WO2021244332A1

WO2021244332A1 - Thrombectomy stent and thrombectomy system

Info

Publication number: WO2021244332A1
Application number: PCT/CN2021/095279
Authority: WO
Inventors: 王永胜; 于鹏; 高国庆; 程舒宇
Original assignee: 杭州德诺脑神经医疗科技有限公司
Priority date: 2020-05-30
Filing date: 2021-05-21
Publication date: 2021-12-09

Abstract

A thrombectomy stent (100, 100h, 100a, 100b, 100d), comprising a stent body (101, 101h, 101a, 101b, 101d), and a protection umbrella (6, 6h) arranged at a distal end of the stent body (101, 101h, 101a, 101b, 101d), wherein a first opening end (103, 301a, 301b, 301d) is formed at the distal end of the stent body (101, 101h, 101a, 101b, 101d); an umbrella opening end (601, 601h) directly opposite the first opening end (103, 301a, 301b, 301d) is formed at a proximal end of the protective umbrella (6, 6h); a sealing end (603) directly opposite the umbrella opening end (601, 601h) is formed at a distal end of the protective umbrella (6, 6h); and the umbrella opening end (601, 601h) is connected to the first opening end (103, 301a, 301b, 301d), such that a continuous channel (1010、1010a、1010b、1010d) is formed inside the thrombectomy stent (100, 100h, 100a, 100b, 100d).

Description

Bolt-removing bracket and bolt-removing system

This application requires the priority of the Chinese patent application filed with the Chinese Patent Office on May 30, 2020, the application number is CN 202010482444.9, and the invention title is "Stent and Thromb Removal System" and it is filed in China on May 30, 2020 The patent office, the application number is CN 202020965303.8, and the title of the invention is the priority of the Chinese patent application "Stent and Bolt Removal System", the entire content of which is incorporated into this application by reference.

Technical field

The invention relates to the technical field of medical devices, in particular to a thrombus removal stent and a thrombus removal system.

Background technique

Thrombus is a small piece of blood that forms on the surface of the exfoliated or repaired part of the blood vessel of the cardiovascular system. Thrombosis spreads throughout the cardiovascular system and spreads to tissues and organs throughout the body. It is not limited to myocardial infarction, deep vein thrombosis or cerebrovascular thrombosis. Thrombosis can occur in blood vessels in any part of the body. Intracranial thrombosis is a special clinical type of cerebrovascular disease. It is easy to cause cerebral embolism. It has the characteristics of high morbidity, disability, mortality and recurrence. It is fatal and disabling for middle-aged and elderly people. The main disease.

The recanalization of blood vessels is the key to the treatment of acute ischemic stroke. At present, the conventional methods for the treatment of ischemic stroke include two categories: drug thrombolysis or mechanical thrombectomy.

Drug thrombolysis is a catheter injecting a thrombolytic agent into the appendages of the lesion in the blood vessel that the lesion refers to, and a high concentration of thrombolytic agent is formed in the local area of the lesion, thereby accelerating the speed of thrombolysis and increasing the chance of vascular recanalization. According to the findings of the National Institute of Neurological Diseases and Stroke, intravenous thrombolysis should be performed within 3 hours of onset, and the arterial thrombolysis time window is within 6 hours. Therefore, drug thrombolytic therapy is only suitable for smaller blood clots. When the volume of the thrombus is too large, a very large dose is required to dissolve the large blood clot, and it is easy to cause various complications, and the risk is high.

In order to solve the above-mentioned drug thrombolytic problem, mechanical methods are used to eliminate thrombosis. Mechanical thrombectomy includes the following methods: thrombectomy, laser thrombectomy, thrombectomy with catcher, thrombectomy with thrombectomy net. The thrombectomy is more thorough in removing the thrombus, but it damages the blood vessel wall too much, which can easily cause various concurrent inflammations. The operation of laser thrombus breaking is very difficult. If the laser energy is too low, it will be ineffective. If the energy is too high, the blood vessels will be damaged, and it is also easy to cause various complications. The operation of the catcher to remove the thrombus is simple, and it does little damage to the blood vessel wall, but it often fails to catch the blood clot. The operation of the thrombus-trapping net to remove the thrombus is simple, but because the thrombus-trapping net is large in size, it cannot be used in intracranial blood vessels. To sum up, the existing mechanical thrombectomy method fails to effectively capture the thrombus falling from the thrombus retrieval stent, which is likely to cause re-embolization of the blood vessel and complications caused by thrombectomy therapy.

Summary of the invention

In view of this, it is necessary for the present invention to provide a bolt-removing support and a bolt-removing system to solve the above-mentioned technical problems.

In the first aspect, an embodiment of the present invention provides a plug-removing stent, including a stent body and a protective umbrella provided at the distal end of the stent body. The distal end of the stent body forms a first open end, and the proximal end of the protective umbrella is The end forms an umbrella end that is directly opposite to the first open end, the distal end of the protective umbrella forms a closed end that is directly opposite to the umbrella end, and the umbrella end is connected to the first open end to make A continuous channel is formed inside the bolt-removing bracket.

In a second aspect, an embodiment of the present invention provides a thrombus removal system, including a push rod, a microcatheter, and the above-mentioned thrombus removal stent. The thrombus removal stent includes a stent body and a protective umbrella provided at the distal end of the stent body , The push rod is connected to the proximal end of the stent body, the push rod, the stent body and the protective umbrella are crimped into the microcatheter, the stent body and the protective umbrella can pass through the Pushing and pulling of the pushing rod moves inside and outside the micro catheter. When the pushing rod moves toward the proximal end of the micro catheter, the stent body and the protective umbrella are recovered into the micro catheter; when When the push rod moves in a direction away from the proximal end of the micro catheter, the stent body and the protective umbrella are pushed out of the micro catheter.

Compared with the prior art, the thrombus retrieval stent and thrombus retrieval system provided by the embodiments of the present invention are based on the provision of a protective umbrella at the distal end of the thrombus retrieval stent, thereby effectively preventing thrombus detached from the stent body from escaping. In addition, the distal end of the stent body forms a first open end, the proximal end of the protective umbrella forms an umbrella end opposite to the first open end, the distal end of the protective umbrella forms a sealed end opposite to the umbrella end, and the umbrella end is connected to the first opening. The ends are connected, so that a continuous channel is formed inside the bolt-removing bracket. In this way, the thrombus detached from the stent body completely enters the protective umbrella without being blocked, so that the protective umbrella can effectively recover the thrombus detached from the stent body, thereby avoiding the problem of blood vessel re-embolism caused by the thrombus detaching from the stent body, and preventing the removal of the thrombus. Complications caused by embolization treatment, thereby increasing the recanalization rate of blood vessels. In addition, because the mouth end of the umbrella is connected to the first open end, that is, the protective umbrella is close to the distal end of the stent body, thereby preventing thrombus from escaping, and the protective umbrella and the stent body are released synchronously, so the protective umbrella can rely on the radial support force of the stent body The protective umbrella is quickly opened until the protective umbrella is unfolded to a predetermined state to accommodate the thrombus falling off the stent body.

Description of the drawings

In order to explain the embodiments of the present invention or the technical solutions in the prior art more clearly, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only These are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative labor.

Fig. 1 is a schematic diagram of the structure of the bolt removal bracket provided by the first embodiment of the present invention.

Fig. 2 is an enlarged view of a part of the structure of the bolt removal bracket in Fig. 1.

FIG. 3 is a schematic diagram of the bolt removal process of the bolt removal bracket in FIG. 1.

Fig. 4 is a schematic structural diagram of a bolt removal bracket provided by a second embodiment of the present invention.

FIG. 5 is a schematic diagram of the structure of the stent body of the bolt removal stent in FIG. 4.

FIG. 6 is a schematic diagram of the structure of the protective umbrella of the bolt-removing bracket in FIG. 4.

Fig. 7 is a schematic diagram of the structure of the mesh body of the protective umbrella of the bolt-removing bracket in Fig. 6.

Fig. 8 is a bottom view of the net body of the protective umbrella of the bolt-removing bracket in Fig. 7.

Fig. 9 is a schematic structural diagram of a bolt removal bracket provided by the third embodiment of the present invention.

Fig. 10 is an enlarged view of a part of the structure of the bolt removal bracket in Fig. 9.

FIG. 11 is a schematic diagram of the bolt removal process of the bolt removal bracket in FIG. 9.

Fig. 12 is a cross-sectional view of the bolt removal bracket in Fig. 11 along the XII-XII direction.

Fig. 13 is a schematic structural diagram showing the whole structure of the stent body of the bolt removal stent in Fig. 9 in the semi-free state.

Fig. 14 is a schematic diagram of the structure of the bolt removal bracket provided by the fourth embodiment of the present invention.

Fig. 15 is a schematic structural view of the bolt removal bracket in Fig. 14 from another angle.

Fig. 16 is a schematic diagram of the structure of the bolt removal bracket provided by the fifth embodiment of the present invention.

Fig. 17 is a schematic structural view of the bolt removal bracket in Fig. 16 from another angle.

Fig. 18 is a schematic structural diagram of a bolt removal system provided by an embodiment of the present invention.

detailed description

The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of the present invention.

It should be noted that in the field of interventional medicine, the end of the instrument that is relatively close to the operator is usually called the proximal end, and the end of the instrument that is relatively far away from the operator is called the distal end. Specifically, the distal end refers to the end of the instrument that can be freely inserted into the animal or human body. The near end refers to the end used for user or machine operation or the end used to connect to other devices.

It can be understood that the terms in the specification and claims of the present invention and the above-mentioned drawings are only for describing specific embodiments, and are not intended to limit the present invention. The terms "first", "second", "third", "fourth", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific sequence. Unless the context clearly states otherwise, the singular forms "a" and "the" are also intended to include the plural forms. The term "including" and any variations of them are intended to cover non-exclusive inclusion. In addition, the present invention can be implemented in a variety of different forms, and is not limited to the embodiment described in this embodiment. The purpose of providing the following specific embodiments is to facilitate a clearer and thorough understanding of the disclosure of the present invention, wherein the words indicating directions such as up, down, left, and right are only for the position of the structure shown in the corresponding drawings. The term "axial" refers to the direction in which the thrombus removal stent of the present invention is advanced, that is, the longitudinal axis of the thrombus removal stent and also coincides with the longitudinal axis of the blood vessel. The term "closed" does not mean that a certain element structure is a completely sealed object, its structure only represents a characteristic of the element structure, that is, the mesh body can form a storage space for thrombus, and the thrombus is not easy to escape from the place. The sealing structure of the mesh body is described.

The following descriptions of the specification are preferred embodiments for implementing the present invention. However, the foregoing description is for the purpose of explaining the general principles of the present invention and is not intended to limit the scope of the present invention. The protection scope of the present invention shall be subject to those defined by the appended claims.

Please refer to FIG. 1. FIG. 1 is a schematic structural diagram of a bolt removing bracket 100 provided by a first embodiment of the present invention, and FIG. 2 is an enlarged view of a partial structure of the bolt removing bracket 100. The bolt removal stent 100 includes a stent body 101 and a protective umbrella 6 arranged at the distal end of the stent body 101. The distal end of the stent body 101 forms a first open end 103, and the proximal end of the protective umbrella 6 forms an umbrella directly opposite to the first open end 103. In the mouth end 601, the distal end of the protective umbrella 6 forms a sealing end 603 directly opposite to the umbrella mouth end 601, and the umbrella mouth end 601 is connected with the first open end 103 so that a continuous channel 1010 is formed inside the bolt removal bracket 100.

Since the distal end of the thrombus removal stent 100 is provided with a protective umbrella 6, thereby effectively preventing the thrombus falling from the thrombus removal stent 100 from escaping. In addition, the distal end of the stent body 101 forms a first open end 103, the proximal end of the protective umbrella 6 forms an umbrella mouth end 601 directly opposite to the first open end 103, and the distal end of the protective umbrella 6 forms a sealing mouth directly opposite to the umbrella mouth end 601 The end 603, the umbrella end 601 and the first open end 103 are connected, so that a continuous channel 1010 is formed inside the bolt removal bracket 100. In this way, the thrombus detached from the thrombus removal stent 100 completely enters the protective umbrella 6 without being blocked, so that the protective umbrella 6 can effectively recover the thrombus detached from the thrombus removal stent 100, thereby avoiding blood vessels caused by the thrombus falling from the thrombus removal stent 100 Re-embolization problems and prevent complications caused by thrombectomy treatment, thereby increasing the recanalization rate of blood vessels. In addition, because the umbrella mouth end 601 is connected with the first open end 103, that is, the protective umbrella 6 is close to the distal end of the stent body 101, thereby preventing thrombus from escaping, and the thrombus removal stent 100 and the protective umbrella 6 can be released synchronously, thereby protecting the umbrella 6 The protective umbrella 6 can be quickly opened by the radial support force of the stent body 101 until the protective umbrella 6 is expanded to a predetermined state, so as to recover the thrombus that has fallen off the stent body 101.

