Thrombectomy stent and manufacturing method of net-shaped stent of thrombectomy stent

Abstract

The invention discloses a thrombectomy stent and a manufacturing method of a net-shaped stent of the thrombectomy stent, and relates to the technical field of medical instruments. The thrombectomy stent comprises a net-shaped stent, and the net-shaped stent comprises a plurality of monofilaments which are woven with one another. Wherein one ends of at least two monofilaments are wound and / or welded and / or extruded by external force to form multifilaments, and a plurality of multifilaments are mutually gathered or wound to form the head end and the tail end of the net-shaped stent. And the other ends of the plurality of monofilaments are mutually gathered or wound to form the tail end of the net-shaped bracket. The arrangement mode of the head end of the net-shaped stent is improved by winding and / or welding and / or extruding a plurality of monofilaments into multifilaments at the head end by external force. According to the structure provided by the invention, the stability and convenience of connection between the net-shaped stent and the guide wire can be improved, and the trafficability, compliance and bearable maximum propulsive force of the stent penetrating through a tortuous blood vessel are improved.

Description

[0001] This application claims priority to Chinese invention patent application number 2024111490756 filed on August 21, 2024, with the public name “A thrombectomy stent”, and claims priority to Chinese invention patent application number 2024116699912 filed on November 21, 2024, with the public name “Thrombectomy stent and method for manufacturing thrombectomy stent”, the entire contents of which are incorporated herein by reference. Technical Field

[0002] The present specification relates to the field of medical device technology, and in particular to a thrombectomy stent and a method for manufacturing a mesh stent of the thrombectomy stent. Background Art

[0003] Currently, the speed of clot removal is a key indicator in the treatment of ischemic stroke patients. There are two main treatments for intracranial thrombosis: drug thrombolysis and mechanical thrombectomy. Mechanical thrombectomy involves using a stent to remove the blocked blood vessel. Currently, the main stents used are self-expanding cutting stents and braided mesh stents.

[0004] Stent retrievers offer efficient revascularization for deep vein thrombosis (DVT) through minimally invasive interventional technology. In DVT treatment, stent retrievers deliver a metal mesh stent to the site of the thrombus via a catheter. After deployment, it engages the thrombus. The catheter is then withdrawn to remove the entire thrombus (e.g., mechanical thrombectomy devices like the AngioJet). This procedure can be combined with balloon dilatation or permanent stent placement to address venous stenosis (e.g., iliac vein compression syndrome).

[0005] For acute pulmonary embolism (PE), stent thrombectomy (such as the FlowTriever system) directly captures and removes thrombi via a pulmonary artery catheter, rapidly reducing pulmonary artery pressure and improving right heart function. Its safety and short-term efficacy have been clinically validated. Combining a stent retriever with catheter-directed thrombolysis (CDT) can enhance thrombus removal and is particularly suitable for high-risk patients who require postoperative anticoagulation to prevent recurrence. This technology significantly reduces post-thrombotic syndrome (PTS) and PE-related mortality, making it a preferred option for patients in whom traditional thrombolysis is contraindicated or ineffective.

[0006] Existing braided thrombectomy stents mostly use a single flat or single round wire design. A single flat wire design generates greater radial force during thrombectomy, making it more susceptible to embedding into thrombi and potentially damaging blood vessels, while also hindering stent expansion. A single round wire design generates less radial force than a flat wire design, minimizing vessel damage, but presents challenges navigating tortuous vessels.

[0007] The permeability and delivery capacity of thrombectomy stents in the treatment of ischemic stroke, deep vein thrombosis and pulmonary embolism still need to be further strengthened and improved. Summary of the Invention

[0008] This specification provides a thrombectomy stent and a method for manufacturing a mesh stent of the thrombectomy stent, so as to at least partially solve the above-mentioned problems existing in the prior art.

[0009] This manual adopts the following technical solutions:

[0010] This specification provides a thrombus retrieval stent, which includes a mesh stent;

[0011] The mesh stent comprises a plurality of monofilaments woven together;

[0012] One end of at least two monofilaments is wound into a multifilament, and a plurality of multifilaments are gathered together or wound into the first end of the mesh stent;

[0013] The other ends of the plurality of monofilaments are gathered together or wound to form the second end of the mesh stent.

[0014] Preferably, the other ends of at least two monofilaments can be wound into multifilaments, and a plurality of multifilaments can be gathered together or wound into the second end of the mesh stent.

[0015] Preferably, the multifilament is formed by winding one end of 2, 3 or 4 monofilaments.

[0016] Preferably, the monofilament includes flat filament and round filament;

[0017] Among the at least two monofilaments constituting the multifilament, there is at least one flat yarn.

[0018] Preferably, for any multifilament, in the at least two monofilaments constituting the multifilament, the number of round filaments is greater than or equal to the number of flat filaments.

[0019] In another aspect, this specification also provides a method for manufacturing a mesh stent for a thrombectomy stent, comprising:

[0020] Winding one end of a plurality of monofilaments into a plurality of multifilaments by winding one end of at least two monofilaments into a multifilament;

[0021] Gathering or winding the plurality of multifilaments into the head end of the mesh stent;

[0022] braiding the plurality of monofilaments;

[0023] The other ends of the multiple monofilaments are gathered or woven into the tail end of the mesh stent.

