump head into a folded sheath, the folded sheath is then directly coupled to the interventional sheath. The pump head is pushed from the folding sheath into the interventional sheath and finally enters the blood vessel for deployment.

The pump head folded by adopting the scheme has the following defects:

1. the pump head is expected to be folded once in vitro by adopting the folding sheath to realize the required folding size, so that the folding degree of the pump head is higher and the folding difficulty is higher. The performance is that the pump head is relatively blocked in the sheath, and the friction force is large.

2. In the interventional sheath, the pump head is further compressed and collapsed. However, in the interventional sheath, the pump head is in a forward pushing stage, and further folding of the pump head causes an increase in frictional resistance between the pump head and the interventional sheath, resulting in difficulty in pushing the pump head. In addition, the pump head which is further folded exerts strong reverse acting force on the intervention sheath, so that the intervention sheath can be expanded radially, further the puncture opening is expanded or even torn, and the pain of a patient and the complication probability of the puncture opening are increased.

3. The distal end of the pump head is typically provided with a soft atraumatic Member, including a Pigtail (Pigtail Tip) as provided in US9833550B2 or a Tip Member (Tip Member) as provided in US9421311B 2. In order to allow the soft atraumatic member to smoothly penetrate the hemostatic valve in the proximal end of the access sheath, the atraumatic member is received within the folded sheath when the pump head is folded over the body to penetrate the hemostatic valve by means of the folded sheath so that the atraumatic member smoothly enters the access sheath. This results in the length of the folded sheath being configured so that it must be possible to receive both the pump head and the atraumatic member therein, i.e. the folded sheath is longer. Therefore, the pump head has longer moving travel in the folded sheath in the folded state in the process of folding the pump head into the folded sheath and transferring the pump head into the interventional sheath, and the pump head is extremely easy to damage.

Disclosure of Invention

The utility model aims to provide an intervention component of a catheter pump and the catheter pump, which at least solve one of the technical problems.

In order to achieve the above purpose, the present utility model provides the following technical solutions:

the present utility model provides an interventional assembly for a catheter pump, the catheter pump comprising:

a conduit;

a drive shaft rotatably penetrating the guide tube;

a collapsible pump head that can be delivered to a desired location of the heart through the catheter to pump blood, comprising: a pump housing connected to the distal end of the catheter, an impeller received in the pump housing; the impeller is connected to a distal end of the drive shaft, the proximal end of the drive shaft being connectable to a motor to transmit rotation of the motor to the impeller;

the interventional assembly comprises:

a first sheath slidably sleeved outside the catheter and provided with a first channel; by pulling the catheter back and/or pushing the first sheath forward, a portion of the pump head collapses into the first channel via the distal end of the first sheath;

a second sheath having a proximal end operably interfacing with a distal end of the first sheath, with a second passageway; at least part of the pump head is transferred from the first channel into the second channel in a collapsed state by pushing the catheter forward;

a third sheath configured to be partially inserted into the vasculature of a subject through the puncture and having a proximal end operably interfacing with a distal end of the second sheath, with a third passageway; by pushing the catheter forward, at least part of the pump head is transferred from the second channel into the third channel in a collapsed state and the pump head is delivered to the vascular system in a collapsed state.

Preferably, the inner diameter of the second channel is smaller than the inner diameter of the first channel.

Preferably, the inner diameter of the third channel is substantially equal to the inner diameter of the second channel.

Preferably, the distal end of the stent is connected with a protective tip; the length of the first channel is greater than the length of the stent in the collapsed state but less than the sum of the length of the stent in the collapsed state and the guard tip.

Preferably, the sum of the lengths of the first and second channels is greater than the sum of the lengths of the stent and the guard tip in the collapsed state.

Preferably, a hemostatic valve is arranged at the proximal end in the third channel;

the distal end of the guard tip is positioned within the second channel while the first sheath distal end is docked with the second sheath proximal end and the stent and impeller of the pump head are still positioned within the first channel;

the distal end of the second sheath is inserted into the third passageway and through the hemostatic valve when the distal end of the second sheath is docked with the proximal end of the third sheath.