Wherein, the stent body 101 and the protective umbrella 6 can be formed by laser cutting a plate-shaped nickel-titanium alloy to form a tubular or cage-like structure with a hollow structure, and then be crimped and heat-treated to shape. In another embodiment, the stent body 101 and the protective umbrella 6 can also be formed into a tubular or cage-like structure with a hollow structure by weaving a wire-like nickel-titanium alloy. In some other embodiments, the bracket body 101 and the protective umbrella 6 can also be processed by using elastic plastic materials.

In this embodiment, the stent body 101 is laser-engraved from a pipe network material with a shape memory effect; the protective umbrella 6 is woven from a wire-like material with a shape memory effect. Among them, the pipe network material or filamentary material includes, but is not limited to, metal materials, elastic polymer materials or elastic plastic materials. In addition, the stent body 101 and the protective umbrella 6 can be self-expanded to form a tubular and/or cage-like structure. The metal material is, for example, but not limited to nickel-titanium alloy or cobalt-based alloy. The stent body 101 made of pipe network material has certain radial and axial supporting force, so as to ensure that the stent body 101 has good adhesion to the wall. Therefore, the thrombus can be prevented from entering the thrombus in the fully released state of the thrombus removal stent 100 In the gap between the stent 100 and the blood vessel wall. The protective umbrella 6 woven from a wire-like material has a mesh unit with a small mesh area, so that a relatively small thrombus can be captured, so as to improve the efficiency of capturing the thrombus. In addition, the protective umbrella 6 is relatively soft, thereby reducing damage to the blood vessel wall.

In this embodiment, the peripheral edge of the first open end 103 is provided with a mounting structure 104, and the peripheral edge of the umbrella mouth end 601 is provided with a connecting structure 602 matingly connected with the mounting structure. The connection method of the mounting structure 104 and the connection structure 602 is, for example, but not limited to bonding, welding, crimping, or snap connection. The mounting structure 104 and the connecting structure 602 are directly connected together, which not only facilitates processing and molding, but also simplifies the overall structure of the bolt-removing bracket 100.

In some embodiments, the bolt removal bracket 100 further includes a connecting member 8. The mounting structure 104 is connected to the connecting structure 602 through the connecting member 8 so that the umbrella mouth end 601 and the first open end 103 are connected. The mounting structure 104 and the connecting structure 602 are connected together by the connecting piece 8, which improves the compactness and stability of the connection between the support body 101 and the protective umbrella 6.

The first open end 103 forms a first bending portion 105 that is continuously bent, the mounting structure 104 is disposed on the first bending portion 105, the umbrella mouth end 601 forms a second bending portion 604 that is continuously bent, and the connection structure 602 is disposed on the second bending part 604. Wherein, the first bending portion 105 and the second bending portion 604 are both wavy or zigzag-shaped. In this way, the first open end 103 and the umbrella mouth end 601 can provide more connection points to improve the stability and reliability of the connection between the bracket body 101 and the protective umbrella 6, and to ensure that the bracket body 101 and the protective umbrella 6 can be released simultaneously, so that The protective umbrella 6 quickly opens the protective umbrella 6 with the help of the radial support force of the stent body 101, thereby effectively capturing the thrombus in the blood vessel.

Specifically, the first open end 103 is formed by enclosing a plurality of first mesh openings 106, the distal end of each first mesh opening 106 is configured as a first bending structure 1061, and the plurality of first bending structures 1061 are connected to each other to form a first bending structure 1061. A bending part 105. The umbrella mouth end 601 is formed by a plurality of first grid units 606, the proximal end of each first grid unit 606 is configured as a second bending structure 6061, and the multiple second bending structures 6061 are connected to each other to form a second bending Fold 604. In this embodiment, the first bending structure 1061 and the second bending structure 6061 are V-shaped. Both the first bending portion 105 and the second bending portion 604 are in a zigzag shape.

Wherein, the number of the plurality of first network ports 106 is less than the number of the plurality of first grid units 606, and the area of each first network port 106 is greater than the area of each first grid unit 606. In this way, the protective umbrella 6 can recover a relatively small thrombus, so as to further improve the thrombus capture efficiency of the thrombus removal stent 100.

Specifically, the shapes of the plurality of first mesh ports 106 and the plurality of first mesh units 606 include, but are not limited to, one or more of a circle, an ellipse, a triangle, a diamond, a trapezoid, and a hexagon. In this embodiment, the shapes of the plurality of first network ports 106 and the plurality of first grid units 606 are all rhombuses.

The mounting structure 104 is formed by enclosing a plurality of connecting pieces 107 with connecting holes 1071, and the plurality of connecting pieces 107 are respectively arranged on the plurality of first bending structures 1061. The connecting structure 602 is formed by enclosing a plurality of connecting buckles 605, each connecting buckle 605 is arranged on the corresponding second bending structure 6061, the connecting piece 8 is configured as a connecting ring, and the connecting ring passes through the connecting hole 1071 of each connecting piece 107 And a plurality of connecting buckles 605 to connect the protective umbrella 6 and the bracket body 101. The connecting ring is made of a material with a shape memory effect. In this way, the connecting ring can quickly open the protective umbrella 6 with the help of the radial support force of the stent body 101, and the design of the connecting ring can prevent the umbrella mouth end 601 of the protective umbrella 6 from collapsing and enhance the adhesion of the protective umbrella 6 to the blood vessel wall, thereby Improve the efficiency of capturing thrombus.

The symmetry axis of each first mesh port 106 parallel to the central axis L of the bolt removal bracket 100 roughly coincides with the symmetry axis of the corresponding first grid unit 606 parallel to the central axis L of the bolt removal bracket 100 so as to connect 605 pairs of buckles. The quasi-connection hole 1071 is used to facilitate assembly.

In some embodiments, the number of connecting buckles 605 is equal to the number of connecting holes 1071. Each connecting buckle 605 is correspondingly disposed on each second bending structure 6061. In this way, it is possible to avoid the collapse of the umbrella mouth end 601 of the protective umbrella 6 causing a gap between the protective umbrella 6 and the blood vessel wall, thereby ensuring the radial support force of the umbrella mouth end 601 and enhancing the adhesion of the protective umbrella 6 to the blood vessel wall. This improves the efficiency of capturing thrombus.

In some other embodiments, the number of connecting buckles 605 is more than the number of connecting holes 1071. Each connecting buckle 605 is arranged at a position corresponding to the connecting hole 1071 of the second bending structure 6061, thereby facilitating the assembly of the protective umbrella 6 and the bracket body 101.

The protective umbrella 6 includes a net body 63 formed by interlacing a plurality of ribs 61, each rib 61 is structured in a petal structure and distributed in a radial shape, and the proximal end of each rib 61 protrudes outward relative to the net body 63. The second bending structure 6061.

In this embodiment, the connecting buckle 605 and the second bending structure 6061 are integrally formed. The middle of each rib 61 crosses to form a corresponding connecting buckle 605, thereby improving the stability and reliability of the connecting buckle 605, and the processing method is simple.

In some other embodiments, the plurality of connecting buckles 605 may also be formed on the corresponding second bending structure 6061 by mechanical fixing. The mechanical fixing method is, for example, but not limited to bonding, welding, riveting, crimping, or wire-like material winding.

In this embodiment, the net body 63 includes a cylindrical extension portion 62 and a conical recovery portion 64. The extension portion 62 is provided between the bracket body 101 and the recovery portion 64, and a plurality of connecting buckles 605 are provided on the extension portion 62. Near end. The outer diameter of the extension 62 is approximately equal to the outer diameter of the stent body 101. In this way, by providing an extension 62 at the proximal end of the protective umbrella 6, the overall area of the protective umbrella 6 is increased, thereby preventing the thrombus in the thrombus removal stent 100 from escaping, thereby improving the thrombus capture performance of the thrombus removal stent 100. In this way, the thrombectomy stent 100 can remove the thrombus cleanly, prevent vasospasm, and can quickly restore the blood flow velocity. In addition, the proximal end of the protective umbrella 6 and the distal end of the stent body 101 are smoothly connected to ensure the flexibility of the thrombus removal stent 100, thereby reducing damage to the blood vessel wall, and the thrombus removal stent 100 and the protective umbrella 6 can be released simultaneously.

Specifically, the extension 62 is formed by a combination of a plurality of first grid units 606 and a plurality of second grid units 621. The recovery part 64 is formed by enclosing a plurality of third grid units 641, the area of the plurality of second grid units 621 is the same, and the area of the plurality of third grid units 641 gradually increases from the distal end to the proximal end. The area of the second grid unit 621 is larger than the area of the third grid unit 641, smaller than the area of the first network port 106, and equal to the area of the first grid unit 606. In this way, before the thrombus removal stent 100 enters the fully released state, the protective umbrella 6 is not expanded to the predetermined state. At this time, a smaller volume of thrombus can still enter the extension 62 from the first mesh unit 606 or the second mesh unit 621 , And then recovered by the recovery part 64 to further improve the efficiency of capturing thrombus. In addition, the mesh design of the mesh body 63 is gradually densified from the proximal end to the distal end to prevent the thrombus that enters the mesh body 63 from escaping, thereby recovering the thrombus shed from the thrombus removal stent 100 to increase the blood vessel recanalization rate.

The central axis of the embolization stent 100 is collinear with the central axis of the stent body 101 and the central axis of the protective umbrella 6, thus improving the stability of the embolism removing stent 100 and ensuring the smooth movement of the stent body 101 and the protective umbrella 6 in the blood vessel .

Wherein, the maximum outer diameter of the protective umbrella 6 is greater than or equal to the maximum outer diameter of the thrombus removal stent 101, so that the protective umbrella 6 can capture more thrombus shed from the thrombus removal stent 100. The orthographic projection of the umbrella mouth end 6 on the first open end 103 along the axial direction coincides with the first open end 103. In this way, the adhesion of the protective umbrella 6 to the blood vessel wall is enhanced to improve the efficiency of capturing thrombus.

In this embodiment, the protective umbrella 6 further includes a protective sleeve 65. The protective sleeve 65 is fixedly sleeved on the distal end of the umbrella rib 61 to wrap and tighten the distal end of the umbrella rib 61. In this way, contact between the distal end of the rib 61 and the blood vessel wall is avoided, thereby reducing damage to the blood vessel wall, and ensuring that the thrombus falling off or overflowing from the thrombus removal stent 100 is always contained in the protective umbrella 6.

In some embodiments, the protective sleeve 65 of the protective umbrella 6 may be configured as a development positioning element. The imaging positioning element is fixedly sleeved on the distal end of the umbrella rib 61 to wrap and tighten the distal end of the umbrella rib 61. The developing positioning element is, for example, but not limited to, a developing ring or a developing wire. In some embodiments, the developing wire is spirally wound at the distal end of the protective umbrella 6. In some other embodiments, the imaging ring is sleeved on the distal end of the protective umbrella 6. The imaging positioning element is fixed on the distal end of the rib 61 to serve as the distal end mark of the entire thrombus removal stent 100, so as to more accurately locate the position of the thrombus. The fixing method of the developing positioning element is, for example, but not limited to welding, crimping, hot melting or pressure riveting, and other common technical means in the art to be fixedly connected together. In some other embodiments, the protective umbrella may include both the imaging positioning element and the protective sleeve disposed at the distal end of the protective umbrella.

In this embodiment, the stent body 101 is configured as a tubular structure, a cage structure, or a combined structure of a tubular structure and a cage structure. The stent body 101 includes a first stent body 10 and a second stent body 30 disposed at the distal end of the first stent body 10. The first stent body 10 and the second stent body 30 are smoothly transitioned and connected, and the second stent body 30 includes the first stent body 10 and the second stent body 30. The capture section 31, the second capture section 33, and the transition section 35. The first catching section 31 and the second catching section 33 are alternately connected, and the first catching section 31 and the second catching section 33 are connected together by a transition section 35.

Wherein, the first catching section 31 and the second catching section 33 are both constructed as equal pipe diameter sections, and the pipe diameter of the first catching section 31 is equal to the pipe diameter of the second catching section 33. Among them, the first catch section 31 is formed by a plurality of first closed loop units 311, and the second catch section 33 is formed by a plurality of second closed loop units 331. The transition section 35 is formed by enclosing a plurality of supporting rods 350. The area and shape of the first closed-loop unit 311 are the same as those of the second closed-loop unit 331. The shapes of the first closed-loop unit 311 and the second closed-loop unit 331 include one or more of a rhombus, a circle, an ellipse, a triangle, a trapezoid, and a hexagon. In this embodiment, the area and shape of the first network port 106 and the area and shape of the second closed loop unit 331 are the same. That is, the first open end 103 is configured as the second capture section 33.

Specifically, the plurality of support rods 350 include a plurality of first support rods 351 and a plurality of second support rods 352. The plurality of first support rods 351 and the plurality of second support rods 352 are arranged at intervals along the radial direction of the second bolt removal bracket 30. A plurality of first support rods 351 are arranged at the proximal end of the first catching section 31, and a plurality of second support rods 352 are arranged at the distal end of the second catching section 33 at intervals.

