Thrombectomy device

Abstract

The thrombectomy device comprises a thrombectomy support, a connecting pipe and a traction wire, an inner cavity is formed in the thrombectomy support with the traction wire, the thrombectomy support with the traction wire comprises a cutting part located at the near end, and an opening which is communicated with the inner cavity of the traction wire and is closed in the circumferential direction is formed in the cutting part of the traction wire. The traction wire cutting part comprises a far-end end part and a near-end end part which have an axial distance; the connecting rod is connected with the near-end end part of the traction wire thrombectomy bracket; the far end of the traction wire is connected with the traction wire thrombectomy support, and when the traction wire is subjected to traction action pointing to the near end, the traction wire applies radial compression force to the traction wire thrombectomy support. The thrombus extraction efficiency of the thrombus extraction device is high.

Description

Technical Field

[0001] This invention relates to the technical field of medical devices, and more particularly to a thrombectomy device. Background Technology

[0002] This section provides only background information relevant to this disclosure and is not necessarily prior art.

[0003] The thrombectomy device includes a thrombectomy stent with an open end (i.e., a cutting portion), located proximally to the stent. During thrombectomy, the cutting portion of the stent is initially positioned distal to the thrombus, with the open end facing proximally (towards the thrombus). A proximal driving force is then applied to the stent, propelling it along the vessel towards the thrombus, causing the cutting portion to axially embed and cut the thrombus. The dissected thrombus enters the lumen of the stent through the cutting portion. Finally, the stent, after collecting the thrombus, is withdrawn from the body.

[0004] An ideal thrombectomy device should be able to scrape away thrombi attached to the vessel wall as the thrombectomy stent moves. However, because the thrombectomy stent deforms to some extent during the process of being pulled and moved, it cannot effectively scrape away thrombi, resulting in low thrombectomy efficiency. Summary of the Invention

[0005] Therefore, it is necessary to provide a thrombectomy device with high thrombectomy efficiency.

[0006] A thrombectomy device includes a thrombectomy bracket, a connecting tube, and a traction wire. The thrombectomy bracket has an inner cavity and includes a cutting portion located at a proximal end. The cutting portion has a circumferentially closed opening communicating with the inner cavity. The cutting portion includes a distal end and a proximal end with an axial distance between them and is connected to the proximal end of the thrombectomy bracket. The distal end of the traction wire is connected to the thrombectomy bracket. When the traction wire is subjected to a traction action pointing towards the proximal end, the traction wire applies a radial compressive force to the thrombectomy bracket.

[0007] In the aforementioned thrombectomy device, the distal end of the traction wire is connected to the thrombectomy stent, and the connecting tube is connected to the proximal end of the stent. During thrombectomy, when the stent is moved by pulling the connecting tube proximally to scrape away the thrombus on the blood vessel, the cutting portion of the stent is subjected to axial traction, resulting in a decrease in the radial dimension of the opening. By simultaneously pulling the traction wire proximally, the stent experiences a certain degree of radial contraction at the connection point with the traction wire, correspondingly causing the opening of the cutting portion to contract on both sides in one direction. Since the opening is circumferentially closed, radial expansion occurs on both sides of the opening in the direction perpendicular to that direction, thereby mitigating the degree of reduction in the radial dimension of the opening caused by the traction of the connecting tube on the proximal end. Therefore, during thrombectomy, the opening of this thrombectomy device can remain in a state close to or adjacent to the blood vessel wall, thus helping to improve thrombectomy efficiency. Attached Figure Description

[0008] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0009] in:

[0010] Figure 1 This is a perspective view of a thrombectomy device in one embodiment, wherein the handle of the thrombectomy device is not shown in the figure;

[0011] Figure 2 This is a schematic diagram of the thrombectomy device in one embodiment, wherein the handle of the thrombectomy device is not shown in the figure;

[0012] Figure 3 This is a projection of the cut portion in a radially expanded state in one embodiment onto a plane perpendicular to the axis of the thrombectomy bracket.

[0013] Figure 4 In one embodiment, during the thrombectomy process, after the proximal end and distal end of the cutting part are relatively far apart, the projection of the cutting part in a plane perpendicular to the axis of the thrombectomy bracket is shown.

