Thrombectomy device

Abstract

The application relates to a thrombus taking device. The thrombus taking device comprises a thrombus taker and an elastic piece, the elastic piece is arranged in a space surrounded by the thrombus taker, the proximal end of the elastic piece is fixedly connected with the proximal end of the thrombus taker, the distal end of the elastic piece is fixedly connected with the distal end of the thrombus taker, the elastic piece is elastic, and the elastic piece can make the distal end of the thrombus taker and the proximal end of the thrombus taker close to each other when the thrombus taker is in a compressed state. The restoring force of the elastic piece in the application makes the distal end of the thrombus taker and the proximal end of the thrombus taker close to each other, avoids the distance between the proximal end of the thrombus taker and the distal end of the thrombus taker from increasing too much, reduces the degree of contraction of the thrombus taker in the radial direction, ensures that the thrombus taker can closely adhere to the inner wall of a blood vessel, and improves the success rate of dragging a thrombus into a microcatheter.

Description

Technical Field

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

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

[0003] Acute ischemic stroke (AIS, commonly known as cerebral infarction) is a neurological injury caused by the sudden blockage of blood flow to the brain, leading to localized ischemia and necrosis of brain tissue. AIS is the most common type of stroke and a leading cause of death and disability among middle-aged and elderly individuals. Acute stroke caused by large vessel occlusion is particularly dangerous, with high mortality and disability rates. Once a stroke occurs, it causes immense physical and psychological harm to the patient and places a heavy burden on their family and society.

[0004] Currently, the main clinical treatment for ischemic stroke is mechanical thrombectomy. Mechanical thrombectomy involves delivering a thrombectomy device to the lesion site, using the device to grasp the thrombus and remove it from the body. However, during the retraction of the current thrombectomy device into the catheter, external forces act on the device, causing it to elongate axially and contract radially. This prevents the device from adhering tightly to the vessel wall, making the thrombus more prone to detachment. Summary of the Invention

[0005] Therefore, it is necessary to provide a thrombectomy device that can reduce the degree of radial contraction of the thrombectomy device and ensure that it can fit tightly against the inner wall of the blood vessel.

[0006] The thrombectomy device includes a thrombectomy tool and an elastic element. The elastic element is disposed within the space enclosed by the thrombectomy tool. The proximal end of the elastic element is fixedly connected to the proximal end of the thrombectomy tool, and the distal end of the elastic element is fixedly connected to the distal end of the thrombectomy tool. The elastic element is elastic, and when the thrombectomy tool is in a compressed state, the elastic element can bring the distal end of the thrombectomy tool and the proximal end of the thrombectomy tool closer to each other.

[0007] The thrombectomy device includes a grabbing part for grabbing thrombi, and the elastic element includes a flat section and a plurality of spiral sections connected to the flat section. The flat section is directly opposite the grabbing part and is connected between two adjacent spiral sections.

[0008] The thrombectomy device further includes a proximal support, a middle support, and a distal support arranged sequentially from the proximal end to the distal end. The middle support is connected between the proximal support and the distal support. The grasping part is located on the middle support. The flattening section is located inside the middle support. The spiral section is located inside the proximal support and the distal support.

[0009] In its natural state, the elastic element extends spirally in the axial direction.

[0010] The elastic element includes a body and a puncture member connected to the body, the puncture member being capable of penetrating the thrombus.

[0011] The angle between the puncture member and the main body is an acute angle.

[0012] The puncture member is fixedly connected to the outer surface of the body.

[0013] The puncture member is sleeved on the outer surface of the main body, and the puncture member can rotate around the main body.

[0014] The elastic element includes two or more helical lines that extend spirally toward each other in the axial direction.

[0015] The proximal ends of the two or more spirals are closely fitted together and fixedly connected to the proximal end of the thrombectomy device, and the distal ends of the two or more spirals are closely fitted together and fixedly connected to the distal end of the thrombectomy device.

[0016] In its natural state, a containment space is formed between the two or more spirals.

[0017] The restoring force of the elastic element in this application brings the distal and proximal ends of the thrombectomy device closer together, preventing the distance between the proximal and distal ends of the thrombectomy device from increasing too much, reducing the degree of radial contraction of the thrombectomy device, ensuring that the thrombectomy device can closely adhere to the inner wall of the blood vessel, and improving the success rate of dragging the thrombus into the microcatheter. Attached Figure Description

[0018] Figure 1 for Figure 1 This is a schematic diagram of the thrombectomy device provided in the first embodiment of this application, which captures thrombi in human blood vessels.

[0019] Figure 2 This is a cross-sectional view of the thrombectomy device provided in the first embodiment of this application in its natural state.

[0020] Figure 3 This is a cross-sectional view of the thrombectomy device provided in the first embodiment of this application under compressed conditions.

[0021] Figure 4 This is a three-dimensional structural diagram of the thrombectomy device in the first embodiment of this application.

[0022] Figure 5 This is a three-dimensional structural diagram of a thrombectomy device with another angle, as shown in the first embodiment of this application.

[0023] Figure 6 This is a schematic diagram of the unfolded thrombectomy device in the first embodiment of this application.

[0024] Figure 7 for Figure 6 A magnified view of point X in the middle.

[0025] Figure 8 for Figure 6 Enlarged diagram of point XX in the middle.

[0026] Figure 9 This is a cross-sectional schematic diagram of the thrombectomy device provided in the second embodiment of this application.

[0027] Figure 10 This is a cross-sectional schematic diagram of the thrombectomy device in the second embodiment of this application.

[0028] Figure 11 This is a cross-sectional schematic diagram of the thrombectomy device provided in the third embodiment of this application.

