Thrombectomy device

Abstract

The invention provides a thrombectomy device. The thrombectomy device comprises a thrombectomy support, a pushing rod and at least one developing wire. The thrombectomy stent comprises a tubular grid structure composed of more than two ribs which are connected with each other. The near end of the thrombectomy bracket is fixedly connected with the far end of the push rod; the at least one developing wire is arranged to be wound on the rib in one direction, and the one-way winding is winding from the near end to the far end of the thrombectomy stent or winding from the far end to the near end of the thrombectomy stent; the near end of the developing wire is fixedly connected with the pushing rod, and the far end of the developing wire is fixed to the far end of the thrombus taking device. According to the thrombectomy device provided by the invention, the developing wire is unidirectionally wound on the thrombectomy stent, so that the overall developing property of the stent is improved, the outer diameter of the stent is basically not increased, and the device can be applied to a small-size micro-catheter system; meanwhile, the near end of the developing wire is fixedly connected with the pushing rod, and the far end of the developing wire is fixed to the far end of the thrombectomy device, so that the fixing reliability of the developing wire is improved, and the risk that the developing wire falls off is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and in particular to a thrombus removal device. Background Art

[0002] Acute stroke is the third leading cause of death today and the leading cause of disability in adults. Among them, ischemic stroke accounts for about 85% of acute stroke. Ischemic stroke is mainly caused by blockage of cerebral blood vessels, which forms blood clots on the inner walls of cerebral blood vessels, preventing blood from flowing into the brain. There are currently two main treatments for acute ischemic stroke, namely drug thrombolysis and mechanical thrombectomy. Among them, drug thrombolysis is suitable for smaller thrombi, and the treatment effect for large thromboembolic emboli is not ideal. In addition, due to the narrow treatment time window of drug thrombolysis and the low vascular recanalization rate, mechanical thrombectomy has become the mainstream direction for the treatment of acute ischemic stroke. Currently, self-expanding nickel-titanium alloy thrombectomy devices are the mainstream technology on the market.

[0003] The current visualization technologies for thrombectomy devices mainly include: 1. Achieving the overall visualization purpose through the weak visualization property of the metal grid material itself (such as nickel-titanium alloy), that is, achieving the visualization purpose without adding any strong visualization materials such as platinum, tungsten and other metals. For example, the material of Codman's Revive SE thrombectomy stent is nickel-titanium alloy, and the visualization purpose is achieved through the weak visualization of the stent grid itself, and additional visualization parts are added at both ends of the thrombectomy stent. However, this visualization method is greatly limited by the width and wall thickness of the metal grid rod. When the width and wall thickness of the metal grid rod are reduced, the overall visualization effect of the stent is poor, and only the approximate position of the stent in the blood vessel can be located, but it is difficult to accurately judge more specific situations such as the degree of expansion of the stent. Due to the spatial size limitation of the intracranial blood vessels, the rod width and wall thickness of the metal grid are inevitably limited. Therefore, this visualization method is suitable for larger specifications of thrombectomy stents, such as thrombectomy stents adapted to 0.027-inch or 0.021-inch microcatheters. Second, by adding developing parts, such as developing points, developing rings or developing coils, which are generally platinum-tungsten alloy parts, to the metal mesh, the developing property of the stent can be enhanced; for example, the Solitaire thrombectomy device improves the developing property of the product by adding a platinum-tungsten developing spring to the metal mesh, but most of the thrombectomy devices that increase the developing property by hanging developing springs also face the problem of insufficient space size. For example, the smallest Solitaire thrombectomy device is only suitable for a 0.021-inch microcatheter system. The developing design with a hanging spring is not compatible with a smaller size, such as a 0.017-inch microcatheter system. Therefore, for more distal emboli, it cannot reach the lesion location, which seriously limits its scope of use and also cannot meet the overall developing requirements of the thrombectomy stent. Third, there is currently a method on the market to increase the overall developing property of the metal mesh by winding developing wires on it. Compared with the developing design with developing parts, this method can reduce the overall size of the stent to a certain extent, but the distal or proximal end of the developing wire is often fixedly connected to the stent mesh, so that the developing wire and the stent form a rigid connection, and there is a risk of the developing wire falling off due to the breakage of the welding point.