[0014] Figure 5 This is a schematic diagram of the thrombectomy stent in one embodiment;

[0015] Figure 6 for Figure 5 The diagram showing the unfolding of the third interval;

[0016] Figure 7 This is a perspective view of the delivery sheath and handle in a thrombectomy device according to one embodiment;

[0017] Figure 8A This is a perspective view of the thrombectomy device in another embodiment, wherein the handle and protective sleeve of the thrombectomy device are not shown in the figure;

[0018] Figure 8B for Figure 8A The illustrated embodiment is a schematic diagram of the thrombectomy device, wherein the handle of the thrombectomy device is not shown in the figure;

[0019] Figure 9 for Figure 8A Enlarged view of the middle S;

[0020] Figure 10 This is a cross-sectional view of the protective sleeve in another embodiment. Detailed Implementation

[0021] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0022] In the description of the embodiments of the present invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the embodiments of the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the embodiments of the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0023] In the description of the embodiments of the present invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a replaceable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of the present invention based on the specific circumstances.

[0024] In the field of interventional medical devices, the end of a medical device implanted in the human or animal body that is closer to the operator is generally called the "proximal end," and the end that is farther from the operator is called the "distal end." Based on this principle, the "proximal end" and "distal end" of any component of a medical device are defined. "Axial direction" generally refers to the length of the medical device during delivery, while "radial direction" generally refers to the direction of the medical device that is not parallel to its "axial direction." Based on this principle, the "axial direction" and "radial direction" of any component of a medical device are defined. "Circumferential direction" refers to the circumferential direction, that is, the axial direction surrounding a tubular structure or cylinder.

[0025] Example 1

[0026] Please see Figure 1 The present disclosure provides a thrombectomy device 1, including a thrombectomy bracket 10, a connecting tube 20 and a traction wire 30, wherein the distal end of the connecting tube 20 is connected to the proximal end of the thrombectomy bracket 10 and the distal end of the traction wire 30 is connected to the thrombectomy bracket 10.

[0027] The thrombectomy bracket 10 has a grid structure, comprising multiple grids 11, each grid 11 including multiple interconnected poles 111. The thrombectomy bracket 10 can be formed by braiding and shaping braided wire, or by cutting and shaping hollow tubing. The braided wire can be nickel-titanium alloy wire, stainless steel wire, or other metal wire. The hollow tubing can be nickel-titanium alloy tubing, stainless steel tubing, or other metal tubing, or it can be a polymer tubing.

[0028] The stent 10 is radially compressible, compressible to a loading size under a restraining force (radial compressive force on the stent 10 or axial tensile force applied to both ends of the stent 10) to facilitate loading the stent 10 into a delivery sheath (described below) for delivery into the patient's blood vessel. The stent 10 is self-expanding, expanding radially when the restraining force on the stent 10 is removed. For example, the stent 10 can radially expand and expand radially after the delivery sheath fitted onto the stent 10 is withdrawn from the stent 10.

[0029] Please see Figure 1 and Figure 2 The thrombectomy stent 10 has an inner cavity 12 and includes a proximal cutting portion 13, which is a circumferentially closed ring structure. The cutting portion 13 has a circumferentially closed opening 131 communicating with the inner cavity 12. (See also...) Figure 3 When the thrombectomy bracket 10 is not restrained by external force and is in a radially extended state, the projection of the cutting part 13 on the plane A perpendicular to the longitudinal central axis of the thrombectomy bracket 10 is circular.

[0030] Please return again. Figure 1 and Figure 2 The cutting portion 13 includes a distal end 132 and a proximal end 133, with an axial distance between them. A first straight line B extending axially along the thrombectomy stent 10 and passing through the distal end 132 of the cutting portion 13, and a second straight line C passing through the distal end of the thrombectomy stent 10 and the proximal end 133 of the cutting portion 13, lie in the same plane P1. When the thrombectomy stent 10 is located within the blood vessel and the restraining force acting on the thrombectomy stent 10 is removed, the thrombectomy stent 10 can self-expand and radially unfold, thereby allowing the cutting portion 13 to adhere to the vessel wall.

[0031] During the thrombectomy process using the thrombectomy device 1, the cutting portion 13 of the thrombectomy stent 10 is first positioned distal to the thrombus. The restraining force on the thrombectomy stent 10 is then released, causing the stent 10 to self-expand, thus bringing the cutting portion 13 into contact with the vessel wall. Because the cutting portion 13 is a circumferentially closed ring structure, it can conform to the vessel wall in a 360° circumferential direction. A pulling force is simultaneously applied to the traction wire 30 and the connecting tube 20 to drive the thrombectomy stent 10 proximally, thereby cutting the thrombus on the vessel wall. The thrombus cut off by the cutting portion 13 enters the lumen 12 of the thrombectomy stent 10 through the opening 131 and is captured, thus being removed from the body by the thrombectomy stent 10.

