WO2023087475A1

WO2023087475A1 - Thrombectomy device

Info

Publication number: WO2023087475A1
Application number: PCT/CN2021/139665
Authority: WO
Inventors: 刘载淳; 黄定国
Original assignee: 上海腾复医疗科技有限公司
Priority date: 2021-11-17
Filing date: 2021-12-20
Publication date: 2023-05-25

Abstract

A thrombectomy device, comprising: a thrombus removal stent (1), an inner tube (3) and a push tube (4), wherein the inner tube (3) is arranged in the thrombus removal stent (1) and the push tube (4) in a penetrating manner, a distal end of the inner tube (3) is connected to a distal end of the thrombus removal stent (1), and the inner tube (3) is axially movable relative to the push tube (4); a proximal end of the thrombus removal stent (1) is connected to a distal end of the push tube (4); and the thrombus removal stent (1) has an expandable and contractible stent structure and comprises a collection portion (11) and a cutting portion (12); and a distal end of the cutting portion (12) is smoothly connected to a proximal end of the collection portion (11), the collection portion (11) has a tubular structure that is closed at the distal end, and the cutting portion (12) has mesh openings in the circumferential wall and has an opening at the proximal end thereof. The thrombectomy device can improve the thrombectomy efficiency and a thrombectomy effect.

Description

Thrombectomy Device

cross reference

This application refers to the Chinese patent application No. 202111361012.3 entitled "Thrombectomy Device" submitted on November 17, 2021, which is incorporated by reference in its entirety into this application.

technical field

The present application relates to the technical field of medical devices, in particular to a thrombus removal device.

Background technique

Vascular disease has become the number one fatal disease in my country, and vascular embolism has become the main pathogenic factor in vascular disease. In particular, patients with ischemic stroke, pulmonary embolism, and lower extremity venous embolism have a total of more than 5 million new cases each year.

The use of thrombectomy device for interventional thrombectomy has many advantages such as less trauma, short postoperative recovery time, fewer complications after treatment, and good surgical effect, and is more acceptable to patients. Existing interventional thrombectomy programs mainly include catheter-based thrombolysis and thrombus aspiration. Thrombolytic therapy with catheters has the risk of causing cerebral hemorrhage or systemic hemorrhage, and thrombolysis with catheters for a long time also has the risk of infection. Suction thrombus removal involves a large amount of blood loss, and the effect of thrombectomy is limited, so anticoagulant therapy is still required after surgery. Therefore, it is still necessary to develop an interventional thrombectomy program that does not require the assistance of thrombolytic drugs during and after the operation, has less blood loss, shortens the operation time, and has a good thrombectomy effect.

Contents of the invention

The purpose of some embodiments of the present application is to provide a thrombus removal device to solve the problems of existing thrombus removal devices requiring drug assistance, large blood loss, long operation time and poor thrombus removal effect.

In order to solve the above technical problems, an embodiment of the present application provides a thrombus removal device, including: a thrombectomy bracket, an inner tube, and a pushing tube;

The inner tube is passed through the thrombus-retrieving bracket and the pushing tube, the distal end of the inner tube is connected to the distal end of the thrombus-retrieving bracket, and the inner tube can move axially relative to the pushing tube; The proximal end of the thrombus retrieval bracket is connected to the distal end of the push tube;

The thrombectomy stent is an expandable and contractible stent structure, and it includes: a collecting portion and a cutting portion; the distal end of the collecting portion is smoothly connected to the proximal end of the cutting portion, and the collecting portion is closed at the distal end In the tubular structure, the peripheral wall of the cutting part has a mesh and its proximal end has an opening.

In addition, the collection part is formed by interlacing braiding wires, and the cutting part is made by an integrated laser cutting process.

In addition, both the collecting part and the cutting part are made of the following materials: shape memory alloy and/or shape memory polymer material.

In addition, the distal end of the cutting part is provided with several connecting holes at intervals in the circumferential direction, and the collecting part is connected with the cutting part through the connecting holes through the braided wire at the proximal end.

In addition, a plurality of V-shaped rods are evenly spaced around the distal end of the cutting part; the closed ends of the V-shaped rods form arc-shaped connecting walls, and the connecting holes are opened in the arc-shaped connecting walls.

In addition, the connecting hole has a racetrack shape with an axial length smaller than a circumferential length.