[0004] Due to size and space limitations, the thrombectomy device cannot carry too many developing parts to increase its developing ability. Therefore, it is necessary to design reasonable developing parts and their fixing methods on the bracket to enhance the overall developing effect of the thrombectomy device while having a smaller size and higher safety to meet clinical developing requirements. Summary of the invention

[0005] In view of the problems in the prior art, the object of the present invention is to provide a thrombus removal device suitable for a small-sized microcatheter system to meet clinical imaging requirements.

[0006] The embodiment of the present invention provides a thrombus removal device, comprising a thrombus removal bracket, a pushing rod and at least one developing wire;

[0007] The thrombus removal bracket comprises a tubular grid structure composed of two or more mutually connected ribs; the proximal end of the thrombus removal bracket is fixedly connected to the distal end of the pushing rod;

[0008] The at least one developing wire is configured to be unidirectionally wound on the rib, and the unidirectional winding is winding from the proximal end to the distal end of the thrombus removal bracket, or winding from the distal end to the proximal end of the thrombus removal bracket; the proximal end of the developing wire is fixedly connected to the pushing rod, and the distal end of the developing wire is fixed to the distal end of the thrombus removal device.

[0009] In some embodiments, the unidirectional winding of the at least one imaging wire on the rib includes winding from the proximal end to the distal end or from the distal end to the proximal end simultaneously along the axial and circumferential directions of the thrombectomy stent; the at least one imaging wire is spirally wound on the rib.

[0010] In some embodiments, the material of the developing wire is a platinum-tungsten alloy wire or a composite wire, the composite wire includes an inner core and an outer layer, the inner core is one or more of platinum-iridium alloy, platinum-nickel alloy, platinum-tungsten alloy, tungsten-tantalum alloy, tungsten, tantalum and gold, and the outer layer is nickel-titanium alloy.

[0011] In some embodiments, the diameter of the developing filament is 0.0010 inches to 0.0030 inches.

[0012] In some embodiments, the developing wire is configured to be wound around the ribs and form multiple winding points at the grid nodes of the tubular grid structure, and the length of the developing wire between two adjacent winding points on the same developing wire is greater than the length of the ribs between two adjacent winding points.

[0013] In some embodiments, a connecting gasket is further included. The connecting gasket is a tubular structure. At least the proximal end of the connecting gasket is sleeved on the outside of the distal end of the pushing rod. The proximal end of the thrombus removal bracket is sleeved on the outside of at least the distal end of the connecting gasket. The distal end of the pushing rod, the connecting gasket and the proximal end of the thrombus removal bracket are fixedly connected.

[0014] In some embodiments, at least one empty slot is provided on the side wall of the connection gasket, and the proximal end of the developing wire passes through the empty slot from the inner side of the proximal end of the thrombus removal bracket and is at least partially connected to the distal end of the pushing rod.

[0015] In some embodiments, the number of the empty slots is the same as the number of the developing wires, and the number of the empty slots and the number of the developing wires are both three.

[0016] In some embodiments, the outer wall of the distal end of the push rod is sleeved with a heat shrink tube, the proximal end of the developing wire passing through the empty groove is arranged between the heat shrink tube and the outer wall of the push rod, and the proximal end of the developing wire is fixedly connected to the push rod by welding, heat shrinking and / or bonding; the heat shrink tube is a polytetrafluoroethylene tube or a polyether block polyamide tube.

[0017] In some embodiments, the length of the proximal end of the developing wire fixed on the pushing rod is 1 mm to 40 mm, and the total length of the developing wire is 80 mm to 120 mm.

[0018] In some embodiments, a developing component is further included, and the distal end of the thrombus removal bracket is fixedly connected to the developing component, and the distal end of the developing wire is fixedly connected to the developing component.

[0019] In some embodiments, the developing component is a developing spring coil, and the developing wire passes through the developing spring coil and is fixedly connected to the distal end of the developing spring coil.

[0020] The thrombus removal device provided by the present invention has the following advantages:

[0021] The thrombus removal device of the present invention winds the developing wire unidirectionally on the thrombus removal stent from the proximal end to the distal end or from the distal end to the proximal end, thereby improving the overall developing property of the thrombus removal stent and substantially not increasing the outer diameter of the stent, so that the device can be applied to a smaller-sized microcatheter system; at the same time, the proximal end of the developing wire is fixedly connected to the pushing rod, and the distal end of the developing wire is fixed to the distal end of the thrombus removal device, thereby improving the reliability of the fixing of the developing wire and reducing the risk of the developing wire falling off. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Other features, objectives and advantages of the present invention will become more apparent from a reading of the detailed description of non-limiting embodiments made with reference to the following accompanying drawings.

