CN114027928B

CN114027928B - Thrombectomy support, thrombectomy device and thrombectomy system

Info

Publication number: CN114027928B
Application number: CN202210019201.0A
Authority: CN
Inventors: 王永胜; 于鹏; 郭亚萍
Original assignee: Hangzhou Deno Brain Neurology Medical Technology Co ltd
Current assignee: Hangzhou Deno Brain Neurology Medical Technology Co ltd
Priority date: 2022-01-10
Filing date: 2022-01-10
Publication date: 2022-03-29
Anticipated expiration: 2042-01-10
Also published as: CN114027928A; WO2023131311A2; WO2023131311A3

Abstract

The invention relates to a thrombus taking support, a thrombus taking device and a thrombus taking system, wherein the thrombus taking support comprises a first support body and a second support body: the second bracket body is arranged at the far end of the first bracket body; the second stent body comprises a first pipe diameter section and a transition section; the first pipe diameter sections and the transition sections are alternately arranged along the axial direction of the bolt taking bracket, and two adjacent first pipe diameter sections are connected through the transition sections; when the proximal end and the distal end of the embolectomy support are relatively far away from each other along the axial direction, at least partial areas of the first pipe diameter sections are radially contracted, and the radially contracted areas of the two axially adjacent first pipe diameter sections form an included angle. When the thrombus is captured in the blood vessel and pulled, the thrombus taking support can maintain the appearance in different directions, the whole thrombus taking support cannot be obviously collapsed, and the thrombus taking support capable of maintaining the appearance in different directions can increase the resistance of thrombus escape, so that the thrombus in different directions can be effectively captured, and the risk of thrombus escape is reduced.

Description

Thrombectomy support, thrombectomy device and thrombectomy system

Technical Field

The invention relates to the technical field of medical instruments, in particular to a thrombus taking support, a thrombus taking device and a thrombus taking system.

Background

Thrombus is formed by abnormal aggregation of blood platelet and other tangible components in blood in circulating blood, and the blood clot is generated on the inner wall or the blood vessel wall of a heart to cause blood vessel blockage or embolism and secondary serious body injury. The thrombus formation is distributed throughout the cardiovascular system, spreads to tissues and organs of the whole body, is not limited to the pathological changes of myocardial infarction, deep venous thrombosis or cerebrovascular thrombosis and the like, and can occur in blood vessels of any part in the body. The incidence rate of venous thrombosis is higher than that of arterial thrombosis, the ratio of the venous thrombosis to the arterial thrombosis can reach 4: 1, the venous thrombosis accounts for 40% -60% of a thrombosis mechanism, the incidence rate of the thrombosis of the blocked coronary artery is 15% -95%, and 90% of thrombosis is accompanied by atherosclerotic plaques. Thrombosis causes vessel occlusion, and blood flow blockage causes related vessel domination tissue ischemia, anoxia and even necrosis to generate corresponding tissue and organ dysfunction symptoms.

At present, anticoagulant drugs and thrombolytic drugs are mostly adopted for treatment in clinic, but the treatment effect is extremely poor, the larger the diameter of a thrombus-blocked blood vessel is, the poorer the treatment effect is, the lower the blood vessel recanalization rate is, the longer the recanalization time is, and some patients are not suitable for thrombolytic treatment.

At present, some mechanical devices are adopted for thrombus removal, a novel and efficient blood vessel recanalization treatment method is provided for thrombus patients, mechanical thrombus removal operation time is short, related complications are few, and the mechanical thrombus removal device is a research hotspot in the field of thrombus treatment at present; according to the shape and function realization form of the mainstream interventional embolectomy device, the mainstream interventional embolectomy device can be divided into the following parts: spiral, screen type, brush type, suction type, stent type. The common defects of the mainstream products are that the structure is easy to deform and collapse when the blood vessel is bent, and the thrombus is easy to fall off at the bent blood vessel when the blood vessel is withdrawn, so that the thrombus escapes and the blood vessel is damaged to different degrees. Nerve thrombus takes internal carotid artery, middle cerebral artery, vertebral artery and basilar artery as the good part, the state of acute thrombus is mostly greasy and smooth state, and the existing metal thrombus taking bracket is difficult to capture completely.

Disclosure of Invention

The invention aims to provide an embolectomy support, which is used for optimizing the structure of the embolectomy support in the embolectomy device in the prior art and improving the thrombus capture performance of the embolectomy support.

Another object of the present invention is to provide an embolectomy device, so as to optimize the structure of the embolectomy device in the prior art and improve the thrombus capture performance of the embolectomy device.

It is still another object of the present invention to provide an embolectomy system that optimizes the structure of prior art embolectomy systems and improves the thrombus capture performance of the embolectomy system.

In order to solve the technical problems, the invention adopts the following technical scheme:

according to one aspect of the invention, there is provided a embolectomy support comprising a first support body and a second support body; the second stent body is arranged at the far end of the first stent body; the second stent body comprises a first pipe diameter section and a transition section; the first pipe diameter sections and the transition sections are alternately arranged along the axial direction of the bolt taking support, and two adjacent first pipe diameter sections are connected through the transition sections; when the proximal end and the distal end of the embolectomy support are relatively far away from each other along the axial direction, at least partial areas of the first pipe diameter sections are radially contracted, and two areas of the first pipe diameter sections, which are adjacent to each other in the axial direction, radially contracted are arranged at included angles.

According to another aspect of the invention, the invention also provides an embolectomy device, which comprises the embolectomy bracket and a traction guide wire connected with the embolectomy bracket; the traction guide wire is connected with the proximal end of the thrombus removal support and used for pushing and pulling the thrombus removal support.

According to another aspect of the invention, the invention also provides an embolectomy system, which comprises the embolectomy device, a push rod, a loading sheath and a micro-catheter; the push rod is connected with the near end of the thrombus taking support and is used for pushing and pulling the thrombus taking support; the loading sheath is used for accommodating the embolectomy device in a compressed state; the micro-catheter is used for being communicated with the loading sheath, and the lumen in the micro-catheter is used for conveying the thrombus removal device.

According to the technical scheme, the embodiment of the invention at least has the following advantages and positive effects:

in the thrombus taking support provided by the embodiment of the invention, the first pipe diameter sections can adapt to blood vessels with different diameters, so that the adherence performance with the blood vessels is ensured, on the basis, when the near end and the far end of the thrombus taking support are relatively far away from each other along the axial direction, two axially adjacent first pipe diameter sections are arranged in an included angle in a radially contracted area, namely, the two axially adjacent first pipe diameter sections are different in radially contracted part, the radially contracted area is staggered, so that the radially uncollapsed area is also staggered, which means that when the thrombus taking support is pulled after capturing thrombus in the blood vessels, the thrombus taking support can maintain the shape in different directions, the whole thrombus taking support cannot be obviously collapsed, the thrombus taking support capable of maintaining the shape in different directions can increase the escape resistance of thrombus, and the thrombus taking support can still maintain the contact area with the thrombus in the blood vessels with different bending degrees, therefore, thrombi in different directions can be effectively caught, and the risk of escape of the thrombi is reduced.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the structures shown in the drawings without creative efforts.

FIG. 1 is a schematic structural diagram of a thrombus removal device according to an embodiment of the present invention;

FIG. 2 is a schematic structural view of the embolectomy device shown in FIG. 1 after being relatively deflected by 90 degrees in the circumferential direction;

FIG. 3 is a schematic view of the thrombectomy stent shown in FIG. 1, shown in an axially tensioned state;

FIG. 4 is a schematic view of the thrombectomy stent of FIG. 2 shown in an axially tensioned state;

FIG. 5 is a schematic cross-sectional view taken along section line II-II of FIG. 1;

FIG. 6 is a schematic cross-sectional view along section line III-III in FIG. 1;

FIG. 7 is an enlarged schematic view of the thrombectomy device shown in FIG. 1 at A;

FIG. 8 is a schematic view of the pull wire of FIG. 1 attached to the proximal end of the thrombectomy stent;

FIG. 9 is a schematic structural view of another embodiment of a pull wire coupled to the proximal end of an embolectomy stent;

FIG. 10 is a schematic structural view of yet another embodiment of a pull wire coupled to the proximal end of an embolectomy stent;

FIG. 11 is a schematic view of the visualization guidewire of FIG. 1 attached to the distal end of the thrombectomy stent;

FIG. 12 is a schematic structural view of the embolectomy device of FIG. 1 prior to assembly for use;

FIG. 13 is a schematic view of the thrombectomy device of FIG. 12 in an assembled configuration;

FIG. 14 is a schematic view of the thrombectomy device of FIG. 13 in a deployed state in the microcatheter;

FIG. 15 is a schematic diagram of a first state of the embolectomy device of FIG. 1 during embolectomy;

FIG. 16 is a schematic diagram of a second state of the embolectomy device of FIG. 1 during embolectomy;

FIG. 17 is a schematic diagram of a third state of the embolectomy device in FIG. 1 during embolectomy;

FIG. 18 is a schematic diagram illustrating a fourth state of a bolt-removing process of the bolt-removing device shown in FIG. 1;

FIG. 19 is a schematic diagram illustrating a fifth state of the embolectomy device of FIG. 1 during embolectomy;

FIG. 20 is a schematic view of the thrombectomy device shown in FIG. 19, showing another perspective view of the fifth state of the thrombectomy device.