Preferably, the length of the second channel is greater than the sum of the length of the stent and the guard tip in the collapsed state.

the distal end of the guard tip is positioned within the second channel when the holder and impeller of the pump head are transferred from the first channel into the second channel;

The present utility model also provides a catheter pump comprising: a catheter pump, and an intervention assembly adapted to intervene the catheter pump in a vasculature of a subject;

the catheter pump includes:

a conduit;

a drive shaft rotatably penetrating the guide tube;

the interventional assembly comprises:

The utility model has the beneficial effects that:

when the foldable pump head is folded in vitro, the pump head is pre-folded by using the first sheath, then the pump head is further folded to a folded state by using the second sheath, a step-by-step folding mode is used, the folding difficulty is small, the pump head is not easy to damage in the folding process, and the pushing process is smoother, meanwhile, the length of the first sheath is shorter, the support and the impeller of the pump head are folded into the first sheath, and the strokes of folding the pump head into the first sheath and transferring the pump head from the first sheath to the second sheath are correspondingly shortened, so that the damage of the pump head is further reduced;

when the pump head is transferred from the second sheath to the third sheath, the third sheath is not compressed and folded any more, so that the third sheath cannot expand radially due to the fact that the pump head enters the third sheath, the puncture opening is expanded or even torn, and pain of a patient and the complication probability of the puncture opening are reduced.

In addition, by means of the mode that the pump head is pre-folded in vitro by the double sheaths (the first sheath and the second sheath), the pump head, particularly the part with higher folding difficulty of the pump head, namely the support and the impeller are folded step by step and transferred, and the distance or the travel of the part with higher folding difficulty in the folding state is shorter by the size arrangement between the double sheaths and the support and the protective head, so that damage to the pump head is reduced.

Drawings

Fig. 1 is a schematic perspective view of a catheter pump provided by the present utility model.

Fig. 2 is a schematic perspective view of a part of the structure of the catheter pump provided by the utility model.

Fig. 3 is a schematic perspective view of a catheter pump, a primary sheath and a secondary sheath provided by the present utility model.

Fig. 4 is another perspective view of a catheter pump, primary sheath and secondary sheath provided by the present utility model.

Fig. 5 is a schematic cross-sectional view of a catheter pump, primary sheath and secondary sheath provided by the present utility model.

Fig. 6 is a schematic perspective view of a primary sheath and a secondary sheath provided by the present utility model.

Fig. 7 is a schematic perspective view of a catheter pump and secondary sheath provided by the present utility model.

Fig. 8 is a schematic cross-sectional view of a stent and impeller of a primary sheath collapsible pump head provided by the present utility model.

Fig. 9 is a schematic cross-sectional view of a first sheath and a second sheath interface provided by the present utility model.

Fig. 10 is a schematic cross-sectional view of a second sheath and third sheath interface provided by the present utility model.

Fig. 11 is a schematic cross-sectional view of a second sheath and a third sheath interfacing with the removal of the first sheath provided by the present utility model.

Detailed Description

The present utility model will be described in detail below with reference to specific embodiments shown in the drawings. These embodiments are not intended to limit the utility model and structural, methodological, or functional modifications of these embodiments that may be made by one of ordinary skill in the art are included within the scope of the utility model.

The terms "proximal", "posterior" and "distal", "anterior" as used herein are relative to a clinician manipulating the catheter pump of the present embodiment. 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 motor is at the proximal and rear ends and the guard tip is at the distal and front ends; for another example, the proximal end of a member/assembly represents an end relatively close to the motor and the distal end represents an end relatively close to the guard tip.

The catheter pump of the present utility model defines an "axial" or "axial extension" with the extension of the drive shaft. As used herein, the term "inner", "outer" is with respect to an axially extending centerline, and is "inner" with respect to a direction closer to the centerline and "outer" with respect to a direction farther from the centerline.

It will 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. For example, the above definition of each direction is only for the convenience of illustrating the technical solution of the present utility model, and is not limited to the direction of the catheter pump of the present utility model in other scenarios including, but not limited to, product testing, transportation and manufacturing, etc., which may cause the inversion or position change thereof. 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, the terms "connected," "connected," and the like should be construed broadly unless otherwise specifically indicated and defined. For example, the device can be fixedly 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.