Both the first closed-loop unit 311 and the second closed-loop unit 331 include

proximal connection points

3111 and 3311 and middle connection points 3112 and 3312. The distal end of the first support rod 351 is connected to the proximal connection point 3312 of the second closed loop unit 331, the proximal end of the first support rod 351 is connected to the middle connection point 3112 of the first closed loop unit 311; the distal end of the second support rod 352 is connected The proximal end of the first closed loop unit 31 is connected to the point 3111, and the proximal end of the second support rod 352 is connected to the middle connection point 3313 of the second closed loop unit 331.

In this embodiment, the first closed-loop unit 311 and the second closed-loop unit 331 are both diamond-shaped. The first catching section 31 is surrounded by four first closed-loop units 311 to form a tubular structure. Each first closed loop unit 311 has two middle connection points 3112. Two adjacent first closed-loop units 311 are connected together by a middle connection point 3112. The second capture section 33 is enclosed by three second closed loop units 331 to form a tubular structure. Each second closed loop unit 331 has two middle connection points 3312. Two adjacent second closed-loop units 331 are connected together by a middle connection point 3312. The plurality of first closed-loop units 311 and the plurality of second closed-loop units 331 are staggered, so that the second closed-loop unit 331 is arranged between two adjacent first closed-loop units 311, so that the bolt removal bracket 100 is more easily compressed and more capable It is suitable for small blood vessels and is easy to introduce into the micro catheter.

The distal end of the first closed loop unit 311 forms a first capture unit 3114, and the distal end of the second closed loop unit 331 forms a second capture unit 3314. The first catching unit 3114 and the first supporting rod 351 are alternately arranged and connected to each other, and the second catching unit 3314 and the second supporting rod 352 are alternately arranged and connected to each other, which not only ensures the flexibility of the bolt removal bracket 100, but also makes the removal The thrombus stent 100 has a certain supporting force in the radial and axial directions, and the thrombus capture efficiency of the thrombus removal stent 100 is improved.

Wherein, the first closed-loop unit 311 and the second closed-loop unit 331 both include

free ends

3113 and 3313 that are directly opposite to the

proximal connection points

3111 and 3311. The two middle connection points 3112 of the first closed loop unit 311 are connected to the free end 3113 to form the first catching unit 3114. The two middle connection points 3312 of the second closed loop unit 331 are connected to the free end 3313 to form a second catching unit 3314. The first capturing unit 3114 and the second capturing unit 3314 may have a V-shaped, W-shaped, zigzag, or U-shaped structure to improve the efficiency of capturing thrombus. In this embodiment, the first catching unit 3114 and the second catching unit 3314 are both constructed in a V-shaped structure.

The first catching unit 3114 and the second catching unit 3314 are alternately arranged along the circumferential direction of the second bracket body 30, that is, the second catching unit 3314 is arranged between two adjacent first catching units 3114 to be The thrombus stent 100 is radially covered with capture units, thereby improving the anchoring effect of thrombus. The first catching unit 3114 and the second catching unit 3314 and the bracket body 101 respectively form a first receiving space 3115 and a second receiving space 3315 that correspond to each other. Both the first catching unit 3114 and the second catching unit 3314 extend outward or inward with respect to the bracket body 101. The bending directions of the first catching unit 3114 and the second catching unit 3314 are opposite to the bending directions of the first support rod 351 and the second support rod 352. In this way, the space of the first accommodating space 3115 and the second accommodating space 3315 is increased, which can provide more accommodating space for the thrombus, so that the thrombus can enter the inner cavity of the thrombus removal stent 100, thereby further improving the resistance of the thrombus removal stent 100 to thrombus. The capture efficiency. When the thrombus removal stent 100 is in a normal working state (that is, in an expanded state), the first capturing unit 3114 and the second capturing unit 3314 are inserted into the thrombus, or the thrombus is clamped in the first receiving space 3115 and the second receiving space 3315, thereby improving the anchoring of thrombus by the thrombus removal stent 100. Since the first catching unit 3114 and the second catching unit 3314 are evenly distributed in the circumferential direction of the stent body 101, the flexibility of the thrombus removal stent 100 is enhanced, and the efficiency of catching thrombus is also improved.

The first catching unit 3114 and the second catching unit 3314 can move in a direction perpendicular to the central axis L of the bolt removal bracket 100. In this way, when the thrombus removal stent 100 moves in the blood vessel, the first capture unit 3114 and the second capture unit 3314 do not directly contact the blood vessel wall, thereby avoiding damage to the blood vessel wall tissue.

Further, the distal end of the first capture unit 3114 and the distal end of the second capture unit 3314 are both provided with arc-shaped chamfers to further avoid the distal end of the first capture unit 3114 and the second capture unit 3114. 3314 damages the blood vessel wall.

In this embodiment, the first bracket body 10 is formed by a plurality of closed loop units 11, and the area and shape of the closed loop unit 11 are the same as those of the first closed loop unit 311 and the second closed loop unit 331. In some other embodiments, the first stent body 10 may also include closed-loop units of one, two or more shapes at the same time.

The proximal end of the stent body 101 is configured as an oblique cone cylindrical structure. A plurality of closed loop units 11 are connected to each other to form an oblique cone cylindrical structure. The proximal end of the stent body 101 forms an entrance 15 with a slope. The shape of the inlet 15 is tapered, such as a drop shape. In this embodiment, the shape of the inlet 15 is a fusiform. In this way, based on the gradient design of the entrance 15 of the stent body 101, not only can the withdrawal force of the withdrawal bolt removal stent 100 be effectively prevented from being transmitted to the entire circumference of the bolt removal stent 100, but also the pipe diameter of the stent body 101 is prevented from being withdrawn. The embolic stent 100 becomes smaller during the process, so as to ensure that the thrombus is not easy to fall off during the embolization stent 100 is withdrawn.

In some other embodiments, the proximal end of the first stent body can also be configured as a funnel structure, and the second stent body is configured as a straight tube structure, so that the thrombus can be avoided during the withdrawal of the thrombus removal stent in the direction close to its proximal end. Of falling off. Wherein, the tube diameter of the first stent body gradually increases from the proximal end to the distal direction, thereby preventing the proximal end of the first stent body from being retracted due to the retraction of the thrombus removal stent during the withdrawal of the thrombus removal stent in the proximal direction. The effect of the withdrawal force causes the overall diameter of the tube to become smaller or kinked, thereby improving the efficiency of thrombus capture, and reducing the damage to the blood vessel wall caused by the thrombus removal stent. In this way, a smooth transitional connection between the first stent body and the second stent body is ensured, thereby reducing the damage to the blood vessel wall caused by the thrombus removal stent during the thrombus removal process.

The proximal end of the first stent body 10 is also provided with a connecting head 13. The connecting head 13 extends in a direction parallel to the central axis L of the bolt removal bracket 100. When the thrombus removal stent 100 is withdrawn, the traction force will be concentrated on the extension line where the connecting head 13 is located, which ensures that the diameter of the distal end of the stent body 101 remains unchanged, thereby improving the efficiency of thrombus capture.

In some embodiments, the connecting head 13 is provided with a developing positioning element 102, so that the position of the developing positioning element 102 can be used to indicate the position of the plug-removing bracket 2 under the detection of the instrument. The developing positioning member 102 is made of a radiopaque material. The radiopaque material is preferably a precious metal material such as gold, platinum, or tantalum. The developing positioning element 102 can take various forms such as ring shape, wire shape, ribbon shape, or dot shape, and is fixed to the bolt removal bracket 100 by means of pressing, hot melting, bonding, welding, or riveting, etc. commonly used in the art. superior. In some embodiments, the developing positioning element 102 may be ring-shaped, and the developing positioning element 102 is sleeved outside the connecting head 13.

In this embodiment, the proximal end of the thrombus retrieval stent 100 is provided with a visualization positioning element 102 to accurately locate the position of the thrombus, so that the thrombus can be captured during the thrombus retrieval process using the thrombus retrieval stent 100, and in the thrombus retrieval stent In the process of 100 withdrawal, it is determined whether the thrombus is separated from the thrombus removal stent 100 for real-time observation, and then the specific thrombus removal operation is guided, that is, the thrombus removal stent 100 is guided to switch between the compressed state and the released state, so that the thrombus removal is more accurate. In some other embodiments, the middle part of the thrombus removal stent 100 may also be provided with multiple visualization positioning elements to more accurately locate the position of the thrombus.

Please refer to Figure 3, which shows a schematic diagram of the bolt removal process of the bolt removal bracket. The blood vessel 200 includes a blood vessel wall 201, a blood flow channel 202 and a thrombus 203 that blocks the blood flow channel 202. In this embodiment, the thrombus 203 includes a first thrombus 2031 and a second thrombus 2032. The volume of the first thrombus 2031 is greater than the volume of the second thrombus 2032, and the second thrombus 2032 is a thrombus detached from the thrombus removal stent 100. The first thrombus 2031 is anchored on the first catching section 31 and the second catching section 33 of the second stent body 30. The second thrombus 2032 enters the mouth end 601 of the protective umbrella 6 from the first open end 103 of the stent body 101, passes through the extension portion 62 and is received in the recovery portion 64 of the protective umbrella 6. In this way, the first thrombus 2031 and the second thrombus 2032 can be removed from the blood vessel 200 by withdrawing the thrombus stent 100.

It can be understood that since the stent body 101 and the protective umbrella 6 are made of materials with shape memory effects, the thrombus removal stent 100 can be completely embedded in the thrombus 203 through the combined action of the compression and release of the stent body 101 and the protective umbrella 6. After waiting for a certain period of time, the embolic stent 100 is retracted to capture the thrombus 203. However, during the withdrawal process of the thrombus removal stent 100, when thrombus fragments or fragments (for example, the second thrombus 2032) fall off, due to the difference between the first open end 103 of the stent body 101 and the umbrella end 601 of the protective umbrella 6 The channel 1010 in the middle is unobstructed, and the second thrombus 2032 that falls off can enter the protective umbrella 6 of the dense mesh structure unobstructed, thereby effectively recovering the thrombus 203 in the blood vessel, ensuring the recanalization rate of the blood vessel, and avoiding the re-embolization of the patient’s blood vessel. .

The thrombus removal stent 100 provided by the embodiment of the present invention is based on the protective umbrella 6 provided at the distal end of the stent body 101, thereby effectively preventing the thrombus falling from the stent body 101 from escaping. In addition, the distal end of the stent body 101 forms a first open end 103, the proximal end of the protective umbrella forms an umbrella mouth end 601 directly opposite to the first open end 103, and the distal end of the protective umbrella 6 forms a The umbrella mouth end 601 is opposite to the sealing end 603, and the umbrella mouth end 601 is connected with the first open end 103, so that a continuous channel is formed inside the bolt removal bracket. In this way, the thrombus detached from the stent body 101 completely enters the protective umbrella 6 without being blocked, so that the protective umbrella 6 can effectively recover the thrombus detached from the stent body 101, thereby avoiding the problem of blood vessel re-embolization caused by the thrombus detached from the stent body 101 , And prevent complications caused by thrombus removal treatment, thereby increasing the recanalization rate of blood vessels. In addition, because the umbrella mouth end 601 is connected to the first open end 103, that is, the protective umbrella 6 is close to the distal end of the stent body 101, thereby preventing thrombus from escaping, and the protective umbrella 6 and the stent body 101 Synchronous release, so the protective umbrella 6 can quickly open the protective umbrella 6 with the help of the radial support force of the stent body 101 until the protective umbrella 6 is unfolded to a predetermined state to accommodate the thrombus detached from the stent body 101. In addition, based on a plurality of connecting pieces 107 with connecting holes 1071 provided at the distal end of the stent body 101, a plurality of connecting buckles 605 are arranged at the proximal end of the protective umbrella 6, and the connecting loops pass through the connecting holes 1071 and 1071 of each connecting piece 107. A plurality of connecting buckles 605 are used to connect the bracket body 101 and the protective umbrella 6 together. In this way, the connecting ring 8 can quickly open the protective umbrella 6 with the help of the radial support force of the stent body 101, and the design of the connecting ring can prevent the mouth end 601 of the protective umbrella 6 from collapsing and enhance the adhesion of the protective umbrella 6 to the blood vessel wall. Thereby improving the capture efficiency of thrombus.

Please refer to FIGS. 4 to 6 together. FIG. 4 is a schematic structural diagram of a bolt removing bracket 100h provided by a second embodiment of the present invention, and FIG. 5 is a structural diagram of a bracket body 101h of the bolt removing bracket 100h; Fig. 6 is a schematic diagram showing the structure of the protective umbrella 6h of the bolt-removing bracket 100h. In the second embodiment, the structure of the bolt removal bracket 100h is similar to the structure of the bolt removal bracket 100 of the first embodiment. The difference is that the mounting structure 104h, the connecting structure 602h, and the connecting piece 8h are different from the mounting structure 104, the connecting structure 602, and the connecting piece 8 in the first embodiment, and the protective umbrella 6h is not provided with a cylindrical extension.