The reference numerals are explained below:

01. thrombosis; 100. a thrombus taking device; 200. a push rod; 300. loading a sheath; 400. a microcatheter; 500. a sheath tube; 600. a joint member; 700. perforating a guide wire;

1. a thrombus taking support; 101. a first mesh; 102. a second mesh; 102a, a network port; 103. a third mesh; 104. a fourth mesh; 105. a fifth mesh; 106. a skeletal frame rod; 1061. a first reinforcement bar; 1062. a second reinforcement bar;

11. a first bracket body;

12. a second stent body; 121. a first pipe diameter section; 121a, a first capturing unit; 121b, a first accommodating space; 12a, a first area; 12b, a second region; 12c, a third area; 12d, a fourth area; 1211. a first wave bar; 1211a (1211 c), a proximal vertex; 1211b (1211 d), distal vertex; 122. a transition section; 123. a first support bar; 124. a second support bar; 125. a second pipe diameter section; 125a, a second capturing unit; 125b, a second accommodating space; 1251. a second wave shaped lever; 1251a (1251 c), proximal vertex; 1251b (1251 d), distal vertex; 126. a support arm;

13. a third stent body; 131. a capturing section; 1311. a reinforcing portion; 132. an extension section; 1321. a third waveform rod; 103a, a third capturing unit;

14. a proximal end connector; 141. a first windowing;

15. a distal connector; 151. second windowing;

16. developing the guide wire;

2. drawing a guide wire; 21. and fixing the head.

Detailed Description

Exemplary embodiments that embody features and advantages of the invention are described in detail below in the specification. It is to be understood that the invention is capable of other embodiments and that various changes in form and details may be made therein without departing from the scope of the invention and the description and drawings are to be regarded as illustrative in nature and not as restrictive.

In the description of the present application, it is to be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the present application and for simplicity in description, and are not intended to indicate or imply that the referenced devices or elements must have a particular orientation, be constructed in a particular orientation, and be operated in a particular manner, and are not to be construed as limiting the present application.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", may explicitly or implicitly include one or more of the described features. In the description of the present application, "a plurality" means two or more unless specifically limited otherwise.

In the description of the present application, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present application can be understood in a specific case by those of ordinary skill in the art.

For ease of description and understanding, it is defined herein that "proximal" refers to the end closer to the operator and "distal" refers to the end further from the operator. In particular, proximal end refers to the end that is intended for operation by a user or machine or for connection to other devices. Distal end refers to the end of the instrument that is freely insertable into the body of an animal or human.

The thrombus taking support and the thrombus taking device provided by the embodiment of the invention are used for dredging the blocked blood vessel and catching thrombus in the blocked blood vessel when the blood vessel is blocked. The thrombus removal device comprises a thrombus removal support and a traction guide wire, wherein the traction guide wire is connected with the thrombus removal support and can be arranged in the thrombus removal support in a penetrating manner. The thrombectomy stent has radial scalability, so that the thrombectomy stent has a collapsing state and a natural expansion state. In the collapsed state, the thrombus taking stent can be conveniently delivered in a blood vessel through a microcatheter and delivered to a diseased region. When the thrombus reaches the pathological change part, the microcatheter is withdrawn, so that the thrombus taking support can recover the natural expansion state, the thrombus at the pathological change part is cut and captured, and finally the captured thrombus is withdrawn, thereby realizing the dredging of the blocked blood vessel.

Referring first to fig. 1, the thrombectomy device 100 of the present embodiment includes a thrombectomy support 1 and a pull wire 2.

The thrombus taking support 1 is of a hollow tubular structure, the peripheral wall of the thrombus taking support can be of a grid or mesh structure, and the grid or mesh structure can be of a regular or irregular hole structure. The traction guide wire 2 passes through the proximal end of the thrombectomy stent 1 and is connected with the proximal end of the thrombectomy stent 1. The near end of the traction guide wire 2 can be connected with the outside, and the thrombus removal support 1 can be driven to withdraw towards the near end of the blood vessel by the traction guide wire 2 moving towards the near end of the blood vessel.

The thrombectomy stent 1 has a collapsed state and a natural expanded state. In the collapsed state, the radial dimension of the stent 1 is minimized to facilitate delivery within a vessel for delivery of the stent 1 to a lesion site.

The stent 1 may be made of a memory metal material or a polymer material with elasticity, for example, so that the stent 1 is released into the blood vessel to self-expand to form a tubular and/or cage-like structure. Specifically, the nickel-titanium composite material can be formed by weaving or laser cutting a nickel-titanium pipe, can also be formed by laser cutting a nickel-titanium plate and then curling and heat setting, can be further formed by weaving a nickel-titanium wire material, and can also be formed by processing an elastic plastic material. When the thrombectomy stent 1 is released to the blood vessel and no external pressure exists in the radial direction, the thrombectomy stent 1 expands automatically and the radial size becomes larger. In the natural expansion state, the thrombectomy stent 1 props up the thrombus at the lesion site, and cuts the thrombus by using the grid or mesh structure on the outer peripheral wall of the thrombectomy stent 1, so that the thrombus enters the thrombectomy stent 1 and is captured by the thrombectomy stent 1. Along with the traction of the guide wire 2 to the near end of the blood vessel, the controllable thrombus preparation stent 1 drives the thrombus captured in the controllable thrombus preparation stent to withdraw, and the blocked blood vessel is dredged.

Referring to fig. 1 and 2, the embolectomy stent 1 includes a first stent body 11 and a second stent body 12. The proximal end of the first stent body 11 is connected with the distal end of the traction guide wire 2, the distal end of the first stent body 11 is connected with the proximal end of the second stent body 12, and the first stent body 11 and the second stent body 12 are connected to form a tubular structure for capturing thrombus. When the embolectomy stent 1 is withdrawn, the pull wire 2 can more easily withdraw the second stent body 12 together into the microcatheter through the first stent body 11.

The second stent body 12 comprises first diameter sections 121 and transition sections 122, the first diameter sections 121 and the transition sections 122 are alternately arranged along the axial direction of the embolectomy stent 1, and two adjacent first diameter sections 121 are connected through the transition sections 122. When the proximal end and the distal end of the thrombectomy stent 1 are relatively far away in the axial direction, that is, when the proximal end of the thrombectomy stent 1 is pulled back by a pulling force, at least a partial region of the first diameter section 121 is radially contracted, and the radially contracted regions of two axially adjacent first diameter sections 121 form an included angle.

For more detailed description, please refer to fig. 1 and 3, or fig. 2 and 4, in which fig. 1 and 2 are schematic views of the state of the embolectomy stent 1 in two different viewing orientations before the proximal end of the embolectomy stent is pulled, and also can be understood as a schematic view of the state of the embolectomy stent 1 fully expanded freely after being released into a blood vessel, in which the radial dimensions of the regions of the first diameter section 121 are approximately equal, the radial dimensions of the first diameter section 121 in all directions are not obviously different, two adjacent first diameter sections are relatively displaced in the circumferential direction, and two adjacent transition sections are relatively displaced in the circumferential direction. Fig. 3 and 4 are schematic views of the thrombectomy stent 1 illustrated in fig. 1 and 2 in two different viewing orientations after the proximal end of the thrombectomy stent 1 is pulled, which can also be understood as a schematic view of the thrombectomy stent 1 with captured thrombi, in which at least a partial region of each first diameter section 121 is significantly radially contracted, i.e. radially collapsed. In addition, the radial contracted areas of the two first diameter sections 121 adjacent to each other in the axial direction also present a certain included angle, which means that the areas which are not collapsed or the areas with relatively small collapse amplitude also present a certain included angle.

In the present embodiment, when the proximal end and the distal end of the embolectomy stent 1 are relatively far away in the axial direction, the radially contracted regions of the two axially adjacent first diameter sections 121 are relatively displaced in the circumferential direction, for example, the relative displacement angle is 90 degrees, which can be understood as that the regions with no significant change in the radial dimension are also displaced by 90 degrees. The structure of the thrombus alternately staggered along the axial direction of the thrombus taking support 1 enables the thrombus taking support 1 to catch thrombus more easily. It is understood that in other embodiments, the angle of the misalignment may also assume other angle settings, which are not limited in this application, and for the sake of understanding, this application will exemplify the misalignment of 90 degrees.