In addition, the cutting portion includes a plurality of first V-shaped bars and a plurality of second V-shaped bars; the plurality of second V-shaped bars are smaller than the plurality of first V-shaped bars;

The plurality of first V-shaped rods are connected circumferentially and axially to form a cylindrical structure, and the plurality of first V-shaped rods form a plurality of first diamond-shaped meshes;

The plurality of first V-shaped rods includes a plurality of distal openings adjacent to the proximal end of the collection portion with nodes facing the proximal end adjoining the first V-shaped rods, and the nodes of the plurality of second V-shaped rods face the distal end and are respectively connected to the proximal ends of the collecting parts, and the two vertices of the opening ends of the plurality of second V-shaped rods are respectively connected to the first V-shaped rods adjacent to the far openings of the plurality of said second V-shaped rods; The V-shaped bar divides the peripheral wall of the cutting part between the distal opening adjoining the first V-shaped bar and the proximal end of the collecting part into two triangular meshes and a second diamond-shaped mesh.

In addition, the distal end of the cutting part is circumferentially provided with several connecting holes at intervals, and the collecting part is connected to the cutting part through the connecting holes through the braided wire at the proximal end;

The plurality of connection holes are respectively arranged on the nodes of the plurality of second V-shaped rods and the plurality of first V-shaped rods adjacent to the collecting part and the nodes are facing the distal end.

In addition, the cutting part also includes two first arc-shaped connecting rods and two second arc-shaped connecting rods;

A node at the proximal end of the cutting portion is connected to the first V-shaped rod at the distal end and two nodes axially connected to the first V-shaped rod at the proximal end are connected to form a third V-shaped rod. Rods, the distal ends of the two first arc-shaped connecting rods respectively connect with the proximal ends of the third V-shaped rods to form a first opening;

A node at the proximal end of the cutting portion is connected to the distal ends of the two second arc-shaped connecting rods respectively to form a second opening.

In addition, the thrombectomy bracket also includes a marking ring, the proximal ends of the two first arc-shaped connecting rods and the two second arc-shaped connecting rods converge and connect to the marking ring, and the marking ring is fixedly sleeved on the The distal end of the push tube.

In addition, the collection part includes a dense mesh weaving section and an open mesh weaving section; the dense mesh weaving section and the open mesh weaving section are arranged alternately along the axial direction or the dense mesh weaving section is located far from the open mesh weaving section end.

In addition, the number of braided wires in each strand of the open mesh weaving segment is greater than the number of braided wires in the dense mesh collecting segment.

In addition, the thrombus removal device further includes a conical head connected to the distal end of the collection part; the diameter of the proximal end of the collection part is greater than or equal to the diameter of the distal end of the cutting part.

It can be seen from the above technical solutions that the embodiments of the present application have at least the following advantages and beneficial effects:

In the thrombus removal device of the embodiment of the present application, the thrombus removal stent is released to the position of the thrombus, and the peripheral wall of the thrombus removal stent is expanded and attached to the inner wall of the blood vessel, and its proximal opening is opened and facing the thrombus. The thrombus can enter the collection part through the opening at the proximal end and the mesh on the wall of the cutting part, so that the thrombus can be completely stripped and collected out of the body; in addition, the length of the thrombus removal bracket can be adjusted through the inner tube and the push tube, so as to adjust the thrombus removal. The released state of the stent makes it suitable for thrombus clearance in a larger vessel size range.

Description of drawings

One or more embodiments are exemplified by the pictures in the corresponding drawings, and these exemplifications do not constitute a limitation to the embodiments. Elements with the same reference numerals in the drawings represent similar elements. Unless otherwise stated, the drawings in the drawings are not limited to scale.

FIG. 1 is a schematic structural view of a thrombus removal device provided in Embodiment 1 of the present application in an expanded state;

Figures 2a and 2b are a front view and a side view of the thrombus removal device shown in Figure 1, respectively;

Figures 3a to 3d are schematic structural views of the thrombectomy bracket of the thrombus removal device provided in the embodiment of the present application;

Fig. 4 is a schematic diagram of the connection structure of the collecting part and the cutting part of the thrombectomy bracket of the thrombus removal device provided by the embodiment of the present application;

[Corrected 25.02.2022 under Rule 91]
Figures 5a to 5d are structural schematic diagrams of the braided wire of the thrombectomy stent provided in the embodiment of the present application passing through the connecting hole;

Fig. 6a and Fig. 6b are schematic diagrams of the braided structure of the collecting part of the thrombectomy bracket of the thrombus removal device provided by the embodiment of the present application.