[0024] On the other hand, the present specification also provides a thrombus retrieval stent, wherein the thrombus retrieval stent includes a mesh stent;

[0025] The mesh support comprises a first end, a second end, and a mesh portion between the first end and the second end;

[0026] The mesh stent is composed of a plurality of monofilaments woven together;

[0027] The first end comprises at least one multifilament; the multifilament is formed by winding and / or welding and / or externally extruding the same end of at least two monofilaments into a multifilament;

[0028] The first end has a first end fixing portion;

[0029] The monofilaments and / or multifilaments constituting the first end are fixed to the first end fixing portion.

[0030] Preferably, the first end of the mesh stent is the head end;

[0031] The second end of the mesh support is the tail end.

[0032] Preferably, the head end of the mesh stent is formed by gathering and / or winding and / or welding and / or extruding at least one monofilament and at least one multifilament;

[0033] The tail end is formed by directly gathering and / or winding and / or welding and / or extruding one end of multiple monofilaments, or the tail end is formed by gathering and / or winding and / or welding and / or extruding multiple multifilaments, or the tail end is formed by gathering and / or winding and / or welding and / or extruding at least one monofilament and at least one multifilament.

[0034] Preferably, the number of monofilaments constituting the mesh stent is 12;

[0035] One end of three monofilaments is gathered and / or wound and / or welded and / or externally extruded into a multifilament;

[0036] One end of the three monofilaments and the three multifilaments are gathered or wound together to form the head end of the mesh stent.

[0037] Preferably, the number of monofilaments constituting the mesh stent is 12;

[0038] One end of two monofilaments is gathered and / or wound and / or welded and / or externally extruded into a multifilament;

[0039] One end of the four monofilaments and the four multifilaments are gathered or wound together to form the head end of the mesh stent.

[0040] Preferably, the mesh portion comprises a plurality of meshes woven from a plurality of monofilaments;

[0041] The spaces between the grids near the head end are larger than those between the grids near the tail end.

[0042] On the other hand, the present specification also provides a use of a thrombectomy stent in treating deep vein thrombosis, pulmonary embolism, or ischemic stroke. The thrombectomy stent is the thrombectomy stent provided in any one of the above aspects.

[0043] At least one of the above technical solutions adopted in this specification can achieve the following beneficial effects:

[0044] Based on the above-mentioned thrombus removal stent, the thrombus removal stent includes a mesh stent, and the mesh stent includes multiple monofilaments woven together. Among them, one end of at least two monofilaments is wound and / or welded and / or externally extruded into a multifilament, and the multiple multifilaments are gathered together or wound to form the head end of the mesh stent. The other ends of the multiple monofilaments are gathered together or wound to form the tail end of the mesh stent. By winding and / or welding and / or externally extruding the multiple monofilaments into a multifilament at the head end, the arrangement of the mesh stent head end is improved, thereby improving the weaving efficiency.

[0045] This specification also provides the use of the above-mentioned thrombectomy stent in treating deep vein thrombosis, pulmonary embolism or ischemic stroke.

[0046] As can be seen from the above, the structure provided by the present invention can simplify the arrangement of the mesh stent at the head end, improve the stability and convenience of the connection between the mesh stent and the guide wire, and improve the stent's passability, compliance, and maximum tolerable propulsion force when passing through tortuous blood vessels. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] The drawings described herein are used to provide a further understanding of this specification and constitute a part of this specification. The exemplary embodiments and descriptions of this specification are used to explain this specification and do not constitute an improper limitation of this specification. In the drawings:

[0048] Figure 1 A schematic structural diagram of a thrombus removal stent provided in one embodiment of the present disclosure;

[0049] Figure 2 A schematic structural diagram of a mesh support provided in one embodiment of this specification;

[0050] Figure 3A schematic structural diagram of a mesh support provided in one embodiment of this specification;

[0051] Figure 4 A partial schematic diagram of the experimental process provided in this manual;

[0052] Figure 5 A partial schematic diagram of the experimental process provided in this manual;

[0053] Figure 6 A line chart showing the experimental results of the propulsion experiment provided in this manual;

[0054] Figure 7 A schematic structural diagram of a mesh stent of a thrombectomy stent provided in one embodiment of this specification;

[0055] Figure 8 A schematic structural diagram of a mesh stent of a thrombectomy stent provided in one embodiment of this specification;

[0056] Figure 9 An overall schematic diagram of a thrombectomy system provided in accordance with one embodiment of this specification;

[0057] Figure 10 A schematic structural diagram of a grid support provided in one embodiment of this specification;

[0058] Figure 11 A schematic structural diagram of a grid support provided in one embodiment of this specification;

[0059] Figure 12 A schematic structural diagram of a grid support provided in one embodiment of this specification;

[0060] Figure 13 A schematic diagram of winding a monofilament into a multifilament according to an embodiment of the present invention;

[0061] Figure 14 A schematic diagram of winding a monofilament into a multifilament according to an embodiment of the present invention;

[0062] Figure 15 A schematic diagram of winding a monofilament into a multifilament according to an embodiment of the present specification;

[0063] Figure 16 A schematic structural diagram of a grid support provided in one embodiment of this specification;

[0064] Figure 17 A schematic cross-sectional view of one end of a mesh stent provided in accordance with an embodiment of the present disclosure;

[0065] Figure 18 A schematic cross-sectional view of one end of a mesh stent provided in accordance with an embodiment of the present disclosure;

[0066] Figure 19 A schematic structural diagram of a mesh support provided in one embodiment of this specification;

[0067] Figure 20 A schematic structural diagram of a mesh support provided in one embodiment of this specification;

[0068] Figure 21 This is a schematic flow chart of a method for manufacturing a mesh stent 1 of a thrombectomy stent according to an embodiment of the present disclosure.