With reference to fig. 5 and 6, fig. 5 and 6 are schematic cross-sectional views of two adjacent first diameter sections 121, the first diameter sections 121 have a first region 12a and a second region 12b which are arranged opposite to each other in the radial direction, and a third region 12c and a fourth region 12d which are arranged opposite to each other, and the first region 12a, the third region 12c, the second region 12b, and the fourth region 12d are sequentially arranged in the circumferential direction of the second stent body 12. It should be noted that the "area" may include at least one of a point, a line, and a plane. When the proximal end and the distal end of the embolectomy stent 1 are relatively far away along the axial direction, the first area 12a and the second area 12b contract radially, the third area 12c and the fourth area 12d maintain the radial dimension unchanged, or the radial contraction dimension of the third area 12c and the fourth area 12d is smaller than that of the first area 12a and/or smaller than that of the second area 12 b. In this embodiment, the first region 12a and the second region 12b may be understood as a plane, and the third region 12c and the fourth region 12d may be understood as a point or a line, that is, the third region 12c and the fourth region 12d are a point where the first region 12a intersects with the second region 12b or a line where the first region 12a intersects with the second region 12 b.

When the first diameter section 121 contracts radially, the radial dimension of the radial contraction area of the first diameter section 121 is small in the middle and large at the two ends in the circumferential direction. That is, after the first area 12a and the second area 12b are radially contracted, the radial dimension of the first area 12a and the radial dimension of the second area 12b are gradually increased from the center thereof toward both sides until they are equal to the radial dimensions of the third area 12c and the fourth area 12 d.

The above contraction law of the regions can be understood that, in two axially adjacent first diameter sections 121 (fig. 5 and 6), the first region 12a and the second region 12b of the two first diameter sections 121 are simultaneously offset in the circumferential direction by an angle equal to the included angle of the offset of the radially contracted regions of the two first diameter sections 121, for example, the offset angle is 90 degrees. Moreover, the third region 12c and the fourth region 12d of the two first diameter sections 121 are also circumferentially displaced by an angle equal to the angle at which the radially contracted regions of the two first diameter sections 121 are displaced, for example, by 90 degrees.

When the embolectomy stent 1 is withdrawn by using the traction guide wire 2, the proximal end of the embolectomy stent 1 is subjected to a traction force, and a partial area of the first pipe diameter section 121 is radially contracted, namely, radially collapsed. This may be manifested as the first and

second regions

12a, 12b radially collapsing as described above, with the third and

fourth regions

12c, 12d maintaining the radial dimension within a predetermined range. Thus, even when the blood vessel is excessively bent during the process of withdrawing the thrombus stent 1, the adherence performance of the third region 12c and the fourth region 12d to the blood vessel can be always maintained, and the third region 12c and the fourth region 12d which are axially adjacent are arranged at a position shifted by 90 degrees in the circumferential direction, so that the passage for the thrombus caught by the thrombus stent 1 to escape is not smooth, the resistance is increased, and the thrombus is difficult to escape.

According to the thrombus taking stent 1 provided by the embodiment of the invention, the first tube diameter sections 121 can adapt to blood vessels with different diameters, and the adherence performance with the blood vessels is ensured, on the basis, when the near end and the far end of the thrombus taking stent 1 are relatively far away from each other along the axial direction, two axially adjacent first tube diameter sections 121 are arranged in an included angle in a radially contracted area, that is, the radially contracted areas of the two axially adjacent first tube diameter sections 121 are different in radially contracted position, and are staggered, so that it can be understood that the radially uncollapsed areas are also staggered, which means that when the thrombus taking stent 1 is pulled after capturing thrombus in a blood vessel, the thrombus taking stent 1 can maintain the shape in different directions through the undeformed areas of the first tube diameter sections 121, so that the radial supporting force is improved, the whole thrombus taking stent 1 cannot collapse obviously, and the thrombus escaping resistance of the thrombus taking stent 1 capable of maintaining the shape in different directions is increased, and the thrombus taking support 1 still keeps the contact area with the thrombus in the blood vessels with different bending degrees, so that the thrombus in different directions can be effectively captured, and the risk of thrombus escape is reduced.

In one embodiment, referring to fig. 1 and 7, the transition section 122 includes a first support rod 123 and a second support rod 124 spaced along the circumference of the second stent body 12, and the first support rod 123 and the second support rod 124 extend along the axial direction of the embolectomy stent 1 and are disposed between the proximal ends and the distal ends of two adjacent first diameter sections 121. For the purpose of the present invention, the first support bar 123 and the second support bar 124 may be used not only as an intermediate connecting member for two adjacent first diameter sections 121, but also to drive at least a partial region of the first diameter section 121 at one end to be radially deformed.

Two transition sections 122 adjacent in the axial direction are relatively staggered in the circumferential direction, two first pipe diameter sections 121 adjacent in the axial direction are relatively staggered in the circumferential direction, and the angle of relative displacement of the two first pipe diameter sections 121 adjacent in the circumferential direction is equal to the angle of relative displacement of the two transition sections 122 adjacent in the circumferential direction. This means that the two axially adjacent first support bars 123 are circumferentially offset by the same angle as the two axially adjacent first diameter sections 121. In this embodiment, the first supporting rod 123 and the second supporting rod 124 are circumferentially spaced by 180 degrees, and two axially adjacent first supporting rods 123 and two axially adjacent second supporting rods 124 are circumferentially staggered by 90 degrees.

In this embodiment, the first diameter section 121 includes a plurality of first wave-shaped rods 1211, the plurality of first wave-shaped rods 1211 are sequentially connected end to end along the axial direction of the embolectomy stent 1, and two adjacent first wave-shaped rods 1211 form a plurality of first mesh holes 101 arranged circumferentially, in this embodiment, the first mesh holes 101 are in a diamond structure, but in other embodiments, the first mesh holes 101 may also be in a mesh structure with other shapes, such as a triangle, a rectangle, a polygon, and the like, which is not limited in this application. For the sake of understanding, fig. 1 and 7 schematically list that the first diameter section 121 has two first wave bars 1211, and each first wave bar 1211 may be regarded as a closed loop structure formed by continuously bending and extending rod members in a Z-shape or a W-shape.

The first wave bars 1211 can be extended and contracted in a radial direction such that adjacent peaks and adjacent valleys between the respective first wave bars 1211 can be close to or apart from each other. At the time of natural expansion, the diameter of the first wavy rod 1211 becomes large, and the axial interval between the crests and the troughs becomes small while the circumferential interval becomes large. When the thrombus taking support 1 reaches the thrombus part of the lesion part, the first wave-shaped rod 1211 expands by itself to expand and can prop open the thrombus, and a blood flow channel is established to realize the function of pre-communicating; and the thrombus is cut by the first wave-shaped rod 1211, and the cut thrombus portion enters the first wave-shaped rod 1211 to be captured by the first mesh 101.

The proximal ends of the first support rod 123 and the second support rod 124 are connected to the proximal end of the first corrugated pipe 1211 adjacent to the proximal end of the first pipe diameter section 121, for example, to the proximal end of the first corrugated pipe 1211, and the distal end of the first corrugated pipe 1211 can be freely suspended to hook the thrombus. The distal ends of the first support bar 123 and the second support bar 124 are connected to the proximal apices of the first corrugated bars 1211 at the distal end adjacent to the first diameter section 121, such as the proximal apices of the first corrugated bars 1211.

One of the adjacent two first diameter sections 121 is defined as a proximal first diameter section 121, and the other is defined as a distal first diameter section 121. In fact, to achieve the above purpose, it is possible to connect the proximal end of the transition section 122 with a part of the vertex of the proximal first diameter section 121 while leaving a part of the free end point, and connect the distal end of the transition section 122 with the vertex of the distal first diameter section 121 without leaving the free end point of the distal first diameter section 121. Thus, when the embolectomy stent 1 is subjected to an axial pulling force, the nonuniformity of radial stress of the first pipe diameter section 121 at the proximal end of the transition section 122 can be ensured, so that the radial contraction of a partial area of the proximal first pipe diameter section 121 is realized, and the radial contraction of another partial area is not approximately generated. And simultaneously, the radial force uniformity of the proximal end of the distal first diameter section 121 is ensured, and the radial force uniformity of the proximal end of the distal first diameter section 121 can provide a supporting force for the distal first diameter section 121 to ensure that it radially contracts in a local area under the action of the next dislocated transition section 122.

