CN113974778B

CN113974778B - Crimping type multistage developing and thrombus taking support system

Info

Publication number: CN113974778B
Application number: CN202111438500.XA
Authority: CN
Inventors: 吴健平; 赵杰; 顾怡; 曹维拯; 张剑钦; 王国辉; 李志刚
Original assignee: Shanghai Xinwei Medical Technology Co ltd
Current assignee: Shanghai Xinwei Medical Technology Co ltd
Priority date: 2021-11-30
Filing date: 2021-11-30
Publication date: 2023-09-22
Anticipated expiration: 2041-11-30
Also published as: WO2023284890A1; CN113974778A

Abstract

The invention provides a crimping type multistage developing and thrombus taking support system, which comprises a support, a pushing rod and an introducing sheath, wherein the pushing rod is arranged on the support; the stent is coiled, the diameter of the stent can be automatically adjusted according to the diameter of the blood vessel, so that the stent is more beneficial to attaching thrombus and the wall of the blood vessel and avoiding the damage of the blood vessel by the stent; the bracket is connected with a bracket far-end developing mark and a bracket intermediate developing mark, and the bracket intermediate developing mark is arranged according to a preset axial distance from the bracket far-end developing mark; the bracket is fixedly connected with the pushing rod, and a near-end developing mark is arranged at the fixed connection part; the stent can be used for better judging the stent unfolding state and the thrombus embedding state by a doctor, and the effective length of the stent for capturing thrombus and the position of the thrombus can be effectively marked. The invention also discloses a plurality of connection modes of the bracket and the pushing rod, which are beneficial to improving the connection strength and the conveying performance between the bracket and the pushing rod.

Description

Crimping type multistage developing and thrombus taking support system

Technical Field

The invention belongs to the field of medical appliances, and particularly relates to a crimping type multistage developing thrombus taking support system.

Background

Cerebral apoplexy is also called cerebral apoplexy, is a local brain dysfunction caused by acute cerebrovascular diseases, has the characteristics of high morbidity, high mortality, high disability rate and high recurrence rate after more than 24 hours, and is good for people over 50 years old. At present, the incidence rate of cerebral apoplexy in China rises year by year and becomes the first cause of death in China.

At present, the main treatment means for ischemic stroke is drug thrombolysis and interventional instrument thrombolysis, and the adoption of drug thrombolysis within 4-5 hours of onset is the preferred scheme for treating acute ischemic stroke, but because the time window is too short, few cerebral stroke patients meet the treatment conditions of drug thrombolysis. Meanwhile, due to the factors of short treatment time window, low vascular recanalization rate, high incidence rate of beginner complications and the like, the thrombolysis of the interventional instrument gradually develops, and has good application prospect in clinic. The therapeutic mode of interventional instrument thrombus removal has wider applicability, can rapidly recanalize occluded blood vessels, reduces the incidence rate of drug complications and improves the prognosis of patients.

In the prior patent CN210541719U, the support rod body is disconnected, and the integral connection is fixed by virtue of the developing point. During operation, the stent is contracted in the sheath tube smaller than 1mm, once the stent is released, the diameter of the stent is instantaneously expanded to 3-8mm, the diameter of the stent suddenly changes greatly, and the position of a developing point is easily broken. The broken part can directly scratch the blood vessel, causes spasm, and the developing material has the risk of dropping in the human body.

Although there are a variety of stent grafts that use visualization wires to penetrate the entire stent to perform visualization, during surgery, the physician cannot be provided with the effective working length of the stent to capture thrombus. The crimping design of the stent has no clear requirement, and the adherence of the stent cannot be ensured in actual use, so that the capturing effect of thrombus can be influenced or the vessel wall can be damaged.

In addition, the connection design mode between the bracket and the pushing rod is also ambiguous, and the connection strength and the conveying performance of the two brackets can be influenced, so that the thrombus taking performance of the bracket is influenced, and the accuracy and the efficiency in operation are influenced.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides a crimping type multistage developing and thrombus taking support system.

It must be noted that, as used herein and in the appended claims, distal refers to the end that is distal from the operator (e.g., physician), and proximal refers to the end that is proximal to the operator (e.g., physician), unless the context clearly dictates otherwise.

Mechanical bonding in this context means that the two elements are mechanically bonded, including by mechanical bonding themselves, or by bolting and riveting, etc.

The coiled multi-section developing thrombus taking support system is characterized by comprising a support, a pushing rod and an introducing sheath; the bracket is coiled; the bracket is connected with a bracket far-end developing mark and a bracket intermediate developing mark, and the bracket intermediate developing mark is arranged according to a preset axial distance from the bracket far-end developing mark; the support is fixedly connected with the pushing rod, and a near-end developing mark is arranged at the fixed connection position.