[0069] Description of reference numerals:

[0070] Mesh support 1; core shaft 2; outer tube 3; developing ring 4; spring 5; housing 6; head end 11; tail end 12; multifilament 13; monofilament 14; push handle 7; mesh portion 8. DETAILED DESCRIPTION

[0071] To make the purpose, technical solutions, and advantages of this specification more clear, the technical solutions of this specification will be clearly and completely described below in conjunction with the specific embodiments of this specification and the corresponding drawings. Obviously, the embodiments described are only part of the embodiments of this specification, not all of the embodiments. Based on the embodiments in this specification, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of this application.

[0072] In the description of the present invention, it should be noted that the term "or" is generally used in a sense including "and / or", unless the content clearly indicates otherwise.

[0073] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. In addition, in the description of this application, the terms "first," "second," etc. are used only to distinguish descriptions and should not be understood to indicate or imply relative importance.

[0074] In the description of the present invention, it should be noted that the "distal end" is generally the end away from the doctor, that is, the end entering the lesion in the patient's body, and the "proximal end" is generally the end close to the doctor, that is, the end that does not enter the patient's body.

[0075] Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0076] The technical solutions provided by the embodiments of this specification are described in detail below with reference to the accompanying drawings.

[0077] Figure 1 A schematic diagram of the structure of a thrombus removal stent provided in one embodiment of the present invention is shown in FIG. Figure 1 As shown, the thrombus removal stent includes a mesh stent 1 and a developing ring 4 .

[0078] Preferably, the thrombus removal bracket further includes a core shaft 2 passing through the mesh bracket 1 and the developing ring 4, such as Figure 1 shown.

[0079] Preferably, the core shaft 2 can be connected to a guide wire to control the radial contraction and radial expansion of the mesh stent 1 .

[0080] Preferably, the thrombus removal stent includes a mesh stent 1 .

[0081] Preferably, the mesh stent 1 includes a plurality of monofilaments 14 woven together.

[0082] Preferably, the mesh stent 1 includes a head end 11, a tail end 12, and a mesh portion 8 between the head end 11 and the tail end 12. It should be emphasized that, in terms of material composition, the mesh stent 1 comprises multiple monofilaments 14, and structurally, different segments of the multiple monofilaments 14 constitute the head end 11, the mesh portion 8, and the tail end 12, respectively, which are not conflicting. The head end 11 is the first end of the mesh stent 1, and the tail end 12 is the second end of the mesh stent.

[0083] Preferably, one end of the multiple monofilaments 14 is gathered or wound into the head end 11 of the mesh bracket 1, and the other end of the multiple monofilaments 14 is gathered or wound into the tail end 12 of the mesh bracket 1, and the middle part of the multiple monofilaments 14 is woven together to form the mesh part 8 of the mesh bracket 1.

[0084] Preferably, the mesh stent 1 can be connected to a guide wire through the tail end 12 , and the guide wire can be a central control axis, that is, a core axis 2 , for controlling the expansion and contraction of the mesh stent 1 .

[0085] Preferably, the mesh stent 1 can be pushed and driven by the guide wire to move forward and backward in the catheter or the patient's blood vessel.

[0086] Preferably, when one end of multiple monofilaments 14 constitutes the head end 11 of the mesh stent 1, multiple multifilaments 13 can be wound and / or welded and / or externally extruded into multifilaments 13 by preferentially winding and / or welding and / or externally extruding one end of at least two monofilaments 14, and the multiple multifilaments 13 are gathered together or wound into the head end 11 of the mesh stent 1, and the head end 11 formed by winding multiple multifilaments 13 can extend proximally to form a long axis.

[0087] Figure 2 as well as Figure 3A partial structural diagram of a thrombus removal stent according to an embodiment of the present invention is shown in FIG. Figure 2 as well as Figure 3 As shown, at the head end 11 of the mesh stent 1, multiple single filaments 14 are preferentially wound or gathered into multiple multifilaments 13, which are then bundled by the developing ring 4. At the tail end 12 of the mesh stent 1, multiple single filaments 14 are directly bundled by the developing ring 4. The head end 11 and tail end 12 of the thrombus removal stent and the mesh portion 8 in the middle portion can be integrally formed or can be separate independent parts. If the head end 11, tail end 12 and mesh portion 8 are separate independent parts, the head end 11 and tail end 12 can be connected to the mesh portion 8 via connecting wires.

[0088] The head end 11 and / or the tail end 12 may include a connection portion connected to the core shaft, the connection portion is the middle area between the long axis and the mesh portion 8, and also includes a transition section connected to the mesh portion 8. On one side of the transition section, that is, the axis side, multiple multifilaments 13 are wound in parallel, and the multifilaments 13 do not cross each other. Alternatively, at least one multifilament 13 may be wound in parallel with a single filament, and the multifilament 13 does not cross the single filament. The other side of the transition section is the woven side, wherein the connection portion may be multiple single filaments and at least one multifilament spirally wound until the transition section. In the transition section, each multifilament is restored to a single filament and woven with the original multiple single filaments. Figure 17 and Figure 18 As shown, the connection portion can be wound with a mixture of monofilaments and multifilaments, or with multifilaments.

[0089] Preferably, when the head end 11 is formed by gathering or winding a plurality of multifilaments 13, the tail end 12 can be formed by gathering or winding the other ends of a plurality of monofilaments 14. Of course, when the other ends of the plurality of monofilaments 14 form the tail end 12 of the mesh stent 1, the other ends of the plurality of monofilaments 14 can also be preferably wound and / or welded and / or externally extruded into a multifilament 13 by the other ends of at least two monofilaments 14, and the plurality of multifilaments 13 are gathered or wound together to form the tail end 12 of the mesh stent 1.