[0032] During the cutting process of the cutting section 13, the thrombectomy stent 10 is driven by the connecting tube 20 to cut the thrombus. During this process, the proximal end 133 is subjected to a proximal driving force F1 from the connecting tube 20, and simultaneously to a distal resistance F2 from the thrombus, where F1 is greater than F2. At the same time, the connecting tube 20 also generates a proximal driving force F3 on the distal end 132, but F3 is less than F1. Simultaneously, the distal end 132 is subjected to a distal resistance F4 from the thrombus, where F3 is less than F4. This results in a resultant force on the distal end 132 pointing from the proximal end to the distal end, while the resultant force on the proximal end 133 points from the distal end to the proximal end. Thus, the cutting section 13 is subjected to axial forces in opposite directions. Without other opposing forces, the cutting section 13 is stretched axially and contracts in the width direction, causing the projection of the cutting section 13 onto the plane A perpendicular to the axis of the thrombectomy stent 10 to appear as... Figure 4 The elliptical shape shown prevents the cutting section 13 from effectively cutting the blood vessel wall by disengaging it along its minor axis. Therefore, the traction wire 30 is used to reduce or counteract the axial tension on the cutting section 13.

[0033] Please refer to the following: Figure 1 and Figure 2In one embodiment, the traction wire 30 is a flexible component and is a metal wire. The traction wire 30 can be a nickel-titanium alloy wire, a cobalt-chromium-nickel alloy wire, a stainless steel wire, or other metal wire. The traction wire 30 can also be a polymer wire with a certain degree of flexibility.

[0034] Please see Figure 1 and Figure 2 The bolt retrieval bracket 10 is provided with a connection point 112 and a restraint point 113, which are circumferentially separated from the connection point 112. The connection point 112 and the restraint point 113 can be located at the intersection of two connected net rods 111 of the bolt retrieval bracket 10, or they can be located on the rod body between the two ends of the net rod 111, that is, the connection point 112 and the restraint point 113 are part of the rod body of the net rod 111.

[0035] exist Figure 1 and Figure 2 In the illustrated embodiment, connection point 112 is located at the distal end 132, meaning that connection point 112 and distal end 132 are at the same location, such that the axial distance between connection point 112 and distal end 132 is zero. Furthermore, both connection point 112 and restraint point 113 are located within plane P1.

[0036] In one embodiment, the traction wire 30 includes a drive segment 31 and a connecting segment 32. One end of the drive segment 31 is fixedly connected to a connecting point 112, and the other end extends in a straight line to a restraint point 113 and is movably connected to the restraint point 113. The distal end of the connecting segment 32 is connected to the end of the drive segment 31 connected to the restraint point 113, and the proximal end extends axially. The drive segment 31 and the connecting segment 32 are not on the same straight line. The drive segment 31 is movably connected to the restraint point 113 so that when the connecting segment 32 is pulled, the drive segment 31 can be tightened, thereby driving the thrombectomy bracket 10 to deform. The movable connection method is not limited; any method that allows the drive segment 31 to be tightened when the connecting segment 32 is pulled is acceptable. For example, the drive segment 31 is wound around a mesh 111.

[0037] In one embodiment, the drive segment 31 and the connecting segment 32 are an integral structure, that is, one end of a wire is fixedly connected to the connecting point 112 and then extends radially to the binding point 113 and is movably connected to the binding point 113, and then is compressed axially and extends out from the opening 131.

[0038] When the connecting segment 32 is pulled proximally, the driving segment 31 is tightened. The two ends of the driving segment 31 pull the thrombectomy stent 10 at the connection point 112 and the restraint point 113, respectively. This causes the thrombectomy stent 10 to undergo a certain degree of radial contraction at the connection point 112 and the restraint point 113. Since the cutting part 13 is a circumferentially closed ring structure, the radial contraction at the connection point 112 and the restraint point 113 will cause the cutting part 13 to expand radially on both sides in a direction perpendicular to the extension direction of the line connecting the connection point 112 and the restraint point 113. This reduces the degree to which the radial dimension of the opening 131 is reduced due to the axial distance between the proximal end 133 and the distal end 132 caused by the traction of the connecting tube 20 on the proximal end 133. This helps to keep the cutting part 13 in a state of adhering to or close to the vessel wall, thereby improving the thrombectomy efficiency.