Referring to fig. 1 and 7, in an embodiment, the transition section 122 further includes a second diameter section 125 and a plurality of supporting arms 126, the plurality of supporting arms 126 are arranged at intervals along the circumference of the second stent body 12, the proximal end of the second diameter section 125 is connected to the first supporting rod 123 and the distal end of the second supporting rod 124, and the distal end of the second diameter section 125 is connected to the proximal end of the first diameter section 121 through the plurality of supporting arms 126. To facilitate differentiation, in the naturally expanded state, the first diameter section 121 has a larger radial dimension than the second diameter section 125. The second pipe diameter section 125 not only ensures the flexibility of the thrombus removal support 1, but also ensures that the thrombus removal support 1 has certain supporting force in the radial direction and the axial direction, and simultaneously improves the capturing efficiency of the thrombus removal support 1.

In this embodiment, the second diameter section 125 includes a plurality of second wave bars 1251, the plurality of second wave bars 1251 are sequentially connected end to end along the axial direction of the embolectomy stent 1, and two adjacent second wave bars 1251 form a plurality of second mesh openings 102 arranged circumferentially. In this embodiment, the shape of second mesh openings 102 is a diamond-shaped structure, but in other embodiments, second mesh openings 102 may also be mesh openings with other shapes, such as triangular, rectangular, or polygonal, for example, and the application is not limited thereto. For ease of understanding, fig. 1 and 7 schematically list the second pipe diameter section 125 having two second wave bars 1251, and each second wave bar 1251 may be regarded as a closed loop or non-closed loop structure formed by a continuous curved extension of a bar member in a Z-shape or a W-shape.

The second wave bars 1251 can be extended and contracted in the radial direction so that adjacent peaks and adjacent valleys between the respective second wave bars 1251 can be close to or distant from each other. At the time of natural expansion, the diameter of the second wavy rod 1251 becomes large, and the axial interval between the crests and the troughs becomes small while the circumferential interval becomes large. When the thrombus taking support 1 reaches the thrombus position of a lesion part, the second wave-shaped rod 1251 expands by self to open the thrombus, so that the thrombus can be opened, a blood flow channel is established, and the function of pre-dredging is realized; and the thrombus is cut by the second wave bar 1251, and the cut thrombus portion enters the second wave bar 1251 to be captured by the second mesh 102.

In one embodiment, referring to fig. 7, second contoured bar 1251, proximally located second diameter section 125, is circumferentially discontinuous to form a plurality of circumferentially discontinuous second mesh openings 102 and such that the proximal end of second diameter section 125 forms a larger mesh opening 102a than second mesh openings 102. Fig. 7 illustrates that the number of second mesh holes 102 and mesh openings 102a is two and the two are alternately arranged in the circumferential direction. The larger mesh opening 102a facilitates capture of escaping thrombus during withdrawal of the thrombectomy stent 1 to capture it within the thrombectomy stent 1.

With continued reference to fig. 7, the adjacent two second wave bars 1251 configured to form second mesh openings 102 are defined as proximal second wave bars 1251 and distal second wave bars 1251. The axial dimension of the proximal second wave bar 1251 is smaller than that of the distal second wave bar 1251, so that the size of the second mesh openings 102 enclosed by two adjacent second wave bars 1251 is smaller at the proximal end and larger at the distal end in the axial direction. So, based on near-end second wave form pole 1251 is shorter in the axial, distal end second wave form pole 1251 is longer in the axial, can shorten the distance between first pipe diameter section 121 and second pipe diameter section 125, the space of embolectomy support 1 capture thrombus is got in the increase for the thrombus imbeds more easily and gets in the embolus support 1, will strengthen the anchor effect to the thrombus piece like this, and can reduce the time that the thrombus escapes, ensure to get the efficiency promotion that embolus support 1 captures the thrombus.

The proximal ends of the first support rod 123 and the second support rod 124 are connected to the distal apices of the first corrugated pipe 1211 of the first tubular diameter section 121, for example, the proximal apices of the first corrugated pipe 1211, and the distal apices are freely suspended to hook the thrombus. The distal end of the first support rod 123 and the distal end of the second support rod 124 are both connected to the apex of the second contoured bar 1251 at the proximal end of the adjacent second diameter segment 125, such as to the proximal apex of the second contoured bar 1251.

The proximal end of the support arm 126 is connected to the apex of the second contoured bar 1251 of the second tubular section 125 at the distal end, such as the proximal apex of the second contoured bar 1251, which is free to hang to provide a thrombus catching function. The distal end of the support arm 126 is connected to the apex of the first contoured bar 1211 at the proximal end of the first diameter section 121 adjacent the distal end, such as to the proximal apex of the first contoured bar 1211.

It should be noted that, in the above description, the proximal end of the transition section 122 is connected to the proximal vertex of the proximal adjacent first wave bar 1211 located at the distal end along the axial direction of the embolectomy stent 1, in this case, the distal vertex of the first wave bar 1211 is suspended as a free end point, and the distal end of the transition section 122 is connected to the proximal vertex of the distal adjacent first wave bar 1211 located at the proximal end. It is understood that in other embodiments, the proximal end of the transition section 122 may be connected to the distal vertex of an adjacent first wave bar 1211, and the distal end of the transition section 122 is connected to the distal vertex of another adjacent first wave bar 1211, in which case the proximal vertex of the first wave bar 1211 is suspended as a free end. It should be noted that the difference between the two different designs is that the transition section 122 between two adjacent first diameter sections 121 is turned upside down (i.e. turned in the proximal and distal directions), so as to change the orientation of the free end point disposed on the first diameter section 121. Of course, given the ease of sheathing the embolectomy stent 1, a preferred embodiment would be to place the free end point at the distal end.

For ease of understanding, a preferred embodiment is illustrated in FIG. 7, wherein the proximal apex 1211a of the first undulating rod 1211, distal to the first diameter section 121, is a fixed apex and the distal apex 1211b is a free, floating end. The proximal and

distal apices

1211c and 1211d of the first proximal undulating rod 1211 of the first diameter section 121 are each a fixed apex.

The proximal vertex 1251a of the second contoured bar 1251 at the distal end of the second diameter section 125 is a fixed vertex, and the distal vertex 1251b of the second contoured bar 1251 at the distal end of the second diameter section 125 is a free end point that is free to hang. The proximal apex 1251c and the distal apex 1251d of the second contoured bar 1251 at the proximal end of the second diameter section 125 are both fixed apexes.

The proximal ends of the first support rod 123 and the second support rod 124 are connected to the proximal vertices 1211a of the first corrugated bar 1211 at the distal end of the first diameter section 121, and the distal ends of the first support rod 123 and the second support rod 124 are connected to the proximal vertices 1251c of the second corrugated bar 1251 at the proximal end of the adjacent second diameter section 125. The proximal end of the support arm 126 is connected to the proximal apex 1251a of the second contoured bar 1251 at the distal end of the second diameter section 125, and the distal end of the support arm 126 is connected to the proximal apex 1211c of the first contoured bar 1211 at the proximal end adjacent the first diameter section 121.

In an embodiment, with continued reference to fig. 7, the distal end of the first tube diameter section 121 extends towards the fixed vertices 1211a on both sides through the free end 1211b of the distal end to form a first catching unit 121a, the first catching unit 121a is alternately arranged with the first support rod 123 and the second support rod 124 and connected to each other, and the first catching unit 121a may have a V-shaped, W-shaped, zigzag, or U-shaped structure, so as to improve the catching efficiency of the thrombus. Fig. 7 illustrates that the number of the first catching units 121a is four, and the first support bar 123 and the second support bar 124 are opposite and located between two adjacent first catching units 121 a.

The distal end of the second pipe diameter section 125 extends toward the fixed vertex 1251a on both sides by a free end point 1251b of the distal end thereof to form a second catching unit 125a, and the second catching unit 125a and the support arm 126 are alternately arranged and connected to each other. The second catching unit 125a may have a V-shaped, W-shaped, zigzag, or U-shaped structure to improve the efficiency of catching thrombus. Fig. 7 illustrates that the number of the second catching units 125a is four, and the second catching units 125a are alternately arranged with the support arms 126 in the circumferential direction.