Preferably, the stent distal end development mark is connected to the stent distal end, and the number of stent distal end development marks is equal to or less than the number of end heads of the stent distal end.

Preferably, the stent distal end development marker is a hollow structure, and the stent distal tip is located in a hollow portion thereof.

Preferably, the distal end of the stent distal end development marker is a continuous smooth transition shape.

Preferably, the bracket intermediate development mark is connected with a bracket arm of the effective length part of the bracket.

Preferably, m rows of the intermediate development marks of the bracket are arranged along the axial direction of the bracket, wherein m is more than or equal to 1; the middle developing marks of each row of brackets are arranged according to the preset axial distance between the middle developing marks and the far-end developing marks at the far ends of the brackets; and n support middle developing marks are approximately uniformly distributed in the circumferential direction of the m rows of middle developing supports, wherein n is more than or equal to 2. Preferably, the bracket intermediate developing mark is a hollow structure, and the bracket arm of the bracket effective length portion is located in the middle portion thereof.

Preferably, the bracket intermediate developing mark is wound around the bracket arm to be tubular, and the winding number is between 5 and 15; or the length of the intermediate development mark of the bracket is between 0.05 and 0.01 mm.

Preferably, two ends of the support intermediate developing mark are provided with support arm limiting mechanisms, the support arm limiting mechanisms are part of support arms, and the width of each support arm limiting mechanism is larger than the diameter of the support intermediate developing mark.

Preferably, a fixed attachment mechanism for connecting the bracket intermediate developing mark is arranged on the bracket arm of the effective length part of the bracket, the fixed attachment mechanism extends out of the main body axis of the bracket arm, and the bracket intermediate developing mark is connected with the fixed attachment mechanism.

Preferably, the push rod distal end comprises a first connection segment, a second connection segment, and a first bend between the first connection segment and the second connection segment; the proximal end of the stent comprises a first stent converging portion and a first stent projecting portion, and a stent proximal end hole positioned on the first stent projecting portion, wherein the width of the first stent projecting portion is smaller than that of the first stent converging portion, and the first stent converging portion, the first stent projecting portion and the stent proximal end hole have the same symmetrical plane; the first bend passes through the stent proximal aperture such that the first and second connection segments are located on either side of the first stent tab.

Preferably, the push rod distal end comprises a push rod connection; the proximal end of the stent comprises a second stent convergence and a second stent protrusion, and the second stent protrusion width is less than the second stent convergence width; the end face of the push rod connecting part is connected with the end face of the second bracket protruding part.

Preferably, the proximal end of the stent comprises a third stent convergence, a stent protruding connection and a third stent protruding end connected in sequence, wherein the third stent convergence width is greater than the third stent protruding end width, and the third stent protruding end width is greater than the stent protruding connection width;

the distal end of the pushing rod comprises a third connecting section, a fourth connecting section and a second bending part; the second bending part surrounds the bracket protruding connecting part and is connected with the third connecting section and the fourth connecting section which are respectively positioned at two sides of the bracket protruding connecting part.

Preferably, the push rod comprises a push rod body, a push rod developing spring and a heat shrinkage film.

Preferably, the near end of the push rod body is provided with P developing mark points, and P is more than or equal to 1.

Preferably, the distal diameter of the push rod body is smaller than the intermediate diameter, and the intermediate diameter is continuously and smoothly reduced to the distal diameter.

Preferably, the push rod body is nickel titanium and/or stainless steel material.

Preferably, the stent is a nickel titanium alloy.

Preferably, the stent distal development marker, the stent intermediate development marker and the proximal development marker are selected from one of platinum iridium, platinum dock, tantalum, gold.

Preferably, the developing mark is fixedly connected with the bracket or the push rod in a glue bonding, welding or mechanical combination mode.

Compared with the prior art, the invention has the beneficial effects that:

1. the diameter of the stent can be automatically adjusted according to the diameter of the blood vessel, so that the stent is more beneficial to attaching thrombus and the wall of the blood vessel and avoiding the damage of the blood vessel by the stent;

2. the method can enable doctors to better judge the expanded state of the stent and the embedded state of thrombus, and effectively mark the effective length of the stent for capturing thrombus and the position of the thrombus;

3. the connection strength and the conveying performance between the bracket and the pushing rod can be improved.

Drawings

Fig. 1 is a schematic view of the overall structure of a crimping multi-stage developing and thrombus-removing stent system according to the present invention.

Fig. 2 is a sectional view of a crimped stent.

Fig. 3 is a schematic illustration of a rolled stent tiling.

Fig. 4 is a schematic view of a distal end development mark structure of a stent in one embodiment.

FIG. 5 is a schematic diagram of a structure of a support intermediate development mark in one embodiment.

FIG. 6 is a diagram of a bracket intermediate development point boss design in one embodiment.