[0039] In this embodiment, the connection point 112 and the distal end 132 are the same location, which makes it easier to transmit the force to the cutting part 13 when the connecting section 32 is pulled, so that the cutting part 13 deforms accordingly and the phenomenon of detachment from the blood vessel wall caused by the stretching effect is reduced.

[0040] In this embodiment, the binding point 113 is located directly below the connection point 112, that is, the axial distance between the binding point 113 and the connection point 112 is zero.

[0041] Understandably, in other embodiments, the connection point 112 may not coincide with the distal end 132, and the axial distance between the restraint point 113 and the connection point 112 may not be zero. It is only necessary to tighten the drive section 31 to pull the thimble-removing bracket 10 to radially contract at the restraint point 113 and the connection point 112, thereby causing the opening 131 to expand radially in different directions, thus mitigating the degree to which the opening 131 is axially stretched and the radial dimension is reduced.

[0042] In this embodiment, the connection point 112 and the restraint point 113 are located in the same plane, which can prevent the thrombectomy stent 10 from twisting and deforming due to the radial inward compressive forces at the connection point 112 and the restraint point 113 not being in the same plane. This can also prevent the mesh structure at the connection point 112 and the restraint point 113 from twisting and deforming, thereby preventing the cutting part 13 from twisting and deforming. As a result, during the thrombectomy process, it is beneficial to keep the cutting part 13 in contact with or close to the vessel wall.

[0043] Understandably, in other embodiments, the connection point 112 and the restraint point 113 may not be located in the same plane, but the circumferential distance between the connection point 112 and the restraint point 113 should be small to avoid twisting of the thrombectomy bracket 10. Alternatively, in other embodiments, the connection point 112 and the restraint point 113 are located on the same side of the plane, and the vertical distances from the connection point 112 and the restraint point 113 to the plane P1 are equal. This also allows the radially inward compressive force on the thrombectomy bracket 10 at the connection point 112 and the restraint point 113 to be located in the same plane, thereby preventing twisting deformation of the thrombectomy bracket 10 and the cutting part 13.

[0044] Please see Figure 5 The thrombectomy stent 10 includes, from far to near, a first segment L1, a second segment L2, and a third segment L3.

[0045] Please see Figure 5 The first segment L1 is conical and has a mesh structure. The smaller diameter end of the first segment L1 is located at the distal end, and the larger diameter end is located at the proximal end. The proximal end of the first segment L1 with the larger diameter is connected to the second segment L2. The first segment L1 has a conical inner cavity, and the larger diameter end of the first segment L1 is the open end, while the smaller diameter end is the closed end. This closed end is the closed end of the thrombectomy stent 10.

[0046] Please see Figure 5 The second segment L2 has a grid structure and is cylindrical with an inner cavity open at both ends. The distal end of the second segment L2 is connected to the proximal end of the first segment L1. The end of the second segment L2 furthest from the first segment L1 is connected to the third segment L3.

[0047] Please refer to the following: Figure 5 and Figure 6 The third segment L3 has a grid structure, and the cutting part 13 is located within the third segment L3. The proximal end of the third segment L3 is connected to the second segment L2. When the third segment L3 is unfolded into a planar shape, it forms an isosceles triangle. The third segment L3 includes a pointed corner portion at the proximal end and a wavy portion at the distal end (not shown in the figure). The pointed corner portion is the proximal end portion 133 of the cutting part 13, and the distal end portion 132 of the waist of the isosceles triangle is the distal end portion 132 of the cutting part 13.

[0048] The proximal end portion 133 of the cutting portion 13 is composed of Figure 6The pointed portion shown is formed by wrapping, that is, the proximal end 133 is a pointed structure pointing to the proximal end, so that the opening 131 of the cutting part 13 is elliptical or approximately elliptical. When the thrombectomy stent 10 passes through the venous valve, the cutting part 13 can play a guiding role, thereby facilitating the passage of the thrombectomy stent 10 through the venous valve and avoiding the cutting part 13 from scratching the venous valve.

[0049] Please see Figure 2 The thrombectomy bracket 10 also includes a collar 14, which is connected to the proximal end 133 of the cutting section 13 via a connecting rod 15.