In this embodiment, the mounting structure 104h is formed by enclosing a plurality of fixing rods 107h, and the plurality of fixing rods 107h are respectively arranged on the plurality of first bending structures 1061. The connecting structure 602h is surrounded by a plurality of connecting rods 605h. The connecting rods 605h are scattered on the corresponding second bending structure 6061h, and each connecting rod 605h is adjacent to the corresponding fixed rod 107h. The connecting piece 8 is constructed To connect the wire 8h, the connecting wire 8h is wound around the adjacent fixing rod 107h and the connecting rod 605h to connect the protective umbrella 6h and the bracket body 101h. In this way, the structures of the mounting structure 104h and the connecting structure 602h are simplified, and the processing and manufacturing of the bolt-removing bracket 100 is facilitated. In addition, by wrapping the connecting wire 8h around the adjacent fixing rod 107h and the connecting rod 605h, the stability and reliability of the connection between the bracket body 101h and the protective umbrella 6h are enhanced.

In some other embodiments, the connecting wire 8h may be omitted, that is, the fixing rod 107h and the connecting rod 605h may be directly fixedly connected together. The fixing method of the fixing rod 107h and the connecting rod 605h is, for example, but not limited to welding or bonding.

In some embodiments, the connecting wire 8h is a developing positioning element. The imaging positioning element is arranged at the junction of the stent body 101h and the protective umbrella 6h as a distal mark of the thrombus removal stent 100h, so as to more accurately locate the position of the thrombus and the protective umbrella 6h. In some other embodiments, the developing positioning element can be directly fixed on the connecting wire. The developing positioning element is, for example, but not limited to, a developing ring or a developing wire. The fixing method of the developing positioning element is, for example, but not limited to welding, crimping, hot melting or pressure riveting, and other common technical means in the art to be fixedly connected together.

The connecting rod 605h includes a plurality of bent sections 6051h and a straight section 6053h, and the straight section 6053h is formed by converging and braiding the plurality of bent sections 6051h to the straight section 6053h. In this way, it is possible to avoid the collapse of the mouth end 601h of the protective umbrella 6h.

The distal end of each bending section 6051h is connected to the middle of the corresponding second bending structure 6061h, and the plurality of bending sections 6051h are symmetrically distributed around the straight section 6053h, and the straight sections 6053h are arranged in two adjacent second bends. The outer side of the junction 6062h of the folded structure 6061h. In this way, the radial support force received by the mouth end 601h of the protective umbrella 6h is relatively uniform, which prevents the protective umbrella 6h from collapsing, thereby ensuring the adherence of the protective umbrella 6h, and can quickly open the protective umbrella 6h, thereby effectively capturing the thrombus in the blood vessel.

Wherein, the fixed rod 107h and the straight section connecting rod 6053h of the connecting rod 605h both extend in a direction parallel to the central axis L of the bolt removal bracket 100h. In this way, the overall flexibility of the thrombus removal stent 100h is ensured, the smooth movement of the stent body 101h and the protective umbrella 6h in the blood vessel is ensured, and the damage to the blood vessel wall is reduced.

In this embodiment, the net body 63h is configured as a conical recovery structure. The mesh body 63h is formed by a combination of a plurality of first mesh units 606h and a plurality of third mesh units 641h. The area of the plurality of third grid units 641h gradually increases from the distal end to the proximal end, and is smaller than the area of the first network port 106. Since the area of the plurality of third grid units 641h gradually increases from the distal end to the proximal end, that is, the grid design of the mesh body 63h is gradually dense from the proximal end to the distal end, preventing the thrombus entering the mesh body 63h from escaping. The thrombus that falls off or overflows in the stent body 101h is recovered to increase the recanalization rate of the blood vessel.

Please refer to FIGS. 7 and 8 together. FIG. 7 shows a schematic diagram of the structure of the net body 63h; FIG. 8 shows a bottom view of the net body 63h. The net body 63h is configured in a tapered kaleidoscope pattern. Specifically, the mesh body 63h is composed of a multi-layer flower-shaped ring structure 631h in the axial direction of the protective umbrella 6h. The multi-layer flower-shaped ring structures 631h are seamlessly connected to each other, and each layer of the flower-shaped ring structure 631h is composed of multiple mesh areas. The same third grid unit 641h is connected. Specifically, a third grid unit 641h of one layer of flower-shaped ring structure 631h faces the gap between two adjacent third grid units 641h of another layer of flower-shaped ring structure 631h, so as to make the protective umbrella 6 easier Compression can better adapt to small blood vessels.

The bolt removal stent 100h provided by the embodiment of the present invention is based on a plurality of fixing rods 107h arranged at the distal end of the stent body 101h, a plurality of connecting rods 605h are arranged at the proximal end of the protective umbrella 6h, and then the adjacent fixing rods are wound by connecting wires 8h 107h and connecting rod 605h to fix the bracket body 101h and the protective umbrella 6h together, which not only simplifies the entire structure of the bolt removal bracket 100h, facilitates the processing and manufacturing of the bolt removal bracket 100, and enhances the connection between the bracket body 101h and the protective umbrella 6h Stability and reliability.

Please refer to FIGS. 9 to 13 together. FIG. 9 is a schematic diagram of the structure of the peg-removing bracket 100a provided by the third embodiment of the present invention; FIG. 10 is an enlarged view of the partial structure of the bracket body 101a of the peg-removing bracket 100a 11 shows a schematic diagram of the bolt removal process of the bolt removal bracket 100a; FIG. 12 shows a cross-sectional view of the bracket body 101a in FIG. 11 along the XII-XII direction; FIG. 13 shows the bolt removal bracket 100a in FIG. 9 A schematic structural diagram of the entire structure of the stent body 101a in the semi-free state. In the third embodiment, the structure of the bolt removal bracket 100a is similar to the structure of the bolt removal bracket 100 of the first embodiment. The difference is that the bracket body 101a of the second embodiment is different from the bolt removal bracket 100 of the first embodiment. Among them, the first catching section in the first embodiment is configured as a large pipe diameter section 31a, and the second catching section in the first embodiment is configured as a small pipe diameter section 33a.

As shown in FIGS. 9 and 12, in this embodiment, the bolt removal bracket 100a includes a bracket body 101a. The stent body 101a is configured into a tubular structure, a cage structure, or a combination thereof. The stent body 101a includes a first stent body 10 and a second stent body 30a provided at the distal end of the first stent body 10. The second bracket body 30a includes a large pipe diameter section 31a, a small pipe diameter section 33a, and a transition section 35a. The large pipe diameter section 31a and the small pipe diameter section 33a are alternately connected, and the large pipe diameter section 31a and the small pipe diameter section 33a are connected by a transition section 35a. The plug-removing stent 100a has a semi-free state and a free state. In the semi-free state, at least part of the structure of the second stent body 30a is a single-layer tubular structure, and in the free state, the second stent body 30a is a double-layer Tubular structure.

It should be noted that in this embodiment, the semi-free state (ie, partially released state) means that at least part of the structure of the thrombus removal stent 100a is in an incompletely expanded working state, for example, when the thrombus removal stent 100a is implanted in a blood vessel In the early stage, the stent body 101a was compressed by thrombus; or the stent body 101a of the thrombus removal stent 100a was constrained by other restraining elements. The free state (that is, the completely released state) refers to the working state of the stent body 101a of the plug-removing stent 100a in a fully expanded state, or in a completely free state (that is, not restricted by other restraining elements). In some embodiments, as shown in FIG. 11, in the semi-free state, part of the structure of the stent body 101a is compressed by thrombus or constrained by restraining elements. In some other embodiments, as shown in FIG. 13, in the semi-free state, the overall structure of the stent body 101a is compressed by thrombus or restrained by restraining elements.

As shown in FIG. 9, in this embodiment, in the free state, the orthographic projection of the large pipe diameter section 31a on the first projection plane partially overlaps the orthographic projection of the small pipe diameter section 33a on the first projection plane. In this way, the radial support force of the thrombus removal stent 100a in blood vessels of different diameters is ensured, thereby effectively preventing the thrombus removal stent 100a from collapsing when the thrombus removal stent 100a completely passes through the blood vessel, thereby improving the efficiency of thrombus capture and reducing the embolization process. Damage to the blood vessel wall caused by the embolization stent 100a. As shown in FIG. 11, in the semi-free state, the orthographic projection of the large pipe diameter section 31a on the first projection plane and the orthographic projection of the small pipe diameter section 33a on the first projection plane do not overlap. The first projection plane is a plane parallel to the central axis L of the bolt removal bracket 100a. In this way, when the thrombus removal stent 100a is in a partially released state, the overall structure or part of the stent body 101a is a single-layer tubular structure with an approximate closed-loop structure, thereby reducing the entry of thrombus into the single-layer tubular structure, so that the thrombus removal stent is partially In the released state, there is a cavity for blood flow, thereby improving the safety of thrombectomy operation.

As shown in Figures 10 and 11, the second stent body 30a may include a first part in the semi-free state and a second part in the free state at the same time. The first part of the second stent body 30a is compressed by thrombus. , Temporarily in the semi-free state. Wherein, the first part has a single-layer tubular structure, and the second part has a double-layer tubular structure. The metal coverage rate of the outer peripheral surface of the single-layer tubular structure is greater than the metal coverage rate of the outer peripheral surface of the double-layer tubular structure. The metal coverage refers to the area ratio of the metal constituting the second bracket body 30a to the outer peripheral surface of the second bracket body 30a. In the first part in the semi-free state, the large pipe diameter section 31a is not fully opened, the diameter of the large pipe diameter section 31a is close to the diameter of the small pipe diameter section 33a, and the free end 3113a of the large pipe diameter section 31a is close to the small pipe The proximal connection point 3311a of the diameter section 33a, the proximal connection point 3111a of the large diameter section 31a is close to the free end 3313a of the small diameter section 33a, so that the cross section of the first part of the stent body 101a is approximately closed-loop structure 1011a (see Figure 12), that is, the cross-section of the single-layer tubular structure is approximately a closed-loop structure 1011a, so it can maintain a cavity for blood flow inside or on one side of the thrombus, and open the blood flow path before removing the thrombus to prevent long-term Poor blood flow damages the brain or other tissues.

Please refer to FIGS. 11 and 12 together. The blood vessel 200 includes a blood vessel wall 201, a blood vessel lumen 202, and a thrombus 203 blocking the blood vessel lumen 202. In this embodiment, the thrombus 203 includes a first thrombus 2031 and a second thrombus 2032. The volume of the first thrombus 2031 is greater than the volume of the second thrombus 2032, and the second thrombus 2032 is a thrombus detached from the thrombus removal stent 100. When the thrombus removal stent 100a is released into the blood vessel 200 with thrombus 203, the second thrombus 2032 enters the protective umbrella 6, and the structure of the stent body 101a of the thrombus removal stent 100a that is not compressed by the first thrombus 2031 can quickly expand and be in a completely released state , The structure of the stent body 101a compressed by the first thrombus 2031 will not expand and is in a partially released state. Specifically, the proximal and distal ends of the stent body 101a and the protective umbrella 6 are not compressed by the first thrombus 2031, so that the proximal and distal ends of the stent body 101a and the protective umbrella 6 enter a completely released state. In the completely released state, the proximal and distal ends of the stent body 101a are attached to the blood vessel wall 201. At this time, the mesh of the stent body 101a is relatively large, and the proximal and distal ends of the thrombus removal stent 100a are connected to the blood flow channel 202. The middle part of the stent body 101a is compressed by the first thrombus 2031, so that the middle part of the stent body 101a cannot be fully deployed and is in a partially released state. In the partially released state, there is a gap between the middle of the stent body 101a and the blood vessel wall 201 of the blood vessel 200. At this time, the mesh of the stent body 101a is small, and the middle of the stent body 101a can form a continuous single-layer tubular structure with an approximate closed-loop structure, and the lumen 1012a of the single-layer tubular structure is connected to the blood flow channel 202, that is, The thrombus removal stent 100a quickly establishes a blood flow channel and realizes the pre-passing function of the blood flow channel, thereby improving the safety of thrombus removal. In addition, when the middle part of the stent body 101a expands and enters the fully released state, the middle part of the stent body 101a expands in the thrombus until the middle part of the stent body 101a is in contact with the blood vessel wall 201, so that the first thrombus 2031 enters the stent body In 101a, the thrombus 203 can be removed from the blood vessel 200 by retracting the thrombus stent 100a.

Please refer to Figure 9, Figure 11 and Figure 12 again. In this embodiment, the single-layer tubular structure is a continuous tubular structure formed by the large pipe diameter section 31a and the small pipe diameter section 33a, so that the single layer tubular structure It has a continuous lumen 1012a, in which the maximum diameter of the large diameter section 31a is approximately equal to the maximum diameter of the small diameter section 33a, so as to realize the pre-passing function of the blood flow channel in the early stage of thrombus removal. The double-layer tubular structure includes a discontinuous inner tube structure composed of a small diameter section 33a and a discontinuous outer tube structure composed of a large diameter section 31a, wherein the maximum diameter of the large diameter section 31a is larger than that of the small diameter section The maximum diameter of 33a.