In addition, the technical features of the different embodiments of the present utility model described below may be combined with each other as long as they do not collide with each other.

Referring to fig. 1 and 2, a catheter pump 100 according to an embodiment of the present utility model may be at least partially inserted into a subject to assist in the pumping function of the heart and reduce the heart burden. Catheter pump 100 may act as a left ventricular assist, pumping blood in the left ventricle into the ascending aorta. It can also be used as a right ventricular assist to pump venous blood to the right ventricle.

The scenario will be described below primarily with catheter pump 100 as left ventricular assist. It will be appreciated from the foregoing that the scope of embodiments of the utility model is not limited thereby.

Catheter pump 100 includes a motor 1, a catheter 2, a drive shaft (not shown) rotatably disposed through catheter 2, a collapsible pump head 3 that can be delivered through catheter 2 to a desired location of the subject's heart, such as the left ventricle pumps blood, and a coupler 4 connected to the proximal end of catheter 2 for releasable engagement with motor 1.

The collapsible pump head 3 includes a pump housing 31 connected to the distal end of the catheter 2 and having an inlet end 311 for blood to enter and an outlet end 312 for blood to exit, and an impeller (not shown) housed within the pump housing 31. The impeller comprises a hub and blades supported on the outer wall of the hub. The drive shaft is connected at a proximal end to the motor 1 and at a distal end to the hub of the impeller to transfer the rotation of the motor 1 to the impeller. The drive shaft comprises a flexible shaft which is flexible and a hard shaft which is connected to the distal end of the flexible shaft, the flexible shaft is penetrated in the catheter 2, and the hard shaft is penetrated in the hub.

In this embodiment, the pump housing 31 includes a support 313 made of nickel, titanium alloy in a metallic lattice and connected to the distal end of the catheter 2, and an elastic coating 314 covering the support 313. Wherein the front end of the covering film 314 is connected to the support 313, and the rear end is located at the rear side of the support 313. That is, the mesh of the portion of the front end of the support 313 not covered with the covering film 314 forms the inlet end 311. The rear end of the covering film 314 is covered outside the distal end of the catheter 2, and the outlet end 312 is an opening formed at the rear end of the covering film 314.

Specifically, the support 313 includes a cylindrical structure 3131 and tapered structures 3132 at both ends of the cylindrical structure. When the covering film 314 is covered on the support 313, the front end of the covering film 314 is connected to the cylindrical structure 3131 located in the middle, the tapered structure 3132 located at the front end is exposed, and the tapered structure located at the rear end is located in the covering film 314.

As described above, the impeller is housed in the pump casing 31. Specifically, the impeller is housed in a bracket 313. The proximal and distal ends of the support 313 are connected to a proximal bearing housing (not shown) and a distal bearing housing 32, respectively, and proximal and distal bearings (not shown) are provided in the proximal and distal bearing housings 32, respectively. The proximal end and the distal end of the hard shaft are respectively penetrated in the proximal end bearing and the distal end bearing. Thus, the two ends of the hard shaft are supported by the two bearings, and the high rigidity of the hard shaft allows the impeller to be preferably held in the pump housing 31.

The coupler 4 and the motor 1 may be detachably connected by means of a lock nut or a snap-on connection as provided in US9421311B 2. The motor 1 drives the driving part, a rotor is arranged in the coupler 4, the rotor comprises a rotor shaft and a driven part arranged on the rotor shaft, the proximal end of the driving shaft is connected to the rotor shaft, the driven part is coupled with the driving part to transmit the rotation power of the motor 1 when the motor is started to the driving shaft, and then the impeller is driven to rotate for pumping blood. The driven member and the driving member may be magnetically coupled, such as provided by CN103120810B or CN101820933B, i.e., the driven member and the driving member are both magnets. Alternatively, the follower and the driving member may employ an eddy current linkage (Eddy Current Coupling) as provided by CN216061675U or CN114452527a, i.e. one of the follower and the driving member is a magnet and the other is a conductor.

