Thrombus extraction stent and thrombus removal system

Abstract

The invention provides a thrombus extraction support and a thrombus removal system, and relates to the technical field of medical instruments.The thrombus extraction support comprises a support and a mesh basket which are supported on the far-end section of a long and thin operating rod, the support and the mesh basket both have an expansion state relative to the initial state, the support comprises a support body, and the support body has the form of being expanded into a cage-shaped structure; the frame body is used for cutting or scraping thrombus; the mesh basket comprises ribs and pores, and the mesh basket is used for intercepting or capturing free thrombus; the radial supporting force of the support is larger than that of the mesh basket, or the radial supporting capacity of the support is larger than that of the mesh basket. The thrombus extraction stent in the scheme combines two functions of cutting and capturing, and thrombus of different types and states can be treated in one operation.

Description

Technical Field

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

[0002] Peripheral arterial disease (PAD) refers to arterial diseases outside the heart or brain. PAD mainly refers to the formation of atherosclerotic plaques in peripheral blood vessels such as the common iliac artery, femoral artery, radial artery, and brachial artery, and the vascular stenosis is greater than 50%. AMI (acute mesenteric ischemia) is called "intestinal stroke". It has an insidious onset and develops rapidly. The symptoms and signs are often inconsistent. It is very easy to misdiagnose or miss the diagnosis, and the mortality rate is 20-50%.

[0003] Peripheral venous diseases are divided into two categories: chronic venous insufficiency and venous thromboembolism. Chronic venous insufficiency mainly includes venous valve insufficiency, varicose veins, and sequelae of venous thrombosis. Venous thromboembolism mainly includes deep vein thrombosis (DVT) and pulmonary thromboembolism (PE), among which PE is mainly caused by DVT. Simple thrombolysis and anticoagulation and surgical treatment are the main methods for treating acute deep vein thrombosis of the lower extremities. Due to the poor effect of simple thrombolysis and anticoagulation and high recurrence rate, it has been replaced by surgical treatment. Thrombectomy such as catheter-directed contact thrombolysis (CDT), surgical incision and thrombectomy, percutaneous mechanical thrombectomy (PMT) and other comprehensive procedures have been developed. The commonly used thrombectomy catheter in China is mainly Angio Jet.

[0004] In the prior art, for example, Medtronic's CN201380069871 and CN201310471114 describe a self-expanding device with multiple grids at the proximal and distal ends, the distal end of which is an opening, which is now a universal treatment structure for neurointerventional stents; CN202110845847 describes a thrombectomy device with adjustable diameter and length, including a controller, a delivery guide wire and a plurality of cage stent units, the controller having a gripping portion and a control button disposed in the gripping portion, the cage units can be uniformly controlled so that one thrombectomy device can meet the needs of blood vessels of various diameters; CN202310700501 describes a double-layer thrombectomy stent, including an outer stent, the proximal end of the outer stent is connected to a push tube, and the inner side of the distal end of the outer stent is connected to an inner layer of a braided microfilter, the structure can effectively prevent thrombus escape; CN202020677733 describes a thrombectomy assembly and a thrombus removal device for removing thrombus from iliac vein embolism. The thrombus removal assembly includes: a thrombus isolation filter that can be radially elastically expanded and coaxially arranged, and a thrombus capture basket; the thrombus isolation filter and the thrombus capture basket are fixedly connected, and the modified structure can effectively remove thrombi. CN202010216583 describes a filter assembly and a thrombus suction assembly for removing pulmonary embolism thrombi. The filter assembly includes: a thrombus crushing filter that can be radially elastically expanded and coaxially arranged, a first isolation filter and a second isolation filter; the thrombus crushing filter is arranged between the first isolation filter and the second isolation filter. The thrombus suction assembly includes: a thrombus suction tube, a thrombus output tube, a thrombus suction device and a connecting seat with a hollow channel, which can effectively remove large thrombus structures.

[0005] Generally speaking, the existing technologies on the market have their own advantages and disadvantages. For example, Angio Jet uses the Bernoulli method to break up and remove thrombi, Indigo uses negative pressure to extract thrombi, and FlowTriever uses a stent to remove thrombi. Each thrombectomy method has its own advantages and disadvantages. During clinical practice, surgeons may also use a combination of methods to remove thrombi.

[0006] The implementation of the present invention aims to improve the efficiency of thrombus removal while reducing vascular endothelial damage, thereby providing a new option for operators. Summary of the invention

[0007] The purpose of the present invention is to provide a method to solve the problems existing in the above-mentioned prior art and improve the efficiency and effect of thrombus removal.

[0008] To achieve the above object, the present invention provides the following solutions.

[0009] A thrombus removal stent comprises a stent and a mesh basket supported on the distal end section of a slender operating rod, wherein both the stent and the mesh basket are in an expanded state relative to an initial state, the stent comprises a frame body, the frame body has a shape expanded into a cage-like structure, and the frame body is used to cut or scrape thrombi; the mesh basket comprises ribs and pores, and the mesh basket is used to intercept or capture free thrombi; the radial supporting force of the stent is greater than the radial supporting force of the mesh basket, or the radial supporting capacity of the stent is greater than the radial supporting capacity of the mesh basket.

[0010] A thrombus removal stent comprises a stent and a mesh basket supported on the distal end section of a slender operating rod, the stent and the mesh basket both have an expanded state relative to an initial state, the stent comprises a frame body and a hub, the frame body has a shape expanded into a cage-like structure, the frame body comprises spokes and thrombus-cutting ribs, one end of the spoke is fixedly connected to the hub, and the other end of the spoke is fixedly connected to the thrombus-cutting ribs; the hub comprises a proximal hub close to the proximal end of the frame body, and a distal hub close to the distal end of the frame body; the number of spokes of the proximal hub is less than or equal to the number of spokes of the distal hub; the frame body is used for cutting or scraping attached thrombi on the blood vessel wall; the mesh basket comprises ribs and pores, and the mesh basket is used for intercepting or capturing free thrombi; the radial supporting force of the stent is greater than the radial supporting force of the mesh basket, or the radial supporting capacity of the stent is greater than the radial supporting capacity of the mesh basket.

[0011] A thrombus removal stent comprises a stent and a mesh basket supported on the distal end section of a slender operating rod, the stent and the mesh basket both have an expanded state relative to an initial state, the stent comprises a frame body and a hub, the frame body has a shape expanded into a cage-like structure, the frame body comprises spokes and thrombus-cutting ribs, one end of the spoke is fixed to the hub, and the other end of the spoke is fixed to the thrombus-cutting ribs; the hub comprises a proximal hub near the proximal end of the frame body, and a distal hub near the distal end of the frame body; the mesh basket comprises ribs and pores, and the mesh basket is used to intercept or capture free thrombi; the radial supporting force of the stent is greater than the radial supporting force of the mesh basket, or the radial supporting capacity of the stent is greater than the radial supporting capacity of the mesh basket; the frame body comprises a first stent pore near the proximal end of the frame body, and a second stent pore near the distal end of the frame body; the geometric dimensions of the first stent pore are greater than the geometric dimensions of the second stent pore; the mesh basket is deployed at the distal end of the stent and maintains a longitudinal gap with the distal hub of the stent.

[0012] Furthermore, when the radial compression is to 50% of the expanded state, the limiting conditions are met: the radial support force of the stent is 0.005 to 5 N / mm, and the radial support force of the basket is 0.0005 to 2 N / mm.

[0013] Furthermore, when radially compressed to 50% of the expanded state, the following conditions are satisfied: 0.01 N / mm≤ radial support force of the stent≤0.2 N / mm, 0.001 N / mm≤ radial support force of the basket≤0.08 N / mm.