Wherein, the outer diameter of the large pipe diameter section 31a of the single-layer tubular structure is smaller than the minimum outer diameter of the large pipe diameter section 31a of the double-layer tubular structure. The outer diameter of the large pipe diameter section 31a of the single-layer tubular structure is approximately equal to the outer diameter of the small pipe diameter section 33a of the single-layer tubular structure. The outer diameter of the small pipe diameter section 33a of the single-layer tubular structure is smaller than the outer diameter of the small pipe diameter section 33a of the double-layer tubular structure, that is, the outer diameter of the single-layer tubular structure is smaller than the diameter of the inner pipe structure of the double-layer tubular structure. The large pipe diameter section 31a, the small pipe diameter section 33a and the transition section 35a are coaxially arranged. In some embodiments, the large diameter section 31a, the small diameter section 33a, and the transition section 35a are integrally formed to improve the stability and reliability of the second bracket body 30a. In some other embodiments, the large pipe diameter section 31a, the small pipe diameter section 33a, and the transition section 35a may also be fixedly connected together by technical means commonly used in the art, such as crimping, hot melting, bonding, welding, or pressure riveting.

In some embodiments, both the proximal and distal ends of the second stent body 30a are configured as a large diameter section 31a, the small diameter section 33a is arranged between two adjacent large diameter sections 31a, and the large diameter section 31a is sleeved Set outside the transition section 35a. In some other embodiments, the proximal end of the second stent body 30a is configured as a large diameter section 31a, and the distal end of the second stent body 30a is configured as a small diameter section 33a. In this embodiment, the second stent body 30a includes 4 large pipe diameter sections 31a and three small pipe diameter sections 33a. The two large diameter sections 31a are respectively located at the proximal and distal ends of the second stent body 30a, and the other two large diameter sections 31a are located in the middle of the second stent body 30a. The small pipe diameter section 33a is located between two adjacent large pipe diameter sections 31a. In this way, the structural design of the large diameter section 31a, the small diameter section 33a, and the transition section 35a can improve the flexibility of the thrombus removal stent 100a, and can enhance the anchoring effect of thrombus. Further, the thrombus removal stent 100a has a certain radial and axial support force, thereby effectively preventing the thrombus removal stent 100a from collapsing when it completely passes through the blood vessel, thereby improving the efficiency of thrombus capture, and reducing the amount of thrombus removal during thrombus removal. Damage to the blood vessel wall caused by the embolization stent 100a. In addition, when the thrombus removal stent 100a is squeezed in a blood vessel, it can make a large deformation, so that it can adapt to blood vessels of different bending shapes and different diameters, and can ensure the adhesion of the stent body 101a to the blood vessel wall to further Improve the efficiency of bolt removal. Therefore, the existing thrombectomy stent requires a large radial size of the catheter and cannot pass through tortuous intracranial blood vessels, while the thrombectomy stent 100a of the present application requires a small radial size within the catheter, so it is suitable for smaller intracranial and other smaller diameters. Blood vessel.

It should be noted that the number of the large pipe diameter section 31a and the small pipe diameter section 33a can be set according to actual requirements, and the present invention is not limited.

In some embodiments, the large-diameter section 31a is configured as an equal-diameter tubular structure. In the semi-free state, the diameter of the large-diameter section 31a is approximately equal to the diameter of the small-diameter section 33a; in the free state, The diameter of the large pipe diameter section 31a is larger than the diameter of the small pipe diameter section 33a. In this way, the integrated laser cutting and molding of the embolization stent 100a is convenient, and the accommodation space between the large diameter section 31a and the small diameter section 33a is enlarged, so that the thrombus can easily enter the channel 1010a inside the embolization removal stent 100a, and Avoid cutting the thrombus, thereby improving the efficiency of capturing the thrombus.

In some other embodiments, the large pipe diameter section 31a is configured as a reduced-diameter tubular structure, and the reduced-diameter tubular structure is an olive-like bidirectional cone-shaped cone with a large middle and small ends. In the semi-free state, at least The diameter of the middle area of part of the large pipe diameter section 31a is approximately equal to the diameter of the small pipe diameter section 33a; in the free state, the diameter of the middle area of the large pipe diameter section 31a is larger than the diameter of the small pipe diameter section 33a. In this way, the flexibility of the thrombus removal stent 100a sliding in the blood vessel is further improved, so that the damage to the blood vessel wall caused by the thrombus removal stent 100a during the embolization process can be reduced. Among them, in order to take into account the flexibility of the plug removal stent 100a, the capture efficiency of the plug removal stent 100a, and the radial and axial support force of the plug removal stent 100a, the ratio of the maximum diameter to the minimum diameter of the large diameter section 31a is 1.5:1 To 3:1.

Please refer to FIGS. 9 and 10 together. In the present embodiment, the large diameter section 31a of the bolt removal bracket 100a is formed by a plurality of first closed loop units 311a. The small pipe diameter section 33a is formed by a plurality of second closed loop units 331a. The transition section 35a is formed by enclosing a plurality of support rods 350a.

Specifically, the plurality of support rods 350a include a plurality of first support rods 351a and a plurality of second support rods 352a. The plurality of first support rods 351a and the plurality of second support rods 352a are arranged at intervals along the circumferential direction of the second bracket body 30a. A plurality of first support rods 351a are arranged at the proximal end of the small tube diameter section 33a, and a plurality of second support rods 352a are arranged at the distal end of the small tube diameter section 33a at intervals.

The first closed loop unit 311a includes a proximal connection point 3111a, a middle connection point 3112a, and a free end 3113a, and the second closed loop unit 331a includes a proximal connection point 3311a, a middle connection point 3312a, and a free end 3313a. The distal end of the first support rod 351a is connected to the proximal connection point 3311a of the second closed-loop unit 331a, the proximal end of the first support rod 351a is connected to the middle connection point 3112a of the first closed-loop unit 311a; the distal end of the second support rod 352a is connected The proximal end of the first closed loop unit 311a is connected to the point 3111a, and the proximal end of the second support rod 352a is connected to the central connection point 3312a of the second closed loop unit 331a. The free end 3113a of the first closed loop unit 311a is directly opposite to the proximal connection point 3111a, and the free end 3113a of the second closed loop unit 331a is directly opposite to the proximal connection point 3311a. The

free endpoints

3113a and 3313a can be embedded in the thrombus to improve the capture rate of the thrombus.

In the process of switching from the semi-free state to the free state, the free end 3113a of the first closed-loop unit 311a is opposite to the second closed-loop unit 311a that is opposite to the distal end of the first closed-loop unit 311a and is adjacent to the first closed-loop unit 311a. The radial distance between the proximal connection point 3311a of the closed loop unit 331a gradually increases, and the proximal connection point 3111a of the first closed loop unit 311a is opposite to the proximal end of the first closed loop unit 311a and is opposite to the first closed loop unit 311a. The radial distance between the free end points 3313a of the adjacent second closed-loop units 331a also gradually increases.

In the process of switching from the free state to the semi-free state, the free end 3113a of the first closed-loop unit 311a is opposite to the second closed-loop unit 311a that is opposite to the distal end of the first closed-loop unit 311a and is adjacent to the first closed-loop unit 311a. The radial distance between the proximal connection point 3311a of the closed loop unit 331a gradually decreases, and the proximal connection point 3111a of the first closed loop unit 311a is opposite to the proximal end of the first closed loop unit 311a and is opposite to the first closed loop unit 311a. The radial distance between the free end points 3313a of the adjacent second closed-loop units 331a also gradually decreases. Therefore, in the semi-free state, the first closed-loop unit 311a and the second closed-loop unit 331a together form a continuous tubular structure close to a closed loop with a large metal coverage, thereby forming a blood flow channel in the thrombus for blood flow. Through this, the safety of thrombus removal is improved.

Wherein, at the junction of the large pipe diameter section 31a and the small pipe diameter section 33a, the free end 3113a of the first closed loop unit 311a is adjacent to the proximal end connection point 3311a of the second closed loop unit 331a adjacent to the distal end of the first closed loop unit 311a , Arranged alternately along the circumferential direction of the second stent body 30a to form a first annular array 3010a. The free end points 3313a are alternately arranged along the circumferential direction of the second bracket body 30a to form a second annular array 3012a.

In this embodiment, the radial distance is the linear distance between the adjacent free end 3113a and the proximal connection point 3311a at the junction of the large diameter section 31a and the small diameter section 33a, or the large diameter section The linear distance between the adjacent free end 3313a at the junction of 31a and the small diameter section 33a and the proximal connection point 3111a. Specifically, the radial distance is the linear distance between the adjacent free end points 3113a and the proximal connection point 3311a in the first annular array 3010a; or the adjacent

free end points

3313a and 3313a in the second annular array 3012a The linear distance between the proximal connection points 3111a.

In the semi-free state, the proximal connection point 3311a and the free end point 3113a in the first annular array 3010a are coplanar, and the proximal connection point 3111a and the free end point 3313a in the second annular array 3012a are also coplanar to ensure The thrombus stent 100a has radial and axial supporting forces as a whole, while ensuring that the first closed-loop unit 311a and the second closed-loop unit 331a have a relatively small area to prevent thrombus from entering the channel 1010a inside the thrombus removal stent 100a, thereby Realize the pre-pass function of the blood flow channel. It should be noted that the proximal connection point 3311a and the free end 3113a in the first annular array 3010a are coplanar, meaning that the proximal connection points 3311a in the first annular array 3010a are connected to each other to form a first plane, and the first annular array 3010a The free end points 3113a in are connected to each other to form a second plane, and the first plane and the second plane are coplanar, that is, the first plane and the second plane are located on the same plane and coincide with each other. The proximal connection point 3111a in the second annular array 3012a and the free end 3313a are coplanar, meaning that the proximal connection points 3111a in the second annular array 3012a are connected to each other to form a third plane, and the free end 3313a in the second annular array 3012a They are connected to each other to form a fourth plane, and the third plane and the fourth plane are coplanar, that is, the third plane and the fourth plane are located on the same plane and overlap each other. Wherein, the first plane, the second plane, the third plane and the fourth plane are perpendicular to the central axis L of the bolt removal bracket 100a.

In the free state, the proximal connection point 3311a and the free end point 3113a in the first circular array 3010a are not coplanar, and the proximal connection point 3111a and the free end point 3313a in the second circular array 3012a are also not coplanar, thereby improving The smoothness of the plug-removing bracket 100a from the free state to the semi-free state, and ensuring that the whole of the plug-removing bracket 100a has radial and axial supporting forces, while ensuring the first closed-loop unit 311a and the second closed-loop unit The 331a has a relatively large area so that the thrombus can enter the channel 1010a inside the thrombus removal stent 100a, thereby improving the efficiency of capturing the thrombus. It should be noted that the proximal connection point 3311a and the free end 3113a in the first annular array 3010a are not coplanar, which means that the proximal connection points 3311a in the first annular array 3010a are connected to each other to form a first plane. The free ends 3113a in 3010a are connected to each other to form a second plane, and the first plane and the second plane are not coplanar, that is, the first plane and the second plane are on different planes and are parallel to each other. The proximal connection point 3111a in the second annular array 3012a and the free end 3313a are not coplanar, meaning that the proximal connection points 3111a in the second annular array 3012a are connected to each other to form a third plane, and the free end in the second annular array 3012a 3313a are connected to each other to form a fourth plane, and the third plane and the fourth plane are not coplanar, that is, the third plane and the fourth plane are located on different planes and are parallel to each other.

Wherein, in the process of switching from the semi-free state to the free state, the length of the plug-removing bracket 100a gradually decreases, the outer diameter of the plug-removing bracket 100a gradually increases, and the area of the first closed-loop unit 311a and the second The area of the closed loop unit 331a also gradually increases. Specifically, in the semi-free state, the plug-removing stent 100a is radially compressed to stretch the length of the plug-removing stent 100a, and the plug-removing stent 100a has a relatively small outer diameter, the area of the first closed-loop unit 311a and the second The area of the closed loop unit 331a is relatively small. In the free state, the plug removal stent 100a expands radially to shorten the length of the plug removal stent 100a, and the plug removal stent 100a has a relatively large outer diameter, the area of the first closed-loop unit 311a and the area of the second closed-loop unit 331a relatively bigger.

When the bracket body 101a is in the semi-free state, the plurality of first support rods 351a and the plurality of second support rods 352a are in a straight rod-like structure; when the bracket body 101a is in the free state, the plurality of first support rods 351a The second support rods 352a and the plurality of second support rods 352a are in a curved structure, and are bent inward or outward relative to the second bracket body 30a. In this way, in the free state, since the plurality of first support rods 351a and the plurality of second support rods 352a are in a curved structure, the cutting of the thrombus can be reduced, and more accommodating space can be provided for the thrombus. This allows the thrombus to enter the inner cavity of the thrombus removal stent 100a, thereby improving the capture efficiency of the thrombus removal stent 100a. In the semi-free state, since the plurality of first support rods 351a and the plurality of second support rods 352a are in a straight rod-like structure, and the plurality of first support rods 351a and the plurality of second support rods 352a are substantially parallel to the

first support rods

351a and 352a. The axial direction of the two stent bodies 30a, so that the entire thrombus removal stent 100a can be compressed to form a single-layer tubular structure with a closed loop structure 1011a with approximately the same outer diameter, so as to realize the pre-passing function of the blood flow channel.