The distal end of the support 313 is connected to a protective tip 5, the protective tip 5 being configured to be flexible so as not to injure the tissue of the subject, the protective tip 5 being made of any macroscopic material exhibiting flexibility. The flexible end part is supported on the inner wall of the ventricle in a noninvasive or atraumatic way, separates the suction inlet of the pump head 3 from the inner wall of the ventricle, avoids the suction inlet of the pump head 3 from being attached to the inner wall of the ventricle due to the reaction force of fluid (blood) in the working process of the pump head 3, and ensures the effective area of pumping.

The pump head 3 and the front end portion of the catheter 2 are fed into and held in the subject, and it is desirable that the size of the pump head 3 and the catheter 2 be as small as possible. The smaller size pump head 3 and catheter 2 can enter the subject's body through the smaller puncture size, reducing the pain of the subject caused by the interventional procedure, and reducing complications caused by oversized puncture.

Therefore, in order to reduce the size of the puncture and to ensure a large flow rate of the pump head 3, the pump head 3 is a collapsible pump having a collapsed state and an expanded state. In particular, in the corresponding insertion configuration of the pump head 3, the pump housing 31 and the impeller are in a collapsed state, the pump head 3 being inserted into and/or delivered in the subject's vasculature at a first smaller outer diameter dimension. In the corresponding operating configuration of the pump head 3, the pump housing 31 and the impeller are in a deployed state so that the pump head 3 pumps blood in the left ventricle of the heart at a second outer diameter dimension which is larger than the first outer diameter dimension.

By providing the collapsible pump head 3, the pump head 3 has a smaller collapsed size and a larger expanded size, so as to reduce pain of a subject and ease intervention in the intervention/transportation process, and provide a large flow.

The support 313 of the pump housing 31 is preferably folded in a multi-mesh, in particular diamond-mesh, design, and is unfolded by means of the memory properties of the nitinol. The cover 314 is made of flexible material and can be folded and unfolded.

The blades of the impeller are made of flexible materials and can be bent relative to the hub, and the impeller has a folded configuration and an unfolded configuration. The blade tip of the blade in the collapsed configuration is proximate to the hub and the blade tip of the blade in the expanded configuration is distal to the hub. The energy storage of the blade is released after the external constraint is removed, so that the blade is unfolded, and the radially outer side of the blade is unfolded to be in a state of maximum radial dimension.

The pump head 3 is folded by means of external constraint, and after the constraint is removed, the pump head 3 is self-unfolded. In the present embodiment, the "collapsed state" refers to a state in which the pump head 3 is radially restrained, that is, a state in which the pump head 3 is radially compressed and collapsed to a minimum radial dimension by external pressure. The "deployed state" refers to a state in which the pump head 3 is not radially constrained, that is, a state in which the bracket 313 and the impeller are deployed radially outward to the maximum radial dimension.

Referring to fig. 3-11, catheter pump 100 is inserted into a subject, and may be implemented by an insertion assembly. In this embodiment, the interventional assembly comprises a first sheath 6, a second sheath 7 and a third sheath 8.

In view of the above, it is desirable that the catheter pump 100 be capable of being inserted into a subject in a smaller size, that is, that the catheter pump 100 be inserted into the subject in a collapsed state, from the viewpoints of alleviating pain of a patient and reducing complications of a puncture. In this embodiment, the catheter pump 100 is folded in vitro by the cooperation of the first sheath 6 and the second sheath 7.

Specifically, referring to fig. 7 and 8, a primary sheath 6 is slidably disposed over the catheter 2 and has a primary passageway 61. By pulling the catheter 2 back and/or pushing the primary sheath 6 forward, a portion of the pump head 3 is collapsed into the primary channel 61 via the distal end of the primary sheath 6. In this embodiment, at least the support 313 and impeller of the pump head 3 are folded into the primary channel 61 via the distal end of the primary sheath 6. Wherein the operation of pulling the catheter 2 backward and/or pushing the primary sheath 6 forward includes three cases, one is pulling the catheter 2 backward, one is pushing the primary sheath 6 forward, and the third is pushing the primary sheath 6 forward while pulling the catheter 2 backward.