[0090] Preferably, the multifilament 13 constituting the head end 11 of the mesh stent 1 is formed by winding one end of 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 or 16 monofilaments 14.

[0091] Preferably, the multifilament 13 constituting the tail end 12 of the mesh stent 1 is formed by winding one end of 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 or 16 monofilaments 14.

[0092] Preferably, the monofilament 14 includes flat yarn and round yarn.

[0093] Preferably, at least one flat yarn exists in the at least two monofilaments 14 constituting the multifilament 13. The multifilament 13 is the multifilament 13 constituting the head end 11 of the mesh stent 1 and / or the multifilament 13 constituting the tail end 12 of the mesh stent 1.

[0094] Preferably, for any multifilament 13 , in the at least two monofilaments 14 constituting the multifilament 13 , the number of round filaments is greater than or equal to the number of flat filaments.

[0095] Preferably, the developing ring 4 is provided at the head end 11 and / or the tail end 12 .

[0096] Further preferably, part of the structure of the head end 11 passes through the developing ring 4 , that is, the developing ring 4 is located in the middle of the head end 11 .

[0097] Figure 19 as well as Figure 20 Each of them is a schematic diagram of the structure of a mesh support provided by an embodiment of this specification, such as Figure 19 as well as Figure 20 As shown, whether it is the head end 11 composed of parallel arranged monofilaments 14 and multifilaments 13, or the tail end 12 composed of parallel wound monofilaments 14 and multifilaments 13, a developing ring 4 is provided at both the head end and the tail end, and the developing ring 4 can be provided in the middle of the head end 11.

[0098] Preferably, the other ends of at least two monofilaments 14 corresponding to any multifilament 13 constituting the head end 11 are wound into the same multifilament 13 at the tail end 12. For example, among the six monofilaments 14 numbered A, B, C, D, E, and F, one end of monofilament 14A, monofilament 14B, and monofilament 14C are wound and / or welded and / or extruded by external force to form the multifilament 13, and the other ends of monofilament 14A, monofilament 14B, and monofilament 14C are also wound and / or welded and / or extruded by external force to form the multifilament 13; one end of monofilament 14D, monofilament 14E, and monofilament 14F are wound and / or welded and / or extruded by external force to form the multifilament 13, and the other ends of monofilament 14D, monofilament 14E, and monofilament 14F are also wound and / or welded and / or extruded by external force to form the multifilament 13. By adopting this method, the force on the mesh stent 1 containing multifilaments 13 at both the head end 11 and the tail end 12 can be more concentrated, thereby improving the compliance of the mesh stent 1, which is beneficial for the mesh stent 1 to pass through tortuous blood vessels. In addition, the firmness of the mesh stent 1 can be improved, making the mesh stent 1 less likely to be concave and less likely to be flattened, thereby increasing the maximum propulsion force that the mesh stent 1 can withstand.

[0099] Preferably, the other ends of at least two monofilaments 14 corresponding to any multifilament 13 constituting the head end 11 are wound into a single multifilament 13 at the tail end 12. For example, of the four monofilaments 14 numbered A, B, C, and D, monofilament 14A and monofilament 14B are wound and / or welded and / or extruded at one end to form multifilament 13, and monofilament 14C and monofilament 14D are wound and / or welded and / or extruded at one end to form multifilament 13. However, monofilament 14A and monofilament 14C are wound and / or welded and / or extruded at the other end to form multifilament 13; and monofilament 14D and monofilament 14B are wound and / or welded and / or extruded at the other end to form multifilament 13. By adopting this method, the mesh stent 1 containing the multifilament 13 at both the head end 11 and the tail end 12 can be made stronger, making the mesh stent 1 less likely to be concave and less likely to be flattened, thereby increasing the maximum propulsion force that the mesh stent 1 can withstand, and also improving the compliance of the mesh stent 1, which is beneficial for the mesh stent 1 to pass through tortuous blood vessels.

[0100] Preferably, when the multiple monofilaments 14 constituting the mesh stent 1 form the head end 11 of the mesh stent 1, one end of at least two of the monofilaments 14 is wound into at least one multifilament 13, and the at least one multifilament 13 and one end of the remaining at least one monofilament 14 are wound together or gathered to form the head end 11 of the mesh stent 1. In other words, when the multiple monofilaments 14 constituting the mesh stent 1 form the head end 11 of the mesh stent 1, they are not all gathered or wound directly as monofilaments 14, nor are they all gathered or wound as multifilaments 13. Instead, the monofilaments 14 and multifilaments 13 coexist.

[0101] It is further preferred that multiple single filaments 14 preferentially form multifilaments 13 when forming the head end 11 of the mesh stent 1. The more single filaments 14 that are gathered or wound into the head end 11 in the form of multifilaments 13, the better the support strength of the mesh stent 1, the less likely it is to be concave or flattened, and the easier it is to pass through tortuous blood vessels.

[0102] It is further preferred that when multiple monofilaments 14 are formed into the head end 11 of the mesh stent 1, the more monofilaments 14 are directly gathered or wound into the head end 11 in the form of monofilaments 14, the better the compliance of the mesh stent 1 will be through the improvement of the present application, and the less likely it will be stuck by the blood vessel wall, thereby improving the pass rate.

[0103] To this end, this application also provides corresponding experimental data. The experimental subjects are sample 1, which is composed of monofilaments 14, and sample 2, which is composed of multifilaments 13. Among them, sample 1 is directly composed of 12 monofilaments 14, and the 12 monofilaments 14 in sample 1 are parallel to each other. Sample 2 is composed of 12 monofilaments 14, preferably combined in pairs, to form 6 multifilaments 13, which are then aggregated from the 6 multifilaments 13, and the 6 multifilaments 13 in sample 2 are parallel to each other.