Detailed ways

In order to make the purpose, technical solutions and advantages of the present application clearer, some embodiments of the present application will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the present application, and are not intended to limit the present application.

Unless otherwise specified, the proximal end and the distal end mentioned in this application have the same meaning in terms of orientation, that is, in the state of use, the distal end is the end away from the operator, the proximal end is the end close to the operator, and the operator is at the proximal end. Control thrombectomy device.

Please refer to Fig. 1, Fig. 2a and Fig. 2b, a thrombus removal device provided by the embodiment of the present application can cooperate with other suitable delivery components to realize rapid removal of intravascular blocking materials such as plaque and thrombus. The thrombus removal device of the embodiment of the present application includes: a thrombectomy support 1 , an inner tube 3 and a pushing tube 4 . The inner tube 3 is installed in the thrombectomy bracket 1 and the push tube 4, the distal end of the inner tube 3 is connected with the distal end of the thrombectomy bracket 1, the inner tube 3 can move relative to the push tube 4 in the axial direction, and the proximal end of the thrombectomy bracket 1 is connected to the push tube 4. The push tube 4 is connected at the far end. The thrombectomy stent 1 is an expandable and contractible stent structure, and it includes: a collection part 11 and a cutting part 12 . The distal end of the collecting part 11 is in smooth contact with the proximal end of the cutting part 12. The collecting part 11 has a tubular structure with a closed distal end. The peripheral wall of the cutting part 12 has mesh holes and an opening at its proximal end.

As shown in Figure 1, when the thrombus retrieval stent 1 passes through the thrombus in the blood vessel, after the thrombus retrieval stent 1 is released at the distal end of the thrombus, the thrombus retrieval stent 1 can expand, and the inner tube 3 drives the thrombus retrieval stent 1 to extend axially. Or shortening can fine-tune the expansion form of the thrombectomy stent 1 to adapt to different vessel sizes. The peripheral wall of the expanded thrombectomy stent 1 can support and adhere to the inner wall of the blood vessel, and the proximal opening of the cutting portion 12 of the thrombus retrieval stent 1 is open and facing the thrombus. Withdraw the thrombus retrieval stent 1 to the proximal end, and the thrombus enters the collecting part 11 through the opening of the cutting part 12 and the mesh on the wall of the cutting part 12, so that the thrombus in the blood vessel can be stripped and collected, so as to be taken out of the body.

Referring to FIGS. 3 a to 3 d , the cutting part 12 includes: a plurality of first V-shaped rods, a plurality of second V-shaped rods, a plurality of connecting rods and a marking ring 13 . The first V-shaped bar is larger than the second V-shaped bar. Exemplarily, the shapes and dimensions of the plurality of first V-shaped bars are approximately the same, and the shapes and dimensions of the plurality of second V-shaped bars are approximately the same.

The plurality of first V-shaped rods are connected circumferentially and axially to form a cylindrical structure, and the plurality of first V-shaped rods form a plurality of first diamond-shaped meshes C3. The cylindrical structure of the cutting part 12 can support the inner wall of the blood vessel, so that the opening of the proximal end of the cutting part 12 can be opened, so that thrombus can enter the thrombus retrieval stent 1 through the opening. The plurality of first diamond-shaped meshes C3 on the peripheral wall of the cutting part 12 can also cut the thrombus when the thrombus retrieval stent is withdrawn, so that the thrombus can enter the interior of the thrombus retrieval stent 1 .

The plurality of first V-shaped rods includes a plurality of first V-shaped rods adjacent to the proximal end of the collection part 11 and the nodes are towards the proximal end. A V-shaped rod also includes a plurality of first V-shaped rods adjacent to the proximal end of the collection part 11 with nodes facing the distal end, referred to as first V-shaped rods 122 adjacent to the opening. The nodes are the intersections of the V-shaped bars. Wherein, a plurality of first distal openings are adjacent to the first V-shaped rod 121 and the proximal end of the collection part 11 to form a large triangular grid on the peripheral wall of the thrombus retrieval bracket 1 .