[0029] Figure 12 This is a schematic diagram of the elastic element in the third embodiment of this application.

[0030] Figure 13 This is a cross-sectional schematic diagram of the thrombectomy device provided in the fourth embodiment of this application.

[0031] Figure 14 This is a cross-sectional schematic diagram of the thrombectomy device in the fourth embodiment of this application.

[0032] Figure 15 This is a cross-sectional schematic diagram of the thrombectomy device provided in the fifth embodiment of this application.

[0033] Figure 15a For this application Figure 15 A magnified structural diagram of point I in the middle.

[0034] Figure 16 This is a cross-sectional view of the puncture component in the thrombectomy device provided in the fifth embodiment of this application.

[0035] Figure 17 This is a cross-sectional view of the puncture component in the thrombectomy device provided in the fifth embodiment of this application from another angle.

[0036] Figure 18 This is a cross-sectional schematic diagram of the thrombectomy device provided in the sixth embodiment of this application.

[0037] Figure 19 This is a schematic diagram of the elastic element in the thrombectomy device provided in the sixth embodiment of this application.

[0038] Figure 20 This is a schematic diagram of the elastic element in the thrombectomy device provided in the seventh embodiment of this application. Detailed Implementation

[0039] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0040] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

[0041] In the field of interventional medical devices, "distal" is defined as the end furthest from the operator during surgery, and "proximal" is defined as the end closest to the operator during surgery. "Axial" refers to the direction parallel to the line connecting the center of the distal and proximal ends of the medical device, and "radial" refers to the direction perpendicular to the aforementioned axial direction.

[0042] In this embodiment of the invention, "radial force" refers to the force required to deform the medical device in the radial direction. The smaller the force required to deform the medical device in the radial direction, the smaller the radial force, and the easier it is for the medical device to be compressed or expanded radially towards its central axis; the larger the force required to deform the medical device in the radial direction, the larger the radial force, and the more difficult it is for the medical device to be compressed or expanded radially towards its central axis.

[0043] First Embodiment

[0044] Please see Figures 1 to 3 , Figure 1 A schematic diagram of the thrombectomy device provided in the first embodiment of this application capturing thrombi in human blood vessels; Figure 2 This is a cross-sectional view of the thrombectomy device provided in the first embodiment of this application in its natural state. Figure 3 This is a cross-sectional view of the thrombectomy device provided in the first embodiment of this application under compressed conditions. Figure 2 and Figure 3 The structure of the thrombus removal device has been simplified.

[0045] In this embodiment, the thrombectomy device 1 includes a microcatheter 10, a push-pull wire 20, a thrombectomy device 30, a contrast ring 40, and an elastic element 50. The microcatheter 10 has a hollow tubular structure and houses the push-pull wire 20 and the thrombectomy device 30. The microcatheter 10 is used to deliver the thrombectomy device 30 to the thrombus 200 in the blood vessel 100 and to release the thrombectomy device 30. The distal end of the push-pull wire 20 is fixedly connected to the proximal end of the thrombectomy device 30. The push-pull wire 20 can slide inside the microcatheter 10 and drive the entire thrombectomy device 30 to slide relative to the microcatheter 10.

[0046] In this embodiment, the elastic member 50 extends into the interior of the thrombectomy device 30, and the elastic member 50 is located within the space enclosed by the thrombectomy device 30. The distal end of the elastic member 50 is fixedly connected to the distal end of the thrombectomy device 30, and the proximal end of the elastic member 50 is fixedly connected to the proximal end of the thrombectomy device 30. Specifically, as... Figure 2 The proximal end of the thrombectomy device 30 covers the proximal end of the elastic element 50. A contrast ring 40 wraps around and covers the outer surface of the proximal end of the thrombectomy device 30, securing the proximal end of the thrombectomy device 30 to the proximal end of the elastic element 50. Correspondingly, the distal end of the thrombectomy device 30 covers the distal end of the elastic element 50. The contrast ring 40 wraps around and covers the outer surface of the distal end of the thrombectomy device 30, securing the distal end of the thrombectomy device 30 to the distal end of the elastic element 50. The elastic element 50 is made of a metallic material. The elastic element 50 extends spirally in the axial direction, forming a spiral shape, thus giving it elasticity.

[0047] In this embodiment, the push-pull wire 20 and the elastic element 50 are integrally formed. The sliding of the push-pull wire 20 along the microcatheter 10 also causes the elastic element 50 to slide. In other embodiments, the push-pull wire 20 and the elastic element 50 are two different components, as long as they can be fixedly connected.

[0048] In this embodiment, during the process of the thrombectomy device 1 transitioning from its natural state to its compressed state, the proximal and distal ends of the thrombectomy device 30 move away from each other, and the distance between the proximal and distal ends of the thrombectomy device 30 gradually increases. The thrombectomy device 30 as a whole contracts radially and elongates axially. The increased distance between the proximal and distal ends of the thrombectomy device 30 causes the elastic element 50 to deform and stretch axially. At this time, the elastic element 50 has a restoring force to return to its original shape. This restoring force can bring the distal and proximal ends of the thrombectomy device 30 closer together, preventing the thrombectomy device 30 from stretching too far axially. Figures 1 to 3 The operation process and the specific function of the elastic element 50 in this embodiment are described as follows:

[0049] The microcatheter 10 and the thrombectomy device 30 disposed within the microcatheter 10 are moved to the target location within the blood vessel 100. The thrombectomy device 30 is exposed outside the microcatheter 10, with at least a portion of the thrombectomy device 30 radially corresponding to the thrombus 200 on the inner wall of the blood vessel 100. The thrombectomy device 30 expands under its own radial expansion force. At least a portion of the outer surface of the thrombectomy device 30 contacts the thrombus 200 on the inner wall of the blood vessel 100, and a portion of the thrombus 200 becomes embedded within the thrombectomy device 30. Then, the push-pull wire 20 is operated to withdraw the thrombectomy device 30 back into the microcatheter 10, while the thrombus is pulled back into the catheter under the radial expansion force of the thrombectomy device 30. Under the retraction force of the thrombectomy device 30, the proximal end of the thrombectomy device 30 moves away from the distal end, causing the thrombectomy device 30 to contract. The restoring force of the elastic element 50 brings the proximal and distal ends of the thrombectomy device 30 closer together, preventing the distance between them from increasing too much and reducing the degree of radial contraction. This ensures that the thrombectomy device 30 can closely adhere to the inner wall of the blood vessel 100, increasing the success rate of pulling the thrombus 200 into the microcatheter 10. Furthermore, once the thrombus 200 enters the thrombectomy device 30, the spirally extending elastic element 50 increases the contact area with the thrombus 200, restricting its movement, preventing it from detaching, and improving the thrombectomy device 30's ability to retrieve the thrombus.

[0050] Please refer to it again. Figure 3 When the thrombectomy device 30 is under compression, the restoring force of the elastic element 50 is at its maximum when it is straightened. The axial length of the elastic element 50 when it is straightened is equal to the maximum axial length between the proximal and distal ends of the thrombectomy device 30.

[0051] Please see Figures 4 to 6 , Figure 4 This is a three-dimensional structural diagram of the thrombectomy device in the first embodiment of this application; Figure 5 This is a three-dimensional structural diagram of a thrombectomy device at another angle, as shown in the first embodiment of this application. Figure 6 This is a schematic diagram of the unfolded thrombectomy device according to the first embodiment of this application. In this embodiment, the thrombectomy device 30 can be formed by first laser-cutting a metal tube (such as a NiTi alloy tube) with shape memory effect and superelasticity, then molding it with a mold, and finally heat-treating it to set its shape. Alternatively, the thrombectomy device 30 can be formed by first cutting a metal sheet with shape memory effect and superelasticity, then molding it with a mold, and finally heat-treating it to set its shape. Alternatively, the thrombectomy device 30 can be formed by first weaving a metal wire with shape memory effect and superelasticity, then molding it with a mold and heat-treating it to set its shape. Alternatively, the thrombectomy device 30 can also be made of a highly elastic polymer material. The above-mentioned suitable materials are well known to those skilled in the art and will not be described in detail here.

[0052] In this embodiment, the thrombectomy device 30 employs a self-expanding stent structure. The thrombectomy device 30 includes a proximal stent 31, a mid-stent 32, and a distal stent 33 arranged sequentially from proximal to distal. The mid-stent 32 connects the proximal stent 31 and the distal stent 33. The mid-stent 32 is located in the middle portion of the overall thrombectomy device 30. In this embodiment, the proximal stent 31, mid-stent 32, and distal stent 33 are integrally formed. The proximal stent 31 supports the overall mid-stent 32 and distal stent 33. The mid-stent 32 captures the thrombus. The distal stent 33 gathers the thrombus, preventing it from dislodging. In other embodiments, the proximal stent 31, mid-stent 32, and distal stent 33 may be different components, as long as the proximal stent 31, mid-stent 32, and distal stent 33 can be fixedly connected to form an integral stent.

[0053] In this embodiment, the central support 32 includes a first link 324 and a second link 325 arranged at intervals. The proximal end of the first link 324 is connected to the proximal support 31. The distal end of the second link 325 is connected to the distal support 33. The first link 324 and the second link 325 extend in a circumferential curve on the circumferential surface of the thrombectomy device 30. A circumferential curve extension refers to an extension along the circumferential surface of the thrombectomy device 30 that resembles a curve along a circumference, and the direction of the curve extension is neither parallel to the longitudinal central axis of the thrombectomy device 30 nor along the circumferential direction of the thrombectomy device 30. The curve extension includes one or more of the following: arc, broken line, straight line, etc. This design, with the first link 324 and the second link 325 extending in a circumferential curve on the circumferential surface of the thrombectomy device 30, allows the proximal stent 31 and the distal stent 33 to bend and approach each other along the circumferential direction of the first link 324 and the second link 325. This gives the thrombectomy device 30 a spiral-like extension shape from proximal to distal, improving its bending performance. When the thrombectomy device 30 is in a curved blood vessel, its spiral-like extension shape can bend and deform, conforming well to the curved blood vessel. The thrombectomy device 30 can closely fit the inner wall of the curved blood vessel, effectively preventing thrombus dislodgement.

[0054] The following provides a detailed explanation of the structure of the proximal support 31, the middle support 32, and the distal support 32 of the thrombectomy device 30. Please refer to [link / reference]. Figure 6The proximal support 31 includes a first support rod 311 and a first grid unit 312 arranged sequentially. The proximal ends of the first support rods 311 converge at the proximal end of the proximal support 31, the other parts of the first support rods 311 extend outward, and the distal end of the first support rod connects to the distal end of the first grid unit 312. In this embodiment, the first support rod 311 and the first grid unit 312 are integrally formed. The width of the first support rod 311 is 0.1mm-0.5mm. The width refers to the length between the two farthest endpoints. In this embodiment, there are two first support rods 311, and the two first support rods 311 are symmetrically distributed about the central axis of the thrombectomy device 30, so that external forces are uniformly and symmetrically transmitted to the first grid unit 312 and the central support 32 of the thrombectomy device 30 via the two first support rods 311. In other embodiments, there is one first support rod 311.