FIG. 7 is a diagram of a stent development marker design in one embodiment.

Fig. 8 is a schematic diagram of an alternative embodiment of a stent development mark design.

Fig. 9A1 is a schematic view of a connection between a bracket and a push rod in an embodiment.

Fig. 9A2 is a cross-sectional view of fig. 9 A1.

Fig. 9B is a schematic illustration of the connection of the stent, push rod and collar in one embodiment.

Fig. 10 is a schematic view of the proximal end of the stent of fig. 9A and 9B.

Fig. 11A is a schematic view of a connection between a bracket and a pushing rod in an embodiment.

Fig. 11B is a schematic illustration of the connection of the stent, push rod and collar in one embodiment.

Fig. 12A is a schematic view of a connection between a bracket and a pushing rod in an embodiment.

Fig. 12B is a schematic view of the distal end of the push rod of fig. 12A.

Fig. 12C is a schematic illustration of a stent, push rod and collar connection in one embodiment.

Fig. 13A, 13B, and 13C are schematic views of bending widths at different bending angles.

Fig. 14 is a schematic view of a push rod in one embodiment.

Fig. 15 is a schematic view of a development of a thrombolytic system.

Detailed Description

The invention will be further described with reference to the accompanying drawings and specific embodiments, to which the invention is not limited. Variations and advantages that would occur to one skilled in the art are included within the invention without departing from the spirit and scope of the invention, and the scope of the invention is defined by the appended claims.

Fig. 1 illustrates one embodiment of a crimped multi-segment development thrombolysis stent system according to the present invention. The thrombus taking support system comprises a support 4, a pushing rod 1 and an introducing sheath 2. The stent 4 can automatically adjust the size along with the diameter of the blood vessel, is more beneficial to attaching thrombus and the blood vessel wall and avoids the damage of the blood vessel by the stent. The stent 4 comprises a stent distal end developing mark 6 and a stent middle developing mark 5. The bracket 4 is fixedly connected with the push rod 1, and a near-end developing mark is arranged at the fixed connection part.

The support 4 has a tubular or substantially cylindrical shape. In other embodiments, the stent 4 may have a shape that is neither tubular nor cylindrical. In some embodiments, the stent 4 may have open proximal and distal ends, for example, as shown in fig. 1, while in other embodiments, the stent 4 may have open or closed proximal and/or distal ends.

As shown in fig. 2, in some embodiments, the stent 4 may be crimped, rolled, or otherwise shaped such that the stent first edge 41 and the stent second edge 42 overlap each other when the stent 4 is in a reduced volume configuration. The stent 4 has a greater degree of overlap and a smaller diameter D when the stent is in the delivery configuration; when the stent 4 is in the deployed configuration, the stent 4 has a reduced degree of overlap or no overlap and the diameter D is greater.

The support 4 can be self-expanding or can be expanded under the action of external force. In some embodiments, the stent 4 is a shape memory alloy or super elastic material, preferably the stent 4 is a nickel titanium alloy. The stent 4 may thus be deployed from the delivery configuration toward the fully deployed configuration upon release of the delivery catheter (not shown). The diameter of the stent 4 in the deployed configuration depends, at least in part, on the size of the vessel in which it is positioned and the number and nature of the thrombus contacted.

In some embodiments, the expandable portion of the stent 4 comprises a mesh structure comprised of a plurality of cells. For example, the expandable portion of the stent 4 shown in fig. 3 includes a plurality of stent arms 43 and a plurality of cells 44.

Preferably, the cells of the stent 4 are of closed loop design.

Preferably, the plurality of holder arms 43 can be formed to have a particular corrugated or sinusoidal shape along the general axis of the holder 4. In some embodiments, however, the plurality of support arms 43 may have additional shapes.

The stent effective length portion 45 is L1 in length. In some embodiments, the stent effective length portion 45 is capable of contacting, capturing thrombus with individual cells 44 and/or the outer or radially outer portions of the deployed stent 4. The stent non-effective length portion 46 may include a tapered stent proximal portion. The tapering of the proximal portion of the stent can facilitate retrieval and repositioning of the thrombolytic device.

The whole bracket 4 can be formed by laser engraving, and a plurality of bracket arms can be welded into a whole. Further, the stent 4 is subjected to working procedures such as heat treatment and polishing after being molded, so that the mechanical property of the stent is improved, burrs of the stent body are removed, the surface is brighter, and the damage to the vessel wall is avoided.

As shown in fig. 1 and 3, the stent distal end development mark 6 is located at the distal end of the stent 4, and its specific number may be set according to the number of tips of the distal end of the stent 4, and may be equal to or less than the number of tips.

The stent distal development marker 6 is a hollow structure, as shown in fig. 4, and in some embodiments the stent distal development marker 6 is hollow spring-like, and in other embodiments it may be hollow tubular, without limitation, and configured such that the stent distal tip is in its central portion.