The area of the first closed-loop unit 311a is larger than the area of the second closed-loop unit 331a. The shapes of the first closed-loop unit 311a and the second closed-loop unit 331a include one or more of a rhombus, a circle, an ellipse, a triangle, a trapezoid, and a hexagon.

In this embodiment, the first closed-loop unit 311a and the second closed-loop unit 331a are both diamond-shaped or nearly diamond-shaped structures. The large pipe diameter section 31a is surrounded by four first closed-loop units 311a to form a tubular structure. Each first closed loop unit 311a has two middle connection points 3112a. Two adjacent first closed-loop units 311a are connected together by a middle connection point 3112a. The small pipe diameter section 33a is surrounded by three second closed loop units 331a to form a tubular structure. Each second closed loop unit 331a has two middle connection points 3312a. Two adjacent second closed-loop units 331a are connected together by a middle connection point 3312a. Wherein, the area of the first closed-loop unit 311a is larger than the area of the second closed-loop unit 331a. The plurality of first closed-loop units 311a and the plurality of second closed-loop units 331a are staggered, so that the second closed-loop unit 331a is arranged between two adjacent first closed-loop units 311a, so that the bolt removal bracket 100a is more easily compressed and more capable It is suitable for small blood vessels and is easy to introduce into the micro catheter.

The distal end of the first closed loop unit 311a forms a first capture unit 3114a, and the distal end of the second closed loop unit 331a forms a second capture unit 3314a. The first catching unit 3114a and the first support rod 351a are alternately arranged and connected to each other, and the second catching unit 3314a and the second support rod 352a are alternately arranged and connected to each other, which not only ensures the flexibility of the bolt removal bracket 100a, but also makes the removal The thrombus stent 100a has a certain supporting force in the radial and axial directions, and the thrombus capture efficiency of the thrombus removal stent 100a is improved.

Among them, the two middle connection points 3112a of the first closed loop unit 311a are connected to the free end 3113a to form the first catching unit 3114a. The two middle connection points 3312a of the second closed loop unit 331a are connected to the free end 3313a to form a second catching unit 3314a. The first catching unit 3114a and the second catching unit 3314a may have a V-shaped, W-shaped, zigzag, or U-shaped structure to improve the efficiency of capturing thrombus.

The first catching unit 3114a and the second catching unit 3314a are alternately arranged, that is, the second catching unit 3314a is arranged between two adjacent first catching units 3114a so as to cover the radial direction of the bolt-removing stent 100a. Capture unit, thereby improving the anchoring effect of thrombus. The first catching unit 3114a and the second catching unit 3314a and the bracket body 101a respectively form a first receiving space 3115a and a second receiving space 3315a that are opposed to each other. Both the first catching unit 3114a and the second catching unit 3314a extend outward or inward with respect to the bracket body 101a. The bending direction of the first catching unit 3114a and the second catching unit 3314a is opposite to the bending direction of the first support rod 351a and the second support rod 352a. In this way, the space of the first accommodating space 3115a and the second accommodating space 3315a is increased, which can provide more accommodating space for the thrombus so that the thrombus can enter the inner cavity of the thrombus removal stent 100a, thereby further improving the thrombus removal stent 100a The capture efficiency. When the thrombus removal stent 100a is in the free state (that is, the expanded state), the first catching unit 3114a and the second catching unit 3314a are inserted into the thrombus, or the thrombus is clamped in the first housing space 3115a and the second housing In the space 3315a, the anchorage of the thrombus by the thrombus removal stent 100a is improved. Since the first catching unit 3114a and the second catching unit 3314a are evenly distributed in the circumferential direction of the stent body 101a, the flexibility of the thrombus removal stent 100a is enhanced, and the efficiency of catching thrombus is also improved.

The first catching unit 3114a and the second catching unit 3314a can move in a direction perpendicular to the axis L of the bolt removal bracket 100a. In this way, when the thrombus removal stent 100a moves in the blood vessel, the first grasping unit 3114a and the second grasping unit 3314a do not directly contact the blood vessel wall, thereby avoiding damage to the blood vessel wall tissue.

Further, the distal end of the first capture unit 3114a and the distal end of the second capture unit 3314a are both provided with arc-shaped chamfers to further avoid the distal end of the first capture unit 3114a and the second capture unit 3114a. 3314a damages the blood vessel wall.

In some embodiments, the first bracket body 10 and the second bracket body 30a are integrally formed so as to improve the stability and reliability of the connection between the first bracket body 10 and the second bracket body 30a. In some other embodiments, the first bracket body 10 and the second bracket body 30a may also be fixedly connected together by technical means commonly used in the art, such as pressing, hot melting, bonding, welding, or pressure riveting.

In this embodiment, the distal end of the second stent body 30a is completely open to form a first open end 301a, the proximal part of the first stent body 10 is open to form a second open end 15, and the first open end 301a is at the second open end 301a. The orthographic projection of the projection plane overlaps the orthographic projection of the second opening end 15 on the second projection plane; wherein, the second projection plane is a plane perpendicular to the central axis L of the bolt removal bracket 100a. In this way, the flexibility of the proximal and distal ends of the thrombus removal stent 100a is improved.

In some embodiments, the first bracket body 10a and the second bracket body 30a are integrally formed so as to improve the stability and reliability of the connection between the first bracket body 10a and the second bracket body 30a. In some other embodiments, the first bracket body 10a and the second bracket body 30a may also be fixedly connected together by technical means commonly used in the art, such as pressing, hot melting, bonding, welding, or pressure riveting.

In this embodiment, the distal end of the second stent body 30a is completely opened to form a first open end 301a, the proximal part of the first stent body 10a is opened to form a second open end 15, and the first open end 301a is at the second open end 301a. The orthographic projection of the projection plane overlaps the orthographic projection of the second opening end 15 on the second projection plane; wherein, the second projection plane is a plane perpendicular to the central axis L of the bolt removal bracket 100a. In this way, the flexibility of the proximal and distal ends of the thrombus removal stent 100a is improved.

The protective umbrella 6 is directly connected to the distal end of the second bracket body 30a. The proximal end of the protective umbrella 6 forms an umbrella mouth end 601, and the distal end of the protective umbrella 6 forms a first sealed end 603 directly opposite to the umbrella mouth end 601. The umbrella mouth end 601 communicates with the first open end 301a, so that the bolt removal bracket 100a A continuous channel 1010a is formed inside.

The bolt removal stent 100a provided by the embodiment of the present invention is based on the design of the second stent body 30a such that the large pipe diameter section 31a and the small pipe diameter section 33a are alternately connected, and the large pipe diameter section 31a and the small pipe diameter section 33a pass through the transition The segments 35a are connected together. Therefore, in the semi-free state, at least part of the structure in the stent body 101a is approximately a single-layer tubular structure, and the grid space on the single-layer tubular structure is small, so as to prevent all the thrombus from entering the embolization stent 100a. The cavity causes the sealing problem of the inner cavity, so the single-layer tubular structure can be used as a blood flow channel. In addition, when the thrombus retrieval stent 100a is in the semi-free state, the single-layer tubular structure ensures the radial support force of the entire thrombus retrieval stent 100a, so that the thrombus retrieval stent 100a can quickly establish a blood flow channel before the thrombus is removed. The blood flow of the blocked blood vessel is restored, and the pre-pass function of the blood flow channel is realized in the early stage of thrombus removal, so as to improve the safety of thrombus removal. Since in the free state, the stent body 101a has an approximately double-layered tubular structure, the large diameter section 31a has a larger grid structure, and there is a certain space between the large diameter section 31a and the small diameter section 33a, Thus, all the thrombus is allowed to enter the inner cavity of the thrombus removal stent 100a, thereby improving the efficiency of thrombus removal. Further, the plug removal stent 100a adopts a segmented design, that is, the large pipe diameter section 31a and the small pipe diameter section 33a are sequentially spaced and evenly arranged, so as to improve the flexibility of the plug removal device and ensure that the plug removal stent 100a can It adapts to blood vessels with different curved shapes and can also enhance the anchoring effect of thrombus. For example, when the blood vessel is squeezed, the thrombus removal stent 100a can make greater deformation.

It should be noted that the structural design of the large pipe diameter section 31a, the small pipe diameter section 33a and the auxiliary capture unit 50a of the plug removal bracket 100a of the third embodiment is suitable for the plug removal in the first embodiment and the second embodiment.

Brackets

100, 100h, will not be repeated here. The connection design of the bracket body 101h and the protective umbrella 6h of the second embodiment is applicable to the third embodiment.

Please refer to FIGS. 14 and 15 together. FIG. 14 shows a schematic structural diagram of a thrombus removal bracket 100b provided by a fourth embodiment of the present invention; Schematic diagram of the structure from one angle. In the fourth embodiment, the structure of the bolt removing bracket 100a is similar to the structure of the bolt removing bracket 100a of the third embodiment. The difference is that the stent body 101b of the bolt removal stent 100b further includes a third stent body 40b, and the distal end of the second stent body 30b is a small tube diameter section 33.

As shown in FIG. 14, the distal end of the second stent body 30b is completely open to form a first open end 301b. The third stent body 40b is connected between the second stent body 30b and the protective umbrella 6, the proximal end of the third stent body 40b forms a third open end 401b, the distal end of the third stent body 40b forms a fourth open end 403b, and the protective umbrella 6 The proximal end of the protective umbrella 6 forms an umbrella end 601, the distal end of the protective umbrella 6 forms a first closed end 603 directly opposite to the umbrella end 601, the first open end 301b and the third open end 401b, the fourth open end 403b and the umbrella end 601 is connected, so that a continuous channel 1010b is formed inside the bolt removal bracket 100b.

Since the distal end of the thrombus removal stent 100b is provided with a protective umbrella 6, thereby effectively preventing the thrombus falling off from the thrombus removal stent 100b from escaping. In addition, the distal end of the stent body 101b forms a fourth open end 403b, the proximal end of the protective umbrella 6 forms an umbrella mouth end 601 directly opposite to the fourth open end 403b, and the distal end of the protective umbrella 6 forms an umbrella mouth end 601 directly opposite to the The first sealed end 603, the umbrella end 601 and the fourth open end 403b are connected, so that a continuous channel 1010b is formed inside the bolt removal bracket 100b. In this way, the thrombus detached from the thrombus removal stent 100b completely enters the protective umbrella 6 without being blocked, so that the protective umbrella 6 can effectively recover the thrombus detached from the thrombus removal stent 100b, thereby avoiding blood vessels caused by the thrombus falling off the thrombus removal stent 100b Re-embolization problems and prevent complications caused by thrombectomy treatment, thereby increasing the recanalization rate of blood vessels. In addition, because the umbrella mouth end 601 is connected to the fourth open end 403b, that is, the protective umbrella 6 is close to the distal end of the stent body 101b, so as to prevent thrombus from escaping, and the thrombus removal stent 100b and the protective umbrella 6 can be released synchronously, thereby protecting the umbrella 6. The protective umbrella 6 can be quickly opened with the help of the radial support force of the stent body 101b until the protective umbrella 6 is deployed to a predetermined state, so as to recover the thrombus detached from the stent body 101b.

In this embodiment, the proximal end of the third stent body 40b and the distal end of the second stent body 30b are smoothly transitionally connected, and the proximal end of the third stent body 40b and the distal end of the second stent body 30b are connected by a transition section 35 Together.

Specifically, the third bracket body 40b includes a capturing section 41b and an extension section 42b connecting the capturing section 41b and the protective umbrella 6. The proximal end of the capturing section 41b is connected to the small diameter section 33 of the second stent body 30b through a plurality of second support rods 352, and the distal end of the capturing section 41 is connected to the proximal end of the extension section 42b. Among them, the catching section 41b and the extension section 42b are smoothly transitionally connected, so as to ensure the overall flexibility of the bolt removal bracket 100b, and improve the safety of the bolt removal.

In some embodiments, the outer diameter of the capturing section 41b is greater than or substantially equal to the maximum outer diameter of the second stent body 30b, and is substantially equal to the outer diameter of the extension section 42b. In this way, the radial and axial supporting force of the thrombus removal stent 100b is ensured, and all thrombi that fall off or overflow in the second stent body 30b can enter the channel 1010b inside the third stent 40b from the capture section 41b.