[0055] Please see Figure 6 and Figure 7 , Figure 7 for Figure 6 Enlarged schematic diagram at point X. The width of the first support rod 311 is greater than the width of the rods at other different locations on the entire thrombectomy device 30; that is, the width of the first support rod 311 is the largest. Specifically, the width of the first support rod 311 is greater than the width of the middle support 32, and the width of the first support rod 311 is greater than the width of the distal support 33. The stiffness of the first support rod 311 is greater than the stiffness of other different locations on the thrombectomy device 30. The first support rod 311 is less prone to deformation than other different parts of the thrombectomy device 30, and can maintain its shape while effectively transmitting external forces to other different locations on the thrombectomy device 30.

[0056] In this embodiment, the width of the first support rod 311 gradually increases along the axial direction from the distal end to the proximal end, resulting in greater stiffness and making it more difficult to deform. This design ensures that the portion of the first support rod 311 near the proximal end has greater stiffness and is less prone to bending, thus preventing bending of the first support rod 311 from affecting the retrieval of the thrombectomy device 30.

[0057] In this embodiment, the first grid unit 312 in the proximal stent 31 is symmetrical about the central axis of the thrombectomy device 30. The first grid unit 312 can uniformly receive the force transmitted through the push-pull wire 20 and the first support rod 311, ensuring the radial support force of the proximal stent 31 after it is released from the microcatheter 10. In other embodiments, the first grid unit 312 in the proximal stent 31 may not be symmetrical about the central axis of the thrombectomy device 30, as long as the radial support force of the proximal stent 31 is guaranteed.

[0058] Regarding the central support 32, in this embodiment, the central support 32 includes a first grasping portion 321, a second grasping portion 322, a third grasping portion 323, a first connecting rod 324, a second connecting rod 325, and a third connecting rod 326. The first grasping portion 321, the second grasping portion 322, and the third grasping portion 323 are arranged sequentially from proximal to distal. The first connecting rod 324, the third connecting rod 326, and the second connecting rod 325 are arranged sequentially from proximal to distal. Figure 6 In the middle, the first capture part 321 is set between two adjacent first grid cells 312 in the proximal support 31.

[0059] The proximal end of the first link 324 is fixedly connected to the proximal support 31 at the distal end of the first grid cell 312. In this embodiment, the first link 324 is fixedly connected to the converging portion of the first grid cell 312 at the distal end. In other embodiments, the first link 324 may also be fixedly connected to the non-converging portion of the first grid cell 312.

[0060] In this embodiment, the distal end of the first connecting rod 324 is fixedly connected to the second grasping part 322. In this embodiment, there are two first connecting rods 324, arranged opposite to each other. The proximal end of the third connecting rod 326 is fixedly connected to the second grasping part 322, and the distal end of the third connecting rod 326 is fixedly connected to the third grasping part 323. The proximal end of the second connecting rod 325 is fixedly connected to the third grasping part 323, and the distal end of the second connecting rod 325 is fixedly connected to the distal support 33.

[0061] In this embodiment, the projections of the first grasping portion 321 and the second grasping portion 322 onto the plane perpendicular to the longitudinal central axis of the thrombectomy device 30 only partially overlap. Furthermore, the projections of the distal ends of the first grasping portion 321 and the distal ends of the second grasping portion onto the plane perpendicular to the longitudinal central axis of the thrombectomy device are spaced apart. This design allows the thrombectomy device 30 to simultaneously grasp thrombi at different positions on its circumference, thus improving the grasping effect of the thrombectomy device 30. Specifically, in conjunction with... Figure 6 In some embodiments, the first link 324 is inclined and bent on the circumferential surface of the retrieval device 30 relative to the positive direction of the X-axis. In other embodiments, the first link 324 may be inclined and bent in other directions on the circumferential surface of the retrieval device 30 to improve the retrieval effect of the retrieval device 30.

[0062] In this embodiment, the first link 324, the third link 326, and the second link 325 are arranged sequentially from proximal to distal in the axial direction. Each of the first link 324, the third link 326, and the second link 325 is arc-shaped and extends in a circumferential curve on the circumferential surface of the thrombectomy device 30. Among the distal ends of the first grasping portion 321, the third grasping portion 323, and the second grasping portion 322, at least two adjacent distal ends of the grasping portions are spaced apart on the projection of their distal ends onto a plane perpendicular to the longitudinal central axis of the thrombectomy device. This allows the thrombectomy device 30 to simultaneously grasp thrombi at different positions on its circumferential surface, thereby improving the grasping effect of the thrombectomy device 30. In other embodiments, at least two adjacent distal ends of the first grasping portion 321, the third grasping portion 323, and the second grasping portion 322 are all spaced apart on the projection of their distal ends onto a plane perpendicular to the longitudinal central axis of the retrieval device. This further offsets the positions of the distal ends of the first grasping portion 321, the third grasping portion 323, and the second grasping portion 322 on the circumferential surface of the retrieval device 30, thereby improving the grasping effect of the retrieval device 30.

[0063] Compared to the case where the connecting rods are parallel along the axial direction, in this embodiment, the first connecting rod 324, the third connecting rod 326, and the second connecting rod 325 extend in a circumferential curve on the circumferential surface of the thrombectomy device 30, giving the first connecting rod 324, the third connecting rod 326, and the second connecting rod 325 good bending deformation ability in the axial direction. The proximal stent 31, the middle stent 32, and the distal stent 33 can easily bend towards each other. During the process of passing through the curved blood vessel 100, the proximal stent 31, the middle stent 32, and the distal stent 33 can fit well into the curved blood vessel 100, avoiding the thrombus from detaching from the thrombectomy device 30 due to the thrombectomy device 30 not fitting into the inner wall of the blood vessel 100.