In some embodiments, the stent distal development marker 6 is attached to the stent distal tip by adhesive, welding, or mechanical bonding (e.g., crimping).

Preferably, the bonding glue comprises a UV glue and/or an epoxy glue.

Preferably, the distal end of the stent distal end visualization mark 6 is a continuous smooth transition shape, which can avoid vascular injury during surgery. Preferably, the distal end of the stent distal end development marker 6 is hemispherical.

The carriage intermediate development mark 5 is connected to a non-terminal carriage arm 43 for a portion of the effective length of the carriage 4. In some embodiments, the stent middle developing marks 5 are arranged in m rows along the axial direction of the stent 4, wherein m is greater than or equal to 1, and the stent middle developing marks 5 of different rows are arranged at different preset axial distances from the stent distal developing marks 6 along the stent 4. The axial distance between the bracket intermediate developing mark 5 and the bracket far-end developing mark 6 along the bracket 4 refers to the axial distance between the circumference of the bracket intermediate developing mark 5 and the circumference of the bracket far-end developing mark 6 along the bracket 4. For example, as shown in fig. 3, the axial distance between the distal-most stent-intermediate developing mark 5 and the stent-distal developing mark 6 along the stent 4 is S1, and the value of S1 is set according to a specified design value.

Preferably, when m.gtoreq.2, the axial distance along the axis of the stent 4 between the most distal stent-intermediate developing mark 5 and the stent-distal developing mark 6 is equal to the axial distance along the axis of the stent 4 between each adjacent column of stent-intermediate developing marks 5. The axial distance along the axis of the holder 4 between the respective rows of the holder intermediate development marks 5 is the axial distance along the holder 4 between the circumferences where the respective rows of the holder intermediate development marks 5 are located. For example, as shown in fig. 3, the axial distance between the two-row rack intermediate developing marks 5 is S2, and the values of S2 are set in accordance with the specified design values. S1=s2 when the axial distance along the axis of the stent 4 between the most distal stent-intermediate developing mark 5 and the stent-distal developing mark 6 is equal to the axial distance along the axis of the stent 4 between the two rows of stent-intermediate developing marks 5.

N bracket intermediate developing marks 5 are approximately uniformly distributed in the circumferential direction of the same axial position, wherein n is more than or equal to 2; preferably, n=3. The circumferential direction of the same axial position means that the n intermediate developing marks 5 are approximately on the circumference of the same axial position, and the n intermediate developing marks 5 are approximately distributed near the circumference of the same axial position due to the convenience of design and arrangement, processing errors and other factors, or the circumference formed by the n intermediate developing marks 5 is basically perpendicular to the axis of the support 4, or has small angle deviation.

For example, as shown in fig. 3, m=2, the axial distance between the distal intermediate development mark 51 and the proximal intermediate development mark 52 and the distal development mark 6 is known, and the axial distance between the proximal intermediate development mark 52 and the distal intermediate development mark 51 is the same as the axial distance of the distal intermediate development mark 51 and the distal development mark 6. Thus, since the axial distance between the development marks is known, the stent 4 can be a scale for measuring thrombus length, the stent distal development mark 6 is the starting point of the scale, and the stent intermediate development marks 5 at different axial positions are the full-point graduation marks on the scale. When a thrombus is in the stent, the length of the thrombus can be measured approximately because the axial distance between the imaging markers is known.

When n stent intermediate development marks 5 are uniformly arranged in the circumferential direction of the same axial position, wherein n is not less than 2, the distance between the intermediate development marks 5 at the same axial position is small because the stent 4 is small in diameter in the delivery configuration; when the stent 4 is changed from the delivery configuration to the deployment configuration, the stent 4 may become several times, for example, 4 times, or even more, so that the distance between the intermediate development marks 5 at the same axial position may become much larger than that in the delivery configuration, and the doctor can judge the deployment state of the stent 4 accordingly.

The bracket intermediate development mark 5 is a hollow structure, which may be hollow spring-like in some embodiments, and hollow tubular in other embodiments, without limitation, and is configured to fit over the bracket arm.

Fig. 5 shows a specific embodiment of the stent-intermediate development marker 5. The bracket intermediate development mark 5 is wound in a tubular shape around the bracket arm 43, the bracket arm 43 passes through the bracket intermediate development mark 5, and the axis of the bracket intermediate development mark 5 is substantially coincident with the bracket arm 43 around which it is wound.