[0023] Figure 1 is a schematic diagram of a thrombus removal device without developing wire winding provided by an embodiment of the present invention;

[0024] Figure 2 is a schematic diagram of a thrombus removal device with a developing wire wound therein according to an embodiment of the present invention;

[0025] Figure 3 yes Figure 2 The enlarged image of the area indicated by the dashed box;

[0026] Figure 4 is a schematic diagram of the distal end arrangement of a thrombus removal device according to an embodiment of the present invention;

[0027] Figure 5 is a schematic diagram of a developing coil spring according to an embodiment of the present invention;

[0028] Figure 6 is a schematic diagram of the proximal end arrangement of a thrombus removal device according to an embodiment of the present invention;

[0029] Figure 7 yes Figure 6 A schematic diagram of the structure of the connecting parts in FIG.

[0030] Figure 8 yes Figure 6 Schematic diagram of the proximal fixation method of the developing filament in.

[0031] Reference numerals:

[0032] 10 Thrombectomy Stent

[0033] 10a Proximal end of the thrombectomy stent

[0034] 11 tendons

[0035] 20 Push rod

[0036] 20b Distal end of push rod

[0037] 30 Development Silk

[0038] 40 Connectors

[0039] 50 Development unit

[0040] 50b Far end of the developing unit

[0041] 60 Connection gasket

[0042] 61 empty slots

[0043] 70 Heat shrink tubing

[0044] 80 Traction Wire

[0045] 90 Support assembly

[0046] 100 Locking parts DETAILED DESCRIPTION

[0047] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in a variety of forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that the present invention will be comprehensive and complete and fully convey the concepts of the example embodiments to those skilled in the art. In the figures, the same reference numerals represent the same or similar structures, and thus their repeated description will be omitted. "or" and "or" in the specification may both mean "and" or "or".

[0048] The following describes the implementation methods of the present application through specific examples, and those skilled in the art can easily understand other advantages and effects of the present application from the content disclosed in the present application. The present application can also be implemented or applied through other different specific implementation methods, and the details in the present application can also be modified or changed in various ways according to different viewpoints and application systems without departing from the spirit of the present application. It should be noted that the embodiments in the present application and the features in the embodiments can be combined with each other without conflict.

[0049] In the representations of the present application, the representations with reference to the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" etc. mean that the specific features, structures, materials or characteristics represented in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. Moreover, the represented specific features, structures, materials or characteristics may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples represented in the present application and the features of the different embodiments or examples, unless they contradict each other.

[0050] The present invention provides a thrombus removal device, comprising a self-expanding thrombus removal stent, a push rod and at least one developing wire, the thrombus removal stent is a tubular grid structure composed of two or more mutually connected ribs, the proximal end of the thrombus removal stent is fixedly connected to the distal end of the push rod, at least one developing wire is unidirectionally wound on the ribs, and most unidirectional windings refer to winding along the proximal end to the distal end of the thrombus removal stent, or winding along the distal end to the proximal end of the thrombus removal stent. This winding method can realize the overall development of the thrombus removal stent, and at the same time, the outer diameter of the stent is basically not increased, so that the thrombus removal device can be applied to a smaller size microcatheter system. The proximal end of the developing wire is fixedly connected to the push rod, and the distal end of the developing wire is fixedly connected to the distal end of the thrombus removal device. Compared with the technical solution in the prior art in which the developing parts are directly welded to the thrombus removal stent, the fixing method of the developing wire of the present invention is more reliable. It should be noted that the proximal end and the distal end here are relative to the operator, the end closer to the operator is the proximal end, and the end farther from the operator is the distal end.

[0051] The structure of the thrombus removal device according to a specific embodiment of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiment is not intended to limit the protection scope of the present invention.

[0052] like Figure 1 and Figure 2 As shown, an embodiment of the present invention provides a thrombus removal device, including a thrombus removal bracket 10 , a pushing rod 20 and at least one developing wire 30 .

[0053] In some embodiments of the present invention, the thrombus removal stent 10 is a tubular grid structure composed of two or more ribs 11 connected to each other; optionally, the proximal end 10a of the thrombus removal stent 10 is fixedly connected to the distal end of the pushing rod 20 by welding, bonding or crimping.