[0014] Furthermore, compared to stents, the flexible and easily deformable basket mesh ribs can increase friction and winding strength by deforming when they come into contact with viscous thrombus.

[0015] Furthermore, the basket also includes a proximal basket hub disposed at the proximal end of the basket, and basket spokes; one end of the basket spoke is fixedly connected to the proximal basket hub, and the other end of the basket spoke is fixedly connected to the rib; at least 3 or more basket spokes are circumferentially spaced apart on the proximal basket hub.

[0016] Furthermore, in the expanded state, the basket has a basket-shaped cage-like spatial form extending away from the proximal basket hub toward the distal end of the thrombus removal stent; the outer contour of the basket-shaped cage-like spatial form has a waveform formed in the longitudinal direction; with the extension line of the proximal basket hub as the baseline, the waveform includes a peak away from the baseline and a trough close to the baseline; compared with the non-loaded thrombus state, the trough can be further approached to the baseline due to the action of the thrombus.

[0017] Furthermore, the basket also includes a distal basket hub disposed at the distal end of the basket; the pore geometric dimensions close to the proximal basket hub are greater than the pore geometric dimensions close to the distal basket hub.

[0018] Furthermore, the basket also includes a distal basket hub deployed at the distal end of the basket; in the expanded state, the basket has a basket-shaped cage-like spatial form extending away from the proximal basket hub toward the distal end of the thrombus removal bracket; the basket is provided with a filter membrane, and a plurality of filter holes are distributed on the filter membrane.

[0019] Further, the proximal hub is coaxially fixed on the joystick, and the distal hub can slide in a controllable manner along the longitudinal direction; or, the distal hub is coaxially fixed on the joystick, and the proximal hub can slide in a controllable manner along the longitudinal direction.

[0020] Furthermore, in the expanded state, the stent can form a cage-like structure with different diameters.

[0021] Furthermore, a spoke is fixedly connected to two or more embolization ribs to form a divergent unit; the divergent unit has a converging portion that converges the spokes and the embolization ribs; taking the line between the proximal hub and the distal hub as the baseline, it is defined that: in the self-expanding expansion state, the distance from the outer contour of the stent to the baseline is the self-expanding radius of the stent; the distance from some converging portions to the baseline is greater than 0.5 times the self-expanding radius of the stent.

[0022] Furthermore, the distances from some convergent portions to the baselines are less than or equal to 0.5 times of the self-expanding radius of the stent.

[0023] A thrombus removal system includes any of the above-mentioned thrombus removal stents, and also includes a suction catheter that can be connected to a negative pressure source, and a sleeve that can keep the thrombus removal stent in an initial state; the sleeve is arranged outside the thrombus removal stent, and the sleeve extends from the distal end of the thrombus removal stent to the proximal end of the operating rod; the sleeve can pass through the lumen of the suction catheter to transport the thrombus removal stent; the sliding of the distal end of the sleeve toward the proximal end of the thrombus removal stent allows the thrombus removal stent to be released into an expanded state.

[0024] Furthermore, it also includes a joystick connected to the proximal end of the joystick, and the joystick controls the expansion or longitudinal displacement of the thrombus removal stent through a pulling wire or a rod.

[0025] Furthermore, the operating handle includes a handle shell, a slider and a screw rod; the handle shell supports the screw rod, the slider and the screw rod are slidably matched, and the handle shell limits the circumferential rotation of the slider rod.

[0026] Furthermore, it also includes a mesh sheath used in conjunction with the suction catheter; and / or, a blocking balloon is deployed near the distal end of the suction catheter.

[0027] Furthermore, the joystick is a hollow tube; a plurality of through holes are arranged on the tube wall near the distal end of the joystick, and the through holes are used to apply thrombolytic drugs in the blood vessel cavity.

[0028] Beneficial effects of the present invention:

[0029] The thrombectomy stent in this solution combines the two functions of cutting and capturing, and can handle thrombi of different types and states in one operation. By setting the radial support capacity of the stent to be greater than the radial support capacity of the basket, the stent can provide stronger support in the blood vessel, ensuring that it is effectively deployed and closely attached to the blood vessel wall, so as to better perform cutting and scraping operations; the basket mainly relies on weaker support force to maintain its shape, which is convenient for capturing free thrombi, achieving efficient synergistic thrombectomy, and also making this solution applicable to a variety of vascular environments, especially those cases with complex thrombus conditions;

[0030] This solution adopts a staged design of basket-first deployment, so that the basket can capture free thrombus before the stent is deployed, thereby improving the working efficiency and safety of the entire device and effectively preventing the spread of thrombus fragments.

[0031] In this solution, a bifurcated unit is provided to disperse stress, thereby optimizing the secondary shear effect of the thrombectomy stent during the retrieval process and reducing the risk of secondary shearing of the thrombus. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0033] Figure 1 A physical diagram of the thrombus removal stent 1 provided by the embodiment of the present invention;

[0034] Figure 2This is a real picture of a simulated thrombus removal process using the thrombus removal stent 2 provided in an embodiment of the present invention;

[0035] Figure 3 for Figure 2 The longitudinal distribution diagram of thrombus in the basket after the middle basket intercepts or captures the free thrombus;

[0036] Figure 4 This is a real picture of the simulated removal of thick thrombus using the thrombus removal stent 2 provided in the embodiment of the present invention;

[0037] Figure 5 for Figure 4 The concentrated distribution of thrombi at the distal end of the stent after cutting or scraping the thick thrombi in the stent;

[0038] Figure 6 A schematic diagram of a three-dimensional structure of a thrombus removal stent 3 having a corrugated grid unit is provided for use in an embodiment of the present invention;

[0039] Figure 7 for Figure 6 Schematic diagram of the structure of the medium wave grid unit;

[0040] Figure 8 A schematic diagram of the three-dimensional structure of the thrombus removal stent 4 provided by the embodiment of the present invention;

[0041] Fig. 9 A schematic diagram of a three-dimensional structure of a thrombus removal stent 5 having a wave-shaped outer contour is provided for use in an embodiment of the present invention;

[0042] Fig.10 A schematic diagram of a three-dimensional structure of an integrated thrombus removal stent 6 is provided for use in an embodiment of the present invention;

[0043] Fig.11 A schematic diagram of a basket structure with proximal clustering is provided for utilizing an embodiment of the present invention;

[0044] Fig.12 A schematic diagram of a basket structure with a filter membrane is provided for utilizing an embodiment of the present invention;

[0045] Fig.13 A schematic diagram of a basket structure with an umbrella-shaped dense net is provided for utilizing an embodiment of the present invention;

[0046] Fig.14 A schematic diagram of node distribution of troughs in a corrugated basket structure is provided for use with an embodiment of the present invention;

[0047] Fig.15 A schematic diagram of the trough state of a corrugated basket before and after loading a thrombus is provided using an embodiment of the present invention;

[0048] Fig.16To provide a schematic diagram of a support structure in which the frame body is expanded into a cage-like shape using an embodiment of the present invention Figure 1 ;

[0049] Fig.17 To provide a schematic diagram of a support structure in which the frame body is expanded into a cage-like shape using an embodiment of the present invention Figure 2 ;

[0050] Fig.18 for Fig.16 A schematic diagram of the projection of the stent structure from the proximal hub of the stent to the distal hub;

[0051] Fig.19 A schematic diagram of the distance from the convergence portion to the baseline of the stent in some embodiments of the present invention;

[0052] Fig. 20 A schematic diagram of a thrombus removal system provided by the present invention;

[0053] Fig.21 This is a schematic diagram of the internal structure of the operating handle in the thrombus removal system;