[0050] Please see Figure 2 The connecting tube 20 is a hollow tubular structure. The distal end of the connecting tube 20 is connected to the collar 14, thereby connecting to the proximal end 133 of the cutting section 13 via the collar 14 and the connecting rod 15. The connecting tube 20 extends proximally from its connection with the collar 14, allowing force to be applied to the thrombectomy stent 10. This pushes the thrombectomy stent 10 to the distal end of the thrombus during thrombectomy, and pulls the connecting tube 20 proximally to move the thrombectomy stent 10 along the vessel wall and cut the thrombus. Simultaneously, the connecting segment 32 of the traction wire 30 is pulled proximally to reduce the radial reduction of the opening 131 due to the stretching of the connecting tube 20.

[0051] Please see Figure 1 and Figure 2The thrombectomy device 1 also includes a delivery sheath 40, which is a tubular structure slidably fitted onto the connecting tube 20. The delivery sheath 40 is used to load the thrombectomy stent 10 and transport it within the patient's blood vessel. During loading the thrombectomy stent 10, the delivery sheath 40 is manipulated to move relative to the thrombectomy stent 10, causing the delivery sheath 40 to fit onto the thrombectomy stent 10. This radially compresses the thrombectomy stent 10 to the loading size and places it within the lumen of the delivery sheath 40 for easy delivery within the patient's blood vessel. During loading the thrombectomy stent 10, a tensile force is applied to the thrombectomy stent 10 through the connecting tube 20, allowing the thrombectomy stent 10 to be compressed and loaded within the lumen of the delivery sheath 40. After the delivery sheath 40 delivers the thrombectomy stent 10 to the target site (e.g., the cutting portion 13 is located distal to the thrombus), the delivery sheath 40 is slid proximally relative to the thrombectomy stent 10 or the thrombectomy stent 10 is pushed out of the delivery sheath 40 via the connecting tube 20 to release the thrombectomy stent 10 from the delivery sheath 40, thereby removing the radial compressive force applied by the delivery sheath 40 to the thrombectomy stent 10. During the process of sliding the delivery sheath 40 proximally to release the thrombectomy stent 10, the thrombectomy stent 10 is fixed by the connecting tube 20 to prevent the thrombectomy stent 10 from being driven by the delivery sheath 40 and moving synchronously with it, thereby allowing the thrombectomy stent 10 to move relative to the delivery sheath 40 and be released from the lumen of the delivery sheath 40. After the radial binding force of the delivery sheath 40 on the thrombectomy stent 10 is removed, the thrombectomy stent 10 can expand radially to a radially extended state, so that the cutting part 13 fits against the blood vessel wall. When the driving force is applied to the thrombectomy stent 10 through the connecting tube 20 and the traction wire 30 to move the thrombectomy stent 10 proximally, the cutting part 13 can cut the thrombus on the blood vessel wall.

[0052] Please see Figure 1 and Figure 2 In one embodiment, the proximal end of the connecting segment 32 of the traction wire 30 extends proximally out of the body along the inner cavity of the delivery sheath 40 to facilitate the operator's manipulation of the traction wire 30, thereby applying a driving force to the thrombectomy bracket 10 through the traction wire 30.

[0053] In another embodiment, the proximal end of the connecting segment 32 of the traction wire 30 may extend proximally out of the body along the inner lumen of the connecting tube 20.

[0054] Please see Figure 2 and Figure 7 The thrombectomy device 1 also includes a handle 50, and the proximal end of the connecting tube 20 is fixedly connected to the handle 50. The connecting section 32 of the traction wire 30 slidably passes through the interior of the handle 50 and exits from the proximal end of the handle 50.

[0055] Specifically, please refer to Figure 7 In this embodiment, the handle 50 includes a grip 51 and a connector 52.

[0056] Please see Figure 7 The gripper 51 is a hollow cylindrical structure that extends axially for easy gripping by the operator. The distal end of the gripper 51 is connected to the connector 52. The connector 52 has a shaft hole that extends axially and passes through both the proximal and distal ends of the connector 52. The gripper 51 and connector 52 can be connected by a threaded connection, a snap-fit ​​connection, or other detachable connection methods. When the connector 52 is connected to the gripper 51, the shaft hole of the connector 52 communicates with the inner cavity of the gripper 51. The connecting section 32 of the traction wire 30 passes through the handle 50 along the shaft hole of the connector 52 and the inner cavity of the gripper 51, allowing the operator to pull the connecting section 32 during throttle removal to tighten the drive section 31.