[0054] The at least one developing wire 30 is configured to be unidirectionally wound on the rib 11, and the unidirectional winding is winding from the proximal end to the distal end of the thrombus removal bracket 10, or winding from the distal end to the proximal end of the thrombus removal bracket 10; optionally, the proximal end of the developing wire 30 extends out of the proximal end of the thrombus removal bracket 10, and is fixedly connected to the pushing rod 20 by welding, heat shrinking and / or bonding. In the embodiment of the present invention, the unidirectional winding of the at least one developing wire 30 on the rib 11 is winding from the proximal end to the distal end or from the distal end to the proximal end along the axial and circumferential directions of the thrombus removal bracket 10 at the same time; and the at least one developing wire 30 is spirally wound on the rib 11 from the proximal end to the distal end of the thrombus removal bracket 10 or from the distal end to the proximal end of the thrombus removal bracket. In some embodiments of the present invention, a single developing wire is unidirectionally wound on the ribs of the thrombectomy stent from the distal end to the proximal end, or from the distal end to the proximal end. The process is simple, the operation is convenient, and the overall developing property of the thrombectomy stent is increased. In one embodiment, the same 3-20 specification stent is used. After the developing wire is wound, the outer diameter of the stent is 3.24 mm, and the outer diameter of the bare stent without the developing wire is 3.20 mm. Therefore, it is further shown that the way of winding the developing wire in the embodiment of the present invention will not increase the outer diameter of the stent, nor change the pushing property and supporting performance of the thrombectomy stent, so that the device can be applied to a small-sized microcatheter system. In another embodiment, the unidirectional winding of the developing wire includes winding along the axial direction and circumferential direction of the thrombectomy stent at the same time. This winding method can better achieve the overall development of the thrombectomy stent.

[0055] Specifically, the material of the developing wire is a metal developing material, such as a platinum-tungsten alloy wire or a composite wire (DrawnFilled Tubing, DFT), the DFT wire includes an inner core and an outer layer, the inner core is one or more of a platinum-iridium alloy, a platinum-nickel alloy, a platinum-tungsten alloy, tungsten, tantalum, a tungsten-tantalum alloy and gold, and the outer layer is a nickel-titanium alloy. Since the DFT wire contains nickel-titanium components, it has a certain superelasticity and is not easy to bend or twisted during the winding process, and is a preferred developing wire.

[0056] Optionally, the diameter of the imaging wire is 0.001 inch to 0.003 inch, and the size of the imaging wire is selected according to the size of the microcatheter that the thrombectomy stent is adapted to. Figure 3As shown, the specific winding method of the developing wire 30 is: from inside to outside or from outside to inside (relative to the inside and outside of the thrombus removal stent 10), the developing wire 30 is spirally wound around the ribs 11 of the thrombus removal stent 10 for more than 360 degrees and fixed on the ribs 11 of the thrombus removal stent 10, the developing wire 30 is wound around the ribs 11 and forms multiple winding points at the grid nodes of the tubular grid structure, and the length of the developing wire between two adjacent winding points on the same developing wire 30 is greater than the length of the ribs 11 between two adjacent winding points, that is, a certain margin is left when the developing wire 30 is wound. In this way, on the one hand, the developing wire can be stably fixed on the thrombus removal stent, and on the other hand, the developing wire has a certain redundancy while better fitting the thrombus removal stent, which can ensure that when the tubular grid of the thrombus removal stent is unfolded and released, the developing wire will not pull the metal grid, thereby avoiding the problem of reducing the supporting force of the thrombus removal stent.

[0057] like Figure 2 and Figure 3 As shown, the number of developing wires 30 in this embodiment is 3, but it is not limited thereto, and can be 1 wire or multiple wires. The 3 developing wires can realize full development of the thrombus removal stent from any angle, and the winding setting is simple. When the number of developing wires exceeds 3, the winding setting will be more complicated, increasing the process cost. This application mainly introduces the winding of 3 developing wires as an example.