[0054] Fig. 22 It is a schematic diagram of the cross-sectional structure of the operating handle in the thrombus removal system;

[0055] Fig.23 This is a schematic diagram of the connection between the pulling wire and the hub in the thrombus removal system;

[0056] Fig.24 A schematic diagram of a thrombus removal system capable of adjusting the diameter of a thrombus removal stent or reciprocating movement is provided for utilizing the present invention;

[0057] Fig.25 A schematic diagram of a thrombus removal system capable of applying thrombolytic drugs is provided for utilizing the present invention;

[0058] Fig.26 A schematic diagram of a thrombus removal system with an occluding balloon is provided for utilizing the present invention;

[0059] Fig. 27 A schematic diagram of a thrombus removal system with a mesh sheath is provided for utilizing the present invention;

[0060] In the figure: 1-thrombus removal bracket; 2-thrombus removal bracket; 3-thrombus removal bracket; 4-thrombus removal bracket; 5-thrombus removal bracket; 6-thrombus removal bracket; 101-bracket; 102-bracket; 103-bracket; 201-net basket; 202-net basket; 203-net basket; 204-net basket; 205-net basket; 300-joystick; 310-through hole; 330-flexible distal end of joystick; 400-sleeve; 500-suction catheter; 110-frame; 111-hub; 1111-proximal hub; 1112-distal hub; 112-spokes; 1121-proximal spokes of bracket; 1122-distal spokes of the stent; 113-cutting ribs; 114-divided unit; 1141-converging portion; 11411-first converging portion; 11412-second converging portion; 1151-first stent pore; 1152-second stent pore; 210-basket body; 211-basket hub; 2111-proximal basket hub; 2112-distal basket hub; 212-basket spokes; 2121-proximal basket spokes; 2122-distal basket spokes; 213-ribs; 214-pores; 240-waveform; 241-peak; 242-trough; 2401 - first wave crest; 2402- first wave valley; 2403- second wave crest; 2404- second wave valley; 2405- third wave crest; 2406- second wave valley; 2501- proximal basket hub pore; 2502- distal basket hub pore; 260- umbrella-shaped dense mesh; 600- baseline; 270- filter membrane; 2701- filter pore; 340- operating handle; 341- handle shell; 342- slider; 343- screw; 344- suction hole; 345- injection hole; 346- pulling wire; 347- rotation limiting rail; 700- mesh sheath; 510- blocking balloon; 8 00-development mark; 900-thrombus; 910-viscous thrombus; 2011-bundled distal end; 2021-non-bundled distal end; 2022-bundled; 2023-outward-expanding trumpet; 810-first waveform member; 820-second waveform member; 830-third waveform member; 840-waveform grid unit; 25-node unit; 251-first node; 252-second node; 253-third node; 920-non-loaded thrombus state; 930-loaded thrombus state; R1-stent self-expansion radius; R2 / R3-distance from the convergence part 1141 to the baseline. DETAILED DESCRIPTION

[0061] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0062] The terms "cage-like" and "cage-like structure" in the present invention refer to a three-dimensional frame structure composed of multiple rods or wires, which is similar in appearance to a cage structure (also refers to a spatial frame composed of a series of interconnected rods or wires, forming a closed or semi-closed geometric shape), with good stability and the ability to withstand radial or axial pressure. The cage-like structure has spatial stability (i.e., through multi-directional support and cross-connection, it provides excellent spatial stiffness and anti-deformation ability) and scalability (i.e., the size and shape can be adjusted as needed to adapt to different application scenarios).

[0063] In the present invention, the term "geometric dimension" refers to the specific measurement of the size and shape of an object in space. Geometric dimension includes length, width, height, radius, angle, etc.

[0064] The value or range of the term "radial support force" in the present invention is measured according to the ASTM F3067-14 standard published by the American Society for Testing and Materials (ASTM); ASTM F3067-14 published by the American Society for Testing and Materials (ASTM) provides guidance for developing in vitro test methods for measuring the radial strength or collapse pressure of balloon-expandable vascular stents and the chronic outward force of self-expanding blood vessels. The standard is applicable to balloon-expandable and self-expanding stents with tubular geometries, and it covers stents and stent grafts.

[0065] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0066] Embodiment 1

[0067] like Figures 1 to 13 As shown, a thrombus removal stent (1, 2, 3, 4, 5, 6) includes a stent (101, 102, 103, 104) and a basket (201, 202, 203, 204, 205, 206, 207, 208, 209) supported on the distal end of a slender operating rod 300, wherein the stent and the basket have an expanded state relative to an initial state ( Figures 1 to 13 The stent or basket shown is in an expanded state), the stent includes a frame body 110, and the frame body 110 has a shape that is expanded into a cage-like structure (such as Figure 16 to Figure 18As shown in the figure, the frame 110 is used to cut or scrape the thrombus (or the attached thrombus on the blood vessel wall); the basket includes ribs 213 and pores 214, and the basket is used to intercept or capture free thrombus; the radial support force of the stent is greater than the radial support force of the basket, or the radial support capacity of the stent is greater than the radial support capacity of the basket. Basket ribs 213: constitute the basic frame of the basket, forming a capture space. Basket pores 214: distributed between the ribs 213, allowing blood to pass but intercepting free thrombus. The frame 110 of the stent is designed to be able to cut or scrape the thrombus attached to the blood vessel wall, helping to loosen and remove these difficult-to-capture thrombi. The main function of the basket is to intercept or capture free thrombi that fall off the blood vessel wall to prevent them from further flowing to other parts and causing complications. The radial support force of the stent is greater than the radial support force (or support capacity) of the basket, which means that the stent can provide stronger support in the blood vessel, ensuring that it is effectively deployed and close to the blood vessel wall, so as to better perform cutting and scraping operations; while the basket mainly relies on weaker support to maintain its shape, which is convenient for capturing free thrombi. The thrombus removal stent of the present invention has high efficiency (combining the two functions of cutting and capturing, and can handle thrombi of different types and states in one operation), safety (through a staged design, the risk of damage to the blood vessel wall is reduced, and the spread of thrombus fragments is effectively prevented) and adaptability (suitable for a variety of vascular environments, especially those cases with complex thrombosis). Radial support force / radial support performance refers to the mechanical support force that the stent / basket can provide in the radial direction (i.e., the direction perpendicular to its axis), which reflects the ability of the stent / basket to maintain its openness / expansion when squeezed by the blood vessel wall or thrombus after expansion; the mesh structure, thickness, shape, etc. of the stent / basket will affect its support effect; in this application, the ASTM F3067-14 (ASTM F3067-14 (2021) Standard Guide for Radial Loading of Balloon-Expandable and Self-Expanding Vascular Stents) standard is used to test the radial support force values ​​of the stent and basket respectively. The larger the radial support force value, the macroscopic phenomenon manifested is that the stent / basket is relatively hard (not easy to compress) after expansion and deployment. The thrombectomy stent of this application is usually harder than the basket (relatively not easy to compress and deform), and the basket is softer than the stent (relatively easy to compress and deform).