It should be noted that the first catching unit 121a extends outward or inward relative to the first pipe diameter section 121 to form a first receiving space 121b between the first catching unit 121a and the first support rod 123 and between the first catching unit 121a and the second support rod 124. The second catching unit 125a extends outward or inward with respect to the second pipe diameter section 125 to form a second housing space 125b between the second catching unit 125a and the support arm 126. The first catching unit 121a and the second catching unit 125a each extend outward or inward with respect to the second stent body 12. The bending direction of the first catching unit 121a is opposite to the bending direction of the first and second support bars 123 and 124, and the bending direction of the second catching unit 125a is opposite to the bending direction of the support arm 126. In this way, the space between the first accommodating space 121b and the second accommodating space 125b is increased, so that more accommodating spaces can be provided for thrombus, so that thrombus can enter the inner cavity of the thrombus taking support 1, and the capturing efficiency of the thrombus taking support 1 on thrombus is further improved. When the thrombectomy stent 1 is in a free state (i.e., an expanded state), the first catching unit 121a and the second catching unit 125a are inserted into the thrombi or the thrombi are clamped in the first receiving space 121b and the second receiving space 125b, thereby improving the anchoring of the thrombi by the thrombi removal stent 1. The first catching units 121a and the second catching units 125a are uniformly distributed in the circumferential direction of the second stent body 12, so that the flexibility of the embolectomy stent 1 is enhanced, and the efficiency of the embolectomy stent 1 in catching thrombus is improved.

It should be noted that, in one embodiment, the thrombectomy stent 1 described above further has the following characteristics: the thrombectomy stent 1 has a semi-free state and a free state. Wherein, the semi-free state (i.e. partially released state) refers to the operation state that the thrombectomy stent 1 is at least partially in an incompletely expanded state, for example, the operation state that the second stent body 12 is pressed by thrombus at the early stage of implantation of the thrombectomy stent 1 in the blood vessel, or the operation state that the second stent body 12 of the thrombectomy stent 1 is restrained by other restraining elements. The free state (i.e., fully released state) refers to the second stent body 12 of the embolectomy stent 1 being in a fully expanded working state or in a working state that is fully free (i.e., not constrained by other constraining elements).

In a semi-free state (not shown, refer to the drawings and description of the patent application filed earlier by the applicant on 30/5/2020, application No. 202010482816.8), the stent 1 is not fully expanded, and at least a part of the structure of the second stent body 12 is in a nearly single-layer tubular structure. In the free state, the embolectomy stent 1 is fully expanded, and the second stent body 12 is in an approximately double-layered tubular structure, and the radial dimension of the first diameter section 121 is larger than that of the second diameter section 125.

During the switching from the free state to the semi-free state, the radial distance between the free end point of the distal end of the first diameter section 121 and the proximal end vertex of the second diameter section 125 adjacent to the distal end thereof gradually decreases. The radial distance between a fixed apex at the proximal end of the first diameter segment 121 and a free end point at the distal end of the second diameter segment 125 adjacent to the proximal end thereof gradually decreases. Thereby ensuring that the single-layer reticular structure has smaller grid space.

Based on the thrombus taking support 1 has two states of semi-freedom and freedom, when the thrombus taking support 1 is in the semi-free state, at least part of the structure of the second support body 12 is of an approximate single-layer tubular structure, and the grid space on the single-layer net structure is small, so that the problem of blocking of an inner cavity caused by the fact that thrombus completely enters the inner cavity of the thrombus taking support 1 can be avoided, and the single-layer tubular structure can be used as a blood flow channel. In addition, when the thrombus removal support 1 is in a semi-free state, the radial supporting force of the whole thrombus removal support 1 is ensured by the single-layer tubular structure, so that a blood flow channel can be quickly established by the thrombus removal support 1, the blood flow blocking the blood vessel is recovered before thrombus removal, the function of pre-communicating the blood flow channel is realized at the early stage of thrombus removal, and the safety of thrombus removal operation is improved. Because when in the free state, the second stent body 12 is of an approximate double-layer tubular structure, the first pipe diameter section 121 with a large pipe diameter has a larger grid structure, and a certain space is reserved between the first pipe diameter section 121 and the second pipe diameter section 125, so that thrombus is allowed to completely enter the inner cavity of the thrombus removal stent 1, and the thrombus removal efficiency is improved. Further, get and tie support 1 and adopt the sectional type design, also be first pipe diameter section 121 and second pipe diameter section 125 interval in proper order and evenly arrange to can improve and get a tie support 1 compliance, and ensure to get a tie support 1 and can adapt to the blood vessel of different crooked forms, also can strengthen the anchor effect to the thrombus block simultaneously, for example when receiving the extrusion in the blood vessel, get a tie support 1 and can make great deformation.

In the free state, an orthographic projection of the first diameter section 121 on the reference plane partially overlaps with an orthographic projection of the second diameter section 125 on the reference plane. So, guarantee to get and tie the radial holding power of support 1 in the blood vessel of different diameters to effectively prevent to get and tie support 1 and take place to sink when passing through blood vessel completely, and then improved thrombus and caught efficiency, and got and tie the in-process and reduced the damage that support 1 led to the fact the vascular wall. In the semi-free state, an orthographic projection of the first diameter section 121 on the reference plane does not overlap with an orthographic projection of the second diameter section 125 on the reference plane. Wherein, the reference plane is a plane parallel to the central axis of the bolt taking bracket 1. Therefore, the embolectomy support 1 is in a partial release state, the whole structure or partial structure of the second support body 12 is a single-layer tubular structure with an approximate closed-loop structure, the metal covering of the single-layer tubular structure is denser, so that thrombus is prevented from entering the inside of the single-layer tubular structure, the embolectomy support 1 is provided with a cavity for blood flow flowing in the partial release state, and the safety of embolectomy is improved.

In one embodiment, when the second rack body 12 is in the semi-free state, the first supporting rod 123, the second supporting rod 124 and the supporting arm 126 are all in a straight rod-shaped structure. When the second rack body 12 is in the free state, the first support rod 123, the second support rod 124, and the support arm 126 are all in a curved structure and are curved inward or outward relative to the second rack body 12. So, under free state, because first bracing piece 123 and second bracing piece 124 all are crooked column structure to can reduce the cutting to the thrombus, and can provide more accommodation space for the thrombus, so that the thrombus gets into the inner chamber of embolectomy support 1, and then improved the efficiency of arresting of embolectomy support 1 to the thrombus. In the semi-free state, the first support rod 123 and the second support rod 124 are both straight rod-shaped structures, and the first support rod 123 and the second support rod 124 are approximately parallel to the axial direction of the second stent body 12, so that the whole embolectomy stent 1 can be compressed to form a single-layer tubular structure with a closed-loop structure and approximately the same outer diameter, a blood flow channel pre-communicating function is realized, and brain injury in the operation process is reduced.

Referring to fig. 1 and 2, the embolectomy stent 1 further comprises a third stent body 13 connected to the distal end of the second stent body 12, the third stent body 13 is in smooth transition connection with the second stent body 12, and the third stent body 13 is communicated with the interior of the second stent body 12, so that the interior of the embolectomy stent 1 forms a continuous channel. The third stent body 13 can further capture thrombus falling off or overflowing from the second stent body 12, so that the thrombus falling off or overflowing from the second stent body 12 can enter an internal channel of the third stent body 13, thereby effectively preventing the thrombus from being separated from the embolectomy stent 1 and improving the capturing effect.

The third stent body 13 comprises a capturing section 131 and an extending section 132, the proximal end of the capturing section 131 is connected to the second diameter section 122 at the distal end of the second stent body 12 by a plurality of support arms 126, and the distal end of the capturing section 131 is connected to the proximal end of the extending section 132. Wherein the catching section 131 has third net holes 103 arranged circumferentially, the extending section 132 has fourth net holes 104 arranged circumferentially, and the area of the third net holes 103 is larger than the area of the first net holes 101, the area of the second net holes 102 and the area of the fourth net holes 104. In addition, the distal ends of the extensions 132 may converge toward each other to close the distal end of the thrombectomy stent 1, forming a closed distal end of the thrombectomy stent 1, to prevent thrombi trapped in the thrombectomy stent 1 from escaping from the closed distal end. It will be appreciated that in other embodiments, the distal ends of the extensions 132 may not converge toward each other, for example, the distal ends of the extensions 132 may be free ends, or alternatively, the distal ends of the extensions 132 may be connected to a capture net.

It should be noted that the first bracket body 11, the second bracket body 12, and the third bracket body 13 may be an integrally formed structure, so as to facilitate the manufacture of the bolt taking bracket 1, and ensure the stability and reliability of the connection of the first bracket body 11, the second bracket body 12, and the third bracket body 13. The thrombus removal support 1 is processed by laser cutting of a nickel titanium tube material, so that the thrombus is effectively prevented from being separated from the inside of the thrombus removal support 1. The third stent body 13 is arranged at the far end of the thrombus taking stent 1, the catching section 131 of the third stent body 13 is formed by jointly enclosing a third mesh 103 with a relatively large mesh area, the extending section 132 of the third stent body 13 is formed by jointly enclosing a fourth mesh 104 with a relatively small mesh area, and therefore large-volume thrombus and small-volume thrombus which escape to the far end from the thrombus taking stent 1 can enter a channel inside the third stent body 13 from the third mesh 103, and the thrombus caught by the third stent body 13 is accommodated by the extending section 132, so that the catching efficiency of the thrombus taking stent 1 is further improved.