[0058] Specifically, Figure 4 and Figure 5 A schematic diagram of the distal end of the thrombectomy device is shown. Figure 4 and Figure 5 As shown, the device further includes a connecting member 40 and a developing member 50, and the distal end of the thrombus removal bracket 10 is fixedly connected to the developing member 50 by welding or bonding. In one embodiment of the present invention, the distal end of the developing wire 30 extends out of the distal end of the thrombus removal bracket 10 and the interior of the developing elastic member 50 in sequence, and is fixedly connected to the distal end of the developing member 50 by welding or bonding. The developing member 50 has an inner cavity, which can accommodate the developing wire, and can specifically be a developing spring formed by spirally winding a developing metal wire, or a developing structural member formed by laser cutting a tube into a hollow structure, or a developing ring or a non-closed annular developing member, etc. Compared with the prior art in which the distal end and the proximal end of the developing wire are fixed to the bracket by welding or bonding, so that the developing wire and the bracket form a rigid connection, there is a risk of the developing wire falling off due to the breakage of the welding point, and the fixing method of the developing wire 30 adopted in this embodiment is safer and more reliable.

[0059] The connecting member 40 is a hollow tubular structure, the developing component 50 is a spring coil of a metal developing material, and preferably the distal end is a closed structure, the proximal end of the connecting member 40 is fixedly connected to the distal end of the thrombus removal bracket 10 by welding, bonding or crimping, and the distal end of the connecting member 40 is fixedly connected to the proximal end of the developing component 50 by welding or bonding; the distal end of the developing wire 30 passes through the hollow tubular structure and is fixedly connected to the developing component 50. In some embodiments, when the distal end of the developing wire 30 is fixed, the distal end of the developing wire 30 passes through the inner hole of the connecting member 40 and the inside of the developing spring coil in sequence, and is fixedly connected to the distal end 50b of the developing spring coil, and at this time, the distal end of the developing wire 30 serves as the anti-untwisting wire of the developing spring coil 50. The developing component 50 and the developing wire can be fixedly connected by laser welding or glue bonding, but it is not limited thereto. By using the developing wire as the anti-untwisting wire of the developing spring coil, the number of parts is saved, and while the developing performance of the thrombectomy device is enhanced, the distal space utilization of the thrombectomy device is improved, and the developing wire is effectively fixed at the same time; on the other hand, the distal end of the developing wire is fixed to the developing spring coil, and the developing wire itself has a certain flexibility. When the developing spring coil is extended and retracted, the developing wire also has a certain amount of extension and retraction, which can ensure that when the thrombectomy stent is deployed and released, the developing wire will not excessively pull the thrombectomy stent, thereby preventing the supporting force of the thrombectomy stent from being affected by the developing wire.

[0060] In some other embodiments of the present invention, the distal end of the thrombus retriever stent 10 is an open structure, which is different from the closed distal structure in the above-mentioned embodiments. The distal end face of the open thrombus retriever stent 10 is circular, elliptical or polygonal, and the radial dimension of the distal cross-section of the thrombus retriever stent 10 can be roughly equal to the radial dimension of the middle part of the thrombus retriever stent 10, which is not limited by the present invention.

[0061] like Figures 6 to 8 As shown, the proximal end setting of the thrombus removal bracket is shown. The proximal end of the thrombus removal bracket 10 includes a connecting gasket 60, and the connecting gasket 60 is a tubular structure. At least the proximal end of the connecting gasket 60 is sleeved on the outside of the distal end 20b of the pushing rod 20, and the proximal end 10a of the thrombus removal bracket 10 is sleeved on the outside of at least the distal end of the connecting gasket 60. The distal end 20b of the pushing rod 20, the connecting gasket 60 and the proximal end 10a of the thrombus removal bracket 10 can be fixedly connected by laser welding or bonding.

[0062] Furthermore, at least one empty groove 61 is provided on the side wall of the connection gasket 60, and the proximal end of the developing wire 30 passes through the empty groove 61 from the inner side of the proximal end of the thrombus removal bracket 10 and is at least partially connected to the distal end of the pushing rod 20. In this embodiment, the empty groove 61 is through along the distal end of the connection gasket 60, and part of the structure of the empty groove 61 does not contact the proximal end of the thrombus removal bracket 10 and the distal end of the pushing rod 20, so that the proximal end of the developing wire 30 can pass through the part of the empty groove 61, and then the developing wire 30 is fixedly connected to the pushing rod 20. Figure 7 As shown, the number of the empty slots 61 is the same as the number of the developing wires 30. The proximal end of each developing wire 30 can pass through an empty slot 61 and be fixedly connected to the push rod 20. This arrangement avoids interference between the developing wires, but the number, shape and position of the empty slots 61 are not limited thereto.