[0064] Specifically Figure 6 In this embodiment, the first link 324, part of the third link 326, and part of the second link 325 are inclined and bent downward along the circumference of the thrombectomy device 30 relative to the positive direction of the X-axis. In other embodiments, the first link 324, the third link 326, and the second link 325 may also be inclined and bent along different or partially the same directions on the circumference of the thrombectomy device 30, so as to achieve better bending performance of the thrombectomy device 30.

[0065] In this embodiment, some of the first connecting rods 324 and some of the third connecting rods 326 are parallel to each other. Parallelism means that while some of the first connecting rods 324 and some of the third connecting rods 326 are parallel to each other, some of the first connecting rods 324 and some of the third connecting rods 326 are not parallel. Specifically, in this embodiment, the third connecting rod 326 includes a straight section 3261 and an inclined section 3262. The inclined section 3262 is parallel or approximately parallel to the first connecting rod 324. The straight section 3261 is not parallel to the first connecting rod 324, but is parallel to the X-axis. This design increases the distance between the second grasping portion 322 and the third grasping portion 323, and increases the opening size of the second grasping portion 322 and the third grasping portion 323, facilitating the entry of thrombi through the opening between the second grasping portion 322 and the third grasping portion 323, thereby improving the performance of the thrombectomy device 30 in grasping thrombi.

[0066] In this embodiment, a portion of the first link 324, a portion of the second link 325, and a portion of the third link 326 are parallel to each other, making it easy for the proximal support 31 and the distal support 33 to bend and extend in the same direction. The phrase "a portion of the first link 324, a portion of the second link 325, and a portion of the third link 326 are parallel" means that while some of the first link 324, the second link 325, and the third link 326 are parallel to each other, at least some of them are not parallel. In this embodiment, the second link 325 is arched, and a portion of the second link 325 is inclined upwards along the positive X-axis. This portion of the second link 325 is parallel or approximately parallel to the first link 324. This design increases the distance between the first grasping portion 321, the second grasping portion 322, and the third grasping portion 323, and also increases the size of the openings in these portions, facilitating the entry of thrombi through these openings and improving the thrombectomy device 30's thrombus-grabbing performance. In other embodiments, portions of the first link 324, the second link 325, and the third link 326 may be nearly parallel to each other, allowing the proximal stent 31 and the distal stent 33 to easily bend and extend in the same direction.

[0067] A virtual connection exists on the circumferential surface of the thrombectomy device 30 between the distal end of the first link 324 and the proximal end of the second link 325. The first link 324, the virtual connection, and the second link 325 can form a spiral around the longitudinal central axis of the thrombectomy device 30, allowing the thrombectomy device 30, composed of the proximal support 31 and the distal support 33, to have a spiral-like shape that is easy to bend. In other embodiments, the first link 324, the virtual connection, and the second link 325 can form a curve around the longitudinal central axis of the thrombectomy device 30 that resembles a spiral shape.

[0068] In this embodiment, there are two first links 324, and the two first links 325 are arranged opposite to each other. Correspondingly, there are two second links 325 and two third links 326, which are arranged opposite to each other.

[0069] A virtual connection exists between one of the first links 324 and one of the second links 325. A virtual connection also exists between the other first link 324 and the other second link 325. This creates two spirals around the longitudinal central axis of the thrombectomy device, formed by the first link 324, the virtual connection between the first link 324 and the second link 325, and the second link 325 itself. These two spirals are not connected. The formation of two spirals in the thrombectomy device 30 further improves its bending and deformation performance, making it easier to bend and better conform to the curved blood vessel, thus closely adhering to the inner wall of the curved blood vessel and effectively preventing thrombus detachment. In other embodiments, the thrombectomy device 30 may also form only one spiral, allowing it to bend and deform along the spiral direction. In other embodiments, the thrombectomy device 30 may form three or more spirals, specifically designed to achieve the effect of easy bending and close adherence to the inner wall of the blood vessel.

[0070] In this embodiment, a first virtual connection line 327 exists between the distal end of the first link 324 and the proximal end of the third link 326 on the circumferential surface of the thrombectomy device 30. A second virtual connection line 328 also exists between the distal end of the third link 326 and the proximal end of the second link 325 on the circumferential surface of the thrombectomy device 30. The first link 324, the first virtual connection line 327, the third link 326, the second virtual connection line 328, and the second link 325 can form a spiral line around the longitudinal central axis of the thrombectomy device 30. This design allows the thrombectomy device 30, composed of the proximal support 31, the middle support 32, and the distal support 33, to have a spiral-like shape, making it easy to bend.

[0071] In other embodiments, the central stent 32 may include only the first link 324 and the second link 325, so that the thrombectomy device 30 can fit well into the curved blood vessel 1000.

[0072] The shapes of the first link 324, the second link 325, and the third link 326 are described below. In this embodiment, the first link 324 is generally inclined downward relative to the positive X-axis. A portion of the second link 325 is inclined downward relative to the positive X-axis. The portion of the second link 325 inclined relative to the positive X-axis is parallel or approximately parallel to the first link 324. The shape of the second link 325 is partially the same as that of the first link 324. The second link 325 is arched, with a portion of it inclined upward along the positive X-axis, this portion being parallel or approximately parallel to the first link 324. The other portion of the second link 325 is inclined downward along the positive X-axis.