The nodes of the plurality of second V-shaped rods 123 are connected to the proximal end of the collection part 11 toward the distal end, and the two vertices of the opening ends of the plurality of second V-shaped rods 123 are respectively adjacent to the first V with the plurality of far openings. Shaped rod 121 is connected. Wherein, the second V-shaped bar 123 divides the peripheral wall of the cutting part between the far opening adjacent to the first V-shaped bar 121 and the proximal end of the collecting part 11 into two triangular meshes C4 and a second rhombic mesh C5, that is, the aforementioned large The triangular mesh is divided into two triangular meshes C4 and a second rhombic mesh C5, so that the distal end of the cutting part 12 forms a dense structure, which can provide better radial support force to better adhere to the inner wall of the blood vessel . At the same time, the triangular mesh C4 and the second diamond-shaped mesh C5 can also cut the thrombus, so that the thrombus can enter the thrombus retrieval bracket 1 easily.

The plurality of connecting rods include: two first arc-shaped connecting rods 125 and two second arc-shaped connecting rods 127 . A node at the proximal end of the cutting portion 12 is connected to the first V-shaped rod at the distal end and two nodes axially connected to the first V-shaped rod at the proximal end are connected to form a third V-shaped rod 124 , the distal ends of the two first arc-shaped connecting rods 125 respectively connect with the proximal ends of the third V-shaped rod 124 to form a first opening C2 . The proximal ends of the two first arc-shaped connecting rods 125 are converging and connected to the marking ring 13 . The marking ring 13 is fixedly sleeved on the distal end of the push tube 4 . Wherein, the proximal ends of the two first arc-shaped connecting rods 125 are connected to form straight rods and connected to the marking ring 13 . The first opening C2 is a relatively large oblique opening, which facilitates the passage of large thrombi into the thrombus retrieval bracket 1 , and the edge of the first opening C2 can cut the thrombus, facilitating the separation of the thrombus from the vessel wall.

A node at the proximal end of the cutting portion 12 is connected to the distal ends of the two second arc-shaped connecting rods 127 to form the second opening C1 . The proximal ends of the two second arc-shaped connecting rods 127 are converging and connected to the marking ring 13 . After the proximal ends of the two second arc-shaped rods 127 converge, they are straight rod-shaped and arranged at intervals, and are connected with the marking ring 13 . The first opening C1 is a small oblique opening, and the edge of the first opening C1 can cut the thrombus, which facilitates the separation of the thrombus from the blood vessel, and facilitates the entry of small thrombus into the thrombus retrieval support 1 through the first opening C1. The marking ring 13 can be made of X-ray-opaque metal, including but not limited to tantalum, platinum-iridium alloy, nickel-titanium alloy, and stainless steel. The marking ring 13 can be used to indicate the position of the thrombectomy stent in the blood vessel.

It should be noted that the cutting part 12 can be made by an integrated laser cutting process, for example, the cutting part 12 can be made of a nickel-titanium pipe through an integrated laser cutting and heat setting. The cutting part can be made of materials with shape memory ability, including but not limited to: shape memory alloy or shape memory polymer material.

Please refer to FIG. 4 , the collecting part 11 can be formed by interlacing braiding of multiple braiding wires. The collection part 11 can be braided from materials with shape memory properties, including but not limited to alloy wires or polymer wires, or co-braided from shape memory wires and polymer wires. The shape memory wire includes, but is not limited to, Nitinol wire. Materials of polymer filaments include, but are not limited to: polyester, polyethylene, ultra-high molecular weight polyethylene.

The distal end of the cutting part 12 is provided with several connecting holes 128 at intervals in the circumferential direction, and the collecting part 11 is connected to the cutting part 12 through the connecting holes 128 through the braided wire 131 at its proximal end. A plurality of V-shaped rods are evenly spaced around the distal end of the cutting portion, and the closed ends of the V-shaped rods form an arc-shaped connecting wall, and the connecting holes 128 are opened in the arc-shaped connecting wall. The connection hole 128 may be in a racetrack shape with an axial length smaller than a circumferential length. The racetrack-shaped connecting hole 128 is convenient for braiding wire to pass through. By arranging an arc-shaped connecting wall at the distal end of the cutting portion 12 and setting a connecting hole on the arc-shaped connecting wall, the connection between the collecting portion 11 and the cutting portion 12 can be made more flexible. Specifically, the plurality of connecting holes 128 can be respectively disposed on nodes of the plurality of second V-shaped rods 123 and the plurality of first V-shaped rods adjacent to the collecting portion 11 and whose nodes are facing the distal end.