[0063] The connection gasket is set so that the welding point between it and the proximal end of the thrombus removal bracket and the push rod can avoid the position where the developing wire passes through the empty slot, thereby avoiding the problem that the developing wire is easily melted and falls off when the proximal end of the thrombus removal bracket, the connection gasket and the push rod are welded and fixed. If the connection gasket is not set, the developing wire passes through the inside of the proximal end of the thrombus removal bracket, which is easy to cause the developing wire to melt and fall off when the proximal end of the thrombus removal bracket is welded and fixed to the push rod; on the other hand, if the connection gasket is not set, the developing wire bypasses the outside of the proximal end of the thrombus removal bracket and is fixed to the push rod, which will increase the size of the proximal end of the thrombus removal bracket, which is not conducive to the overall pushing of the thrombus removal bracket. Therefore, the method of setting the connection gasket can effectively utilize the internal space of the thrombus removal bracket, reduce the cross-sectional size of the proximal end of the thrombus removal bracket, and then effectively reduce the pushing resistance. In particular, when the connection gasket with an empty slot is used, it is convenient to fix the proximal end of the developing wire with the push rod, and further reduce the size of the proximal end of the thrombus removal bracket. Preferably, the number of the empty slot and the developing wire is three, so as to achieve the ideal developing effect while minimizing the increase in the size of the thrombus removal device.

[0064] See also Figure 8After the proximal end of the developing filament 30 passes through the empty groove 61 of the connecting gasket 60, it is attached to the outer wall of the push rod 20. The outer wall of the distal end of the push rod 20 is sleeved with a heat shrink tube. The proximal end of the developing filament 30 is arranged between the heat shrink tube and the outer wall of the push rod 20. The proximal end of the developing filament 30 is fixedly connected to the push rod 20 through the heat shrink tube by heat shrinking or bonding. The heat shrink tube can be a polytetrafluoroethylene tube (PTFE) or a polyether block polyamide tube (Pebax). Optionally, the length of the proximal end of the developing filament 30 fixed to the push rod 20 by heat shrinkage is 1mm to 40mm, and the total length of the developing filament 30 is 80mm to 120mm. Sufficient margin is left at the proximal end of the developing wire 30 passing through the empty groove 61. On the one hand, it can ensure that the developing wire 30 is effectively fixed on the pushing rod 20. On the other hand, even if the metal mesh structure of the thrombus removal bracket 10 moves relatively due to potential risks when it is unfolded, the proximal end of the developing wire 30 will not escape the restriction of the heat shrink tube 70, thereby avoiding the developing wire 30 falling off and causing medical safety accidents.

[0065] like Figure 1 As shown, the thrombus removal device further includes a traction wire 80, which passes through the push rod 20 and the thrombus removal stent 10 respectively, and the traction wire 80 can slide in the hollow inner cavity of the push rod 20. The thrombus removal device further includes a support assembly 90, and the two ends of the support assembly 90 are respectively connected to the distal end of the traction wire 80 and the thrombus removal stent 10. The thrombus removal device further includes a locking component 100, which is arranged on the traction wire 80 between the distal end of the support assembly 90 and the distal end of the push rod 20. When the traction wire 80 is pulled in the proximal direction, the support assembly 90 is pulled, so that the area of ​​the thrombus removal stent where the support assembly 90 is arranged expands radially, thereby adjusting the radial support force of the stent and the overall radial size; the locking component 100 can prevent the thrombus removal stent from over-expanding when the traction wire 80 is pulled excessively.

[0066] In summary, the thrombus removal device provided by the present invention has the following advantages:

[0067] (1) The thrombus removal device of the present invention winds the developing wire unidirectionally from the proximal end to the distal end or from the distal end to the proximal end on the thrombus removal stent, thereby improving the overall developing property of the thrombus removal stent and substantially not increasing the outer diameter of the stent, so that the device can be applied to a microcatheter system of a smaller size; at the same time, the proximal end of the developing wire is fixedly connected to the pushing rod, and the distal end of the developing wire is fixed to the distal end of the thrombus removal device, thereby improving the reliability of the fixing of the developing wire and reducing the risk of the developing wire falling off;

[0068] (2) A certain amount of redundancy is left when the developing wire is wound to ensure that the developing wire does not affect the smooth release and deployment of the thrombectomy stent;

[0069] (3) The stent proximal end uses a connecting gasket transition developing wire, which effectively utilizes the internal space of the stent and reduces the pushing resistance of the stent;

[0070] (4) The proximal end of the developing filament is fixed with a heat shrink tube, which can ensure that the proximal end of the developing filament is reliably fixed and avoid the developing filament falling off and causing medical safety accidents; the distal end of the developing filament is fixedly connected to the developing component as an anti-untwisting wire, which improves the space utilization of the distal end and can also effectively fix the distal end of the developing filament.