Then, referring to fig. 9, the proximal end of the second sheath 7 is operably docked with the distal end of the first sheath 6, which has a second channel 71; by pushing the catheter 2 forward, at least part of the pump head 3 is transferred from the first channel 61 into the second channel 71 in a collapsed state, so as to switch the pump head 3 from the deployed state to the collapsed state.

In this embodiment, the inner diameter of the second channel 71 is smaller than the inner diameter of the first channel 61, and the inner diameter of the second channel 71 is approximately equal to the outer diameter of the pump head 3 in the collapsed state. The pump head 3 is folded step by step in vitro by the first sheath 6 and the second sheath 7. Specifically, after the support 313 and impeller of the pump head 3 enter the first channel 61, the first sheath 6 performs primary folding of the pump head 3. After the pump head 3 enters the second channel 71 from the first channel 61, the second sheath 7 performs a secondary folding of the pump head 3. Compared with the one-time folding in the prior art, each folding in the step-by-step folding has lower folding degree of the pump head 3, lower folding difficulty, less damage to the pump head 3 in the folding process, smoother intervention pushing process and lower friction force.

It should be noted that, the strength of the support 313 is relatively high, and the difficulty of folding the support 313 is greater than that of folding the covering film 314. Therefore, the first sheath 6 is finally folded to form the support 313 with a relatively high folding difficulty, and the covering film 314 is folded by the first sheath 6 when the catheter 2 is pushed forward to transfer the pump head 3 to the second sheath 7.

In order to shorten the stroke of the pump head 3 in the primary sheath 6, the length of the primary sheath 6 is short. In one embodiment, the length of the first channel 61 is greater than the length of the support 313 in the collapsed state but less than the sum of the length of the support 313 and the guard tip 5 in the collapsed state. When the primary sheath 6 is folded up the pump head 3, only the support 313 and the impeller are folded up into the primary channel 61, the covering film 314 is not completely folded up into the primary channel 61, the covering film 314 is at least partially exposed, and the protection tip 5 is exposed outside the primary channel 61. There is no need to protect the tip 5 from entering the primary channel 61, so that the stroke of collapsing the pump head 3 into the primary sheath 6 is short, and the stroke of transferring the pump head 3 from the primary sheath 6 to the secondary sheath 7 is short, thereby reducing the damage to the pump head 3.

Alternatively, in another embodiment, the length of the first channel 61 is greater than the distance between the inlet end 311 and the outlet end 312 of the pump housing 31, but less than the distance between the outlet end 312 and the distal end of the guard tip 5. When the primary sheath 6 collapses the pump head 3, at least a portion of the structure of the pump head 3 (including the support 313, impeller, and a portion of the at least partial membrane 314) between the inlet end 311 and the outlet end 312 is collapsed into the primary channel 61, but the protective tip 5 remains exposed outside the primary channel 61. This embodiment increases the travel of the pump head 3 from the primary sheath 6 to the secondary sheath 7 compared to the previous embodiment, but the travel of the pump head 3 in the collapsed state is still partially shortened compared to conventional pre-collapse schemes that require stowing into the primary sheath 6 along with the protective tip 5.

Furthermore, this embodiment is such that, after pre-collapsing, at least the portion of the pump head 3 between the inlet end 311 and the outlet end 312 is collapsed into the first channel 61. Thus, after the priming and the venting of the catheter pump 100 are completed, the inlet end 311 to the outlet end 312 are prevented from being exposed to air, and the air is prevented from entering the pump head 3 again through the inlet end 311 and/or the outlet end 312, so that the pump head 3 is prevented from being subsequently inflated to be involved in a human body. This is critical for patient safety.

When the proximal end of the second sheath 7 and the distal end of the first sheath 6 are docked, the guard tip 5 is located within the second sheath 7. In this embodiment, the guard tip 5 extends along the axis of the pump head 3, i.e. the guard tip 5 is straight, so that it can smoothly enter the second sheath 7 from the distal end.