[0068] The cage-like support structure can also be designed as follows: a spiral woven cage-like structure, in which the ribs are woven into a basket in a spiral shape to form a spring-like structure; a diamond woven cage-like structure, in which the ribs are woven in a diamond grid to form evenly distributed pores, and each intersection is fixed by welding or other means to ensure structural stability; a conical expansion cage-like structure, in which the support is conical as a whole, and the front end gradually expands to form a progressive capture area; a multi-layer overlapping cage-like structure, in which the support is woven from multiple layers of filaments, with a certain spacing between each layer to form a multi-layer structure; an adjustable shrinkable cage-like structure, in which the support design There is an adjustable contraction mechanism that can adjust its shape as needed during the deployment and retrieval process. The contraction mechanism is usually achieved through an external control device, such as a push rod or electromagnetic control system in the catheter; an adaptive expansion cage structure, the stent uses an adaptive expansion material and can automatically expand to a predetermined shape after entering the blood vessel; an umbrella-shaped deployment cage structure, the stent is designed to be umbrella-shaped, and the deployment is similar to the process of an umbrella opening. The umbrella design can be quickly deployed in a short time to cover a larger blood vessel section; a multi-segment series cage structure, which is composed of multiple small baskets or balloon-like structures connected in series to form a string of "beads". Similarly, the basket can also be designed as the aforementioned cage structure.

[0069] For the specific structural design of the stent or basket, the applicant's already published Chinese patent application entitled "A vascular thrombectomy frame" can also be used; the Chinese patent application has application number CN202410965918.3, application date 20240718, publication number CN118766546A, and publication date 20241015. All technical solutions and technical features of the vascular thrombectomy frame described in the specification of the Chinese patent application can be used as specific embodiments of the present application (i.e., specific examples and references for the specific structural design of the stent or basket) to further explain the concept of the present invention; although the specification of the present application fails to fully record the technical solutions of the vascular thrombectomy frame in the text of CN118766546A, it does not prevent / does not affect the text of CN118766546A from being a further supplementary explanation of the stent or basket structure example of the present application; if necessary, the text of CN118766546A can be used as part of the content of the specification of the present application. The original text of CN118766546A records: "A vascular thrombus removal frame, comprising a thrombus removal frame having a distal end and a proximal end, the thrombus removal frame being a mesh tube or cage-like structure having ribs; a narrowing portion formed by the thrombus removal frame being narrowed laterally is arranged between the distal end and the proximal end of the thrombus removal frame; the narrowing portion divides the thrombus removal frame into a first mesh portion and a second mesh portion for stripping or capturing thrombi, the second mesh portion being able to further strip or capture residual thrombi relative to the first mesh portion; the ribs forming the thrombus removal frame have a plurality of pairs of connected ribs forming a plurality of first node units; the ribs forming the narrowing portion have a plurality of pairs of connected ribs forming a plurality of second node units; the plurality of second node units form a three-dimensional array capable of laterally intercepting free thrombi."

[0070] like Fig.10 As shown, the embodiment of the present invention provides an integrated thrombus removal stent 6, including a stent 104 and a basket 206 supported on the distal end of a slender operating rod 300. The stent 104 and the basket 206 are designed as an integrated whole, that is, the stent 104 and the basket 206 are connected to each other, and the ribs at the distal end of the stent 104 serve as a support body for the proximal end of the basket 206; in other words, the elongated cage-shaped stent can be deployed with different radial support forces / radial support capabilities in the longitudinal direction (axial direction), so that the elongated cage-shaped stent is distributed with different soft and hard frames in the longitudinal direction, thereby realizing functional zoning. Furthermore, an umbrella-shaped dense net 260 is provided at the distal end of the thrombus removal stent 6 to increase the interception of small thrombi.

[0071] like Fig.11As shown, the embodiment of the present invention provides a basket 207 with proximal clustering; in other words, the hub of the thrombectomy stent of the present invention can be a cluster 2022 formed by directly gathering a number of spokes (clustered distal end 2011), rather than being limited to a ring. Further, the distal end of the basket 207 can be a non-clustered distal end 2021, which gradually moves away from the central axis to form an outward-expanding trumpet 2023.

[0072] like Fig.12 and Fig.13 As shown, the basket structure can also be attached with a filter membrane 270 having filter holes 2701 on the basket body 210, or an umbrella-shaped dense mesh 260.

[0073] The deployment process of the thrombectomy stent: the stent and the basket are initially in a compressed state (for example, compressed and accommodated in the sleeve 400), and are delivered to the target position by the slender joystick 300; after reaching the lesion site, (withdrawing the sleeve 400) the stent is first unfolded into a cage-like structure and begins to cut or scrape the attached thrombus on the blood vessel wall; then, the basket is unfolded to intercept or capture the free thrombus loosened by the stent.

[0074] The recovery process of the thrombus retriever stent: After the thrombus is removed, the stent and basket are recompressed and withdrawn into the body, carrying the captured thrombus out of the body.

[0075] Compared with the stent, the support force of the basket is weakened. The basket is designed to have weak radial support force, which plays a vital role in the overall function of the thrombectomy stent: 1) Maintaining shape and flexibility; the weak radial support force of the basket means that it will not exert excessive pressure on the vessel wall inside the blood vessel, which helps to reduce the risk of damage to the vessel wall, especially when the blood vessel is fragile or already damaged. The contact of the basket inside the blood vessel is gentle, reducing the stimulation and damage to the endothelial cells of the blood vessel, which is very important for preventing postoperative complications (such as inflammation or restenosis); the weaker support force allows the basket to adapt more flexibly to the complex geometry inside the blood vessel. When encountering a curved, bifurcated or other irregular structure of the blood vessel, the basket can fit naturally without excessive deformation or twisting; the weaker support force allows the basket to adapt more flexibly to the complex geometry inside the blood vessel, ensuring that it can be stably deployed in different vascular environments. 2) Capture free thrombus; the pores on the basket can adaptively expand and close in the thrombus capture environment, ensuring that the thrombus can be captured efficiently without significantly obstructing blood flow; the basket is designed to ensure that all loosened free thrombi can be captured, and its weaker supporting force will not cause the thrombus to fall off again or escape to the distal blood vessels, thereby improving the safety and success rate of the operation; 3) Easy to operate and recover; the weaker supporting force makes the basket smoother and more controllable during the expansion and contraction process; during the operation, the doctor can more easily and accurately position the basket to the target area, and smoothly retract it into the suction catheter 500 / cannula 400 after completing the thrombus removal; during the recovery process, the weaker supporting force of the basket enables it to be better compressed, thereby reducing the resistance during recovery and reducing the difficulty and risk of operation.