[0073] The third link 326 includes a straight section 3261 and an inclined section 3262. The proximal end of the straight section 3261 is fixedly connected to the second grasping part 322, the distal end of the straight section 3261 is fixedly connected to the proximal end of the inclined section 3262, and the distal end of the inclined section 3262 is fixedly connected to the third grasping part 323. The inclined section 3262 is parallel or approximately parallel to the first link 324, and the extension direction of the straight section 3261 is parallel to the X-axis. This increases the distance between the second grasping part 322 and the third grasping part 323, and increases the size of the opening between the second grasping part 322 and the third grasping part 323, facilitating the entry of thrombi through the opening between the second grasping part 322 and the third grasping part 323, thereby improving the performance of the thrombectomy device 30 in grasping thrombi.

[0074] The first link 324, the second link 325, and the third link 326 have the same shape, which facilitates the arrangement of the proximal support 31, the middle support 32, and the distal support 33, ensuring that the thrombectomy device 30 as a whole has good bending performance while maintaining the overall structural arrangement of the thrombectomy device 30. In other embodiments, the first link 324, the second link 325, and the third link 326 may have the same shape, as long as the first link 324, the second link 325, and the third link 326 can achieve a circumferential spiral extension tendency of the overall thrombectomy device 30 and have good bending performance.

[0075] Please see Figure 6 and Figure 8 , Figure 8 for Figure 6 An enlarged schematic diagram at point XX. With all other conditions remaining constant, the width of the proximal end of the first link 324 is greater than the width of the middle portion of the first link 324. This increases the strength of the first link 324 at its proximal end, making it less prone to breakage than the middle portion. The width of the distal end of the first link 324 is also greater than the middle portion, making it even less prone to breakage. Correspondingly, the second link 325 and the third link 326 have similar configurations, which will not be elaborated upon here.

[0076] In this embodiment, the proximal end of the first link 324 is rounded to avoid stress concentration at the proximal end of the first link 324, which could easily lead to breakage. The distal ends of the first link 324, the proximal and distal ends of the second link 325, and the proximal and distal ends of the third link 326 are also rounded.

[0077] Please refer to it again. Figure 6 The widths of the first link 324, the second link 325, and the third link 326 are all greater than the width of the net pole in the distal support 33, and the widths of the first link 324, the second link 325, and the third link 326 are less than the width of the first support rod 311 in the proximal support 31. This arrangement makes the strength of the first link 324, the second link 325, and the third link 326 greater than the strength of the net pole in the distal support 33, and less than the strength of the first support rod 311. This makes the first link 324, the second link 325, and the third link 326 easy to bend and deform, while having good strength and not easy to break.

[0078] The following describes the first arrest section 321, the second arrest section 322, and the third arrest section 323. Please refer to the following again. Figures 4 to 6 The first capturing section 321 includes a first sub-capturing member 3211 and a second sub-capturing member 3212 spaced apart. Each of the first sub-capturing member 3211 and the second sub-capturing member 3212 includes two mesh rods. The proximal ends of the two mesh rods are connected to the mesh rod portions of adjacent first mesh rod units, and the distal ends of the two mesh rods converge, with the converging portion suspended in the air. When the thrombectomy device 30 is released in the blood vessel, it is squeezed by the blood vessel 100, causing the proximal portions of the two mesh rods to compress radially, expanding the converging portion of the distal ends of the two mesh rods outward, facilitating the first capturing section's capture of the thrombus. Correspondingly, the second capturing section 322 and the third capturing section 323 are similar in shape to the first capturing section 321. Each of the second capturing section 322 and the third capturing section 323 includes two capturing members, each consisting of two mesh rods. The near ends of these poles are fixedly connected to the pole units in the central support 32; the far ends of the poles converge in the air.

[0079] In this embodiment, the first sub-grabbing member 3211 and the second sub-grabbing member 3212 in the first grasping portion 321 partially overlap on the projection of at least one plane containing the longitudinal central axis of the thrombectomy device 30. Specifically, a portion of the first sub-grabbing member 3211 and a portion of the second sub-grabbing member 3212 are aligned, and the distance from the distal end of the first sub-grabbing member 3211 to the proximal end of the thrombectomy device 30 is greater than the distance from the distal end of the second sub-grabbing member 3212 to the proximal end of the thrombectomy device 30. During the retraction of the first grasping portion 321 into the microcatheter 10, the two opposing grasping members are compressed into the microcatheter 10 without overlapping each other, reducing the thickness of the first grasping portion 321 during compression into the microcatheter 10, thus facilitating the retraction of the first grasping portion 321 into the microcatheter 10. Correspondingly, the two capture elements in the second capture section 322 and the two capture elements in the third capture section 323 also have similar shapes to the two capture elements in the first capture section 321, with the second capture section 322 and the third capture section 323 being convenient to enter the microcatheter 10.

[0080] In this embodiment, the distal end of the first grasping portion 321 is wrapped with developing dots, and the distal end of the third grasping portion 323 is also wrapped with developing dots. In other embodiments, the distal end of the second grasping portion 322 may also be wrapped with developing dots.

[0081] The structure of the distal stent 33 is described below. The distal stent 33 comprises multiple evenly arranged grid cells. When the thrombectomy device 30 is deployed, the grid cells are approximately rhomboid in shape, and adjacent grid cells are interconnected. The openings of the grid cells in the distal stent 33 are smaller than the openings of the grid cells in the central stent, allowing the distal stent 33 to intercept and contain thrombi within the thrombectomy device 30, preventing thrombus dislodgement.

[0082] Second Embodiment

[0083] Please see Figure 9 and Figure 10 , Figure 9 This is a cross-sectional schematic diagram of the thrombectomy device provided in the second embodiment of this application; Figure 10 This is a cross-sectional schematic diagram of the thrombectomy device in the second embodiment of this application. The thrombectomy device 1a provided in this embodiment is basically the same as that in the first embodiment, except that in this embodiment, the elastic element 50a and the push-pull wire 20a are not integrally formed. The elastic element 50a is elastic and is formed of a polymer material. The proximal end of the elastic element 50a is fixedly connected to the distal end of the push-pull wire 20a. Specifically, the distal end of the push-pull wire 20a is provided with a fixing ring 21a, and the elastic element 50a is fixedly connected to the fixing ring 21a. Specifically, the elastic element 50a and the fixing ring 21a are wrapped and bound together.