[0057] Please refer to the following: Figure 2 and Figure 7 The proximal end of the connecting tube 20 is fixedly connected to the connector 52 or the gripper 51.

[0058] Please see Figure 7 The handle 50 is detachably connected to the delivery sheath 40 via a connector 52. In one embodiment, the connector 52 is threadedly connected to the proximal end of the delivery sheath 40. When the connector 52 is separated from the delivery sheath 40, the delivery sheath 40 can slide relative to the thrombectomy bracket 10 under external force to load or release the thrombectomy bracket 10. During thrombectomy, there is an axial gap between the distal end of the delivery sheath 40 and the proximal end of the thrombectomy bracket 10, thereby positioning the thrombectomy bracket 10 outside the delivery sheath 40 and allowing for axial displacement.

[0059] During thrombectomy, the operator moves the handle 50 to synchronously move the connecting tube 20, thus driving the thrombectomy stent 10 proximally within the blood vessel. Since the handle 50 is connected to the delivery sheath 40, the delivery sheath 40 is driven by the handle 50 and moves proximally along with it. This ensures that the distal end of the delivery sheath 40 maintains an axial distance from the proximal end of the thrombectomy stent 10, preventing the distal end of the delivery sheath 40 from compressing the thrombectomy stent 10 and affecting the thrombectomy effect. Furthermore, during thrombectomy, the portion of the traction wire 30 located within the delivery sheath 40 is isolated from the vessel wall, preventing damage to the vessel wall from the traction wire 30.

[0060] Second Embodiment

[0061] Please see Figure 8A , Figure 8B and Figure 9The difference between this embodiment and the first embodiment is that the driving segment 31 is a ring structure, which overlaps or wraps around the connection point 112 and the restraint point 113, and the driving segment 32 surrounds the longitudinal central axis of the thrombectomy stent 10. The connection segment 32 is connected to the driving segment 31, and when the connection segment 32 is stretched proximally, the driving segment 31 can be tightened, so that the driving segment 31 applies a radial compressive force to the thrombectomy stent 10. The radially compressed part of the thrombectomy stent 10 deforms radially inward, so that the cutting part 13 expands radially on both sides in a direction perpendicular to the extension direction of the line connecting the connection point 112 and the restraint point 113. This reduces the degree to which the radial dimension of the opening 131 is reduced due to the axial distance between the proximal end 133 and the distal end 132 caused by the traction of the connecting tube 20 on the proximal end 133. This helps to keep the cutting part 13 in a state of adhering to or close to adhering to the blood vessel wall, thereby improving the thrombectomy efficiency.

[0062] Furthermore, the drive segment 31 surrounds the thrombectomy stent 10. When the traction wire 30 applies traction force, the traction wire 30 radially compresses the thrombectomy stent 10, which can reduce the radial dimension of the thrombectomy stent 10 and avoid damage to the vessel wall when the thrombectomy stent 10 is used for thrombectomy in vessels with small inner diameters.

[0063] In one embodiment, the drive section 31 and the connecting section 31 are integral structures formed by silk threads. One end of the silk thread is formed with a collar. One end of the silk thread overlaps or wraps around the thrombectomy bracket 10 to form the drive section 31 surrounding the longitudinal central axis of the thrombectomy bracket 10. The other end passes through the collar and extends axially out of the inner cavity of the thrombectomy bracket 10 to form the connecting section 32.

[0064] Please see Figure 8A and Figure 10 In one embodiment, the thrombectomy stent 10 further includes a protective sleeve 60, which is fitted onto the drive section 31. The outer diameter of the protective sleeve 60 is larger than the wire diameter of the drive section 31. Therefore, compared with the traction wire 30, the protective sleeve 60 is less sharp. During the thrombectomy process, the part of the drive section 31 located outside the thrombectomy stent 10 is not in direct contact with the blood vessel wall because it is fitted with the protective sleeve 60 with a larger outer diameter. Therefore, the drive section 31 with a smaller wire diameter and a relatively sharp wire diameter can be prevented from directly contacting the blood vessel wall and damaging the blood vessel wall.

[0065] The protective sleeve 60 has a certain degree of flexibility, so it can be bent and deformed to surround the outside of the thrombec bracket 10.