[0076] Embodiment 2

[0077] like Figures 1 to 9 and Fig.16 As shown, a thrombus removal stent includes a stent (101, 102, 103) and a net basket supported on the distal end of a slender operating rod 300, the stent and the net basket are both in an expanded state relative to an initial state, the stent includes a frame body 110 and a hub 111, the frame body 110 has a shape expanded into a cage-like structure, the frame body 110 includes spokes 112 and thrombus cutting ribs 113, one end of the spoke 112 is fixedly connected to the hub 111, and the other end of the spoke 112 is fixedly connected to the cutting ribs 113. The ribs 113 are fixedly connected; the hub 111 includes a proximal hub 1111 close to the proximal end of the frame 110, and a distal hub 1112 close to the distal end of the frame 110; the number of spokes of the proximal hub 1111 is less than or equal to the number of spokes of the distal hub 1112, so that the first support pore 1151 of the frame 110 is greater than or equal to the second support pore 1152, so that the frame 110 can scrape the thrombus attached to the blood vessel wall and hold the blocky thrombus clot 910 (such as Figure 5The thick thrombus 910 is intercepted by the distal spokes 1122 of the stent body 110); the stent body 110 is used to cut or scrape the attached thrombus on the blood vessel wall (such as Figure 2 , Figure 5 As shown, the thrombus-cutting ribs 113 scrape the thrombus 900 attached to the blood vessel wall); the basket includes ribs 213 and pores 214, and the basket is used to intercept or capture free thrombus (such as Figure 2 to Figure 4 As shown, the thrombus cutting ribs 113 scrape the thrombus 900 / viscous thrombus 910 attached to the blood vessel wall, and some thrombi 900 / viscous thrombi 910 escaping from the distal spokes 1122 of the stent are captured by the basket and further entangled and anchored); the radial support force of the stent is greater than the radial support force of the basket, or the radial support capacity of the stent is greater than the radial support capacity of the basket. Figure 16 to Figure 18 As shown, the frame 110 is unfolded into a cage-like structure, having a plurality of spokes 112 and a thrombus-cutting rib 113. Spokes 112 are fixedly connected to the hub at one end and to the thrombus-cutting rib 113 at the other end, playing a role in supporting and transmitting force. The thrombus-cutting rib 113 is connected to the spokes and used to cut or scrape the thrombus attached to the blood vessel wall. The hub 111 is located at the center of the stent and serves as a fixing point for the spokes to ensure the stability of the entire structure. The hub is mounted on the operating rod 300 and can be fixed or slidably connected (such as Fig.23 and Fig.24 As shown, the hub (one or all of them) slides back and forth on the joystick 300 by traction of the pull wire 346 fixed thereto). In this embodiment, the stent is designed to be an adaptively expandable double-conical cage-like structure; the spokes of the proximal hub 1111 / distal hub 1112 expand to form a cone (umbrella-shaped). Compared with the basket, the radial support force of the stent is stronger, so that the thrombus-cutting ribs 113 can be embedded in the thrombus to achieve cutting or scraping of the attached thrombus on the blood vessel wall. This high support force ensures that the stent can effectively handle hard thrombus blocks; when the stent enters the blood vessel, it first relies on its high radial support force (0.005~5N / mm) to open the narrowed or occluded blood vessel segment and restore the blood flow channel; this initial support provides the necessary space and environment for the deployment of the basket.

[0078] Embodiment 3

[0079] like Figures 1 to 9As shown, a thrombus removal stent includes a stent and a net basket (201, 202, 203, 204, 205, 206, 207, 208, 209) supported on the distal end section of a slender operating rod 300, the stent and the net basket are both in an expanded state relative to an initial state, the stent includes a frame body 110 and a hub, the frame body 110 has a shape expanded into a cage-like structure, the frame body 110 includes spokes and thrombus-cutting ribs 113, one end of the spoke is fixed to the hub, and the other end of the spoke is fixed to the thrombus-cutting rib 113; the hub includes a proximal hub 1111 close to the proximal end of the frame body 110, and a distal hub 1112 close to the distal end of the frame body 110; the net basket includes ribs and pores, and the net basket is used to intercept or capture free thrombi; the radial supporting force of the stent is greater than the radial supporting force of the net basket, or the radial supporting capacity of the stent is greater than the radial supporting capacity of the net basket; as shown in FIG. Figure 16 to Figure 18 As shown, the frame 110 includes a first support pore 1151 near the proximal end of the frame 110, and a second support pore 1152 near the distal end of the frame 110; the geometric size of the first support pore 1151 is greater than the geometric size of the second support pore 1152 (the frame 110 includes a first support pore 1151 near the proximal end of the frame 110, and the pore geometric size is greater than the second support pore 1152; the second support pore 1152 is deployed near the distal end of the frame 110); the basket is deployed at the distal end of the frame and maintains a longitudinal gap with the distal end hub 1112 of the frame (or the frame and the basket are arranged in sequence and at intervals on the joystick 300). The stent and the basket in the thrombectomy stent achieve efficient synergistic thrombectomy through their unique structural design, radial support force difference and functional complementarity; in particular, the design of the basket's priority deployment allows it to capture free thrombi before the stent is deployed, thereby improving the working efficiency and safety of the entire device; the stent provides strong mechanical support and cutting ability, while the basket gently captures free thrombi with its flexibility and deformation ability; this synergistic mechanism not only improves the efficiency of thrombectomy, but also minimizes damage to blood vessels and the risk of secondary detachment. The stent has a large radial support force, which can achieve good cutting of subacute and chronic thrombi.

[0080] like Figure 1 As shown, in some embodiments, the outer diameters of the support and the basket are at least partially the same or substantially the same. In some embodiments, the support and the basket are independently and spaced apart and arranged in series on the joystick 300.

[0081] When radial compression reaches 50% of the expanded state, the limiting conditions are met: the radial support force of the stent is 0.005-5N / mm, and the radial support force of the basket is 0.0005-2N / mm. This design ensures the functional complementarity of the stent and the basket. The stent provides sufficient support to cut or scrape attached thrombi, while the basket relies on weaker support to gently capture free thrombi. The two work together to improve the safety and effectiveness of the overall surgery. For patients with acute ischemic stroke, the stent can effectively cut or scrape thrombi in the main arteries of the brain, while the basket intercepts the detached thrombus fragments at the distal position to prevent them from entering smaller blood vessels and causing secondary infarction. In peripheral arterial disease (PAD) or peripheral venous disease, the stent can handle larger and stubborn thrombi, while the basket is responsible for capturing loose thrombus fragments, ensuring the treatment effect while reducing postoperative complications. Through the design of a multi-grid stent (or different grids), such as the thrombectomy stent structure design in which the stent and the basket are connected in series in Examples 1 to 3, subacute and chronic thrombi that are difficult to remove during conventional surgery can be removed. At the same time, the removed thrombi can be captured multiple times to prevent thrombus escape and reduce endothelial damage. The multi-grid structure enhances the cornering performance of the device and improves overall passability.

[0082] Furthermore, when radially compressed to 50% of the expanded state, the following conditions are met: 0.01N / mm≤ radial support force of the stent≤0.2N / mm, 0.001N / mm≤ radial support force of the basket≤0.08N / mm. Radial support force of the stent: relatively high (0.01N / mm to 0.2N / mm), which can provide sufficient support force to cut or scrape attached thrombi; the higher support force enables the thrombus-cutting ribs 113 to be embedded in the thrombus to achieve effective cutting or scraping. Radial support force of the basket: relatively low (0.001N / mm to 0.08N / mm), which gently captures free thrombi and avoids excessive pressure on the blood vessel wall; the weaker support force allows the basket to deform more flexibly and adapt to different thrombus states.

[0083] like Figure 4As shown, compared with the stent, the flexible and easily deformable mesh basket ribs can increase friction and entanglement strength by deforming when they come into contact with viscous thrombi. The weaker radial support of the mesh basket does mean that its ribs are more easily deformed, and this characteristic has a positive effect on capturing and entangling viscous thrombi. The weaker radial support of the mesh basket increases the chance of entanglement with thrombi: 1) Rib deformation and entanglement with thrombi. The weaker radial support makes the ribs of the mesh basket more flexible and able to adapt to changes in blood flow more flexibly; when encountering larger or irregularly shaped thrombi, the flexible ribs can better wrap and entangle the thrombi, increase the contact area, and thus improve the entanglement effect; the captured thrombi will gradually gather in the mesh basket to form a larger mass. Due to the flexibility of the mesh basket, it can deform slightly to accommodate more thrombi without causing blockage or rupture. 2) It is helpful to cope with the challenge of viscous thrombus; viscous thrombus is usually composed of red blood cells, fibrin and other components, with high viscosity and elasticity, and is not easy to be simply filtered or cut. For this type of thrombus, the traditional rigid structure may not be able to effectively capture it, and may even cause the thrombus to rupture or escape; the soft and deformable basket ribs can increase friction and winding strength by slightly deforming when they come into contact with viscous thrombus, and the pores between the basket ribs can also be adaptively adjusted to a certain extent according to the size and shape of the thrombus, ensuring that even very viscous thrombus can be effectively captured and fixed.