[0071] The above contents are further detailed descriptions of the present invention in combination with specific preferred embodiments, and it cannot be determined that the specific implementation of the present invention is limited to these descriptions. For ordinary technicians in the technical field to which the present invention belongs, several simple deductions or substitutions can be made without departing from the concept of the present invention, which should be regarded as falling within the protection scope of the present invention.

Claims

1. A thrombus removal device, characterized in that: It includes a thrombectomy bracket, a pushing rod and at least one developing wire; The thrombus removal stent comprises a tubular grid structure composed of two or more ribs connected to each other; The proximal end of the thrombus removal bracket is fixedly connected to the distal end of the pushing rod; The at least one imaging wire is arranged to be unidirectionally wound on the rib, and the unidirectional winding is wound from the proximal end to the distal end of the thrombus removal stent, or from the distal end to the proximal end of the thrombus removal stent; The proximal end of the developing wire is fixedly connected to the pushing rod, and the distal end of the developing wire is fixed to the distal end of the thrombus removal device.

2. The thrombus removal device according to claim 1, characterized in that: The unidirectional winding of the at least one imaging wire on the rib includes winding from the proximal end to the distal end or from the distal end to the proximal end along the axial direction and the circumferential direction of the thrombus removal bracket at the same time; the at least one imaging wire is spirally wound on the rib.

3. The thrombus removal device according to claim 1, characterized in that: The developing wire is a platinum-tungsten alloy wire or a composite wire; the composite wire comprises an inner core and an outer layer, the inner core is one or more of platinum-iridium alloy, platinum-nickel alloy, platinum-tungsten alloy, tungsten-tantalum alloy, tungsten, tantalum and gold, and the outer layer is nickel-titanium alloy.

4. The thrombus removal device according to claim 1, characterized in that: The diameter of the developing filament is 0.0010 inch to 0.0030 inch.

5. The thrombus removal device according to claim 1, characterized in that: The developing wire is configured to be wound around the ribs and form a plurality of winding points at the grid nodes of the tubular grid structure, and the length of the developing wire between two adjacent winding points on the same developing wire is greater than the length of the ribs between two adjacent winding points.

6. The thrombus removal device according to claim 1, characterized in that: It also includes a connecting gasket, which is a tubular structure. At least the proximal end of the connecting gasket is sleeved on the outside of the distal end of the pushing rod, and the proximal end of the thrombus removal bracket is sleeved on the outside of at least the distal end of the connecting gasket. The distal end of the pushing rod, the connecting gasket and the proximal end of the thrombus removal bracket are fixedly connected.

7. The thrombus removal device according to claim 1, characterized in that: At least one empty slot is provided on the side wall of the connection gasket, and the proximal end of the developing wire passes through the empty slot from the inner side of the proximal end of the thrombus removal bracket and is at least partially connected to the distal end of the pushing rod.

8. The thrombus removal device according to claim 7, characterized in that: The number of the empty slots is the same as the number of the developing wires, and the number of the empty slots and the number of the developing wires are both three.

9. The thrombus removal device according to claim 7, characterized in that: The outer wall of the distal end of the push rod is sleeved with a heat shrink tube, the proximal end of the developing wire passing through the empty groove is arranged between the heat shrink tube and the outer wall of the push rod, and the proximal end of the developing wire is fixedly connected to the push rod by welding, heat shrinking and / or bonding; the heat shrink tube is a polytetrafluoroethylene tube or a polyether block polyamide tube.

10. The thrombus removal device according to claim 9, characterized in that: The length of the proximal end of the developing wire fixed on the pushing rod is 1mm-40mm, and the total length of the developing wire is 80mm-120mm.

11. The thrombus removal device according to claim 1, characterized in that: It also includes a developing component, the distal end of the thrombus removal bracket is fixedly connected to the developing component, and the distal end of the developing wire is fixedly connected to the developing component.

12. The thrombus removal device according to claim 11, characterized in that: The developing component is a developing spring coil, and the developing wire passes through the developing spring coil and is fixedly connected to the distal end of the developing spring coil.

Images