When the length of the second channel 71 is sufficiently long, the entire pump head 3 can be folded into the second channel 71; when the length of the second channel 71 is short, only the support 313 and the impeller can be folded into the second channel 71, and the cover 314 is located outside the second channel 71. This arrangement reduces the travel of the pump head 3 from the primary sheath 6 to the secondary sheath 7 to reduce damage to the pump head 3.

When the second sheath 7 and the first sheath 6 are docked, the catheter 2 needs to be pushed forward to transfer at least part of the pump head 3 transfer from the first sheath 6 to the second sheath 7. In order to avoid that the first sheath 6 is separated from the second sheath 7 when the pump head 3 is pushed forward, the second sheath 7 and the first sheath 6 need to be kept axially relatively fixed, so that the pump head 3 can be smoothly transferred into the second sheath 7 in a folded state.

Referring to fig. 6, in the present embodiment, the first sheath 6 and the second sheath 7 are detachably connected. Specifically, the distal end of the primary sheath 6 is provided with a primary member 62, and the proximal end of the secondary sheath 7 is provided with a secondary member 72 that mates with the primary member 62, the primary member 62 and secondary member 72 being removably lockable. The second sheath 7 and the first sheath 6 are subjected to relative rotational movements to effect locking or unlocking of the first member 62 and the second member 72. The specific structure of the first member 62 and the second member 72 and the manner of fitting therebetween are not particularly limited, and may be set according to actual needs.

The third sheath 8 may be partially inserted into the vasculature of the subject through the puncture. The front end of the third sheath 8 enters the vascular system through the puncture and the rear end remains outside the human body for forming or establishing a recitation of the device into the vascular system.

Referring to fig. 10 and 11, the proximal end of the third sheath 8 is operably docked with the distal end of the second sheath 7, which has a third passageway 81. By pushing the catheter 2 forward, at least part of the pump head 3 is transferred from the second channel 71 into the third channel 81 in a collapsed state, so that the pump head 3 is delivered in a collapsed state through the third sheath 8 to the vascular system, enabling the pump head 3 to enter the subject with a smaller intervention size.

Wherein the inner diameter of the third channel 81 is substantially equal to the inner diameter of the second channel 71. When the pump head 3 enters the third channel 81, the pump head 3 is not compressed and folded any more, the friction resistance of the pump head 3 entering the third channel 81 is small, and the pushing is smooth. And the risk that the puncture opening is expanded or even torn due to radial expansion of the pump head 3 entering the puncture opening is avoided, and the pain of a patient and the probability of complications of the puncture opening are reduced.

A hemostatic valve 82 is provided proximally within the third passage 81. The hemostatic valve 82 prevents blood in the blood vessel from exiting the body through the hollow structure of the third sheath 8 when the third sheath 8 is inserted into the puncture. The hemostatic valve 82 may be a balloon, rubber or silicone flexible material.

Because the guard tip 5 is relatively soft, it cannot pass through the hemostatic valve 82. The distal end of the guard tip 5 is located within the second channel 71 as the pump head 3 is transferred from the second sheath 7 to the third sheath 8. Specifically, in one embodiment, the sum of the lengths of the first channel 61 and the second channel 71 is greater than the sum of the lengths of the support 313 and the guard tip 5 in the collapsed state. With the distal end of the primary sheath 6 abutting the proximal end of the secondary sheath 7 and the support 313 and impeller of the pump head 3 still located within the primary channel 61, the distal end of the guard tip 5 is located within the secondary channel 71. Under the premise of ensuring that the primary sheath 6 is short enough, when the distal end of the secondary sheath 7 is butted with the proximal end of the tertiary sheath 8, the distal end of the secondary sheath 7 is inserted into the tertiary channel 81 and passes through the hemostatic valve 82, so as to facilitate the forward pushing of the protective tip 5 and avoid the damage to the protective tip 5.

In another embodiment, the length of the second channel 71 is greater than the sum of the length of the support 313 and the guard tip 5 in the collapsed state. The distal end of the guard tip 5 is located in the second channel 71 when the support 313 and impeller of the pump head 3 are transferred from the first channel 61 into the second channel 71. With the distal end of the second sheath 7 docked with the proximal end of the third sheath 8, the distal end of the second sheath 7 is inserted into the third channel 81 and through the hemostatic valve 82, likewise protecting the tip 5 from damage.