[0084] In this embodiment, the thrombectomy device 1a further includes a connecting ring 60a. The distal end of the connecting ring 60a is fixedly connected to the distal end of the thrombectomy device 30a. Specifically, the elastic element 50a is wrapped and bound together with the connecting ring 60a. In this embodiment, the elastic element 50a can pass through the opening of the connecting ring 30a and be bound and fixed to the connecting ring 60a. Because the elastic element 50a is elastic, there is no need to form a spiral structure in the axial direction to ensure the elasticity of the elastic element 50a. This arrangement can reduce the density of the radial components of the thrombectomy device, making it easier to insert the thrombectomy device into the sheath.

[0085] Third Embodiment

[0086] Please see Figure 11 and Figure 12 , Figure 11 This is a cross-sectional schematic diagram of the thrombectomy device 1b provided in the third embodiment of this application; Figure 12 This is a schematic diagram of the elastic element in the third embodiment of this application. The thrombectomy device 1b provided in this embodiment is basically the same as that in the first embodiment, except that in this embodiment, the elastic element 50b includes a flattening section 51b and a spiral section 52b connected to the flattening section 51b. In the axial direction, the flattening section 51a is directly opposite the grasping portion 320b of the central support 32b. Specifically, the grasping portion 320b includes a first grasping portion 321b, a second grasping portion 322b, and a third grasping portion 323b. The flattening section 51a corresponds to the first grasping portion 321b, the second grasping portion 322b, and the third grasping portion 323b in the thrombectomy device, respectively. The flattened section 51a is straight and extends axially, which avoids interference with the first grasping portion 321b, the second grasping portion 322b, and the third grasping portion 23b, and prevents the flattened section 51a from becoming entangled in the first grasping portion 321b, the second grasping portion 322b, and the third grasping portion 23b, thus affecting the deployment of the thrombectomy device in the blood vessel. In other embodiments, the grasping portion 320b may include only the first grasping portion 321b, or only the first grasping portion 321b and the second grasping portion 322b, depending on whether the grasping portion 320b can perform the function of grasping the thrombus.

[0087] In this embodiment, multiple helical segments 52b correspond to the proximal stent 31b and the distal stent 33b, respectively. These multiple helical segments 52b possess a restoring force capable of returning to their original shape after axial stretching, ensuring the elasticity of the overall elastic element 50b. Simultaneously, the multiple helical segments 52b increase the contact area with the thrombus, preventing thrombus detachment.

[0088] In this embodiment, the flat section 51b is connected between two adjacent spiral sections 51b, so that after the thrombus enters the part corresponding to the flat section 51b in the thrombectomy device 30b, it is blocked by the adjacent spiral section 52b and is not easy to move, thereby improving the effect of the thrombectomy device 30b in preventing the thrombus from falling off.

[0089] Fourth embodiment

[0090] Please see Figure 13 and Figure 14 , Figure 13 This is a cross-sectional schematic diagram of the thrombectomy device provided in the fourth embodiment of this application; Figure 14 This is a cross-sectional schematic diagram of the thrombectomy device in the fourth embodiment of this application. The thrombectomy device 1c provided in this embodiment is basically the same as that in the first embodiment, except that in this embodiment, the elastic element 50c includes a main body 51c and a plurality of puncture elements 52c fixedly connected to the main body 51c. The main body 51c extends axially. The plurality of puncture elements 52c are arranged at intervals in the main body 51c and are staggered in the circumferential direction. During the capture of thrombi, a single puncture element 52c can pierce the thrombus, fix the thrombus, and prevent the thrombus from falling out of the thrombectomy device 30c. Moreover, the plurality of puncture elements 52c can increase the contact area between the elastic element and the thrombus, and the plurality of adjacent puncture elements 52c can clamp the thrombus with each other, further improving the effect of preventing thrombus dislodgement.

[0091] In this embodiment, the angle between each puncture element 52c and the axis of the main body 51c is an acute angle, combined with Figure 13 The extension direction of the main body is parallel to the extension direction of the X-axis. The angle between each puncture element 52c and the axis of the main body is an acute angle, the same as the angle between each puncture element 52c and the positive direction of the X-axis. During the process of the thrombeclet 30c being compressed into the microcatheter 10c, the puncture element 52c can approach the main body 51c in a clockwise direction with the connection point with the main body 51c as the base point, thus smoothly entering the microcatheter 10c and ensuring that the microcatheter 10c can smoothly retrieve the thrombus and the thrombeclet 30c. To avoid the puncture element 52c being obtuse, which could easily abut against the inner wall of the microcatheter 10c or get stuck at the opening of the microcatheter 10c, thus hindering the entry of the thrombeclet 30c into the microcatheter.

[0092] Fifth embodiment

[0093] Please see Figures 15 to 17 , Figure 15 This is a cross-sectional schematic diagram of the thrombectomy device provided in the fifth embodiment of this application; Figure 16 This is a cross-sectional view of the puncture component in the thrombectomy device provided in the fifth embodiment of this application; Figure 17 This is a cross-sectional view of the puncture member in the thrombectomy device provided in the fifth embodiment of this application from another angle. The thrombectomy device 1d provided in this embodiment is basically the same as that in the fourth embodiment, except that in this embodiment, the puncture member 52d is sleeved on the outer surface of the main body 51d. Specifically, the puncture member 52d is sleeved on the outer surface of the main body 51d through its own opening, and then the puncture member 52d is compressed to reduce the opening of the puncture member 52d, thereby preventing the puncture member 52d from falling off.