Preferably, two ends of the support intermediate developing mark 5 are provided with support arm limiting mechanisms, and the support arm limiting mechanisms are part of support arms. The holder arm limit mechanism is disposed on the holder arm 43 to which the holder intermediate development mark 5 is attached at the time of laser engraving of the holder 4. Preferably, in some embodiments, the carriage arm spacing mechanism is shaped as shown in fig. 6, with the width of the carriage arm spacing mechanism 43A being greater than the inner and/or outer diameter of the carriage intermediate development mark 5, such that movement of the carriage intermediate development mark 5 on the carriage rod is avoided.

In some embodiments, the bracket intermediate development mark 5 is attached to the bracket arm 43 by bonding or welding.

Preferably, the bonding glue comprises a UV glue and/or an epoxy glue.

Preferably, the stent intermediate development mark 5 is wound between 5 and 15 turns using a development material.

Preferably, the length of the stent intermediate development mark 5 is between 0.05 and 0.1 mm.

Preferably, the corner end of the holder arm limit mechanism 43A transitions smoothly. Preferably, the corner end of the holder arm limit mechanism 43A is a smooth circular arc.

Further, the specific design dimensions are as follows:

support arm spacing mechanism 43A width W1:0.01-1.5mm;

the arc R2 at the corner end of the support arm limiting mechanism 43A is 0.02-0.9mm;

the spacing L4 of the support arm limiting mechanism 43A is 0.02-0.9mm.

Fig. 7 and 8 show further embodiments of the stent-intermediate development marker 5. The holder arm 43 has a fixed attachment mechanism 43B for connecting the holder intermediate development mark 5. The bracket intermediate development mark 5 is connected to the fixed attachment mechanism 43B, and the bracket intermediate development mark 5 is located outside the main body axis of the bracket arm 43. Preferably, the fixed attachment mechanism is a two-point fixed attachment mechanism.

In some embodiments, as shown in fig. 7, the fixing attachment mechanisms 43B are perforated structures protruding from the axis of the body of the support arm 43, the support intermediate developing marks 5 are located between the fixing attachment mechanisms 43B, and each support arm of the support intermediate developing marks 5 extends along the axis of the body of the support arm 43, and is connected to the holes of the fixing attachment mechanisms 43B, so that the support intermediate developing marks 5 are connected to the fixing attachment mechanisms 43B by bonding, welding or mechanical bonding.

In other embodiments, as shown in FIG. 8, the fixed attachment mechanism 43B is a cantilevered structure that projects from the body axis of the holder arm 43. Preferably, the fixed attachment mechanism 43B is an "L" cantilever structure, and the bracket intermediate development mark 5 is tubular or substantially wound in a tubular shape, located intermediate the two cantilevers. One end of an L-shaped cantilever of the fixed attachment mechanism 43B is connected with the main body of the bracket arm 43, the other end of the L-shaped cantilever extends into a tube cavity of the bracket intermediate developing mark 5, and the bracket intermediate developing mark 5 is connected with the fixed attachment mechanism 43B in an adhesive, welding or mechanical combination mode.

The proximal end of the bracket 4 is fixedly connected with the distal end of the push rod 1.

Fig. 9A1, 9A2 and 9B show a specific embodiment of the connection of the holder 4 to the push rod 1. Fig. 9A2 is a cross-sectional view of fig. 9A1 along the plane P1. In fig. 9A1, 9A2 and 9B, the distal end of the push rod 1 is a push rod connection 120 comprising a first connection segment 121, a second connection segment 122 and a first bend 123 between the first connection segment 121 and the second connection segment 122. The push rod connection 120 is generally "U" shaped, the first 121 and second 122 connection segments being substantially straight, the first 123 bend being about 180 degrees.

Fig. 10 is a schematic view of the proximal junction of the respective stents of fig. 9A1, 9A2 and 9B. The proximal end of the stent 4 comprises a first stent converging section 401, a first stent protruding section 402 and a stent proximal end hole 403, and the first stent converging section 401, the first stent protruding section 402 and the stent proximal end hole 403 have the same longitudinal symmetry plane P1 (as shown in FIG. 9A 1), the first stent protruding section 402 is the distal end portion of the stent proximal end, and the stent proximal end hole 403 is located on the first stent converging section 401. The width of the first bracket projection 402 is smaller than the width of the first bracket convergence 401. The longitudinal symmetry plane P1 passes through the axis of the push rod 1 and is perpendicular to the upper and lower surfaces of the proximal connection of the stent.

Preferably, the proximal dimension of the stent 4 is as follows:

the width H1 of the bracket protruding part 402 is 0.02-0.9mm;

the width H2 of the bracket convergence part 401 is 0.05-1.2mm;

the length L2 of the bracket protruding part 402 is 0.03-0.8mm;

the length L3 of the bracket convergence part 401 is 0.03-1mm;

the radius R1 of the proximal stent hole 403 is 0.01-0.9mm.

The stent proximal hole 403 is sized and shaped to be slightly larger than the cross-section of the first bend 123, allowing the first bend 123 to pass therethrough such that the first and second connection segments 121 and 122 are each located on a different side of the first stent tab 402.