Likewise, the distal end of the secondary sheath 7 and the proximal end of the tertiary sheath 8 may also be provided with cooperating locking assemblies (not shown) by which the relative locking or removal between the secondary sheath 7 and the tertiary sheath 8 is achieved. When the catheter 2 is pushed forward, the second sheath 7 and the third sheath 8 are locked by the locking assembly, both remaining axially fixed relative to each other.

Referring to fig. 7 to 11, the present utility model further provides a method for folding the pump head 3 of the catheter pump 100 as described above, comprising:

pulling the catheter 2 back and/or pushing the primary sheath 6 forward, at least the support 313 and impeller of the pump head 3 collapsing into the primary channel 61 via the distal end of the primary sheath 6;

abutting the distal end of the first sheath 6 with the proximal end of the second sheath 7, pushing the catheter 2 forward, at least part of the pump head 3 being transferred from the first channel 61 into the second channel 71 in a collapsed state;

the distal end of the second sheath 7 is brought into abutment with the proximal end of the third sheath 8, the catheter 2 is pushed forward and at least part of the pump head 3 is transferred from the second channel 71 into the third channel 81 in a collapsed state.

Specifically, referring to fig. 7 and 8, the primary sheath 6 is slidably disposed over the catheter 2, and the catheter 2 is pulled back, or the primary sheath 6 is pushed forward, or the catheter 2 is pulled back while the primary sheath 6 is pushed forward. Because the primary sheath 6 is relatively short, only the support 313 and impeller of the pump head 3 collapse into the primary channel 61. After the support 313 and impeller of the pump head 3 are folded into the first channel 61 via the distal end of the first sheath 6, at least the support 313 and impeller are fully folded into the first channel 61, protecting the front end of the tip 5 from being outside the front end of the first channel 61, thereby reducing the folding stroke of the pump head 3 within the first sheath 6.

In one embodiment, the length of the primary sheath 6 only supports collapsing the support 313 and impeller into the primary channel 61, while the rear end of the cover 314 is located outside the rear end of the primary channel 61, which is advantageous in reducing the travel of the support 313 and impeller under collapsing.

Of course, in another embodiment, to avoid re-entering the pump housing 31 through the inlet end 311 and/or the outlet end 312 of the pump head 3 after exhausting, the length of the first sheath 6 is slightly longer than that of the previous embodiment, so as to support the pump head 3 to be folded into the first channel 61 at a portion between the inlet end 311 and the outlet end 312.

In both embodiments, the protection tip 5 is ensured to be exposed outside the first channel 61 after the first sheath 6 has been pre-folded over the pump head 3. This is to reduce the moving distance of the support 313 and the impeller in the folded state, and to reduce damage to the pump head 3.

Referring to fig. 9, the distal end of the primary sheath 6 is docked with the proximal end of the secondary sheath 7, the guard tip 5 is positioned within the secondary channel 71, and the catheter 2 is advanced such that the support 313, impeller and guard tip 5 of the pump head 3 are positioned within the secondary channel 71, and the cover 314 may be positioned within the secondary channel 71 or within the primary channel 71.

The first sheath 6 and the second sheath 7 remain axially stationary during transfer of the pump head 3 from the first channel 61 into the second channel 71. Which is achieved by the locking of the first part 62 and the second part 72.

Referring to fig. 10 and 11, the third sheath 8 is partially inserted into the vasculature of the subject through the puncture.

Likewise, the second sheath 7 and the third sheath 8 remain axially stationary during transfer of the pump head 3 from the second channel 71 into the third channel 81, which is accomplished by the locking of the locking assembly.

To facilitate removal of the primary sheath 6, the primary sheath 6 has a lateral opening at the proximal end along which the primary sheath 6 can be peeled apart, saving labor and facilitating operation. The lateral openings may be provided in two, two being oppositely arranged on both sides of the proximal end of the third sheath 8. The primary sheath 6 has two handles 63 disposed opposite each other at the proximal end, which facilitates the operator's tearing of the primary sheath 6 by holding the two handles 63, improving its operability. The structure of the primary sheath 6 is not particularly limited herein, but may be other structures that are convenient to remove, for example, the primary sheath 6 may be connected with a pre-pressing slit on two sides of the symmetrical position.