[0084] The basket also includes a proximal basket hub 2111 disposed at the proximal end of the basket, and basket spokes 212; one end of the basket spoke 212 is fixedly connected to the proximal basket hub 2111, and the other end of the basket spoke is fixedly connected to the rib; at least 3 or more basket spokes are circumferentially spaced apart at the proximal basket hub 2111.

[0085] like Fig.14 and Fig.15As shown, in the expanded state, the basket has a basket-type cage-like spatial form extending away from the proximal basket hub 2111 toward the distal end of the thrombus removal bracket; the outer contour of the basket-type cage-like spatial form has a waveform 240 formed in the longitudinal direction; with the extension line of the proximal basket hub 2111 as the baseline 600, the waveform 240 includes a peak 241 (2401, 2403, 2405) away from the baseline 600, and a trough 242 (2402, 2404, 2406) close to the baseline 600; compared with the non-thrombus-loaded state 920, the trough of the thrombus-loaded state 930 can be further close to the baseline due to the action of the thrombus. Unlike the trough (which is moved closer to the baseline due to the action of the thrombus), the basket body 210 (or ribs) at the crest has the ability to resist the radial contraction deformation force / tendency caused by the thrombus; in other words, the radial support force of the basket crest can be made greater than the radial support force of the basket trough by adjusting the geometric dimensions of the ribs (the trough ribs are softer than the crest ribs). With this design, the basket-shaped cage-like spatial form can adapt to the morphology of the blood vessels in the expanded state and increase the capture area. The crests and troughs in the outer contour of the waveform can be flexibly deformed according to the action of the thrombus, and can be closer to the baseline 600, thereby enhancing the capture effect. Fig.14 As shown, the trough 242 of the thrombus-loaded state 930 has a deformation close to the baseline 600, and the ribs at the lowest point in the trough 242 may abut against each other or stagger against each other; the abutment of the ribs can provide necessary support for the basket body 210 at the crest 241; the staggering of the ribs can make the basket body 210 at the adjacent crest 241 shrink and deform adaptively, and at the same time, increase the cross-sectional interception density at the trough 242. Considering that a single performance often cannot meet the comprehensive performance requirements of thrombus removal; further optimization, such as Fig.14 As shown, the node units 25 of the trough in the corrugated basket structure have a non-uniform distribution in the longitudinal direction; specifically, the node units 25 include a first node 251 and a second node 252, the first node 251 is evenly distributed at the bottom of the trough, and the second node 252 is evenly distributed on both sides of the bottom of the trough; such an arrangement can increase the friction and entanglement force of the basket on the thrombus, thereby increasing the comprehensive performance of the basket.

[0086] The basket also includes a distal basket hub 2112 deployed at the distal end of the basket; the pore geometry near the proximal basket hub 2111 is larger than the pore geometry near the distal basket hub 2112, so that the basket can more effectively capture free thrombus.

[0087] The basket also includes a distal basket hub 2112 deployed at the distal end of the basket; in the expanded state, the basket has a basket-shaped cage-like spatial form extending away from the proximal basket hub 2111 toward the distal end of the thrombectomy bracket; the basket is provided with a filter membrane 270, and a plurality of filter holes 2701 are distributed on the filter membrane.

[0088] like Fig.23and Fig.24 As shown, the proximal hub 1111 is coaxially fixed to the joystick 300, and the distal hub 1112 can slide controllably in the longitudinal direction through the traction of the pulling wire 346 fixed thereto; or, the distal hub 1112 is coaxially fixed to the joystick 300, and the proximal hub 1111 can slide controllably in the longitudinal direction, or both hubs of the stent can be set to slide on the joystick 300. In this embodiment, the stent is designed as a double-conical cage structure with adaptive expansion; the spokes of the proximal hub 1111 / distal hub 1112 are expanded to form a cone; either end hub of the stent is fixed to the joystick 300, and the other end hub is sleeved on the joystick 300 in a longitudinally slidable manner; the slidable hub is provided with a pulling wire or a push-pull rod, so that the stent can achieve controllable expansion (such as Fig.23 As shown, the pull wire 346 pulls the distal hub 1112 to slide in the direction of the arrow close to the proximal hub 1111, thereby forcing the frame 110 to further expand radially); by manipulating the longitudinal displacement of the pull wire or the push-pull rod, the diameter of the stent can be adjusted or the reciprocating movement (such as Fig.24 The stent is shown in Figure 3, and the relevant changes are achieved through the joystick 300 or the traction wire, and the diameter of different blood vessels is adapted. In the expanded state, the stent can form a cage-like structure with different diameters. By adjusting the diameter of the stent or reciprocating movement, a mechanical thrombectomy operation that is difficult to remove subacute and chronic thrombi through interventional surgery is achieved.