Each connecting hole 128 can pass through a plurality of braiding wires, for example, two wires, and there can be various ways of winding the plurality of braiding wires. Please refer to FIG. 5 a , two braiding filaments 111 respectively pass through the connecting holes 128 and intersect with another braiding filament, and then merge into two strands of braiding filaments for forward and reverse braiding. Please refer to FIG. 5 b , one of the two braiding wires 111 passes through the connecting hole 128 and crosses, and then merges with the other braiding wire that does not cross after passing through the connecting hole 128 to form two strands of braiding wires for forward and reverse braiding. Please refer to Fig. 5c, after the two braided wires are passed through the same side of the connecting hole and passed out from the same side, they are directly merged into two strands of braided wires for forward and reverse weaving without intersecting. Please refer to 5d, after the two braiding wires respectively pass through and out from different sides of the connecting hole 128, they are directly merged into two strands of braiding wires without intersecting for forward and reverse braiding. After a plurality of braiding wires pass through a plurality of connecting holes and merge into two strands of braiding wires, the two strands of braiding wires respectively intersect with each other to form a tubular collecting part 11 in a forward and reverse helical structure towards the distal end. When the braiding filaments are cross-braided, the number of intersecting braiding filaments can be one or two strands. Correspondingly, the cross-braiding method can be one and one cross-braiding, please refer to Figure 6b; or two strands and two strands For cross braids, see Figure 6a; alternatively, one and two cross braids are also possible. Wherein, each strand of braided filaments may contain one or more braided filaments.

The collecting part 11 may include a dense mesh weaving section B and an open mesh weaving section A. Wherein, the dense mesh weaving section B may be located at the far end of the sparse mesh weaving section A, please refer to Fig. 3a. Alternatively, the dense mesh weaving section B and the open mesh weaving section A may be alternately distributed along the axial direction. The number of braided wires in each strand of the open mesh weaving segment is greater than the number of braided wires in the dense mesh collecting segment. For example, the number of braided wires in each strand of the open mesh weaving segment can be twice that of the braiding wires in the dense mesh collecting segment.

The thrombus removal device also includes a conical head 2 connected to the distal end of the collection part 11 , and a plurality of alloy wires at the distal end of the collection part 11 are converged and then connected to the distal end of the inner tube 3 and the proximal end of the conical head 2 . The distal end of the conical head 2 is a sharp point, which is convenient for pushing the thrombus removal device to the position of the thrombus in the blood vessel.

The diameter of the proximal end of the collection part 11 is greater than or equal to the diameter of the distal end of the cutting part 12, which not only facilitates the entry of thrombus into the collection part, but also can well support the inner wall of the blood vessel to prevent the thrombus from missing.

The collection part 11 may include a cylindrical collection section and a tapered collection section that are axially connected smoothly from the proximal end to the distal end. Optionally, the ratio of the axial length of the cylindrical collecting section, the tapered collecting section, and the cylindrical structure of the cutting part 12 to the maximum diameter of the thrombectomy support 1 is greater than 2, so that the thrombectomy support 1 is overall elongated. The tube body structure facilitates the removal of a large number of thrombus at one time.

Based on the above technical solutions, the embodiments of the present application at least have the following advantages and positive effects:

In the thrombus removal device of the embodiment of the present application, the thrombus removal stent is released to the position of the thrombus, and the peripheral wall of the thrombus removal stent is expanded and attached to the inner wall of the blood vessel, and its proximal opening is opened and facing the thrombus. The thrombus can enter the collection part through the opening at the proximal end and the mesh on the peripheral wall of the cutting part, so that the thrombus can be completely stripped and collected out of the body; in addition, the length of the thrombus retrieval bracket can be adjusted through the inner tube and the push tube, thereby adjusting the thrombus retrieval. The released state of the stent makes it suitable for thrombus clearance in a larger vessel size range.

Those of ordinary skill in the art can understand that the above-mentioned embodiments are specific embodiments for realizing the present application, and in practical applications, various changes can be made to it in form and details without departing from the spirit and spirit of the present application. scope.