[0104] This application provides the test data of the three-point bending test on the above-mentioned samples 1 and 2. Figure 4 as well as Figure 5 These are partial schematic diagrams of the experimental process provided in this manual, such as Figure 4 as well as Figure 5 As shown, three-point bending tests were performed on samples 1 and 2 using experimental equipment.

[0105] Table 1 is the sample information and process parameter table provided in this manual.

[0106] Table 1

[0107] name outer diameter length span Displacement Bending speed Sample 1 φ0.40mm 23mm 16mm 3.2mm 32mm / min Sample 2 φ0.52mm 23mm 16mm 3.2mm 32mm / min

[0108] As shown in Table 1, due to the different weaving methods, the outer diameters of Samples 1 and 2 are somewhat different, but there are no differences in other experimental parameters.

[0109] Table 2 is a test result data table of the three-point bending test provided in this specification, as shown in Table 2.

[0110] Table 2

[0111]

[0112] Among them, the flexural strength refers to the maximum stress that the material can withstand when it is bent and damaged, and the maximum bending force is the maximum load that the material can withstand before reaching the flexural strength.

[0113] As shown in Table 2, across three repeated tests, the flexural strength of Samples 1 and 2 remained virtually unchanged, but the maximum flexural force of Sample 2 was significantly higher than that of Sample 1. This suggests that preferentially weaving monofilaments 14 into multifilaments 13 and aggregating multifilaments 13 can carry greater loads and be less susceptible to damage than simply aggregating monofilaments.

[0114] This application provides test data of propulsion force tests conducted on the above-mentioned Samples 1 and 2. Table 3 is a table of test results of the propulsion force test provided in this specification.

[0115] Table 3

[0116]

[0117] Figure 6 This is a line chart showing the experimental results of the propulsion experiment provided in this manual.

[0118] As shown in Table 3 and Figure 6 It can be seen from the above that the maximum propulsion force of sample 1 is significantly lower than that of sample 2. Figure 6It can also be seen that when the propulsion force is less than 0.08N, the displacement of sample 2 is almost stable below 0.3mm, but when sample 1 is subjected to any propulsion force, the displacement is almost always above 0.6mm.

[0119] Obviously, the monofilaments 14 are preferentially woven into the multifilaments 13 , and the way of gathering the multifilaments 13 can bear a greater pushing force than the way of directly gathering the monofilaments 14 .

[0120] That is to say, compared with the method of directly gathering the monofilaments 14, the monofilaments 14 are preferably wound and / or welded and / or extruded into multifilaments 13 by external force, and then the multiple multifilaments 13 are gathered. Although the flexibility is not much different, the pushing force is significantly improved.

[0121] Preferably, the number of monofilaments 14 constituting the mesh stent 1 is 12, one end of nine monofilaments 14 is wound into three multifilaments 13, and one end of the other three monofilaments 14 and the three multifilaments 13 are gathered or wound together to form the head end 11 of the mesh stent 1.

[0122] Among them, one end of every three monofilaments 14 in the nine multifilaments 13 is wound into a multifilament 13. Of course, one end of two, three, or four multifilaments 13 in the nine multifilaments 13 can also be wound into a multifilament 13, or other combinations can be used, which is not limited in this specification.

[0123] Preferably, among the 12 monofilaments 14 , the 9 monofilaments 14 whose one ends are wound and / or welded and / or extruded by external force to form the multifilament 13 are all flat filaments.

[0124] Preferably, among the 12 monofilaments 14 , the 9 monofilaments 14 whose one ends are wound and / or welded and / or extruded by external force to form the multifilament 13 are all round filaments.

[0125] Preferably, in the mesh stent 1 , the multiple monofilaments 14 wound and / or welded and / or extruded into multifilaments 13 at one end are all flat filaments, and the monofilaments 14 not wound and / or welded and / or extruded into multifilaments 13 are all round filaments.

[0126] Preferably, in the mesh stent 1 , all the monofilaments 14 are flat filaments.

[0127] Preferably, in the mesh stent 1 , the multiple monofilaments 14 wound and / or welded and / or externally extruded at one end into the multifilament 13 are all round filaments, and the monofilaments 14 not wound into the multifilament 13 are all flat filaments.

[0128] Preferably, in the mesh stent 1 , all the monofilaments 14 are round wires.

[0129] Preferably, the number of monofilaments 14 constituting the mesh stent 1 is 12, wherein one end of 8 monofilaments 14 is wound into 2 multifilaments 13, and one end of the other 4 monofilaments 14 and the 4 multifilaments 13 are gathered or wound together to form the head end 11 of the mesh stent 1.

[0130] Among the eight multifilaments 13 , one end of every two monofilaments 14 is wound to form a multifilament 13 .

[0131] Figure 7 as well as Figure 8 A partial structural diagram of a thrombus removal stent according to an embodiment of the present invention is shown in FIG. Figure 7 as well as Figure 8 As shown, the head end 11 and the tail end 12 of the mesh stent 1 are both gathered or woven together by monofilaments 14 and multifilaments 13 to form a long axis, and the developing ring 4 is arranged outside the long axis. In other words, the head end 11 and the tail end 12 of the mesh stent 1 are bound by the developing ring 4.

[0132] Of course, one end of three, four, or five monofilaments 14 in the eight multifilaments 13 can be respectively wound into one multifilament 13, or other combinations can be used, which is not limited in this specification.