Fig. 11A and 11B show a further embodiment of the connection of the holder 4 to the push rod 1. Distal to the push rod 1 in fig. 11A is a push rod connection 130, and the proximal portion of the stent 4 includes a second stent convergence 411 and a second stent protrusion 412. Preferably, the second bracket converging portion 411 and the second bracket protruding portion 412 have the same longitudinal symmetry plane. The second bracket protruding portion 411 is a proximal-most portion of the bracket, the second bracket protruding portion 412 includes an end surface connected to the push rod connection portion 130, and the shape of the second bracket protruding portion 412 may be square as shown in fig. 12A or may be other shapes, but the overall width of the second bracket protruding portion 412 is smaller than the width of the second bracket converging portion 411.

The end face of the second bracket protruding portion 412 and the end face of the push rod connecting portion 130 are connected in a glue bonding or welding mode, so that the end face of the second bracket protruding portion 421 and the end face of the push rod connecting portion 130 are connected together, and therefore the bracket 4 and the push rod 1 are connected together, and the push rod 1 and the bracket 4 are fixedly connected. The connecting mode has the characteristics of simple structure and convenient manufacture.

Fig. 12A and 12C show another embodiment of the connection between the bracket 4 and the push rod 1, and fig. 12B is a schematic view of the distal end of the push rod 1 in fig. 12A and 12C, where the bracket 4 and the push rod 1 are connected by glue bonding or welding. The proximal portion of the stent 4 in fig. 12A includes a third stent converging portion 421 and a third stent protruding portion 422, wherein the third stent protruding portion 422 includes a third stent protruding end portion 422A and a stent protruding connecting portion 422B. The third bracket projecting end 422A is the nearest end of the bracket 4, and the bracket projecting connecting portion 422B connects the third bracket projecting end 422A with the third bracket converging portion 421. Preferably, the third bracket convergence 421, the third bracket protruding end 422A and the bracket protruding connection 422B have the same longitudinal symmetry plane. The third bracket protruding portion 422 is overall T-shaped, and the bracket protruding connecting portion 422B has a width smaller than the third bracket protruding end portion 422A, and the third bracket protruding end portion 422A has a width smaller than the third bracket converging portion 421.

Distal to the push rod in fig. 12A and 12B is a push rod connection 140, the push rod connection 140 comprising a third connection segment 141, a fourth connection segment 142, and a second bend between the first connection segment 141 and the second connection segment 142, which in turn may be divided into a second a bend 143, a second B bend 144, and a second C bend 145. The second bend is located between the third bracket converging portion 421 and the third bracket projecting end portion 422A.

Fig. 13A, 13B and 13C show schematic views of different bend angles and widths. Fig. 13A is a schematic view of the curvature of the bending portion being 180 °, M1 and M2 being the widths of different portions of the bending portion, the curvature being a bending portion of 180 °, the bending width gradually increasing from M1 to M2, and then the bending width remaining unchanged. Fig. 13B is a schematic view of a curvature of the curvature being greater than 90 ° and less than 180 °, M3 and M4 being widths of different portions of the curvature, the curvature being greater than 90 ° and less than 180 °, the curvature width gradually increasing from M3 to M4, the curvature being maximum at the open end of the curvature. Fig. 13C is a schematic view of the bending portion having a bending degree of more than 180 °, M5, M6 and M7 are widths of different portions of the bending portion, the bending portion having a bending degree of more than 180 ° is gradually increased from M5 to M6, and gradually decreased from M6 to M7 until gradually decreased to an opening end of the bending portion, and M6 is a maximum portion of the bending width of the bending portion.

The third connection section 141 is an axial extension along the shaft body of the push rod 1, the fourth connection section 142 is substantially parallel to the third connection section 142, and the minimum distance between the third connection section 141 and the fourth connection section 142 is smaller than the width of the third bracket protruding end 422B. The plane in which the central bending axis portion of the second C-bend 145 lies is substantially perpendicular to the axis of the third connecting section 141 and the axis of the fourth connecting section 142. The second a-bend 143 connects the third connection section 141 with one end of the second C-bend 145, and the second B-bend 144 connects the fourth connection section 142 with the other end of the second C-bend 145. Preferably, the curvature of the second a-curved portion 143 and the second B-curved portion 144 is 90 ° or less, the curvature of the second C-curved portion 145 is greater than 90 °, and further, the curvature of the second C-curved portion 145 may be greater than 180 °. When the curvature of the second C-bend 145 is greater than 180 °, the second C-bend 145 has a region where the bending width gradually decreases, that is, the bending width gradually decreases from the maximum bending width to the opening width of both side ends of the second C-bend 145. Preferably, the curvature of the second C-bend 145 is 180 °.