The extension section 132 includes a plurality of third wave bars 1321, the plurality of third wave bars 1321 are sequentially connected end to end along the axial direction of the embolectomy stent 1, and two adjacent third wave bars 1321 form a plurality of fourth mesh openings 104 arranged circumferentially. The shape of the fourth mesh openings 104 is a diamond structure in this embodiment, but in other embodiments, the fourth mesh openings 104 may also be mesh structures with other shapes, such as triangle, rectangle, polygon, etc., and the present application is not limited thereto. It should be noted that, in the proximal-to-distal direction, the radial dimension of the third wave bars 1321 in the extension 132 is gradually reduced, which gradually reduces the dimension of the fourth mesh openings 104 enclosed by the two axially adjacent third wave bars 1321. Therefore, the resistance of the thrombus removal support 1 in the pushing process is reduced, and the thrombus removal support 1 is convenient to recover into the micro-catheter.

The third wave bars 1321 are capable of expanding and contracting in the radial direction so that adjacent peaks and adjacent valleys between the respective third wave bars 1321 can be close to or distant from each other. At natural expansion, the diameter of the third wave bar 1321 becomes larger, and the axial spacing between the peaks and valleys becomes smaller while the circumferential spacing becomes larger. When the thrombus taking support 1 reaches the thrombus position of the lesion part, the third wave-shaped rod 1321 expands by self to expand, so that the thrombus can be opened, a blood flow channel is established, and the function of pre-dredging is realized; and the thrombus is cut by the third wave bars 1321, and the cut thrombus portion enters the third wave bars 1321 to be captured by the fourth mesh holes 104.

The catching section 131 includes at least one third mesh 103 and a plurality of reinforcements 1311, and the at least one third mesh 103 and the plurality of reinforcements 1311 are connected side by side in the circumferential direction of the third stent body 13. Each reinforcement portion 1311 includes a fifth mesh 105 and a skeleton bar 106 provided at a proximal end of the fifth mesh 105, and a proximal end of the skeleton bar 106 is connected to a distal end of the support arm 126. In this embodiment, the area of third mesh 103 is larger than the area of fourth mesh 104 and the area of fifth mesh 105, so that escaped thrombus is collected by third mesh 103 and the collected thrombus is prevented from escaping from fourth mesh 104 and fifth mesh 105.

Fig. 1 and 2 show that the number of the third mesh holes 103 corresponds to the number of the reinforcement parts 1311, and the third mesh holes 103 and the reinforcement parts 1311 are alternately connected in the circumferential direction of the third stent body 13. In this embodiment, the capturing section 131 includes two diametrically opposed third mesh holes 103 and two diametrically opposed reinforcing portions 1311, and the third mesh holes 103 and the reinforcing portions 1311 are connected side by side and alternately in the circumferential direction of the third stent body 13. Thus, the catching performance of the third mesh holes 103 on thrombus (such as hard thrombus like organized thrombus and calcified thrombus) which is not effectively caught by the second stent body 13 and thrombus with larger volume) is improved, the radial supporting force of the third stent body 13 is ensured, and the transition deformation of the third stent body 13 is avoided to reduce the adherence of the catching section 131, namely, the catching section 131 of the third stent body 13 is prevented from collapsing.

In one embodiment, skeletal rod 106 is configured in a wye configuration. For easy understanding, referring to fig. 1 and 2, the skeletal rod 106 includes a first reinforcing rod 1061 and a second reinforcing rod 1062, and the second reinforcing rod 1062 is connected between the first reinforcing rod 1061 and the fourth mesh 104. Wherein the first reinforcement bar 1061 is configured as a V-shaped structure, and two proximal apexes of the V-shaped structure are connected to the distal end of the support arm 126.

In one embodiment, the proximal end of each third mesh 103 is formed with a third catching unit 103a, the proximal end of the third catching unit 103a is connected to the distal ends of the support arms 126, and the distal end of the third catching unit 103a is configured as a free end and is located between two adjacent support arms 126, or can be understood as being located between two adjacent frame bars 106. The third capturing unit 103a may have a V-shaped, W-shaped, zigzag, or U-shaped structure to improve the capturing efficiency of the thrombus. Fig. 1 and 2 show that the third capturing units 103a are V-shaped and two in number, and two third capturing units 103a are arranged opposite to each other.

It should be noted that the third capturing unit 103a extends outward or inward relative to the third stent body 13 to form a third housing space 103b between the third capturing unit 103a and the capturing section 131. Thus, the space of the third accommodating space 103b is increased, and more accommodating space can be provided for thrombus, so that the thrombus can enter the inner cavity of the thrombus taking support 1, and the thrombus capturing efficiency of the thrombus taking support 1 is further improved. When the thrombectomy stent 1 is in a free state (i.e. an expanded state), the third catching unit 103a is inserted into the thrombus or clamps the thrombus in the third receiving space 103b, thereby improving the anchoring of the thrombectomy stent 1 to the thrombus. The third capturing units 103a are uniformly distributed on the circumference of the third stent body 13, so that the flexibility of the embolectomy stent 1 is enhanced, and the capturing efficiency of the embolectomy stent 1 on thrombus is improved.

Referring to fig. 8, fig. 8 is a partial schematic view of the pull wire 2 of fig. 1 attached to the proximal end of the thrombectomy stent 1. In one embodiment, the thrombectomy support 1 further comprises a proximal connector 14, the proximal connector 14 can be a hollow tubular structure with two open ends, the proximal end of the thrombectomy support 1 converges to the distal end of the proximal connector 14, for example, the proximal end of the thrombectomy support 1 can be adhesively fixed to the distal end of the proximal connector 14.

The outer surface of the proximal connector 14 is provided with a first window 141 communicated with the inside of the proximal connector 14, when the distal end of the traction guide wire 2 passes through the proximal end of the proximal connector 14 and is opposite to the first window 141, the part of the distal end of the traction guide wire 2 exposed out of the first window 141 can be fixed by the fixing head 21, and the fixing head 21 can be a welding head or an adhesive joint. For example, in order to fix the distal end of the guide wire 2 to the proximal end of the thrombectomy stent 1, the distal end of the guide wire 2 may first pass through the proximal end of the proximal connector 14, and the distal end of the guide wire 2 is exposed out of the first fenestration 141, at this time, the portion of the guide wire 2 exposed out of the first fenestration 141 may be welded or bonded, which is very convenient for the user to operate.

It should be noted that the fixing head 21 at the distal end of the pull wire 2 may be a spherical joint as illustrated in fig. 8, a T-shaped joint as illustrated in fig. 9, or any other shape, and the shape of the fixing head 21 is only used as an example in this application, and is not exhaustive and is not limited to this application. Referring to fig. 9 and 10, the first window 141 may be a hole formed on the outer surface of the proximal connector 14 as shown in fig. 8, or may be a notch as shown in fig. 9 and 10. Regardless of the form of the first window 141 being an opening or a notch, the radial dimension of the fixing head 21 is smaller than the outer diameter of the proximal connector 14, thereby preventing the fixing head 21 from protruding too far from the proximal connector 14 in the radial direction, and preventing the fixing head 21 from protruding in the radial direction to increase the resistance to retraction of the embolectomy stent 1.

Referring to fig. 11, the thrombus removal support 1 further includes a distal end connector 15 and a developing guide wire 16, the distal end of the thrombus removal support 1 is converged to the proximal end of the distal end connector 15, and the outer surface of the distal end connector 15 is provided with a second window 151 communicated with the inside of the distal end connector 15. When the proximal end of the visualization guide wire 16 passes through the distal end of the distal end connector 15 and is aligned with the second window 151, the portion of the proximal end of the visualization guide wire 16 exposed to the second window can be fixed by a mounting head (not shown). The mounting head is understood herein to be a cured flux or adhesive that is accessible through the second window 151 for attachment to the proximal end of the visualization guidewire 16.

It should be noted that the visualization guide wire 16 may be made of a memory alloy, a platinum-tungsten alloy, and a silver-tin alloy. The arrangement of the developing guide wire 16 can facilitate the indication of the position of the distal end of the third stent body 13 of the embolectomy stent 1 through the position of the developing guide wire 16 under the detection of an instrument. The development guide wire 16 extends along the axial direction of the embolectomy stent 1, the distal end of the development guide wire 16 is bent towards the inner side of the embolectomy stent 1, and the development guide wire 16 bent towards the inner side of the embolectomy stent 1 can effectively reduce the damage of the free end of the development guide wire 16 to the blood vessel.