As shown in Figs. 14 and 15, the capturing section 41b includes at least one capturing portion 43b and a plurality of reinforcing portions 44b. At least one catching portion 43b and a plurality of reinforcing portions 44b are connected side by side along the circumferential direction of the third bracket body 40b, and the shape of the catching portion 43b is different from the shape of the reinforcing portion 44b. In some embodiments, the number of the capturing portions 43b corresponds to the number of the reinforcing portions 44b, and the capturing portions 43b and the reinforcing portions 44b are alternately connected along the circumferential direction of the third bracket body 40b. In this embodiment, the capturing section 41b includes two diametrically opposed capturing portions 43b and two diametrically opposed reinforcing portions 44b, and each capturing portion 43b and each reinforcing portion 44b are arranged side by side and alternately connected along the circumferential direction of the third bracket body 40b. . In this way, the second mesh port 411b not only improves the capture performance of the second stent body 30b that is not effectively captured by the second stent body 30b, such as hard thrombi such as organic thrombus, calcified thrombus and larger thrombus, but also ensures the third stent body. The radial support force of 40b prevents excessive deformation of the third stent body 40b and reduces the adherence of the capturing section 41b, that is, prevents the capturing section 41b of the third stent body 40b from collapsing, and enhances the adherence of the capturing section 41b , In order to improve the efficiency of capturing thrombus.

It should be noted that the number of the capturing portion 43b and the reinforcing portion 44b is based on the diameter of the third stent body 40b, the number of the first closed loop units 311 used to form the large pipe diameter section 31, or the number of the first closed loop unit 311 used to form the small pipe diameter section 33 together. The number of the two closed-loop units 331 is designed based on factors such as the number of the two closed-loop units 331, which is not limited in the present invention.

Wherein, each capturing portion 43b includes a second mesh port 411b, and each reinforcing portion 44b includes a third mesh port 413b and a skeleton rod 415b arranged at the proximal end of the third mesh port 413b, wherein the area of the second mesh port 411b is larger than The area of the first network port 421b, the first closed-loop unit 311 and the second closed-loop unit 331, the area of the third network port 413b is equal to the area of the first network port 421b and the area of the first closed-loop unit 311, and the third network port 413b The shape of is the same as the shape of the first mesh port 421b and the shape of the first closed loop unit 311 to enhance the overall flexibility of the bolt removal bracket 100b. In some other embodiments, each reinforcing part may not include a skeleton rod, that is, each reinforcing part may include a plurality of third mesh ports connected in parallel along a direction parallel to the central axis L of the bracket body.

In this embodiment, the extension section 42b is formed by enclosing a plurality of first mesh openings 421b. The capturing section 41b is formed by at least one second mesh port 411b, a plurality of third mesh ports 413b, and a skeleton rod 415b. The first network port 421b, the second network port 411b, the third network port 413b, and the skeleton rod 415b are connected to each other to form a third bracket body 40b having a tubular structure or a cage structure.

The second network port 411b is directly opposite to the second closed-loop unit 331, that is, the second network port 411b is disposed between two adjacent first closed-loop units 311. The third network port 413b is directly opposite to the second closed-loop unit 311, that is, the second network port 411b is disposed between two adjacent first closed-loop units 311. In this way, it is ensured that the second mesh port 411b has a relatively large area, so as to improve the ability of the thrombus removal stent 100b to capture hard thrombi such as organic thrombus, calcified thrombus and larger thrombus, and to ensure the axial direction of the thrombus removal stent 100b Together with the radial support force, the thrombus can more easily enter the channel 1010b inside the third stent body 40b from the second mesh port 411b.

The proximal end of each second mesh port 411b is formed with a third catching unit 4114b, the proximal end of the third catching unit 4114b is connected to the distal end of the second support rod 352, and the distal end of the third catching unit 4114b is configured as Free end. Among them, the third capturing unit 4114b constitutes a part of the second net port 411b.

In this embodiment, the third capturing unit 4114b is configured in a V-shaped, W-shaped, zigzag, or U-shaped structure, and the third capturing unit 4114b is disposed between two adjacent second support rods 352. The third catching unit 4114b is directly opposite to the second catching unit 3314, and is arranged between two adjacent first catching units 3114. The third catching unit 4114b is arranged between two adjacent second support rods 352 and connected to each other.

Specifically, the first network port 421b includes a proximal connection point 4211b and two middle connection points 4212b. Two adjacent first network ports 421b are connected by a middle connection point 4212b. The second network port 411b includes two proximal connection points 4111b, a free end 4112b, and a distal connection point 4113b directly opposite to the free end 4112b. The third network port 413b includes a proximal connection point 4131b, two middle connection points 4132b, and a distal connection point 4133b directly opposite to the proximal connection point 4131b. The middle connection point 4212b of the first network port 421b coincides with the remote connection point 4113b of the second network port 411b and the remote connection section 4133b of the third network port 413b. The proximal connection point 4211b of the first network port 421b coincides with the middle connection point 4132b of the third network port 413b.

Wherein, the axial projection of each second network port 411b is approximately heart-shaped. Each proximal connection point 4111b of the capturing section 41b is connected to the distal end of the corresponding second support rod 352. The two proximal connection points 4111b of each second network port 411b and the free end 4112b are connected to form a V-shaped or U-shaped third capturing unit 4114b. The third catching unit 4114b extends outward or inward relative to the bracket body 101b, and forms a third accommodating space 4115b between the bracket body 101b. In this way, thrombi that cannot be effectively captured by the second stent body 30b, such as hard thrombi such as organic thrombus, calcified thrombus and larger thrombus, can enter the protective umbrella 6 through the second mesh port 411b. In addition, the thrombus falling off or overflowing from the second stent body 30b easily enters the protective umbrella 6 through the second mesh port 411b, thereby avoiding the problem of blood vessel re-embolization caused by the thrombus falling off or overflowing from the thrombus removal stent 100b and not effectively grasped. , And prevent complications caused by thrombus removal treatment, such as vasospasm, thereby increasing the recanalization rate of blood vessels.

In this embodiment, the skeleton rod 415b is configured in a Y-shaped structure. The skeleton rod 415b includes a first reinforcing rod 4151b and a second reinforcing rod 4153b connected between the first reinforcing rod 4151b and the third mesh opening 413b. The first reinforcing rod 4151b is configured in a V-shaped structure. The shape of the first reinforcing rod 4151b is the same as that of the third catching unit 4114b, and the shape of the distal end of the second mesh port 411d is the same as the shape of the distal end of the third mesh port 413d, so as to ensure the radial resistance of the capturing section 41b. The force balances and the smoothness of the capture section 41b, and enhances the adhesion of the capture section 41b, and improves the capture rate of thrombus. The shape of the second reinforcing rod 4153b is the same as that of the second support rod 352, and the shape of the third net port 413b is the same as the shape of the first net port 421b to ensure the flexibility of the bracket body 101b and make the bracket body 101b It has a certain supporting force in the radial and axial directions, and improves the capture efficiency of the stent body 101b for thrombus.

The second network port 411b is directly opposite to the second closed-loop unit 331, that is, the second network port 411b is disposed between two adjacent first closed-loop units 311. The number of second network ports 411b is equal to the number of second closed loop units 331. The second catching unit 3314 of the second bracket body 30b is close to the third catching unit 4114b of the third bracket body 40b, and the bending direction of the second catching unit 3314 is consistent with the bending direction of the third catching unit 4114b, so as to ensure The flexibility of the thrombus removal stent 100b is improved, and the anchoring effect on thrombus can be further improved. The second mesh port 411b is parallel to the opposite sides of the central axis L of the bracket body 101b respectively connected with a third mesh port 413b and a skeleton rod 415b connected in parallel along the direction of the central axis L, and each third mesh port 413b is arranged in the skeleton Between the rod 415b and the first mesh port 421b, the radial extension space of the second mesh port 411b is increased to increase the area of the second mesh port 411b, and to enhance the adhesion of the capturing section 41b to The thrombus enters the channel 1010b inside the third stent body 40b from the second mesh port 411b.

The bolt removal stent 100b provided by the embodiment of the present invention is provided with a third stent body 40b, and the proximal end of the third stent body 40b is provided with a second network port 411b with a larger network port area, and the proximal end of the second network port 411b The third capture unit 4114b is formed so that the third capture unit 4114b can anchor the thrombus that the second stent body 30b does not effectively capture, such as hard thrombus such as organic thrombus, calcified thrombus and larger thrombus, so as to improve the second stent body. The net port 411b has the ability to capture hard thrombi, so that the hard thrombus can enter the channel 1010b inside the third stent body 40b from the second net port 411b to improve the efficiency of capturing hard thrombus.

It should be noted that the structural design of the bracket body 101b of the bolt removal bracket 100b of the fourth embodiment is applicable to the bolt removal bracket 100h in the second embodiment, and will not be repeated here.

Please refer to FIGS. 16 and 17 together. FIG. 16 shows a schematic structural diagram of a thrombus removal bracket 100d provided by a fifth embodiment of the present invention; Schematic diagram of the structure from one angle. In the fifth embodiment, the structure of the bolt removal bracket 100d is similar to the structure of the bolt removal bracket 100b of the fourth embodiment. The difference is that the capturing section 41d of the third bracket body 40d is different from the capturing section 41b of the third bracket body 40b in the second embodiment.

As shown in FIG. 16, the distal end of the second stent body 30d is completely open to form a first open end 301d. The third stent body 40d is connected between the second stent body 30d and the protective umbrella 6, the proximal end of the third stent body 40d forms a third open end 401d, the distal end of the third stent body 40d forms a fourth open end 403d, and the protective umbrella 6 The proximal end of the protective umbrella 6 forms an umbrella end 601, the distal end of the protective umbrella 6 forms a first closed end 603 directly opposite to the umbrella end 601, the first open end 301d and the third open end 401b, the fourth open end 403d and the umbrella end 601 is connected, so that a continuous channel 1010d is formed inside the bolt removal bracket 100d.

In this embodiment, the proximal end of each second network port 411d is not formed with a third capturing unit. The capturing section 41d does not include a skeleton rod, that is, the skeleton rod is replaced by another third mesh port 413d. Specifically, each capturing portion 43d includes a second mesh port 411d, and each reinforcing portion 44d of the capturing section 41d includes two third mesh ports 413b connected in parallel along a direction parallel to the central axis L of the bracket body 101d. Each capturing part 43d is roughly olive-shaped. Each reinforcing portion 44d is roughly in the shape of an "8". The capturing section 41d is formed by enclosing at least one second network port 411d and a plurality of third network ports 413d. The first network port 421d, the second network port 411d, and the third network port 413d are connected to each other to form a third bracket body 40d having a tubular structure or a cage structure.

The shape of the proximal and distal ends of the second network port 411d is the same as the shapes of the proximal and distal ends of the third network port 413d, so as to ensure the radial force balance of the capturing section 41d and the smoothness of the capturing section 41d, and Enhance the adhesion of the capture section 41d and increase the capture rate of thrombus. Two adjacent third network ports 413d. The shape of the third net port 413d is the same as the shape of the first net port 421d to ensure the flexibility of the stent body 101b, and to make the stent body 101b have a certain supporting force in the radial and axial directions, and to improve the support of the stent body 101b. The capture efficiency of thrombus.

In this embodiment, the second network port 411d is roughly olive-shaped. Each second network port 411d has a proximal connection point 4111d, and each proximal connection point 4111d of the capturing section 41d is connected to the distal end of the corresponding second support rod 352. In this way, the area of the second network port 411d is increased, thereby further improving the ability of the thrombus removal stent 100d to capture hard thrombi such as organizing thrombus, calcified thrombus, and larger thrombus.

The second network port 411d is directly opposite to the first closed-loop unit 311, that is, the second network port 411d is disposed between two adjacent second closed-loop units 331. The number of the second network port 411d is equal to the number of the first closed loop unit 311, thereby ensuring the axial and radial supporting force of the thrombus removal stent, while making it easier for thrombus to enter the third stent from the second network port 411d A channel 1010d inside the body 40d.

In this embodiment, the second mesh port 411d is not provided with a third capturing unit, and the second mesh port 411d is parallel to the stent body 101d on opposite sides of the central axis L respectively connected in parallel along the central axis L Two third network ports 413d, thereby increasing the area of the second network port 411d, so that thrombus enters the channel 1010d inside the third stent body 40d from the second network port 411d, and increasing the diameter of the second network port 411d The extended space in the direction increases the area of the second network port 411d and enhances the adhesion of the capturing section 41d.

The bolt removal bracket 100d provided by the embodiment of the present invention is provided with a third bracket body 40d, and the proximal end of the third bracket body 40d is provided with a second network port 411d with a larger network port area. Since the third capture unit is not formed at the proximal end of the second mesh port 411d, the area of the second mesh port 411d is increased to further increase the thrombus that the second mesh port 411d does not effectively capture the second stent body 30d. For example, the ability to capture hard thrombi such as organic thrombus, calcified thrombus and larger thrombus, and then the hard thrombus can enter the internal channel 1010d of the third stent body 40d from the second mesh port 411d to improve the resistance to hard thrombus Capture efficiency.

It should be noted that the structural design of the stent body 101d of the bolt removal stent 100d of the fifth embodiment is applicable to the bolt removal stent 100h of the second embodiment, and will not be repeated here.