The third connection section 141 and the second a-bend 143 are located at one side of the bracket protruding connection 422B, the fourth connection section and the second B-bend 144 are located at the other side of the bracket protruding connection 422B, and the second C-bend 145 surrounds the bracket protruding connection 422B, i.e., both ends of the second C-bend 145 are respectively located at both sides of the bracket protruding connection 422B, but the middle portion is located above the bracket protruding connection 422B, i.e., the bracket protruding connection 422B is located in the bent portion of the second C-bend 145, thereby connecting the second a-bend 143 and the second B-bend 144. The maximum width of the bent portion of the second C-shaped bent portion 145 is greater than the width of the bracket projection connecting portion 422B, so that it is ensured that the second C-shaped bent portion 145 can surround the bracket projection connecting portion 422B and connect the first a-shaped bent portion 143 and the second B-shaped bent portion 144 on both sides of the bracket projection connecting portion 422B; the maximum width of the bent portion of the second C-bend 145 is smaller than the width of the third bracket projection end 422A, so that the second C-bend 145 is defined between the bracket projection end 422A and the third bracket convergence 421.

Thus, the second bending portion formed of the second a bending portion 143, the second B bending portion 144, and the second C bending portion 145 is one "U" shape. The maximum width of the "U" shaped portion is less than the width of the stent protruding end portion 422A such that the "U" shaped portion is defined between the third stent protruding end portion 422A and the third stent converging portion 421; the maximum width of the "U" shaped portion is greater than the width of the stent protruding connection 422B so that the stent protruding connection 422B can be located in the "U" shaped portion. Therefore, the support 4 and the pushing rod 1 have a mechanical matching relationship, and the support and the pushing rod are not easy to fall off.

As shown in fig. 9B, 11B and 12C, a developing ring 3 is sleeved outside the joint between the distal end of the stent 4 and the distal end of the push rod 1, so that the connection strength of the push rod 1 and the stent 4 is increased, the smoothness of the connection part is increased, the possible damage of the connection part to the blood vessel is reduced, and meanwhile, the developing ring 3 is used as a proximal developing mark.

Preferably, a proper amount of glue is injected at two ends of the developing ring 3, so that the connection strength of the bracket 4 and the pushing rod 1 is increased.

Preferably, the glue comprises a UV glue and/or an epoxy glue.

The whole proximal end of the support 4 is symmetrically designed, and the connection part of the push rod 1 and the support 4 is also symmetrical, so that when the support 4 is pushed, the force transmission direction between the push rod 1 and the support 4 is basically consistent with the symmetry axis, the phenomenon that the left and right stress of the distal end of the rod body of the push rod 1 is unbalanced in the asymmetric design is avoided, the push rod 1 and the support 4 are prevented from being connected to deviate, and stable pushing of the support 4 can be better realized.

Fig. 14 shows a specific embodiment of a push rod. The push rod 1 consists of a push rod body 11, a push rod developing spring 12 and heat shrinkage films 13 and 14. The proximal end of the push rod body 11 is provided with P marking points 15, and n is more than or equal to 1, so that a doctor can conveniently judge the state that the stent enters the microcatheter. The pushing rod developing spring 12 at the distal end of the pushing rod 1 plays a role in developing, and is not easy to deform or fold when passing through a bent blood vessel, so that the thrombus taking support is more beneficial to conveying.

Preferably, the length of the developing spring is 0.1-50mm.

Preferably, the marking point p=2 at the proximal end of the push rod body 11.

Preferably, wherein the distal end of the push rod body 11 has a smaller diameter than the middle end and the diameter is continuously and smoothly decreasing. The distal end of the push rod body 11 has a tapered region 111, and the diameter of the push rod body 11 is gradually reduced in the tapered region 111 and finally reduced to be equal to the diameter of the distal end 112 of the push rod body so as to smoothly transition when being connected with the proximal end of the bracket 4, thereby being more beneficial to force transmission and improving the conveying efficiency of products. In some embodiments, there is a distance between the terminus of the tapered region 111 and the distal end 112 of the push rod body. In other embodiments, the tapered region 111 terminates coincident with the push rod body distal end 112.

Because of the tapered region 111, the diameter of the push rod body 11 is reduced more gradually, and there is no stepped shape in which the diameter is reduced suddenly, so that stress concentration and breakage of the push rod body can be prevented.

Preferably, the push rod body is nickel titanium and/or stainless steel material;

preferably, the heat shrink films 13 and 14 are high molecular materials with low friction coefficients. Further preferably, the low coefficient of friction polymeric material comprises Polytetrafluoroethylene (PTFE) and/or poly (hexamethylene terephthalate) (PET) plastic.

Preferably, the heat shrink film length is 0.2-500mm.