[0089] During the process of retrieving the thrombus removal stent into the sleeve 400, there is a risk that the spokes will produce a secondary shearing and fragmenting effect on the thrombus; this phenomenon may lead to the formation and escape of small thrombi, thus affecting the safety and effectiveness of the thrombectomy. Spoke contraction movement: When the operating handle controls the thrombus removal stent to retract into the sleeve 400 through the pulling wire or rod, the stent will gradually contract. At this time, the spokes and the thrombus-cutting ribs 113 will undergo relative displacement, causing friction or compression with the captured thrombus. Secondary shear effect: 1) Mechanical stress. The spokes and the thrombus-cutting ribs 113 will exert additional mechanical stress on the thrombus during the contraction process, which may cause the thrombus to further rupture or fragment. 2) Thrombus characteristics. The thrombus itself is a loose and fragile tissue that is easily broken when subjected to external forces. In particular, thrombi that have been partially cut or scraped are more susceptible to secondary shearing and fragmentation. Risk of small thrombus escape: 1) It is not easy to capture. Small thrombi are small in size and light in weight, so they can easily escape the capture range of the basket with the blood flow and enter the distal blood vessels, increasing the risk of embolism; 2) Reduced safety. The presence of small thrombi not only increases the possibility of postoperative complications, but may also require additional treatment measures, thereby prolonging hospitalization time and increasing the burden on patients. When considering how to reduce the secondary shearing and fragmentation of thrombi during the retrieval process by adjusting the design of the thrombectomy stent, increasing the length of the spokes or increasing the initial gap between the spokes are two potential design improvement directions. Increasing the length of the spokes: 1) Prolonging the contact path: Increasing the length of the spokes can make the spokes contact the thrombus more slowly during the stent contraction process, thereby reducing the sudden impact force on the thrombus; 2) Reducing local stress concentration: Longer spokes can disperse the mechanical stress applied to the thrombus to a larger area, reducing the possibility of local stress concentration, and thus reducing the risk of secondary shearing; 3) Improving flexibility: Longer spokes may have better flexibility and deformation ability, can better adapt to the shape of the thrombus, and wrap the thrombus more gently during the contraction process. However, increasing the length of the spokes may also bring some challenges: increased operational complexity; longer spokes may make the operation of the stent more complicated, especially when passing through narrow blood vessels, more resistance and obstruction may be encountered. Increasing the initial gap between the spokes: 1) Reduce direct contact. Increasing the initial gap between the spokes means that during the contraction of the stent, there will be more space between the spokes, reducing the possibility of adjacent spokes squeezing the thrombus; 2) Reduce friction. When the gap between the spokes is larger, the friction force on the thrombus during the wrapping process is relatively small, reducing the risk of secondary shear fragmentation. However, this method also has limitations: reduced structural stability. Too large a gap between the spokes may weaken the overall structural stability of the stent, especially when encountering strong blood flow impact, which can easily cause the stent to deform or fail; the capture effect is weakened. Although a larger gap helps to reduce shear, if the gap is too large, it may cause the thrombus to escape from between the spokes and cannot be effectively captured. For example Fig.19As shown, the optimization scheme can be: one spoke is fixedly connected with two or more embolization ribs 113 to form a divergent unit 114; the divergent unit 114 has a convergent portion 1141 that converges the spokes and the embolization ribs 113; the line between the proximal hub 1111 and the distal hub 1112 is taken as the baseline 600, and it is defined that: in the self-expanding state, the distance from the outer contour of the stent to the baseline is the stent self-expanding radius R1; the distance R2 from some convergent portions 1141 to the baseline is greater than 0.5 times the stent self-expanding radius; and, or, the distance R3 from some convergent portions 1141 to the baseline is less than or equal to 0.5 times the stent self-expanding radius. The spokes are fixedly connected with the embolization ribs 113 to form the divergent unit 114, which can disperse stress: since the spokes are connected with multiple embolization ribs 113, the mechanical stress can be dispersed at multiple points, avoiding local stress concentration, thereby reducing the risk of secondary shearing of thrombus. The design features of the convergence part 1141 are as follows: 1) Reduce direct contact: a larger distance (>0.5 times the self-expansion radius) means that the spokes and the thrombus-cutting ribs 113 have less direct contact with the thrombus during the contraction process, reducing the squeezing and friction of the thrombus; 2) Optimize the wrapping path: a smaller distance (≤0.5 times the self-expansion radius) allows the spokes and the thrombus-cutting ribs 113 to wrap the thrombus more tightly, ensuring that the thrombus will not escape easily. Furthermore, the uneven distribution of distances (the distance from the convergence part 1141 to the baseline is unevenly distributed, some are greater than 0.5 times the self-expansion radius of the stent, and some are less than or equal to 0.5 times) can effectively optimize the secondary shear effect generated by the thrombectomy stent during the recovery process; this design not only enhances the stability of the stent structure, but also reduces the risk of secondary shearing of the thrombus through reasonable stress dispersion and gradual contraction. Gradual contraction: The uneven design of the convergence part 1141 makes the stent present a gradual change in shape during the contraction process, rather than a sudden and drastic contraction; this gradual contraction helps to smoothly wrap the thrombus and bring it into the sleeve 400, reducing secondary damage to the thrombus. Improve capture efficiency: The design of the convergence part 1141 with different distances can cover a wider range of thrombi, improve capture efficiency, and maintain gentle treatment of thrombi. Figure 6 and Figure 7As shown, the secondary shearing of the thrombus by the spokes can also be suppressed / reduced by adding a corrugated mesh unit 840 at the distal end of the stent / basket. The corrugated mesh unit 840 is usually connected by a pair of corrugated members (e.g., 810-820, 820-830) to form a closed gourd-shaped opening; the gourd-shaped opening includes a first opening 8401 and a second opening 8402 that are connected; as an example, a 3-shaped corrugated member (composed of an outwardly convex arc 8404, an inwardly concave arc 8405, and an outwardly convex arc 8406, connected in sequence) can be preferably used to form the corrugated mesh unit 840. When the thrombus removal stent is gradually withdrawn into the lumen of the sleeve 400 or the suction catheter 500, the corrugated components on both sides of the corrugated grid unit 840 are gradually compressed and moved closer together until the inwardly concave arcs 8405 partially contact each other to resist the compression effect, so as to maintain the second opening 8402 formed by the outwardly convex arcs 8404 and prevent the thrombus stuck in the intersection 8403 of the ribs from being sheared.

[0090] Embodiment 4

[0091] like Figure 20 to Figure 23 As shown, a thrombus removal system includes a thrombus removal stent (1, 2, 3, 4, 5, 6), and also includes a suction catheter 500 that can be connected to a negative pressure source, and a sleeve 400 that can keep the thrombus removal stent in an initial state; the sleeve 400 is sleeved outside the thrombus removal stent, and the sleeve 400 extends from the distal end of the thrombus removal stent to the proximal end of the operating rod 300; the sleeve 400 can pass through the cavity of the suction catheter 500 to transport the thrombus removal stent; the sliding of the distal end of the sleeve 400 toward the proximal end of the thrombus removal stent allows the thrombus removal stent to be released into an expanded state.

[0092] The thrombus removal system further includes an operating handle 340 connected to the proximal end of the operating rod 300 , and the operating handle 340 controls the expansion or longitudinal displacement of the thrombus removal stent through a pulling wire 346 or a rod.

[0093] The operating handle includes a handle shell 341, a slider 342 and a screw 343; the handle shell 341 supports the screw 343, the slider 342 slides and cooperates with the screw 343, and the handle shell limits the circumferential rotation of the slider 342 through the rotation limiting rail 347. The slider 342 pulls the hub 111 / 211 toward the proximal end of the operating rod 300 by turning the knob screw 343, thereby achieving controllable radial expansion (adjusting the diameter or reciprocating movement) of the stent or basket.

[0094] like Fig.26 and Fig. 27As shown, the thrombus removal system also includes a mesh sheath 700 used in conjunction with the suction catheter 500; and / or, a blocking balloon 510 is deployed near the distal end of the suction catheter 500. The balloon is filled during thrombus removal, so that a front-end negative pressure is formed during the thrombus removal process, which is more conducive to suction, and during the thrombolysis process, the outflow of thrombolytic drugs is effectively prevented, thereby improving the efficiency and safety of thrombolysis. During the retraction of the stent, the thrombus attached to the stent can be recovered in the mesh sheath (usually woven into a mesh by metal wire) to prevent the thrombus from escaping during the retraction of the stent.

[0095] like Fig.25 As shown, the joystick 300 is a hollow tube; a plurality of through holes 310 are arranged on the tube wall near the distal end of the joystick 300, and the through holes 310 are used to apply thrombolytic drugs in the blood vessel cavity. The through holes 310 can be arranged in the same direction or in different directions, and thrombolytic drugs or liquids such as physiological saline are injected through the cavity of the joystick 300 to further achieve thrombolysis or thrombus fragmentation.

[0096] The stent or basket may be provided with a coating, the composition of which may be a coating having a lubricating effect, such as PVP, PTFE, etc., or a coating having a thrombolytic or thrombotic inhibitory drug, such as tactile plasminogen activator (t-PA), urokinase, warfarin, heparin, etc.

[0097] The hub of the support or basket can be a bundle of multiple ribs (spokes) or a metal ring.

[0098] Thrombectomy procedure:

[0099] Initial entry and development phase:

[0100] 1) Protection by the sheath 400: The thrombectomy stent is wrapped by the sheath 400 and maintains its initial state, so as to facilitate its delivery to the lesion site.

[0101] 2) Prioritized deployment of the basket: When reaching the target position, the withdrawn sleeve 400 first releases the basket, allowing it to deploy first, adapt to the vascular morphology and prepare to capture free thrombus.

[0102] 3) The stent is subsequently deployed: After the basket is deployed, the sheath 400 is further withdrawn to release the stent, so that the stent is deployed to open the narrowed or occluded blood vessel segment and cooperate with the basket to capture more thrombi.

[0103] Thrombus capture phase:

[0104] 1) Basket capture: The basket relies on its flexibility and deformability to gently capture free thrombus and prevent it from escaping;

[0105] 2) Stent cutting or scraping: After the stent is deployed, the thrombus-cutting ribs 113 are embedded in the attached thrombus to be cut or scraped.