After at least a portion of the pump head 3 is transferred into the third channel 81 in the collapsed state, the method further comprises: the catheter 2 is pushed forward continuously, so that the pump head 3 is moved out of the distal end of the third sheath 8 in a folded state, after the constraint is removed, the pump shell supports the elastic covering film 314 to be unfolded under the action of the self memory property, the impeller is self-unfolded under the action of released energy storage, the pump head 3 is conveyed to the vascular system in an unfolded state and is inserted into the left ventricle, and the motor 1 and the catheter 2 are connected in a matched mode, so that the blood pumping working state of the catheter pump 100 is realized.

In a comprehensive way, when the foldable pump head is folded in vitro, the pump head is pre-folded by using the first sheath, then the pump head is further folded to a folded state by using the second sheath, a step-by-step folding mode is used, the folding difficulty is small, the pump head is not easy to damage in the folding process, the pushing process is smoother, meanwhile, the length of the first sheath is shorter, the support and the impeller of the pump head are folded into the first sheath, and the strokes of folding the pump head into the first sheath and transferring the pump head from the first sheath to the second sheath are correspondingly shortened, so that the damage of the pump head is further reduced;

The technical features of the above embodiments may be arbitrarily combined, and all possible combinations of the technical features in the above embodiments are not described for brevity of description, however, as long as there is no contradiction between the combinations of the technical features, they should be considered as the scope of the description.

The foregoing examples illustrate only a few embodiments of the utility model, which are described in detail and are not to be construed as limiting the scope of the utility model. It should be noted that it will be apparent to those skilled in the art that several variations and modifications can be made without departing from the spirit of the utility model, which are all within the scope of the utility model. Accordingly, the scope of protection of the present utility model is to be determined by the appended claims.

Claims

1. An interventional assembly for a catheter pump, the catheter pump comprising:

a conduit;

a drive shaft rotatably penetrating the guide tube;

the interventional assembly comprises:

a third sheath configured to be partially inserted into the vasculature of a subject through the puncture and having a proximal end operably interfacing with a distal end of the second sheath, with a third passageway; at least part of the pump head is transferred from the second channel into the third channel in a collapsed state by pushing the catheter forward.

2. The catheter pump access assembly of claim 1, wherein an inner diameter of the second channel is smaller than an inner diameter of the first channel.

3. The catheter pump access assembly of claim 1, wherein an inner diameter of the third channel is approximately equal to an inner diameter of the second channel.

4. The catheter pump intervention package of claim 1, wherein the pump housing comprises a stent, the distal end of the stent being connected to a protective tip; the length of the first channel is greater than the length of the stent in the collapsed state but less than the sum of the length of the stent in the collapsed state and the guard tip.

5. The catheter pump access assembly of claim 4, wherein a sum of lengths of the first and second channels is greater than a sum of lengths of the stent and the guard tip in the collapsed state.

6. The catheter pump intervention package of claim 5, wherein a hemostatic valve is disposed proximally within said third channel;

7. The catheter pump access assembly of claim 4, wherein a length of the second channel is greater than a sum of a length of the stent and the guard tip in the collapsed state.

8. The catheter pump intervention package of claim 7, wherein a hemostatic valve is disposed proximally within said third channel;

9. A catheter pump, comprising: a catheter pump, and an intervention assembly adapted to intervene the catheter pump in a vasculature of a subject;

the catheter pump includes:

a conduit;

a drive shaft rotatably penetrating the guide tube;

a collapsible pump head that can be delivered to a desired location of the heart through the catheter to pump blood, comprising a pump housing connected to a distal end of the catheter, an impeller received in the pump housing; the impeller being received within a cradle of the pump housing and connected to a distal end of the drive shaft, a proximal end of the drive shaft being connectable to a motor to transmit rotation of the motor to the impeller;

the interventional assembly comprises: