CN115040197A

CN115040197A - Thrombus capture system

Info

Publication number: CN115040197A
Application number: CN202210720908.4A
Authority: CN
Inventors: 蔡诗洲; 周睿
Original assignee: Shijie Medical Technology Guangzhou Co ltd
Current assignee: Shijie Medical Technology Guangzhou Co ltd
Priority date: 2022-06-23
Filing date: 2022-06-23
Publication date: 2022-09-13

Abstract

The thrombus capture system comprises a pushing member and at least two thrombus removal members, wherein the thrombus removal members are arranged on the pushing member, the thrombus removal members are in a grid-shaped self-expansion structure, the near ends of the thrombus removal members are converged at the joint of the pushing member and the pushing member, the thrombus removal members at least comprise a first thrombus removal member positioned at the more near end and at least one second thrombus removal member arranged along the far end direction, the far end of the grid-shaped structure of the first thrombus removal member is opened to form an opening, and at least one section of the second thrombus removal member adjacent to the first thrombus removal member extends into the opening to be nested in the first thrombus removal member. The adjacent two thrombectomy components of this application thrombus capture system are nested bilayer structure mutually, form the structure of inside and outside double-deck mesh, can be at two positions embedding thrombi of inlayer and skin, can produce two impetus to the thrombus, keep the balance of the moment that the thrombus receives, produce bigger thrombus and grab power, can snatch better and fix the thrombus, prevent that the thrombus from escaping.

Description

Thrombus capture system

[ technical field ] A method for producing a semiconductor device

The present application relates to the field of medical devices, and more particularly, to a thrombus capture system.

[ background of the invention ]

At present, intracranial diseases are usually treated by adopting a vascular intervention mode, wherein mechanical thrombus removal can quickly recanalize occluded blood vessels, improve the recanalization rate of the blood vessels, reduce the dose of thrombolytic drugs, reduce the incidence rate of symptomatic cerebral hemorrhage and prolong the treatment time window, so that more time can be won for reversible ischemic brain tissues, and the prognosis of patients is obviously improved.

When a doctor carries out radiography or treatment on a patient, a thrombus taking support and a pushing core wire are usually pushed into a blood vessel together through a micro catheter, the conventional thrombus taking support is generally embedded into the thrombus through a single-layer mesh outside, so that the thrombus taking mode is hung on the thrombus, and after the thrombus is grabbed by a thrombus taking component, the grabbed thrombus needs to be dragged to a blood vessel area with a larger diameter so as to be taken out of a large-caliber catheter. And the thrombus is hung to the current support of getting to tie up all only circular individual layer meshwork, and there is not the cradling piece in the circular meshwork, can't produce axial direct impetus to the thrombus when snatching the thrombus.

Inside in order to enable the cradling piece embedding thrombus, current thrombectomy support needs the support to keep certain radial force, relies on this radial force of outside expansion to imbed the cradling piece inside the thrombus to snatch the thrombus. Therefore in the design of support, all there are a lot of naked cradling pieces with the support face of blood vessel laminating, when the thrombus was grabbed to the support and the thrombus was dragged towards the near-end, the support surface inevitably can contact with the vascular wall, especially when crooked vascular position, naked support surface metal pole can produce great scraping damage to the blood vessel.

In practical clinical application, the thrombus taking stent is generally fixed on the pushing core wire, and then the stent and the pushing core wire are pushed into the microcatheter together. Through the microcatheter, the push rod pushes the stent to the cerebral blood vessel part needing thrombus removal, and in the pushing process, particularly when the stent passes through the bent part of the blood vessel, the pushing resistance can be increased rapidly because the pushing force of the push rod is difficult to be transmitted to the far end of the stent. Meanwhile, the transmission of the pushing force on the general embolectomy support depends on the support rods at the near end to drive the support rods at the far end, and because each support rod is in different shapes and angles, the efficiency of transmitting the force to the support rods nearby can be attenuated to a certain extent, so that the integral pushing resistance of the support can be increased.

Therefore, there is a need to design a thrombus extraction device which is more flexible in operation, meets the requirements of different operations, can be flexibly regulated and controlled, has strong thrombus capture capability, can improve the operation efficiency, relieve the pain of patients, reduce complications, improve the procedure efficiency and improve the operation effect.

[ summary of the invention ]

The application aims to provide a thrombus capture system which is more flexible to operate and has a good operation effect.

In order to realize the purpose of the application, the following technical scheme is provided:

the present application provides a thrombus capture system comprising a pusher member and at least two embolectomy members, the at least two embolectomy members disposed on the pusher member, the embolectomy members are of a mesh-like self-expanding structure, the proximal end of each embolectomy member converges at the junction with the pusher member, the at least two embolectomy members comprise at least a first embolectomy member located more proximally, at least a second embolectomy member disposed in the distal direction, the mesh-like structure distal end of the first embolectomy member is flared to form an opening, and at least one section of the second embolectomy member adjacent to the first embolectomy member extends into the opening such that it nests in the first embolectomy member.

At least one section of farther end thrombectomy component in this application thrombus capture system stretches into more near-end thrombectomy component for two adjacent thrombectomy components are the bilayer structure of nested mutually, form the structure of inside and outside double-deck mesh, can imbed the thrombus at inlayer and two outer positions, can produce two impetus to the thrombus, keep the balance of the moment that the thrombus received, produce bigger thrombus grabbing power, can snatch and fix the thrombus better, prevent that the thrombus from escaping.

In some embodiments, the first embolectomy member comprises a first diameter section, the second embolectomy member comprises a second diameter section and a third diameter section, the first diameter section and the third diameter section each having a diameter greater than the second diameter section, and the second diameter section of the second embolectomy member extends at least partially into the first diameter section of the first embolectomy member.

In some embodiments, it includes a plurality of the second embolectomy members arranged sequentially, with the second diameter section of the more distal second embolectomy member extending at least partially into the third diameter section of the adjacent more proximal second embolectomy member.

In some embodiments, the embolectomy member further comprises a third embolectomy member disposed on the pushing member more proximally of the distal end, the third embolectomy member comprising a fourth diameter section and a fifth diameter section, the fourth diameter section being smaller than the third diameter section of the second embolectomy member, and the fourth diameter section of the third embolectomy member extending at least partially into the third diameter section of the adjacent more proximal second embolectomy member.

When the smaller diameter section of the thrombus taking component is transited to the larger diameter section, the middle part of the thrombus taking component is uniformly transited and connected by the support rods of the radially expanded latticed frame, and when the support rods of the radial expansion move in the axial direction, the thrombus can be directly pushed, so that the thrombus can be better grabbed and the thrombus can be prevented from escaping. The mesh size of great diameter section is great relatively, and the large granule thrombus of being convenient for falls into latticed structure smoothly, and the mesh size of less diameter section is less relatively, has great radial force and is convenient for can imbed the thrombus, and big or small mesh size cooperatees, can catch the thrombus smoothly to avoid droing of thrombus to escape.

In some embodiments, the third embolectomy member is further provided with a furling section extending from the distal end of the fifth diameter section, and the distal end of the furling section is connected with the pushing member.

The furling section enables the third embolectomy member lattice structure to form a distal closed configuration.

And the far end side of the third bolt taking component is also provided with an end net, the near end side of the end net is connected with the third bolt component, and the far end side of the end net is closed in a furled mode.

The end net is of a net structure woven by adopting wire materials, the woven wire materials can adopt nickel titanium, stainless steel wires or other polymer wire materials, the near end side of the wire materials is connected with the support rod of the third bolt taking component through a sleeve, the far end sides of the wire materials are gathered into bundles and fixed by the sleeve or a developing spring.

In some embodiments, a resilient member is disposed between the distal end of the third embolectomy member and the distal end of the pushing member, and/or the proximal end of the first embolectomy member is also provided with an opposing resilient member.

In some embodiments, the first diameter section of the first embolectomy member, the second diameter section of the second embolectomy member, and the fourth diameter section of the third embolectomy member are in the range of 0.5-3mm in diameter, and the third diameter section of the second embolectomy member and the fifth diameter section of the third embolectomy member are in the range of 2-6mm in diameter.

In some embodiments, at least one of the at least two peg members is rotatably connected with the pushing member. The proximal end of the embolectomy member is fixed on the pushing member or connected to the pushing member through a connecting piece, and the connecting piece can rotate and/or slide back and forth relative to the pushing member. Specifically, the connecting piece is a furling ring, the furling ring is sleeved on the pushing member, the support rods of the latticed structure of the bolt taking member are furled and connected to the furling ring, and the furling ring can rotate relative to the pushing member or can rotate relative to the pushing member and can also slide back and forth relative to the pushing member.

In some embodiments, the second stop on the distal side comprises at least two fixed blocks spaced around the circumference of the pusher member, with a spacing slot between adjacent fixed blocks that can accommodate the width of at least one stent rod. In clinical use of the thrombus capture system, the embolectomy member is compressed in a microcatheter for delivery into a blood vessel, the embolectomy member is in a compressed configuration, the lattice-like structure of the embolectomy member extending outward from the furling ring is radially adjacent to the pushing member, and the stent struts of the lattice-like member are receivable in the spacer grooves, so that the compressed configuration of the embolectomy member is more compact, the cross-sectional area of the compressed embolectomy member is smaller, and the pushing resistance is also reduced.

In some embodiments, the push member comprises a push rod and a push core wire engaged, at least the second corking member being connected to the push core wire.

Compared with the prior art, the method has the following advantages:

This kind of inside and outside double-deck support net structure that this application thrombus was caught in system and was taken a bolt component and adopt, the quantity that is located the cradling piece of outer large diameter section is less than the quantity of the pole of prior art individual layer support, consequently will be less with the cradling piece of blood vessel contact, and inlayer net and outer net structure adopt smooth and sly transition, have greatly reduced the scraping damage to blood vessel. In addition, when the smaller diameter section of the thrombus taking component is transited to the larger diameter section, the middle part of the thrombus taking component is uniformly transited and connected by the support rods of the radially expanded latticed frame, and when the support rods which are radially expanded move in the axial direction, the thrombus can be directly pushed, so that the thrombus can be better grabbed and the thrombus can be prevented from escaping. The mesh size of great diameter section is great relatively, and the large granule thrombus of being convenient for falls into latticed structure smoothly, and the mesh size of less diameter section is less relatively, has great radial force and is convenient for can imbed the thrombus, and big or small mesh size cooperatees, can catch the thrombus smoothly to avoid droing of thrombus to escape.

The thrombus taking component in the thrombus capturing system has at least two, namely compared with the existing integrated thrombus taking support, the thrombus taking support for capturing thrombus is divided into a plurality of sections, the length of each thrombus taking component is relatively short, each thrombus taking component can flexibly swing relatively, when the thrombus taking support passes through a bent blood vessel part, each thrombus taking component still can keep the original shape and diameter and can be attached to the blood vessel wall, and therefore the thrombus is prevented from falling off and escaping when the thrombus passes through the bent blood vessel. In addition, the plurality of thrombus taking components are arranged, when the pushing component is pulled outwards, thrombus is generally embedded into the first thrombus taking component firstly, but even if the thrombus falls off, the thrombus is captured by the second thrombus taking component or the third thrombus taking component, so that the falling off and the escape of the thrombus are avoided.

Each thrombus taking component in the thrombus capturing system is connected to the pushing core wire, and when the thrombus taking component and the pushing core wire are pushed into the micro catheter together in practical clinical application and then pushed into a blood vessel by the micro catheter, and in the pushing process of the micro catheter, pushing force can be transmitted to each thrombus taking component by the pushing core wire, so that the transmission efficiency of the pushing force is increased, and particularly at the bending part of the blood vessel, the pushing resistance can be obviously reduced by the design.

[ description of the drawings ]

FIG. 1 is an elevation view of a thrombus capture system according to a first embodiment of the present application;

FIG. 2 is a perspective view of a thrombus capture system according to a first embodiment of the present application;

FIG. 3 is a schematic view of a thrombus capture system according to an embodiment of the present application;

FIG. 4 is a schematic view of a first embodiment of an embolectomy member of a thrombus capture system of the present application;

FIG. 5 is a schematic view of a second embodiment of a first thrombus removal member of the thrombus capture system of the present application;

FIG. 6 is a schematic view of a second embodiment of an embolectomy member of a thrombus capture system of the present application;

FIG. 7 is a schematic view of a second embodiment of a second thrombus removal member in a thrombus capture system according to the present application;

FIG. 8 is a schematic view of a third embodiment of an embolectomy member of a thrombus capture system of the present application;

FIG. 9 is an enlarged view of a portion a of FIG. 2;

FIG. 10 is a partially schematic illustration of one embodiment of a visualization member of the thrombus capture system of the present application;

FIG. 11 is a partial schematic view of a second embodiment of a visualization member of the thrombus capture system of the present application;

FIG. 12 is an elevation view of a second embodiment of a thrombus capture system according to the present application;

FIG. 13 is a schematic view of a third thrombectomy member of the second embodiment of the thrombus capture system of the present application extending forward;

FIG. 14 is a perspective view of a third thrombectomy member of the second embodiment of the thrombus capture system of the present application extending forward.

[ detailed description ] embodiments

Exemplary embodiments of the present application will be described in more detail below with reference to the accompanying drawings. While exemplary embodiments of the present application are shown in the drawings, it should be understood that the present application may be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art.

It is to be understood that the terminology used herein is for the purpose of describing particular example embodiments only, and is not intended to be limiting. As used herein, the singular forms "a", "an" and "the" may be intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms "comprises," "comprising," "including," and "having" are inclusive and therefore specify the presence of stated features, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and/or groups thereof. The method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order described or illustrated, unless specifically identified as an order of performance. It should also be understood that additional or alternative steps may be used.

Although the terms first, second, third, etc. may be used herein to describe various elements, components, regions, layers and/or sections, these elements, components, regions, layers and/or sections should not be limited by these terms. These terms may be only used to distinguish one element, component, region, layer or section from another region, layer or section. Terms such as "first," "second," and other numerical terms when used herein do not imply a sequence or order unless clearly indicated by the context. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the example embodiments.

For convenience of description, spatially relative terms, such as "inner", "outer", "lower", "below", "upper", "above", and the like, may be used herein to describe one element or feature's relationship to another element or feature as illustrated in the figures. Such spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if the device in the figures is turned over, elements described as "below" or "beneath" other elements or features would then be oriented "above" or "over" the other elements or features. Thus, the example term "below … …" can include both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.

In the field of interventional medical devices, an end of a medical device implanted in a human or animal body closer to an operator is generally referred to as a "proximal end", an end farther from the operator is referred to as a "distal end", and the "proximal end" and the "distal end" of any component of the medical device are defined according to the principle. "axial" is to be understood in this application to mean the direction in which the embolectomy device is advanced, a direction perpendicular to "axial" is defined as "radial", and "longitudinal" is to be understood as the direction in which the physical dimension of the embolectomy device is longest.

Referring to fig. 1 and 2, the present application provides a thrombus capture system comprising a pushing member and at least two thrombus removal members, in this embodiment, three thrombus removal members are provided, namely, a first thrombus removal member 100 located at a more proximal end, at least one second thrombus removal member 200 located in sequence along a distal direction, and a third thrombus removal member 300 located at a most distal end, wherein the thrombus removal members are in a grid-like self-expanding structure and have a compressed configuration and an expanded configuration formed by self-expansion from the compressed configuration, the proximal end of each thrombus removal member converges at a connection with the pushing member, and in the expanded configuration, the thrombus removal members extend and expand from the connection to the distal direction to form a grid-like frame structure.

The thrombus removal members are arranged on the pushing member, generally on the pushing core wire 410, the proximal end of each thrombus removal member is converged at the joint of the pushing member and the proximal end of each thrombus removal member, the joint is provided with a connecting piece 401, the support rods of the meshes of the thrombus removal members extend from the connecting pieces to the distal direction to form a mesh-type frame, and each mesh on the mesh-type frame is a thrombus inlet. In a specific embodiment, the proximal end connector of the embolectomy member can be in a sleeve structure, and the front end of the support rod of the grid-type frame is inserted into the sleeve to be fixed, and is connected to the pushing core wire 410 through the sleeve.

The lattice-like structure of the first embolectomy member 100 is flared distally to form an opening into which at least a portion of the second embolectomy member 200 adjacent to the first embolectomy member 100 extends such that it nests within the first embolectomy member 100. Specifically, the first embolectomy member 100 includes a first diameter section 110, the second embolectomy member 200 includes a second diameter section 210 and a third diameter section 220, and the third embolectomy member 100 includes a fourth diameter section 310 and a fifth diameter section 320. The first diameter section 110 and the third diameter section 220 each have a larger diameter than the second diameter section 210, and the second diameter section 210 of the second peg member 200 extends at least partially into the first diameter section 110 of the first peg member 100. The third diameter section 220 and the fifth diameter section 320 are each larger in diameter than the fourth diameter section 310, and the fourth diameter section 310 of the third embolectomy member 100 extends at least partially into the third diameter section 220 of the adjacent, more proximal, second embolectomy member 200. Accordingly, the second diameter section 210, the fourth diameter section 310 may be referred to as a small diameter section, and the first diameter section 110, the third diameter section 220, and the fifth diameter section 320 may be referred to as a large diameter section. In the assembly process of the device, the small diameter section of the thrombus removal component at the far end is placed into the large diameter section of the thrombus removal component at the near end, so that the whole thrombus removal component has an inner layer stent mesh structure and an outer layer stent mesh structure on the axial section, please refer to fig. 3, the inner layer stent mesh structure and the outer layer stent mesh structure can better fix thrombus 10, so that the thrombus is not easy to fall off, and fig. 3 is a schematic diagram of the thrombus 10 falling between the two layers of mesh structures.

In some embodiments, which include a plurality of the second embolectomy members 200 arranged in series, the second diameter section 210 of a more distal second embolectomy member 200 extends at least partially into the third diameter section 220 of an adjacent more proximal second embolectomy member 200. These second corking members 200 may be identical or may have slightly different diameters and lengths depending on the nesting configuration described above.

In general, the diameters and lengths of the second diameter section 210 and the fourth diameter section 310 may be the same or different, and the diameters and lengths of the first diameter section 110, the third diameter section 220 and the fifth diameter section 320 may be the same or different, based on the above-described nesting structure.

When the smaller diameter section of the thrombus taking component is transited to the larger diameter section, the middle of the thrombus taking component is uniformly transited and connected by the support rods of the radially expanded latticed frame, and when the support rods which are radially expanded move in the axial direction, the support rods can directly push thrombus, so that the thrombus can be better grabbed, and the thrombus can be prevented from escaping. The mesh size of great diameter section is great relatively, and the large granule thrombus of being convenient for falls into latticed structure smoothly, and the mesh size of less diameter section is less relatively, has great radial force and is convenient for can imbed the thrombus, and big or small mesh size cooperatees, can catch the thrombus smoothly to avoid droing of thrombus to escape. For example, the first embolectomy member 100 extends from the connecting element 401 and smoothly transitions to the first diameter section 110, this transition portion may also be referred to as a first transition section (not labeled), the second embolectomy member 200 and the third embolectomy member 300 also extend from the connecting element 401 and smoothly transition to the second diameter section 210 and the fourth diameter section 310, respectively, except that the second diameter section 210 and the fourth diameter section 310 are relatively small in diameter, the transition portion is not obvious relative to the first transition section, and the second diameter section 210 and the fourth diameter section 310 also extend and smoothly transition to the third diameter section 220 and the fifth diameter section 320, respectively.

In this embodiment, the third embolectomy member 100 is further provided with a furled section 330 extending distally from the fifth diameter section 320, which furled section forms a distal closed configuration of the lattice structure of the third embolectomy member 100. The distal end of the furling section is connected with the pushing member, and a distal spring 402 is arranged at the connection position. The tail end of the pushing component is provided with a guide head 403, two ends of the far-end spring 402 are respectively abutted against the guide head and a far-end connecting piece of the third bolt taking component 100, and the tail end of the guide head 403 is an arc surface.

In a specific embodiment, the embolectomy member is machined from a nickel titanium material. The nickel-titanium material is characterized by superelasticity, the thrombus taking component is in a contracted state when being placed in the microcatheter and is delivered to a blood vessel part through the microcatheter, and after the microcatheter is removed, the latticed framework structure of the thrombus taking component can expand to restore the shape under the natural form.

As shown in fig. 1 and 2, the proximal end of the first embolectomy member 100 is provided with a proximal spring 404, one end of the proximal spring 404 abuts against the proximal connector of the first embolectomy member 100, and the other end abuts against a stop element arranged on the pushing member, or is fixedly connected with the pushing member, in this embodiment, the diameter of the pushing member is increased to generate a fixing effect on the proximal spring 404 sleeved thereon. The distal spring 402 and the proximal spring 404 are springs made of a developing material, typically 20-50cm in length, that fit over the pusher member. The latticed self-expansion structure of the plug taking component can also be provided with a developing part, and the developing part can be a developing spring, a developing ring, a developing sheet press rivet or a surrounding developing wire.

In this embodiment, the diameter of the pushing member is larger at the proximal end and smaller at the distal end, and the diameter change may be a gradual transition change along the axial direction, and the design of the diameter change of the pushing member facilitates better flexibility at the distal end and better rigidity at the proximal end for pushing. In particular, the push member includes a more proximal push rod 420 and a connected push core wire 410 that may be secured together in abutting relation at a first embolectomy member connector location. The core wire 410 and the rod 420 may be the same wire or different wires may be connected in a butt joint manner. Different wires have different rigidity and flexibility, for example, one end close to an operator needs a wire with high rigidity, such as stainless steel, so that the force is convenient to transfer; in the place where the thrombectomy member is installed, since the thrombectomy member needs to be made of a material which is tough, easily bendable, and not bent to reach the end of the intracranial bent vessel, the hardness of the push core wire 410 is generally lower than that of the push rod 420, and the push core wire 410 is made of a nickel-titanium wire in many cases. The wire connection mode includes direct butt welding and also includes the mode of inserting two sections of wires into the same casing for adhering or welding. The diameter of the push core wire 410 is in the range of 0.05-0.4, and the proper diameter range can provide better push force and flexibility and can smoothly pass through a microcatheter to send the instrument to the corresponding position of the blood vessel.

In a specific embodiment, the first diameter section 110 of the first embolectomy member 100, the second diameter section 210 of the second embolectomy member 200, and the fourth diameter section 310 of the third embolectomy member 100 have diameters in the range of 0.5-3mm, and the third diameter section 220 of the second embolectomy member 200 and the fifth diameter section 320 of the third embolectomy member 100 have diameters in the range of 2-6 mm.

The parts of the peg-removing members which are nested in each other have a larger clearance, for example, the diameter of the small-diameter section can be in the range of 0.5-1mm, and the diameter of the large-diameter section can be in the range of 2-3 mm; for another example, when the diameter of the small diameter section is in the direct range of 1-2mm, the diameter of the large diameter section is in the range of 3-6mm, and the foregoing is merely exemplary, and the value can be selected according to the specific situation, and is not limited to the above example. A larger gap exists between each thrombus taking component, when a large white thrombus with higher hardness and toughness is encountered, the gap can conveniently enable the large thrombus to fall into the grid structure of the thrombus taking component, and the large thrombus is hung and fixed by the grid, so that the thrombus is easily captured and is not easy to escape.

The thrombus of the human body is more common that the blood vessel stent at the tail end of an internal carotid artery, or a middle cerebral artery, the internal carotid artery is approximately in a range of 4-6mm, the middle cerebral artery is approximately in a range of 2-3mm, and the diameter of the larger diameter sections of the first diameter section 110, the third diameter section 220 and the fourth diameter section 310 in the thrombus taking component is selected to be optimal in a range of about 10% larger than the diameter of the blood vessel, so that the thrombus can be cut and attached to the blood vessel with proper supporting force. The diameter of the second diameter section 210 and the fourth diameter section 310 in the embolectomy component is preferably 1-2.5mm, for example, the diameter can be 1.5 mm; the lengths of the smaller diameter sections of the second diameter section 210 and the fourth diameter section 310 are within the range of 10-30 mm. These diameter section stent meshes have a relatively appropriate mesh size and are spaced from the large diameter section at an appropriate distance to facilitate the catching of thrombus with the large diameter section.

The maximum width range of the thrombus capture system in the radial direction in the completely unfolded state of the thrombus removal member is 2mm to 6mm in diameter, and the preferred maximum width in the radial direction is 2mm to 3mm, 3mm to 4mm, and 5mm to 6mm (according to the sizes of the parts with different vessel diameters), so that the diameter ranges of the third diameter section 220 of the second thrombus removal member 200 and the fifth diameter section 320 of the third thrombus removal member 100 are between 2mm to 6mm, or 2.5mm to 6mm, or the proper diameter ranges are selected according to the sizes of the parts with different vessel diameters; the length of the larger diameter sections of the third diameter section 220 and the fifth diameter section 320 is within the range of 5-25 mm.

The thickness of the pipe or the sheet of the support rod of the latticed frame of the bolt taking component is 0.05 mm-0.5 mm. The material thickness of the tubular or sheet stent struts of the lattice-like framework cannot be made too small in consideration of the requirement of the radial force of the embolectomy member (which is the outward expansion force of the embolectomy member lattice-like framework expanding from the compressed small-diameter state to the large-diameter state), and cannot be made too large in consideration of the cutting and grasping effect of the embolectomy member on the thrombus. The width range of the support rod is 0.04 mm-0.2 mm. In addition, the size range of the stent rod is also considered to be adapted to the inner diameter of the microcatheter housing the embolectomy member.

Referring to fig. 4 and 5, which are schematic views of the first embolectomy member 100 according to an embodiment, the first embolectomy member 100 of the embodiment of fig. 4 includes a first extension section 101, a second extension section 102, and a third extension section 103 connected to each other in a grid-like structure, and the stent struts of the second extension section 102 extend from the stent strut branches of the third extension section 103; the support rods of the third extending section 103 extend from the support rods of the second extending section 102 in a branched manner and are in a rhombic lattice shape, and the connection of the support rods of the second extending section 102 and the support rods of the third extending section 103 also forms a quadrangular lattice shape. The two sides in the figure are correspondingly combined with each other. Unlike the embodiment of fig. 4, in which the first tampon member 100 of the embodiment of fig. 5 includes a first elongated section 104, a second elongated section 106, and a third elongated section, which extends from the first elongated section 104 after the first transition branch 105 extends from the stent rod branch and then extends from the second elongated section 106, the third elongated section includes an upper elongated branch 109, a lower elongated branch 107, and a second transition branch 108 connected therebetween, the stent rod branch of the embodiment of the lattice structure is more. During the thrombus removal procedure, the portion of the thrombus capture system is typically placed at the site of the thrombus so that it can cut into the embedded thrombus to immobilize the thrombus, thus requiring a large radial force on the portion and the structural design of the proximal end using a closed loop configuration. Larger rod widths and dimensioning, preferably, the rod width ranges between 0.04 and 0.2 mm.

Referring to fig. 6 and 7 in combination, which are schematic expanded views of an embodiment of the second embolectomy member 200, the latticed structure of the second embolectomy member 200 of the embodiment in fig. 6 includes a fourth extending section 201, a fifth extending section 202, a sixth extending section 203 and a seventh extending section 204 which are connected, a stent rod of the fifth extending section 202 extends from a stent rod branch of the fourth extending section 201, and the fifth extending section 202 is in a multi-layer continuous connected rhombic lattice shape; the support rods of the sixth extension section 203 extend from the diamond-shaped end support rod branches of the fifth extension section 202, and the ends of the adjacent support rods are connected; the seventh extension section 204 branches from the end of the support rod of the sixth extension section 203 and is in the shape of a plurality of layers of rhombic grids which are continuously connected; the connection of the struts of the sixth extension 203 to the struts of the seventh extension 204 also forms a quadrilateral lattice. The two sides in the figure are correspondingly combined with each other. The second embolectomy member 200 lattice structure of the embodiment of fig. 7 is similar to that of the embodiment of fig. 6, except that the number of layers of the plurality of layers of continuously connected diamond-shaped lattice of the fifth elongated section 202 is relatively small but the number of transverse lattices is large, and the seventh elongated section 204 is provided with a third transition branch 205. This is an intermediate component of the thrombus capture system, having two portions, a large diameter portion and a small diameter portion. The two diameter sections are connected by a radially expanded stent rod. The connecting rods with radial expansion are smoothly connected with the large and small diameter sections, so that the damage to the vessel wall is reduced when the stent is withdrawn in the vessel. The large-diameter section has larger meshes, so that large-particle thrombus can fall into the stent conveniently, and the small-diameter section has smaller mesh size but larger radial force so as to be embedded into the thrombus conveniently. Preferably the small diameter section has a diameter of between 1 and 2.5mm and a length of between 10 and 30mm and the large diameter section has a diameter in the range of between 2.5 and 6 mm. The length is between 5 and 25 mm. The number of intermediate parts may be not less than 1.

Please refer to fig. 8, which is an expanded schematic view of an embodiment of a third embolectomy member 300, wherein the latticed structure of the third embolectomy member 300 includes an eighth extension 301, a ninth extension 302, a tenth extension 303, and a furling net segment 304, which are connected, a stent rod of the ninth extension 302 extends from a stent rod branch of the eighth extension 301, and the ninth extension 302 is in a multi-layer continuous connected rhombic lattice shape; the support rods of the tenth extension section 303 extend from the diamond-shaped end support rod branches of the ninth extension section 302, and the ends of the adjacent support rods are connected; the furling net segment 304 extends from the tail end branch of the support rod of the tenth extension segment 303, is in a shape of a plurality of layers of rhombic grids which are continuously connected, gradually reduces the number of transverse rhombic grids from the second layer, and has a furling shape with a single rhombic grid at the tail end; the connection of the strut of the tenth extension 303 to the strut of the converging network section 304 also forms a quadrilateral lattice. The two sides in the figure are correspondingly combined with each other. This is the trailing end member of the thrombus capture system, which, like the intermediate member, also has a small diameter section and a large diameter section, except that the trailing stent strut branches off and then converges to form a mesh structure at the trailing end. The purpose of this structure is to be able to capture the thrombus that has fallen during the pulling of the thrombus.

Referring to fig. 9, in the present embodiment, the proximal ends of the second embolectomy member 100 and the third member 300 are connected to the pushing member through a connecting member, the connecting member is a furling ring 406, the support rods of the lattice structure of the embolectomy member are furled and connected to the furling ring 406, and the furling ring 406 is sleeved on the pushing member and can rotate and slide back and forth relative to the pushing member.

The pushing members at both sides of the proximal end and the distal end of the furling ring 406 are respectively provided with a first stop member 405 and a second stop member 407, which can respectively limit the forward and backward movement positions of the furling ring 406, and the first stop member 405 and the second stop member 407 are fixed on the pushing members, and can be respectively realized by adopting a fixed ring or a discontinuous fixed block structure, or other forms such as bumps.

In this embodiment, the second stopper 407 on the distal side includes at least two fixing blocks spaced around the circumference of the pushing member, and a spacing groove 471 is formed between adjacent fixing blocks to accommodate the width of at least one rack bar. In clinical use of the thrombus capture system, the embolectomy member is compressed in a microcatheter for delivery into a blood vessel, the embolectomy member is in a compressed configuration, the lattice-like structure of the embolectomy member extending outwardly from the furling ring 406 is radially adjacent to the pushing member, and the stent struts of the lattice-like member are receivable in the spaced grooves 471, such that the compressed configuration of the embolectomy member is more compact, the cross-sectional area of the compressed embolectomy member is smaller, and the resistance to pushing is also reduced.

And a third stop 408 which extends from the furling ring 406 to the direction of the second stop 407 and is matched with the fixed block of the second stop 407 is arranged between the support rods of the latticed structure of the bolt taking members extending outwards from the furling ring 406, and the second stop 407 and the third stop 408 are in interference fit so as to control the distance between the furling ring 406 and the second stop 407 and avoid that the support rods are propped open due to the second stop 407 approaching the furling ring 406 too much when the bolt taking members are in a compressed configuration.

In the process of catching thrombus by the thrombus taking component, because the relative position of the thrombus and the support rod of the latticed structure is uncertain, when the thrombus cannot enter the inner space of the thrombus taking component due to the blocking of the support rod, resistance is correspondingly generated, the scheme of folding the ring 406 in a rotatable mode allows the support rod to rotate under the action of the resistance, so that the thrombus can fall into the latticed structure more conveniently, and the thrombus is captured and taken out more easily.