[0106] Recycling stage:

[0107] 1) Tightly wrapped basket: The basket tightly wraps the captured thrombus to ensure that it does not fall off again;

[0108] 2) Negative pressure suction: The suction catheter 500 is connected to a negative pressure source and the distal suction port is kept in a negative pressure state, so that the thrombus / clot captured in the thrombectomy stent is transferred to the outside of the patient's body through negative pressure suction.

[0109] The present invention uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only used to help understand the method and core ideas of the present invention. At the same time, for those skilled in the art, according to the ideas of the present invention, there will be changes in the specific implementation methods and application scopes. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A thrombus removal stent, comprising a stent and a basket supported on a distal end section of an elongated operating rod, wherein both the stent and the basket are in an expanded state relative to an initial state, and characterized in that: The stent includes a frame body, which has a shape that expands into a cage-like structure and is used to cut or scrape thrombi; the basket includes ribs and pores, and is used to intercept or capture free thrombi; the radial supporting force of the stent is greater than the radial supporting force of the basket, or the radial supporting capacity of the stent is greater than the radial supporting capacity of the basket.

2. A thrombus removal stent, comprising a stent and a basket supported on a distal end section of an elongated operating rod, wherein both the stent and the basket are in an expanded state relative to an initial state, and characterized in that: The stent includes a frame body and a hub, the frame body has a shape that expands into a cage-like structure, the frame body includes spokes and thrombus-cutting ribs, one end of the spoke is fixedly connected to the hub, and the other end of the spoke is fixedly connected to the thrombus-cutting ribs; the hub includes a proximal hub close to the proximal end of the frame body, and a distal hub close to the distal end of the frame body; the number of spokes of the proximal hub is less than or equal to the number of spokes of the distal hub; the frame body is used to cut or scrape attached thrombi on the blood vessel wall; the basket includes ribs and pores, and the basket is used to intercept or capture free thrombi; the radial supporting force of the stent is greater than the radial supporting force of the basket, or the radial supporting capacity of the stent is greater than the radial supporting capacity of the basket.

3. A thrombus removal stent, comprising a stent and a basket supported on a distal end section of an elongated operating rod, wherein both the stent and the basket are in an expanded state relative to an initial state, and characterized in that: The stent includes a frame body and a hub, the frame body has a shape that expands into a cage-like structure, the frame body includes spokes and thrombus-cutting ribs, one end of the spoke is fixedly connected to the hub, and the other end of the spoke is fixedly connected to the thrombus-cutting ribs; the hub includes a proximal hub close to the proximal end of the frame body, and a distal hub close to the distal end of the frame body; the basket includes ribs and pores, and the basket is used to intercept or capture free thrombi; the radial supporting force of the stent is greater than the radial supporting force of the basket, or the radial supporting capacity of the stent is greater than the radial supporting capacity of the basket; the frame body includes a first stent pore close to the proximal end of the frame body, and a second stent pore close to the distal end of the frame body; the geometric size of the first stent pore is greater than the geometric size of the second stent pore; the basket is deployed at the distal end of the stent and maintains a longitudinal gap with the distal hub of the stent.

4. The thrombus removal stent according to any one of claims 1 to 3, characterized in that: When radial compression reaches 50% of the expanded state, the limiting conditions are met: the radial support force of the stent is 0.005-5N / mm, and the radial support force of the basket is 0.0005-2N / mm.

5. The thrombus removal stent according to claim 4, characterized in that: When radially compressed to 50% of the expanded state, the following conditions are met: 0.01N / mm≤stent radial support force≤0.2N / mm, 0.001N / mm≤basket radial support force≤0.08N / mm.

6. The thrombus removal stent according to claim 4, characterized in that: Compared with stents, the flexible and easily deformable basket mesh ribs can increase friction and entanglement strength by deforming when they come into contact with viscous thrombus.

7. The thrombus removal stent according to any one of claims 1 to 3, characterized in that: The basket also includes a proximal basket hub disposed at the proximal end of the basket, and basket spokes; one end of the basket spoke is fixedly connected to the proximal basket hub, and the other end of the basket spoke is fixedly connected to the rib; at least 3 or more basket spokes are disposed circumferentially at intervals on the proximal basket hub.

8. The thrombus removal stent according to claim 7, characterized in that: In the expanded state, the basket has a basket-shaped cage-like space shape extending away from the proximal basket hub toward the distal end of the thrombectomy stent; the outer contour of the basket-shaped cage-like space shape has a waveform formed in the longitudinal direction; Taking the extension line of the proximal basket hub as the baseline, the waveform includes a peak far from the baseline and a trough close to the baseline; Compared with the non-thrombus-loaded state, the trough can be moved closer to the baseline due to the effect of the thrombus.

9. The thrombus removal stent according to claim 7, characterized in that: The basket also includes a distal basket hub disposed at the distal end of the basket; the pore geometry near the proximal basket hub is greater than the pore geometry near the distal basket hub.

10. The thrombus removal stent according to claim 7, characterized in that: The basket also includes a distal basket hub deployed at the distal end of the basket; in the expanded state, the basket has a basket-shaped cage-like spatial form extending away from the proximal basket hub toward the distal end of the thrombectomy bracket; the basket is provided with a filter membrane, and a plurality of filter holes are distributed on the filter membrane.

11. The thrombus removal stent according to any one of claims 2 to 3, characterized in that: The proximal hub is coaxially fixed on the operating rod, and the distal hub can slide controllably along the longitudinal direction; or, the distal hub is coaxially fixed on the operating rod, and the proximal hub can slide controllably along the longitudinal direction.

12. The thrombus removal stent according to claim 11, characterized in that: In the expanded state, the stent can form a cage-like structure with different diameters.

13. The thrombus removal stent according to any one of claims 2 to 3, characterized in that: A spoke is fixedly connected to two or more embolization ribs to form a divergent unit; the divergent unit has a converging portion that converges the spokes and the embolization ribs; the line between the proximal hub and the distal hub is used as the baseline, and it is defined that: in the self-expanding state, the distance from the outer contour of the stent to the baseline is the stent self-expanding radius; the distance from some converging portions to the baseline is greater than 0.5 times the stent self-expanding radius.

14. The thrombus removal stent according to claim 13, characterized in that: The distances from some of the convergence parts to the baseline are less than or equal to 0.5 times the self-expanding radius of the stent.

15. A thrombus removal system, characterized in that: It includes any one of claims 1 to 14, and also includes a suction catheter that can be connected to a negative pressure source, and a sleeve that can keep the thrombectomy stent in an initial state; the sleeve is arranged outside the thrombectomy stent, and the sleeve extends from the distal end of the thrombectomy stent to the proximal end of the operating rod; the sleeve can pass through the lumen of the suction catheter to transport the thrombectomy stent; the sliding of the distal end of the sleeve toward the proximal end of the thrombectomy stent allows the thrombectomy stent to be released into an expanded state.

16. The thrombus removal system according to claim 15, characterized in that: It also includes a joystick connected to the proximal end of the joystick, and the joystick controls the expansion or longitudinal displacement of the thrombectomy stent through a pulling wire or a rod.

17. The thrombus removal system according to claim 16, characterized in that: The operating handle comprises a handle shell, a slider and a screw rod; the handle shell supports the screw rod, the slider and the screw rod are slidably matched, and the handle shell limits the circumferential rotation of the slider rod.

18. The thrombus removal system according to claim 15, characterized in that: It also includes a mesh sheath used in conjunction with the suction catheter; and / or, a blocking balloon is deployed near the distal end of the suction catheter.

19. The thrombus removal system according to claim 15, characterized in that: The joystick is a hollow tube; a plurality of through holes are arranged on the tube wall near the distal end of the joystick, and the through holes are used to apply thrombolytic drugs in the blood vessel cavity.

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