The invention also provides an embolectomy system, which comprises the embolectomy device 100, the push rod 200, the loading sheath 300, the micro-catheter 400 and the sheath 500 of any embodiment.

Wherein, the push rod 200 is connected with the proximal end of the thrombectomy stent 1 and is used for pushing and pulling the thrombectomy stent 1. The loading sheath 300 is used to house the embolectomy device 100 in a compressed state. The microcatheter 400 is adapted to communicate with the loading sheath 200 and a lumen within the microcatheter 400 is adapted to deliver the thrombectomy device 100. The sheath 500 is sleeved outside the micro-catheter 400, and the sheath 500 extends into the blood vessel along with the micro-catheter 400 and is conveyed to the proximal end of the thrombus at the lesion part for accommodating the thrombus captured by the thrombus removal stent 1 during retraction.

For ease of understanding, the present invention will be described in connection with the operation of the embolectomy system as described in connection with FIGS. 12-20.

Referring first to fig. 12 to 14, before use, the thrombectomy device 100 according to the embodiment of the present invention is loaded in a collapsed configuration in a thrombectomy system, which includes the above-mentioned push rod 200, loading sheath 300, micro-catheter 400 and sheath 500 (refer to fig. 19).

The proximal end of the thrombus taking support 1 is converged and connected on the proximal end connector 14 through the first support body 11, the hollow proximal end connector 14 is communicated with the push rod 200, the push rod 200 is a flexible tube capable of radially bending, and the proximal end of the traction guide wire 2 sequentially penetrates out of the proximal end connector 14 and the push rod 200.

The loading sheath 300 is sleeved outside the push rod 200, and before use, the thrombectomy stent 1 is pre-compressed and guided into the loading sheath 300, as shown in the state of fig. 12.

When a thrombectomy procedure is required, the loading sheath 300 may be connected to the microcatheter 400 via a connector 600 (e.g., a luer connector), as shown in FIG. 13. And then the proximal connector 14 and the thrombectomy stent 1 are pushed by the push rod 200 to enter the lumen of the microcatheter 400 smoothly, as shown in FIG. 14. The thrombus removal device 100 is then conveyed to the lesion position of the thrombus determined by radiography or other diagnostic means through the microcatheter 400, so that the thrombus removal stent 1 is released at the vascular lesion position and can realize accurate alignment of push-pull action through the push rod 200, and the thrombus removal stent 1 is converted between a compressed state and a released state.

The sheath 500 is sleeved outside the micro-catheter 400, extends into the blood vessel along with the micro-catheter 400, and is conveyed to the proximal end of the thrombus at the lesion part, so as to receive the thrombus captured by the thrombus removal stent 1 during retraction.

Referring to fig. 15 to 20, in the interventional thrombectomy stent, referring to fig. 15, a perforated guide wire 700 is used to pass through a thrombus 01 at a lesion site in advance to establish a vascular access in the thrombus. Referring to fig. 16, the microcatheter 400 and sheath 500 are delivered over the fenestrated guidewire 700 to the thrombus 01 at the lesion site, and the microcatheter 400 is passed over the thrombus 01, securing the microcatheter 400, and withdrawing the fenestrated guidewire 700. Referring to FIG. 17, the thrombectomy device 100 is pushed by the push rod 200 to the location of the thrombus 01, as determined by imaging or other diagnostic means. Referring to fig. 18, the push rod 200 is stopped to push forward, the push rod 200 is fixed and the micro-catheter 400 is withdrawn, so that the thrombus removal support 1 is released at the far end of the micro-catheter 400, the thrombus 01 is ensured to be positioned in the effective area of the thrombus removal device 100 according to the position of the development point of the development guide wire 16 on the image, and the thrombus removal support 1 is completely released in the blood vessel, so that the thrombus 01 is embedded into the thrombus removal support 1.

Referring to fig. 19 and 20, the pull guide wire 2 and the push rod 200 are pulled simultaneously to withdraw the thrombectomy stent 1 with the captured thrombus 01 and to the sheath 500, completing the thrombectomy.

Referring to fig. 19 and 20, in the process of pulling the thrombus taking support 1 to retract by pulling the guide wire 2, the first diameter sections 121 can adapt to blood vessels with different diameters, so as to ensure the adherence performance with the blood vessels, on this basis, the two axially adjacent first diameter sections 121 are arranged in an included angle in the radially contracted area, that is, the two axially adjacent first diameter sections 121 are different in radially contracted position, the radially contracted area is dislocated, it can be understood that the radially uncontracted area is also dislocated, which means that when the thrombus taking support 1 is pulled after capturing thrombus 01 in a blood vessel, the thrombus taking support 1 can maintain the shape in different directions through the undistorted area of the first diameter sections 121, so as to improve the radial support force, the whole thrombus taking support 1 will not obviously collapse, and the thrombus taking support 1 capable of maintaining the shape in different directions increases the resistance of the thrombus 01, and the contact area of the thrombus 01 in the blood vessels with different bending degrees of the thrombus taking support 1 is still kept, so that the thrombus 01 in different directions can be effectively captured, and the risk of escaping the thrombus 01 is reduced.

While the present invention has been described with reference to several exemplary embodiments, it is understood that the terminology used is intended to be in the nature of words of description and illustration, rather than of limitation. As the present invention may be embodied in several forms without departing from the spirit or essential characteristics thereof, it should also be understood that the above-described embodiments are not limited by any of the details of the foregoing description, but rather should be construed broadly within its spirit and scope as defined in the appended claims, and therefore all changes and modifications that fall within the meets and bounds of the claims, or equivalences of such meets and bounds are therefore intended to be embraced by the appended claims.

Claims

1. A thrombectomy support, comprising:

a first bracket body;

a second stent body disposed at a distal end of the first stent body; the second stent body comprises a first pipe diameter section and a transition section; the first pipe diameter sections and the transition sections are alternately arranged along the axial direction of the bolt taking support, and two adjacent first pipe diameter sections are connected through the transition sections; when the proximal end and the distal end of the embolectomy support are relatively far away from each other along the axial direction, at least partial areas of the first pipe diameter sections are radially contracted, and two areas of the first pipe diameter sections, which are adjacent to each other in the axial direction, radially contracted are arranged at included angles.

2. The embolectomy support of claim 1, wherein the radially contracted regions of two axially adjacent first tubular diameter sections are circumferentially offset relative to each other by an angle of 90 degrees.

3. The embolectomy stent of claim 2, wherein the first tubular diameter section has first and second diametrically opposed regions and third and fourth diametrically opposed regions, the first, third, second and fourth regions being arranged sequentially in a circumferential direction of the second stent body;

when the proximal end and the distal end of the embolectomy stent are relatively far away along the axial direction, the first area and the second area contract radially, the radial contraction size of the third area and the fourth area is unchanged, or the radial contraction size of the third area and the fourth area is smaller than that of the first area and/or that of the second area.

4. The embolectomy stent of claim 2, wherein when the first tubular diameter section radially contracts, the radial dimension of the radially contracted region of the first tubular diameter section is circumferentially small in the middle and large at both ends.

5. The embolectomy support of claim 1, wherein two axially adjacent transition sections are circumferentially relatively offset, two axially adjacent first tubular diameter sections are circumferentially relatively offset, and the two axially adjacent transition sections are circumferentially relatively offset by an angle equal to the circumferentially offset angle of the two axially adjacent first tubular diameter sections.

6. The embolectomy stent of claim 5, wherein the transition section comprises first and second support bars spaced apart along the circumference of the second stent body, the first and second support bars being disposed between the proximal and distal ends of two adjacent first diameter sections.

7. The embolectomy stent of claim 6, wherein two axially adjacent transition sections are circumferentially offset by 90 degrees; the first supporting rod and the second supporting rod are circumferentially spaced by 180 degrees.

8. The embolectomy support of claim 6, wherein the first tubular diameter section comprises a plurality of first wavy rods, the first wavy rods are sequentially connected end to end along the axial direction of the embolectomy support, and two adjacent first wavy rods form a plurality of first mesh holes which are circumferentially arranged.

9. The embolectomy stent of claim 8, wherein the proximal ends of the first and second support rods are each connected to the apex of a first undulating bar distally adjacent to the proximal end of the first tubular section, and the distal ends of the first and second support rods are each connected to the apex of a first undulating bar proximally adjacent to the distal end of the first tubular section.