[0133] Preferably, the length of the mesh support 1 is 3 cm. Furthermore, the length error of the mesh support 1 is ±0.5 cm.

[0134] Preferably, the diameter of the mesh stent 1 is 3-5 mm. Furthermore, the diameter error of the mesh stent 1 is ±1 mm.

[0135] Preferably, the outer diameter of the developing ring 4 is 2 mm. Furthermore, the outer diameter error of the developing ring 4 is 0.5 mm.

[0136] based on Figure 1 The thrombectomy stent shown includes a mesh stent 1 comprising a plurality of interwoven monofilaments 14. At least two monofilaments 14 are wound and / or welded and / or extruded at one end to form a multifilament 13, which is then gathered or wound together to form the head end 11 of the mesh stent 1. The other ends of the monofilaments 14 are gathered or wound together to form the tail end 12 of the mesh stent 1.

[0137] As can be seen from the above, the structure provided by the present invention can simplify the arrangement of the mesh stent 1 at the tip 11, improving the stability and convenience of the connection between the mesh stent 1 and the guide wire. Moreover, by first winding and / or welding and / or externally extruding the monofilament 14 into the multifilament 13 and then forming the tip 11, the stent's passability through tortuous blood vessels, compliance, and maximum thrust force it can withstand are also improved.

[0138] Preferably, the mesh stent includes a head end, a tail end, and a mesh portion 8 between the head end and the tail end.

[0139] Preferably, the mesh portion 8 is formed by weaving together a plurality of monofilaments to form a region of multiple meshes.

[0140] Preferably, the mesh stent is composed of a plurality of monofilaments braided together.

[0141] Preferably, the head end comprises at least one multifilament, wherein the multifilament is formed by winding the same end of at least two monofilaments.

[0142] Preferably, the head end has a first end fixing portion, and the monofilaments and / or multifilaments constituting the head end are fixed to the first end fixing portion.

[0143] Preferably, the tail end has a tail end fixing portion, and the monofilament and / or multifilament constituting the tail end is fixed to the tail end fixing portion.

[0144] In this specification, the interwoven monofilaments are bundled as a monofilament or multifilament at the head end and finally fixed to the first end fixing portion. Similarly, the interwoven monofilaments are bundled as a monofilament or multifilament at the tail end and finally fixed to the tail end fixing portion.

[0145] Preferably, the developing ring 4 is sleeved on the outside of the head end 11 and / or the tail end 12 .

[0146] Preferably, the monofilament 14 is a superelastic wire or a metal wire or a braided wire with a developing function.

[0147] Preferably, the mesh portion 8 is woven from the plurality of monofilaments 14 , and the plurality of monofilaments 14 form a plurality of meshes.

[0148] Preferably, the size of the grid near the tail end 12 is smaller than the size of the grid near the head end 11 .

[0149] Preferably, the following reference Figures 9-15 The thrombus removal stent provided by an embodiment of the present invention is demonstrated.

[0150] Figure 9 This is a schematic diagram of an overall thrombectomy system provided in accordance with one embodiment of the present disclosure.

[0151] Preferably, the thrombus removal system includes a thrombus removal bracket, a conveying system and a pushing handle; the thrombus removal bracket includes a mesh bracket 1 and a spring 5, and the grid gap at one end of the mesh bracket 1 is smaller than the grid gap at the other end; a spring 5 is provided at the top of the end of the mesh bracket 1 with a smaller gap, that is, a spring 5 is provided at the tail end; it also includes two developing rings 4; one of the developing rings 4 is provided between the mesh bracket and the outer tube; the other developing ring 4 is provided between the mesh bracket and the spring 5.

[0152] Preferably, the pushing handle includes an outer shell 6 and a push handle 7; a slide is provided on the outer shell 6; the push handle 7 is provided in the slide and can slide along the slide; the outer shell 6 is connected to the other end of the outer tube, and the push handle 7 is connected to the other end of the core shaft 2, or the outer shell 6 is connected to the other end of the core shaft 2, and the push handle 7 is connected to the other end of the outer tube.

[0153] Preferably, the delivery system comprises a core shaft 2 and an outer tube for the core shaft 2 to travel. The core shaft 2 extends throughout the outer tube and the mesh stent. The top of the mesh stent 1, with the largest mesh gap, is fixed to one end of the outer tube. The end with the spring is the distal end, that is, the end away from the physician. The other end of the thrombectomy stent is the proximal end, the end closer to the physician. In the figure, the tail end 12 of the mesh stent 1 corresponds to the distal end, and the head end 11 corresponds to the proximal end.

[0154] Preferably, only the head end 11 is wound into a multifilament by first winding multiple monofilaments and then braiding them, and the tail end is directly finished without winding. In this way, the head end is wound, which is beneficial to improving the passability and compliance of the stent through tortuous blood vessels, making it easier for the stent to pass through tortuous blood vessels.

[0155] Preferably, the head end 11 is formed into a multifilament by first winding and / or welding and / or externally extruding multiple single filaments, and then braiding, and the tail end is directly terminated without winding. The winding of the head end can improve the passability and compliance of the stent through tortuous blood vessels, making it easier for the stent to pass through tortuous blood vessels.

[0156] Figure 10 、 Figure 11 as well as Figure 12 All of them are structural diagrams of the mesh bracket provided in one embodiment of this specification, and the mesh bracket 1 is Figure 9 The mesh bracket 1 in the.

[0157] Preferably, the mesh stent 1 is woven from a plurality of monofilaments, wherein at least two monofilaments are first wound into multifilaments, wherein Figure 9 It is a mesh stent 1 made of two monofilaments wound into a single wire. Figure 11 The four monofilaments are wound into multifilament.