[0094] In this embodiment, the main body 51d is provided with a receiving groove 53d. A portion of the puncture member 52d is housed in the receiving groove 53d, and this portion of the puncture member 52d is limited in the axial direction by the inner wall of the receiving groove 53d, allowing the puncture member 52d to rotate only around the outer surface of the main body 51d. The puncture member 52d increases the contact area with the thrombus, improving the thrombus capture effect and preventing thrombus detachment. Furthermore, the puncture member 52d can rotate in accordance with the curvature of the blood vessel, avoiding injury to the inner wall of the blood vessel.

[0095] Sixth Embodiment

[0096] Please see Figure 18 , Figure 18 This is a cross-sectional schematic diagram of the thrombectomy device provided in the sixth embodiment of this application; Figure 19 This is a schematic diagram of the elastic element in the thrombectomy device provided in the sixth embodiment of this application. The thrombectomy device 1e provided in this embodiment is basically the same as that in the first embodiment, except that in this embodiment, the elastic element 50e includes a first spiral 51e and a second spiral 52e, which extend and intertwine with each other. After the proximal end of the first spiral 51e and the proximal end of the second spiral 52e are tightly fitted and intertwined, they are fixedly connected to the distal end of the push-pull wire 20e and the proximal end of the thrombectomy device 30e. In the natural state, after the distal end of the first spiral 51e and the distal end of the second spiral 52e are tightly fitted and intertwined, they are fixedly connected to the distal end of the thrombectomy device 30e. The main body of the first spiral 51e (excluding the proximal and distal ends of the first spiral) and the main body of the second spiral 52e (excluding the proximal and distal ends of the second spiral) extend spirally towards each other in the axial direction, and there is a gap between them, which together form a receiving space.

[0097] During the thrombectomy process, in addition to limiting the axial extension of the thrombectomy device 30e to be too long, the elastic element can also increase the contact area with the thrombus during the thrombectomy process, so that part of the thrombus can be embedded in the receiving space between the first spiral line 51e and the second spiral line 52e, so that the thrombus is resisted by the first spiral line 51e and the second spiral line 52e and cannot be easily detached, thus preventing the thrombus from falling off.

[0098] Please see Figure 20 , Figure 20This is a schematic diagram of the elastic element in the thrombectomy device provided in the seventh embodiment of this application. The thrombectomy device in this embodiment is basically the same as that in the sixth embodiment. The difference is that the elastic element 50e includes multiple spirals 53e. Multiple spirals refer to three or more spirals. The proximal ends of the multiple spirals 53e are tightly wound and fixedly connected to the distal ends of the push-pull wire 20e. The distal ends of the multiple spirals 53e are tightly wound and fixedly connected to the distal ends of the thrombectomy device 30e. The multiple spirals 53e include a main body portion connected to its proximal and distal ends. The main body portions are all housed inside the thrombectomy device 30e and extend spirally and intersect with each other to form a housing space 54e. Thrombi that enter the housing space 54e are limited by the limiting multiple spirals 53e and are difficult to detach. Moreover, the multiple spirals 53e cooperate with the thrombectomy device 30e, and the thrombus is stuck between the thrombectomy device 30e and the multiple spirals 53e, effectively preventing the thrombus from falling off.

[0099] 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.

[0100] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A thrombus removal device, characterized in that, The thrombectomy device includes a thrombectomy device and an elastic element. The elastic element is disposed within the space enclosed by the thrombectomy device. The proximal end of the elastic element is fixedly connected to the proximal end of the thrombectomy device, and the distal end of the elastic element is fixedly connected to the distal end of the thrombectomy device. The elastic element is elastic, and when the thrombectomy device is in a compressed state, the elastic element can bring the distal end of the thrombectomy device and the proximal end of the thrombectomy device closer to each other. The thrombectomy device includes a grabbing part for grabbing thrombi, and the elastic element includes a flat section and a plurality of spiral sections connected to the flat section. The flat section is directly opposite the grabbing part and is connected between two adjacent spiral sections. The thrombectomy device further includes a proximal support, a middle support, and a distal support arranged sequentially from the proximal end to the distal end. The middle support is connected between the proximal support and the distal support. The grasping part is located on the middle support. The flattening section is located inside the middle support. The spiral section is located inside the proximal support and the distal support.

2. The thrombectomy device as described in claim 1, characterized in that, In its natural state, the elastic element extends spirally in the axial direction.

3. The thrombectomy device as described in claim 1, characterized in that, The elastic element includes a body and a puncture member connected to the body, the puncture member being capable of penetrating the thrombus.

4. The thrombectomy device as described in claim 3, characterized in that, The angle between the puncture member and the main body is an acute angle.

5. The thrombectomy device as described in claim 3, characterized in that, The puncture member is fixedly connected to the outer surface of the body.

6. The thrombectomy device as described in claim 3, characterized in that, The puncture member is sleeved on the outer surface of the main body, and the puncture member can rotate around the main body.

7. The thrombectomy device as described in claim 1, characterized in that, The elastic element includes two or more helical lines that extend spirally toward each other in the axial direction.

8. The thrombectomy device as described in claim 7, characterized in that, The proximal ends of the two or more spirals are closely fitted together and fixedly connected to the proximal end of the thrombectomy device, and the distal ends of the two or more spirals are closely fitted together and fixedly connected to the distal end of the thrombectomy device.

9. The thrombectomy device as described in claim 7 or 8, characterized in that, In its natural state, a containment space is formed between the two or more spirals.

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