[0066] In one embodiment, the protective sleeve 60 includes an inner layer 61 and an outer layer 62. The inner layer 61 can be a tubular metal layer, and the material of the inner layer 61 can be stainless steel, nickel-titanium, or other metal materials. When the protective sleeve 60 is fitted onto the driving section 31, it can prevent the protective sleeve 60 from being cut by the driving section 31. The outer layer 62 can be a tubular polymer layer, for example, the material of the outer layer 62 can be polyester, thereby increasing the flexibility of the protective sleeve 60 and effectively reducing the sharpness of the protective sleeve 60, preventing the protective sleeve 60 from damaging the blood vessel wall.

[0067] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0068] The above description discloses only preferred embodiments of the present invention and should not be construed as limiting the scope of the present invention. Therefore, equivalent variations made in accordance with the claims of the present invention are still within the scope of the present invention.

Claims

1. A thrombus removal device, characterized in that, include: A thrombectomy stent, the thrombectomy stent having an inner cavity, the thrombectomy stent including a cutting portion located at the proximal end, the cutting portion having a circumferentially closed opening communicating with the inner cavity, the cutting portion including a distal end and a proximal end having an axial distance; A connecting tube is connected to the proximal end of the thrombectomy bracket; The traction wire has its distal end connected to the thrombectomy bracket. When the traction wire is subjected to a traction action pointing towards its proximal end, the traction wire applies a radial compressive force to the thrombectomy bracket.

2. The thrombectomy device as described in claim 1, characterized in that, The thrombectomy bracket has a connection point and a restraint point. The restraint point and the connection point are circumferentially separated. The connection point is located on the far side of the distal end or at an axial distance of zero from the distal end. The restraint point is located on the far side of the proximal end. The traction wire includes a drive segment and a connecting segment connected to the drive segment. Both the drive segment and the connecting segment are straight segments. One end of the drive segment away from the connecting segment is fixedly connected to the connection point, and the other end extends to the restraint point and is movably connected to the restraint point. The connecting segment extends proximally from the point of connection with the drive segment. When the connecting segment is pulled proximally, the drive segment tightens, causing the thrombectomy bracket to be radially compressed.

3. The thrombectomy device as described in claim 2, characterized in that, The drive section and the connecting section are an integral structure formed by silk threads. One free end of the silk thread is fixedly connected to the connecting point, and the silk thread extends along the binding point and can be movably overlapped or wrapped around the binding point. Then it extends axially and extends out of the inner cavity of the thrombectomy bracket, thereby forming the drive section and the connecting section that are not on the same straight line.

4. The thrombectomy device as described in claim 2, wherein the connection point and the restraint point are both located in the same plane.

5. The thrombectomy device as described in claim 2, characterized in that, The traction wire includes a drive section and a connecting section connected to the drive section. The drive section has a ring structure and overlaps or wraps around the thrombectomy bracket. The drive section surrounds the longitudinal central axis of the thrombectomy bracket. When the connecting section is pulled proximally, the drive section tightens, causing the thrombectomy bracket to be radially compressed.

6. The thrombectomy device as described in claim 5, characterized in that, The drive section and the connecting section are an integral structure formed by silk threads. One end of the silk thread forms a collar, and one end of the silk thread overlaps or wraps around the thrombectomy bracket to form a drive section surrounding the longitudinal central axis of the thrombectomy bracket. The other end passes through the collar and extends axially out of the inner cavity of the thrombectomy bracket to form the connecting section.

7. The thrombectomy device as described in claim 1, characterized in that, The retrieval device also includes a protective sleeve, which is fitted onto the traction wire.

8. The thrombectomy device as described in claim 7, characterized in that, The protective sleeve includes an inner layer and an outer layer. The inner layer is made of a metallic material, and the outer layer is made of a flexible material.

9. The thrombectomy device as described in claim 1, characterized in that, The thrombectomy device also includes a handle, the proximal end of the connecting tube is fixedly connected to the handle, and the proximal end of the traction wire slidably passes through the interior of the handle and exits from the proximal end of the handle.

10. The thrombectomy device as described in claim 9, characterized in that, The thrombectomy device further includes a delivery sheath slidably fitted onto the connecting tube. The delivery sheath is detachably connected to the handle. The proximal end of the traction wire extends from the inner cavity of the delivery sheath into the interior of the handle and protrudes from the proximal end of the handle. When the delivery sheath is separated from the handle, it can slide relative to the thrombectomy bracket under external force, thereby loading or releasing the thrombectomy bracket. When the handle is connected to the delivery sheath, there is an axial gap between the distal end of the delivery sheath and the proximal end of the thrombectomy bracket.

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