[0158] Preferably, when four monofilaments are used for winding, two monofilaments can be first wound and / or welded and / or extruded by external force to form a multifilament, and then two multifilaments are wound again, such as Figure 12As shown. A plurality of multifilaments form a head end 11, and then a plurality of single filaments constituting the head end 11 are woven to form a mesh stent 1. After a certain length of the mesh stent 1 is formed, at least two single filaments are wound and / or welded and / or externally extruded into multifilaments to form a tail end 12. The head end 11 and the tail end 12 can be connected to the developing ring 4. This can simplify the arrangement of the mesh stent at the head end and the tail end, facilitate the start and end of weaving the stent, and make the connection of the head end and the tail end easier. In addition, the single filaments are wound first, which increases the strength of the stent while ensuring the passability of the original stent. This is conducive to improving the passability and compliance of the stent through tortuous blood vessels, making it easier for the stent to pass through tortuous blood vessels.

[0159] Figure 13 、 Figure 14 as well as Figure 15 Each of them is a schematic diagram of the process of winding a monofilament into a multifilament according to an embodiment of this specification. Figure 14 The expression may be that more than two monofilaments 14 are wound into a multifilament 13, Figure 15 The winding process may be performed two or more times. For example, four monofilaments 14 may be wound into a multifilament 13 first, and then the multifilament may be divided into two smaller multifilaments, and the two monofilaments 14 may be wound together.

[0160] Preferably, Figure 13 In the embodiment, two monofilaments 14 are wound into a multifilament 13, and three, four or more monofilaments can also be used for winding. The monofilaments in the present application are all superelastic wires or metal wires.

[0161] Preferably, Figure 13 As shown in the figure, one of the three monofilaments can be a flat wire and the other two can be round wires. If four monofilaments are wound into a multifilament, one can be a flat wire and the other three can be round wires. This thrombectomy stent woven with one flat wire and multiple round wires has a large radial force during thrombectomy and is easily embedded in the thrombus. The flat wire has a large radial support force and can also provide support to the thrombectomy stent when passing through tortuous blood vessels, reducing twisting. The "hybrid weaving process of super-elastic round wire and super-elastic flat wire" has been added to the structure of the mesh stent 1. This structural form increases the ability of the stent to fit into the thrombus while ensuring the original stent's wall adhesion and flexibility. The thrombus is not easy to fall off during the thrombectomy process, thereby improving the thrombectomy efficiency.

[0162] Preferably, the mesh portion 8 comprises a plurality of meshes woven from a plurality of monofilaments 14, wherein the gaps between the meshes adjacent to the head end 11 are larger than those adjacent to the tail end 12, such as Figure 1 、 Figure 2 、 Figure 3 、 Figure 7 、 Figure 8 shown.

[0163] Preferably, Figure 14 and Figure 15 As shown, when the multifilament 13 is woven from more than 3 single filaments 14, the diameter of the multifilament 13 in the axial direction perpendicular to the catheter is not greater than the diameter of 2 single filaments, that is, multiple single filaments 14 are woven flat in the axial direction of the catheter. This can minimize the diameter of the two ends of the mesh stent, which is more conducive to the passability of the stent.

[0164] Preferably, when the multifilament 13 is woven from a plurality of monofilaments 14, the cross section of the woven multifilament 13 can be approximately circular, such as Figure 14 As shown; or in an approximately rectangular shape, such as Figure 15 When the cross-section of the multifilament yarn 13 is approximately rectangular, the length of the multifilament yarn in the first direction is less than or equal to 2A, and the length of the multifilament yarn in the second direction is greater than or equal to 3A. A is the diameter of the single filament yarn 14 wound into the multifilament yarn 13; the first direction is perpendicular to the second direction.

[0165] Preferably, the cross section of the mesh portion 8 near the tail end 12 is smaller than the cross section of the mesh portion 8 near the head end 11 .

[0166] Preferably, the mesh portion 8 gradually converges on a side close to the tail end 12 .

[0167] Figure 16 A schematic diagram of the structure of a grid support provided in one embodiment of this specification is shown in FIG. Figure 16 As shown, in the process of weaving the monofilament 14 into the mesh portion 8, the size of the mesh of the mesh portion 8 remains basically unchanged from the head end 11 to the middle section of the mesh portion 8, but the size of the mesh of the mesh portion 8 gradually decreases from the middle section of the mesh portion 8 to the portion near the tail end 12, that is, gradually converges, and the outer surface of the mesh portion 8 gradually converges radially, so that the size of the mesh of the mesh portion 8 near the tail end 12 is reduced, that is, the mesh of the mesh at the tail end 12 close to the mesh stent is smaller and denser than that in the middle or head end 11, which can prevent or reduce the escape of thrombus from the mesh near the tail end.

[0168] It should be noted that all preferred embodiments in this specification can be combined with each other, and this specification does not limit this.

[0169] It should be noted that the monofilament 14 and / or multifilament 13 at one or both ends of the thrombus removal stent is coiled around the axis of the thrombus removal stent (eg Figure 20 shown).

[0170] It should be noted that the monofilaments 14 and / or multifilaments 13 at one or both ends of the thrombus removal stent are oriented in a substantially parallel and non-crossing manner (e.g. Figure 1-3 shown).

[0171] The above are thrombectomy stents provided in one or more embodiments of this specification. Based on the same idea, this specification also provides the use of the thrombectomy stent provided in any of the above embodiments in the treatment of deep vein thrombosis, pulmonary embolism or ischemic stroke.