10. The embolectomy stent of claim 6, wherein the transition section further comprises a second diameter section and a plurality of support arms, the plurality of support arms being circumferentially spaced along the second stent body, a proximal end of the second diameter section being connected to a distal end of the first support bar and a distal end of the second support bar, the distal end of the second diameter section being connected to the proximal end of the first diameter section via the plurality of support arms;

the thrombectomy stent has a semi-free state in which the thrombectomy stent is not fully expanded and a free state in which at least a portion of the structure of the second stent body is in an approximately single-layered tubular structure; in the free state, the embolectomy stent is fully expanded, the second stent body is of an approximately double-layer tubular structure, and the radial dimension of the first pipe diameter section is larger than that of the second pipe diameter section.

11. The embolectomy stent of claim 10, wherein in the free state, an orthographic projection of the first diameter segment at a reference plane partially overlaps an orthographic projection of the second diameter segment at the reference plane; in the semi-free state, an orthographic projection of the first diameter section on the reference plane is not overlapped with an orthographic projection of the second diameter section on the reference plane;

the reference plane is a plane parallel to the central axis of the embolectomy support.

12. The embolectomy support of claim 10, wherein in the semi-free state, the first support bar, the second support bar, and the support arm are each in a straight rod-like configuration;

in the free state, the first support rod, the second support rod and the support arm are of a bent structure and are bent inwards or outwards relative to the second support body.

13. The embolectomy support of claim 10, wherein the first tubular diameter section comprises a plurality of first wavy rods, the first wavy rods are sequentially connected end to end along the axial direction of the embolectomy support, and two adjacent first wavy rods form a plurality of circumferentially arranged first meshes; the second pipe diameter section includes a plurality of second wave form poles, and is a plurality of second wave form pole is followed the axial of thrombectomy support is met end to end in order, two adjacent second wave form pole forms a plurality of second meshs that circumference was arranged.

14. The embolectomy stent of claim 13, wherein the proximally located second undulating bars of the second tubular diameter section are circumferentially discontinuous to form a plurality of circumferentially discontinuous second mesh openings and such that the proximal end of the second tubular diameter section forms a larger mesh opening than the second mesh openings.

15. The embolectomy stent of claim 13, wherein the axial dimension of the second undulating bars of the second tubular section at the proximal end is smaller than the axial dimension of the second undulating bars of the second tubular section at the distal end, so that the size of the second mesh openings formed by the enclosing of two adjacent second undulating bars is smaller at the proximal end and larger at the distal end in the axial direction.

16. The embolectomy stent of claim 13, wherein the proximal ends of the first and second support rods are each connected to the apex of a first undulating bar distally located from the proximal adjacent tubular diameter section of the first support rod, and the distal ends of the first and second support rods are each connected to the apex of a second undulating bar proximally located from the distal adjacent tubular diameter section of the second support rod;

the near end of the supporting arm is connected with the vertex of a second wave-shaped rod of which the second pipe diameter section is positioned at the far end, and the far end of the supporting arm is connected with the vertex of a first wave-shaped rod of which the adjacent first pipe diameter section is positioned at the near end.

17. The embolectomy stent of claim 16 wherein the proximal ends of the first and second support rods are connected to the proximal apices of first tubular sections distally adjacent to the proximal ends of the first struts and the distal ends of the first and second support rods are connected to the proximal apices of second tubular sections proximally adjacent to the distal ends of the second struts;

the near end of the supporting arm is connected with the near end vertex of the second wave-shaped rod of the second pipe diameter section positioned at the far end, and the far end of the supporting arm is connected with the near end vertex of the first wave-shaped rod of the adjacent first pipe diameter section positioned at the near end.

18. The embolectomy support of claim 17, wherein the proximal apex of the first undulating rod at the distal end of the first tubular section is a fixed apex and the distal apex is a free end point; the near end vertex and the far end vertex of a first wave-shaped rod of which the first pipe diameter section is positioned at the near end are both fixed vertexes;

the near end vertex of the second wave-shaped rod of the second pipe diameter section positioned at the far end is a fixed vertex, and the far end vertex of the second wave-shaped rod of the second pipe diameter section positioned at the far end is a free endpoint; the near end vertex and the far end vertex of a second wave-shaped rod of which the second pipe diameter section is positioned at the near end are fixed vertexes.

19. The embolectomy stent of claim 18, wherein during switching from the free state to the semi-free state, the radial distance between a free end point of the distal end of the first tubular diameter section and a proximal apex of the second tubular diameter section adjacent the distal end thereof gradually decreases;

the radial distance between the fixed vertex of the near end of the first pipe diameter section and the free end point of the far end of the second pipe diameter section adjacent to the near end of the first pipe diameter section is gradually reduced.

20. The embolectomy stent of claim 18, wherein the distal end of the first tubular diameter section extends towards the fixed apices of both sides through the free end point of the distal end thereof to form a first catching unit; the first catching unit, the first supporting rod and the second supporting rod are alternately arranged and connected with each other;

the far end of the second pipe diameter section extends towards the fixed top points on two sides through the free end point of the far end of the second pipe diameter section to form a second capturing unit; the second catching units and the support arms are alternately arranged and connected with each other.

21. The embolectomy support of claim 20, wherein the first capture unit extends outwardly or inwardly relative to the first tubular section to form a first receiving space between the first capture unit and the first support bar and between the first capture unit and the second support bar; the second capturing unit extends outwards or inwards relative to the second pipe diameter section so as to form a second accommodating space between the second capturing unit and the supporting arm.

22. The embolectomy support of claim 13, further comprising a third support body attached to the distal end of the second support body, the third support body being in communication with the interior of the second support body such that the interior of the embolectomy support forms a continuous channel;

the third stent body comprises a capturing section and an extending section, the proximal end of the capturing section is connected to the second diameter section at the distal end of the second stent body through the plurality of support arms, and the distal end of the capturing section is connected to the proximal end of the extending section; wherein the catching section is provided with third meshes arranged circumferentially, and the area of the third meshes is larger than that of the first meshes and that of the second meshes.

23. The embolectomy stent of claim 22, wherein the extension section comprises a plurality of third corrugated rods, the third corrugated rods are sequentially connected end to end along the axial direction of the embolectomy stent, and two adjacent third corrugated rods form a plurality of fourth mesh openings which are circumferentially arranged; the distal ends of the extension sections converge toward each other to close the distal end of the thrombectomy support, forming a distal closed end of the thrombectomy support.

24. The embolectomy stent of claim 23, wherein the capturing section comprises at least one third mesh and a plurality of reinforcements, the at least one third mesh and the plurality of reinforcements being connected side-by-side along a circumference of the third stent body; each reinforcing part comprises a fifth mesh and a skeleton rod arranged at the near end of the fifth mesh, and the near end of the skeleton rod is connected with the far end of the supporting arm; the area of the third mesh is larger than the area of the fourth mesh and the area of the fifth mesh.

25. The embolectomy stent of claim 22, wherein a proximal end of each third mesh opening is formed with a third capture unit, the proximal end of the third capture unit being connected to the distal end of the support arm; the far end of the third capture unit is configured as a free end and is positioned between two adjacent support arms.

26. The embolectomy stent of claim 25, wherein the third capture unit extends outwardly or inwardly relative to the third stent body to form a third receptacle with the capture segment.

27. An embolectomy device, comprising an embolectomy stent of any of claims 1 to 26 and a pull guidewire connected to the embolectomy stent;

the traction guide wire is connected with the proximal end of the thrombus removal support and used for pushing and pulling the thrombus removal support.

28. The embolectomy device of claim 27, wherein the embolectomy support further comprises a proximal connector, the proximal end of the embolectomy support converging to the distal end of the proximal connector; the outer surface of the near-end connector is provided with a first window communicated with the inside of the near-end connector;

when the far end of the traction guide wire penetrates through the near end of the near end connector and is aligned to the first window, the part, exposed out of the first window, of the far end of the traction guide wire can be fixed by the fixing head.

29. The embolectomy device of claim 27, wherein the embolectomy stent further comprises a distal connector and a visualization guidewire, the distal end of the embolectomy stent converging to the proximal end of the distal connector; the outer surface of the far-end connector is provided with a second window communicated with the interior of the far-end connector;

when the proximal end of the developing guide wire penetrates through the distal end of the distal end connector and is aligned to the second window, the part, exposed out of the second window, of the proximal end of the developing guide wire can be fixed by the mounting head.

30. The embolectomy device of claim 29, wherein the visualization guidewire extends in an axial direction of the embolectomy stent, and a distal end of the visualization guidewire is bent toward an inner side of the embolectomy stent.

31. An embolectomy system comprising an embolectomy device as defined in any of claims 27 to 30, together with a pusher, loading sheath and microcatheter;

the push rod is connected with the near end of the thrombus taking support and is used for pushing and pulling the thrombus taking support;

the loading sheath is used for accommodating the embolectomy device in a compressed state;

the micro-catheter is used for being communicated with the loading sheath, and the lumen in the micro-catheter is used for conveying the thrombus removal device.