Claims

A thrombus removal device, comprising: a thrombectomy bracket, an inner tube, and a pushing tube;

The inner tube is passed through the thrombus-retrieving bracket and the pushing tube, the distal end of the inner tube is connected to the distal end of the thrombus-retrieving bracket, and the inner tube can move axially relative to the pushing tube; The proximal end of the thrombus retrieval bracket is connected to the distal end of the push tube;

The thrombectomy stent is an expandable and contractible stent structure, and it includes: a collecting portion and a cutting portion; the distal end of the collecting portion is smoothly connected to the proximal end of the cutting portion, and the collecting portion is closed at the distal end In the tubular structure, the peripheral wall of the cutting part has a mesh and its proximal end has an opening.
The thrombus removal device according to claim 1, wherein the collecting part is formed by interlacing braiding wires, and the cutting part is made by an integrated laser cutting process.
The thrombus removal device according to claim 2, wherein both the collecting part and the cutting part are made of the following materials: shape memory alloy and/or shape memory polymer material.
The thrombus removal device according to claim 2, wherein the distal end of the cutting part is provided with several connecting holes at intervals in the circumferential direction, and the braided wire at the proximal end of the collecting part passes through the connecting holes and the cutting part. department connected.
The thrombectomy device according to claim 4, wherein a plurality of V-shaped rods are evenly spaced around the distal end of the cutting part; the closed ends of the V-shaped rods form arc-shaped connecting walls, and the connecting holes open on the arc connecting wall.
The thrombectomy device according to claim 5, wherein the connecting hole is in a racetrack shape with an axial length smaller than a circumferential length.
The thrombectomy device according to claim 2, wherein the cutting portion comprises a plurality of first V-shaped rods and a plurality of second V-shaped rods; the plurality of second V-shaped rods are smaller than the plurality of first V-shaped rods a V-shaped bar;

The plurality of first V-shaped rods are connected circumferentially and axially to form a cylindrical structure, and the plurality of first V-shaped rods form a plurality of first diamond-shaped meshes;

The plurality of first V-shaped rods includes a plurality of distal openings adjacent to the proximal end of the collection portion with nodes facing the proximal end adjoining the first V-shaped rods, and the nodes of the plurality of second V-shaped rods face the distal end and are respectively connected to the proximal ends of the collecting parts, and the two vertices of the opening ends of the plurality of second V-shaped rods are respectively connected to the first V-shaped rods adjacent to the far openings of the plurality of said second V-shaped rods; The V-shaped bar divides the peripheral wall of the cutting part between the distal opening adjoining the first V-shaped bar and the proximal end of the collecting part into two triangular meshes and a second diamond-shaped mesh.
The thrombus removal device according to claim 7, wherein the distal end of the cutting part is provided with several connecting holes at intervals in the circumferential direction, and the braided wire at the proximal end of the collecting part passes through the connecting holes and the cutting part. Department connected;

The plurality of connection holes are respectively arranged on the nodes of the plurality of second V-shaped rods and the plurality of first V-shaped rods adjacent to the collecting part and the nodes are facing the distal end.
The thrombectomy device according to claim 5, wherein the cutting part further comprises two first arc-shaped connecting rods and two second arc-shaped connecting rods;

A node at the proximal end of the cutting portion is connected to the first V-shaped rod at the distal end and two nodes axially connected to the first V-shaped rod at the proximal end are connected to form a third V-shaped rod. Rods, the distal ends of the two first arc-shaped connecting rods respectively connect with the proximal ends of the third V-shaped rods to form a first opening;

A node at the proximal end of the cutting portion is connected to the distal ends of the two second arc-shaped connecting rods respectively to form a second opening.
The thrombus removal device according to claim 9, wherein the thrombectomy bracket further comprises a marking ring, and the proximal ends of the two first arc-shaped connecting rods and the two second arc-shaped connecting rods are convergingly connected to the A marking ring, the marking ring is fixedly sleeved on the distal end of the push tube.
The thrombus removal device according to claim 2, wherein the collection part comprises a dense mesh weaving section and an open mesh weaving section; A mesh weave segment is located distal to the open mesh weave segment.
The thrombus removal device according to claim 11, wherein the number of braided wires per strand of the open mesh braided section is greater than the number of braided wires of the dense mesh collection section.
The thrombus removal device according to claim 1, wherein the thrombus removal device further comprises a conical head connected to the distal end of the collection part; the diameter of the proximal end of the collection part is greater than or equal to that of the distal end of the cutting part diameter of.