In all of the above embodiments, the developing material uses noble metals such as platinum iridium, platinum dock, tantalum, gold, etc.

As shown in fig. 15, when the distal, intermediate and proximal development marks of the stent 4 are installed, the development marks take on a multi-stage development state under radiation. Because the distance between the stent middle developing marks 5 at different axial positions of the stent 4 is known during the expansion, a doctor can consider the stent 4 as a ruler with scales, and judge the position of thrombus and the length of embedded thrombus according to the ruler, thereby improving the success rate of the operation.

The foregoing detailed description of the preferred embodiments of the present invention has been provided for the purpose of illustrating the general principles and features of the present invention, and is not meant to limit the scope of the invention to those skilled in the art, who are able to understand the present invention and to implement it accordingly. It should be understood that numerous modifications and variations can be made in accordance with the concepts of the invention by one of ordinary skill in the art without undue burden. Therefore, all technical solutions which can be obtained by logic analysis, reasoning or limited experiments based on the prior art by the person skilled in the art according to the inventive concept shall be within the scope of protection defined by the claims.

Claims

1. The coiled multi-section developing thrombus taking support system is characterized by comprising a support, a pushing rod and an introducing sheath;

the bracket is coiled;

the bracket is connected with a bracket far-end developing mark and a bracket intermediate developing mark, and the bracket intermediate developing mark is arranged according to a preset axial distance from the bracket far-end developing mark;

the bracket is fixedly connected with the pushing rod, and a near-end developing mark is arranged at the fixed connection part;

the proximal end of the bracket comprises a third bracket convergence part, a bracket protruding connecting part and a third bracket protruding end part which are sequentially connected, wherein the width of the third bracket convergence part is larger than that of the third bracket protruding end part, and the width of the third bracket protruding end part is larger than that of the bracket protruding connecting part;

2. The thrombolytic stent system according to claim 1, wherein said stent distal development marker is connected to said stent distal tip, said stent distal development marker being equal to or less in number than the number of tips of said stent distal tip.

3. The thrombolytic stent system according to claim 2, wherein said stent distal development marker is a hollow structure, said stent distal tip being located in a hollow portion thereof.

4. The embolectomy stent system of claim 3, wherein the distal end of the stent distal end visualization marker is a continuous smooth transition shape.

5. The thrombolytic stent system of claim 1, wherein said stent intermediate development marker is connected to a stent arm of said stent active length portion.

6. The thrombolytic stent system according to claim 5, wherein said stent intermediate development marks are arranged in m columns along the axial direction of the stent, wherein m is equal to or greater than 1;

the middle developing marks of each row of brackets are arranged according to the preset axial distance from the developing marks at the far ends of the brackets; and n support middle developing marks are approximately uniformly distributed in the circumferential direction of the m rows of middle developing supports, wherein n is more than or equal to 2.

7. The thrombolytic stent system according to claim 6, wherein said stent intermediate development marker is a hollow structure, and wherein a stent arm of said stent effective length portion is located in a central portion thereof.

8. The thrombolytic stent system of claim 7, wherein said stent intermediate development marker is wrapped around said stent arm in a tubular shape with a number of wraps between 5 and 15 turns; or (b)

The length of the intermediate development mark of the bracket is between 0.05 and 0.01 mm.

9. The thrombolytic stent system according to claim 7, wherein said stent intermediate development marker has stent arm stop mechanisms at both ends, said stent arm stop mechanisms being part of a stent arm, said stent arm stop mechanisms having a width greater than a diameter of said stent intermediate development marker.

10. The thrombolytic stent system according to claim 5, wherein a stent arm of said stent effective length portion has a fixed attachment mechanism for connecting a stent intermediate development marker, said fixed attachment mechanism extending beyond a stent arm body axis, said stent intermediate development marker being connected to said fixed attachment mechanism.

11. The thrombolytic stent system of claim 1, wherein said pusher comprises a pusher rod body, a pusher rod development spring and a heat shrink film.

12. The thrombolytic stent system according to claim 11, wherein said proximal end of said pusher rod has P development marker points, P.gtoreq.1.

13. The embolic stent system of claim 11 or 12, wherein the distal diameter of the push rod body is smaller than the mid-end diameter, and the mid-end diameter is continuously smoothly reduced to the distal diameter.

14. The thrombolytic stent system according to claim 11, wherein said push rod body is a nickel titanium and/or stainless steel material.

15. The thrombolytic stent system of claim 1, wherein said stent is nitinol.

16. The thrombolytic stent system of claim 1, wherein said stent distal development marker, said stent intermediate development marker and said proximal development marker are selected from one of platinum iridium, platinum dock, tantalum, gold.

17. The thrombolytic stent system according to claim 1, wherein the developing mark is fixedly connected with the stent or the push rod by means of glue bonding, welding or mechanical bonding.