[0172] The above is a thrombectomy stent provided in one or more embodiments of this specification. Based on the same idea, this specification also provides a method for manufacturing a mesh stent 1 of a thrombectomy stent.

[0173] Figure 21 This is a flow chart of a method for manufacturing a mesh stent 1 of a thrombectomy stent provided in one embodiment of the present specification, as shown in FIG. Figure 21 As shown, the method includes the following steps:

[0174] S900: Winding one end of a plurality of monofilaments into a plurality of multifilaments by winding one end of at least two monofilaments into a multifilament.

[0175] S902: The plurality of multifilaments are gathered or wound into the head end of the mesh stent 1 .

[0176] S904: braiding the plurality of monofilaments.

[0177] S906: Gather or weave the other ends of the multiple monofilaments into the tail end of the mesh stent 1 .

[0178] It should be noted that all actions of acquiring signals, information or data in this application are carried out in compliance with the relevant data protection laws and policies of the country where they are located and with the authorization given by the owner of the corresponding device.

[0179] It should also be noted that the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, commodity, or apparatus that includes a series of elements includes not only those elements but also other elements not explicitly listed, or includes elements inherent to such process, method, commodity, or apparatus. In the absence of further limitations, an element defined by the phrase "comprises a ..." does not exclude the presence of other identical elements in the process, method, commodity, or apparatus that includes the element.

[0180] The various embodiments in this specification are described in a progressive manner. Similar portions between the various embodiments can be referenced to each other. Each embodiment focuses on the differences from the other embodiments. In particular, the embodiment of the method for manufacturing the mesh stent of the thrombectomy stent is generally similar to the embodiment of the thrombectomy stent, so the description is relatively simple. For relevant portions, refer to the description of the embodiment of the thrombectomy stent.

[0181] The foregoing is merely an embodiment of the present invention and is not intended to limit the present invention. Various modifications and variations are possible for those skilled in the art. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention are intended to be included within the scope of the claims of this application.

Claims

1. A thrombus removal stent, characterized in that: The thrombus removal stent comprises a mesh stent; The mesh stent comprises a plurality of monofilaments woven together; One end of at least two monofilaments is wound into a multifilament, and a plurality of multifilaments are gathered together or wound into the first end of the mesh stent; The other ends of the plurality of monofilaments are gathered together or wound to form the second end of the mesh stent.

2. The thrombus removal stent according to claim 1, characterized in that: The other ends of the at least two monofilaments can be wound into multifilaments, and a plurality of multifilaments can be gathered together or wound into the second end of the mesh stent.

3. The thrombus removal stent according to claim 1, characterized in that: The multifilament is formed by winding one end of two, three or four monofilaments.

4. The thrombus removal stent according to claim 1, characterized in that: The monofilaments include flat filaments and round filaments; Among the at least two monofilaments constituting the multifilament, there is at least one flat yarn.

5. The thrombus removal stent according to claim 4, characterized in that: For any multifilament, in the at least two monofilaments constituting the multifilament, the number of round filaments is greater than or equal to the number of flat filaments.

6. A method for manufacturing a mesh stent for a thrombectomy stent, characterized in that: include: Winding one end of a plurality of monofilaments into a plurality of multifilaments by winding one end of at least two monofilaments into a multifilament; Gathering or winding the plurality of multifilaments into the head end of the mesh stent; braiding the plurality of monofilaments; The other ends of the plurality of monofilaments are gathered or braided into the second end of the mesh stent.

7. A thrombus removal stent, characterized in that: The thrombus removal stent comprises a mesh stent; The mesh support comprises a first end, a second end, and a mesh portion between the first end and the second end; The mesh stent is composed of a plurality of monofilaments woven together; The first end comprises at least one multifilament; the multifilament is formed by winding and / or welding and / or extruding the same end of at least two monofilaments; The first end has a first end fixing portion; The monofilaments and / or multifilaments constituting the first end are fixed to the first end fixing portion.

8. The thrombus removal stent according to claim 7, characterized in that: The first end of the mesh support is the head end; The second end of the mesh support is the tail end.

9. The thrombus removal stent according to claim 8, characterized in that: The head end of the mesh stent is formed by gathering and / or winding and / or welding and / or extruding at least one monofilament and at least one multifilament; The tail end is formed by directly gathering and / or winding and / or welding and / or extruding one end of multiple monofilaments, or the tail end is formed by gathering and / or winding and / or welding and / or extruding multiple multifilaments, or the tail end is formed by gathering and / or winding and / or welding and / or extruding at least one monofilament and at least one multifilament.

10. The thrombus removal stent according to claim 8 or 9, characterized in that: The number of monofilaments constituting the mesh stent is 12; One end of three monofilaments is gathered and / or wound and / or welded and / or externally extruded into a multifilament; One end of the three monofilaments and the three multifilaments are gathered or wound together to form the head end of the mesh stent.

11. The thrombus removal stent according to claim 8 or 9, characterized in that: The number of monofilaments constituting the mesh stent is 12; One end of two monofilaments is gathered and / or wound and / or welded and / or externally extruded into a multifilament; One end of the four monofilaments and the four multifilaments are gathered or wound together to form the head end of the mesh stent.

12. The thrombus removal stent according to claim 8 or 9, characterized in that: The mesh portion includes a plurality of meshes woven from a plurality of monofilaments; The spaces between the grids near the head end are larger than those between the grids near the tail end.

13. Use of the thrombectomy stent according to any one of claims 1-5, 7-12 in the treatment of deep vein thrombosis, pulmonary embolism or ischemic stroke.

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