Please refer to FIG. 18, which is a schematic structural diagram of a bolt removal system 1000 according to an embodiment of the present invention. The thrombus removal system 1000 includes the above-mentioned thrombus removal stent 2, a push rod 200 and a micro catheter 300. The thrombus removal stent 2 includes a thrombus removal stent 100 and a protective umbrella 6 arranged at the distal end of the thrombus removal stent 100. The push rod 200 is connected to the proximal end of the thrombus removal stent 100. The push rod 200, the thrombus removal stent 100 and the protective umbrella 6 are pressed and held. Lead into the micro catheter 300. The plug-removing bracket 100 and the protective umbrella 6 can move inside and outside the microcatheter 300 by pushing and pulling the push rod 200. When the push rod 200 moves toward the proximal end of the micro catheter 300, the stent 100 and the protective umbrella 6 are recovered into the micro catheter 300; when the push rod 200 moves away from the proximal end of the micro catheter 300, the removal The bolt holder 100 and the protective umbrella 6 are pushed out of the micro catheter 300.

In this embodiment, the connection between the proximal end of the bolt-removing bracket 2 and the distal end of the push rod 200 includes welding, sleeve connection, or fixed connection with glue. Optionally, welding includes, but is not limited to silver welding or gold welding. Adhesives include, but are not limited to UV glue or epoxy glue. The micro catheter 300 is sleeved outside the pushing rod 200. The bolt removal system 1000 further includes a loading tube 400. The loading tube 400 is used to fix the micro catheter 300.

When in use, the proximal end of the thrombus removal stent 100 and the distal end of the push rod 200 are first connected, and then the installed thrombus removal stent 2 and the push rod 200 are compressed into the microcatheter 300 in advance. During the interventional treatment, the microcatheter 300 is delivered to the diseased part of the blood vessel, and passes through the thrombus to fix the microcatheter 300. Push the thrombus removal stent 2 through the push rod 200 to the position of the thrombus determined according to the imaging positioning element 102, and withdraw the microcatheter 300 to release the embolization stent 2 at the distal end of the microcatheter 300, and the embolization stent 2 bounces at the distal end The vessel wall is anchored, and then the push rod 200 is slowly pushed forward, and the micro-catheter 300 is retracted under the reaction force at the same time to release the tension of the micro-catheter 300, repeating several times until the embolization stent 2 is completely released.

Since the bolt removal stent 2 is made of a shape memory material, the bolt removal stent 2 has elasticity, so that the bolt removal stent 2 can be switched between a compressed state and a released state. By releasing the thrombus removal stent 2, the thrombus removal stent 2 can be completely embedded inside the thrombus. After waiting for a certain period of time, the push rod 200 is pulled back, and the thrombus removal stent 2 is retracted to capture the thrombus, until the thrombus removal stent 2 together with the microcatheter 300 are retracted and withdrawn from the body, and the entire thrombus removal process is completed. The embolization stent 1000 as a whole is crimped and introduced into the microcatheter 300, that is, the embolization stent 2 is delivered to the diseased part of the blood vessel through the microcatheter 300.

It should be noted that the

bolt removal brackets

100h, 100a, 100b, and 100d in the second embodiment to the fifth embodiment can all be applied to the bolt removal system, which will not be repeated here.

The thrombus removal stent and thrombus removal system provided by the embodiments of the present invention are based on the provision of a protective umbrella at the distal end of the thrombus removal stent, thereby effectively preventing the thrombus detached from the stent body from escaping. In addition, the distal end of the stent body forms a first open end, the proximal end of the protective umbrella forms an umbrella end opposite to the first open end, and the distal end of the protective umbrella forms a first open end opposite to the umbrella end. Sealing end, the umbrella mouth end is connected with the first opening end, so that a continuous channel is formed inside the bolt removal bracket. In this way, the thrombus detached from the stent body completely enters the protective umbrella without being blocked, so that the protective umbrella can effectively recover the thrombus detached from the stent body, thereby avoiding the problem of blood vessel re-embolism caused by the thrombus detaching from the stent body, and preventing the removal of the thrombus. Complications caused by embolization treatment, thereby increasing the recanalization rate of blood vessels. In addition, because the mouth end of the umbrella is connected to the first open end, that is, the protective umbrella is close to the distal end of the stent body, thereby preventing thrombus from escaping, and the protective umbrella is released synchronously with the stent body, so the protective umbrella can The protective umbrella is quickly opened by the radial support force of the stent body until the protective umbrella is unfolded to a predetermined state, so as to contain the thrombus falling off from the stent body.

The embodiments of the present invention are described in detail above, and specific examples are used in this article to illustrate the principles and embodiments of the present invention. The descriptions of the above embodiments are only used to help understand the methods and core ideas of the present invention; at the same time, for Those skilled in the art, based on the idea of the present invention, will have changes in specific embodiments and application ranges. In summary, the content of this specification should not be construed as limiting the present invention.

Claims

A plug-removing stent includes a stent body and a protective umbrella arranged at the distal end of the stent body. The distal end of the stent body forms a first open end, and the proximal end of the protective umbrella is formed to be directly opposite to the first open end The end of the umbrella, the distal end of the protective umbrella forms a sealed end that is opposite to the end of the umbrella, and the end of the umbrella is connected with the first open end, so that the inside of the plug-removing bracket forms a continuous aisle.
The bolt removal bracket according to claim 1, wherein a peripheral edge of the first open end is provided with a mounting structure, and a peripheral edge of the umbrella mouth end is provided with a connecting structure matingly connected with the mounting structure.
The bolt-removing bracket of claim 2, further comprising a connecting member, and the mounting structure is connected to the connecting structure through the connecting member, so that the umbrella mouth end and the first open end Connected.
The bolt removal bracket of claim 3, wherein the first open end forms a first bending portion that is continuously bent, and the mounting structure is disposed on the first bending portion, and the The umbrella mouth end forms a second bending portion that is continuously bent, and the connecting structure is disposed on the second bending portion.
4. The bolt removal stent according to claim 4, wherein the first open end is formed by a plurality of first mesh openings, and the distal end of each of the first mesh openings is configured as a first bending structure, A plurality of the first bending structures are connected to each other to form the first bending portion; the umbrella mouth end is formed by a plurality of first mesh units, and the proximal end of each first mesh unit is configured as A second bending structure, a plurality of the second bending structures are connected to each other to form the second bending portion.
The bolt removal bracket of claim 5, wherein the number of the plurality of first network ports is less than the number of the plurality of first grid units, and the area of each of the first network ports is Larger than the area of each of the first grid cells.
The bolt removal bracket of claim 5, wherein the mounting structure is formed by a plurality of connecting pieces having connecting holes, and the plurality of connecting pieces are respectively arranged on the plurality of the first bending structures , The connecting structure is formed by the plurality of connecting buckles, each of the connecting buckles is arranged on the corresponding second bending structure, the connecting piece is configured as a connecting ring, and the connecting ring passes through each A connecting hole of the connecting piece and the plurality of connecting buckles are used to connect the protective umbrella and the bracket body.
The bolt removal bracket of claim 7, wherein the number of the connecting buckles is more than the number of the connecting holes, and each of the connecting buckles is correspondingly disposed on each of the second bending structures .
The bolt-removing bracket according to claim 7, wherein the number of the connecting buckles is equal to the number of the connecting holes, and each of the connecting buckles is arranged on the second bending structure corresponding to the connecting hole. Location.
The bolt removal bracket of claim 7, wherein the protective umbrella comprises a mesh body formed by interlacing a plurality of ribs, each rib is structured in a petal structure and distributed radially, and each The proximal end of the umbrella rib protrudes outward relative to the net body to form the second bending structure.
9. The bolt removing bracket of claim 10, wherein the middle part of each rib crosses to form the corresponding connecting buckle.
9. The plug-removing stent according to claim 10, wherein the net body includes a cylindrical extension part and a conical recovery part, and the extension part is disposed between the stent body and the recovery part, The plurality of connecting buckles are arranged at the proximal end of the extension part.
The bolt removal bracket according to claim 12, wherein the extension part is formed by a combination of the plurality of first grid units and a plurality of second grid units, and the recovery part is formed by a plurality of The area of the plurality of second grid units is the same, the area of the plurality of third grid units gradually increases from the distal end to the proximal end, and the second grid unit The area of is larger than the area of the third grid unit and smaller than the area of the first network port.
The bolt-removing bracket of claim 5, wherein the mounting structure is formed by a plurality of fixing rods, and the plurality of fixing rods are respectively arranged on the plurality of first bending structures, and the connection The structure is enclosed by a plurality of connecting rods, the plurality of connecting rods are dispersedly arranged on the corresponding second bending structure, and each of the connecting rods is adjacent to the corresponding fixed rod, and the connecting rods The member is configured as a connecting wire, and the connecting wire is wound around the adjacent fixing rod and the connecting rod to connect the protective umbrella and the bracket body.
The plug-removing bracket according to claim 14, wherein the connecting wire is a developing positioning element.
The bolt removal bracket according to claim 14, wherein the connecting rod includes a plurality of bent sections and a straight section, and the straight section extends from the plurality of bent sections to the straight section. Convergent weave formation.
The bolt removal stent according to claim 16, wherein the distal end of each bending section is connected to the middle of the corresponding second bending structure, and the plurality of bending sections surround the flat section. The straight sections are centrally symmetrically distributed, and the straight sections are arranged outside the junction of two adjacent second bending structures.
The bolt removing bracket according to claim 16, wherein the straight sections of the fixing rod and the connecting rod both extend in a direction parallel to the central axis of the bolt removing bracket.
The bolt removal stent according to claim 1, wherein the maximum outer diameter of the protective umbrella is greater than or equal to the maximum outer diameter of the bolt removal stent, and the umbrella mouth end is on the upper edge of the first open end. The axial orthographic projection coincides with the first open end.
The thrombus removal stent according to claim 1, wherein the stent body includes a first stent body and a second stent body disposed at the distal end of the first stent body, and the second stent body includes a large Pipe diameter section, small pipe diameter section and transition section, the large pipe diameter section and the small pipe diameter section are alternately connected, and the large pipe diameter section and the small pipe diameter section are connected by the transition section, The plug-removing stent has a semi-free state and a free state. In the semi-free state, at least part of the structure of the second stent body is approximately a single-layer tubular structure; in the free state, the second stent The body has an approximate double-layer tubular structure.
The bolt removal stent according to claim 20, wherein the bolt removal stent further comprises a third stent body, the third stent body is connected between the second stent body and the protective umbrella, the The proximal end of the third stent body forms a third open end, the distal end of the third stent body forms a fourth open end, the first open end and the third open end, the fourth open end, and the The end of the umbrella mouth is connected, so that a continuous channel is formed inside the bolt-removing bracket.
The plug-removing stent according to claim 21, wherein the third stent body includes a capturing section and an extension section connecting the capturing section and the protective umbrella, and the proximal end of the capturing section passes through the The transition section is connected to the small tube diameter section of the second stent body, and the distal end of the capture section is connected to the proximal end of the extension section.
The bolt removal stent according to claim 22, wherein the capturing section includes at least one capturing portion and a plurality of reinforcing portions, and the at least one capturing portion and the plurality of reinforcing portions extend along the circumference of the third stent body. They are connected side by side, and the shape of the capturing part is different from the shape of the reinforcing part.
The bolt removal stent according to claim 23, wherein the large pipe diameter section includes a plurality of first closed loop units connected to each other, and the small pipe diameter section includes a plurality of second closed loop units connected to each other. The extension section includes a plurality of first mesh ports connected to each other; each of the capturing parts includes a second mesh port, and each of the reinforcing parts includes a third mesh port and a skeleton arranged at the proximal end of the third mesh port Rod, or each reinforcing part includes a plurality of third network ports connected in parallel along the direction parallel to the central axis of the bracket body, wherein the area of the second network port is larger than that of the first network port and the For the areas of the first closed-loop unit and the second closed-loop unit, the area of the third network port is equal to the area of the first network port and the area of the first closed-loop unit.
The thrombus removal stent according to claim 24, wherein the distal end of the first closed loop unit forms a first capture unit, and the distal end of the second closed loop unit forms a second capture unit, and each A third catching unit is formed at the proximal end of the second mesh opening, and the first catching unit, the second catching unit, and the third catching unit are all outwardly or towards the stent body. It extends inside and forms a corresponding first accommodating space, a second accommodating space and a third accommodating space between the bracket body.
A thrombus removal system, characterized in that it comprises a push rod, a microcatheter, and the thrombus removal stent according to any one of claims 1-25, the thrombus removal stent includes a stent body and a stent body provided on the stent body The distal end of the protective umbrella, the push rod is connected to the proximal end of the stent body, the push rod, the stent body and the protective umbrella are crimped into the micro catheter, the stent body and the protective umbrella The push rod can be pushed and pulled to move inside and outside the micro catheter. When the push rod moves toward the proximal end of the micro catheter, the stent body and the protective umbrella are recovered to the micro catheter. In the catheter; when the push rod moves away from the proximal end of the micro catheter, the stent body and the protective umbrella are pushed out of the micro catheter.