The first stop member 405 and the second stop member 407 may be fixed on the push core wire 410 by bonding or welding, in some embodiments, the first stop member 405 and the second stop member 407 may be close to two ends of the furling ring 406, so that the furling ring 406 may only rotate, in another embodiment, the first stop member 405 and the second stop member 407 may also have a certain distance from two ends of the furling ring 406, so that the furling ring 406 may rotate and simultaneously move back and forth, which facilitates the bolt-taking member to have a certain movement space in the axial direction, and facilitates the automatic adjustment of the position of the bolt-taking member in the axial direction according to the position of the thrombus.

Referring to fig. 10 and 11, in some embodiments, the developing element is disposed at the end of the support rod of the plug member, and may be implemented in various ways, for example, in fig. 10, a small rod is extended from the front end of the support rod, and then the developing spring 409 is wound around the extended small rod, and the developing spring may be replaced by a developing ring. As shown in fig. 11, the front end of the holder bar is also partially protruded and opened with a groove or a through hole, and the developing block 410 is accommodated therein.

Referring to fig. 12 to 14, in the present embodiment, the first embolectomy member 101 and the second embolectomy member 201 are the same as the above, and there may be various embodiments, and here, the third embolectomy member 301 of the present embodiment is further described, the distal end of the third embolectomy member 301 is different from the above embodiments in that the end of the grid-shaped structure is connected to the end net 340, the proximal end side of the end net 340 is connected to the third embolectomy member 301, and the distal end side of the end net is closed. The end net 340 is a net structure woven by adopting wires, the diameter of the wires is smaller, a structure with very small meshes can be woven, and the structure with the smaller meshes is convenient for the device to capture finer escaping thrombus and prevent the thrombus from entering intracranial small blood vessels to cause infarction. The braided wire material can be nickel titanium, stainless steel wire or other polymer wire material, the near-end side of the wire material is connected with the support rod of the third embolectomy component 100 through a sleeve, specifically, a steel sleeve is sleeved on the tail end of the support rod, then one end of the braided wire is converged into a bundle to be connected into the steel sleeve, and the bundle is fixed through welding or bonding. The distal end sides of the wires are gathered into a bundle and fixed by a sleeve or a spring, the spring can be made of developing materials, the position of the device can be observed conveniently in an operation, and meanwhile, the spring structure has flexibility, so that blood vessels are prevented from being damaged.

The above description is only a preferred embodiment of the present application, and the protection scope of the present application is not limited thereto, and any equivalent changes based on the technical solutions of the present application are included in the protection scope of the present application.

Claims

1. A thrombus capture system comprising a pusher member and at least two thrombus removal members disposed on the pusher member, the thrombus removal members being in a lattice-like self-expanding configuration with a proximal end of each member converging at a junction with the pusher member, the at least two thrombus removal members comprising at least a first thrombus removal member located more proximally, at least a second thrombus removal member disposed in a distal direction, the lattice-like configuration of the first thrombus removal member being distally open to form an opening, at least a portion of the second thrombus removal member adjacent the first thrombus removal member extending into the opening such that it nests in the first thrombus removal member.

2. The thrombus capture system of claim 1, wherein the first embolectomy member comprises a first diameter section and the second embolectomy member comprises a second diameter section and a third diameter section, each of the first diameter section and the third diameter section having a larger diameter than the second diameter section, the second diameter section of the second embolectomy member extending at least partially into the first diameter section of the first embolectomy member.

3. The thrombus capture system of claim 2, comprising a plurality of the second embolectomy members arranged in series, wherein the second diameter section of a more distal second embolectomy member extends at least partially into the third diameter section of an adjacent more proximal second embolectomy member.

4. The thrombus capture system of claim 2, wherein the embolectomy member further comprises a third embolectomy member disposed more distally on the pushing member, the third embolectomy member comprising a fourth diameter section and a fifth diameter section, the fourth diameter section being smaller than the third diameter section of the second embolectomy member, and the fourth diameter section of the third embolectomy member extending at least partially into the third diameter section of the adjacent more proximal second embolectomy member.

5. The thrombus capture system of claim 4, wherein the third thrombus removal member further comprises a furled section extending distally from the fifth diameter section, the furled section distal end being connected to the pusher member.

6. The thrombus capture system of claim 5, wherein a resilient member is disposed between the distal end of the third embolectomy member and the distal end of the pushing member, and/or a resilient member is disposed against the proximal end of the first embolectomy member.

7. The thrombus capture system of claim 4, wherein the distal side of the third thrombus member further comprises an end mesh, the proximal side of the end mesh being connected to the third thrombus member, the end mesh being closed by the distal side.

8. The thrombus capture system of claim 4, wherein the first diameter section of the first embolectomy member, the second diameter section of the second embolectomy member, and the fourth diameter section of the third embolectomy member have diameters ranging between 0.5-3mm, and the third diameter section of the second embolectomy member and the fifth diameter section of the third embolectomy member have diameters ranging between 2-6 mm.

9. The thrombus capture system of any one of claims 1-8, wherein at least one of the at least two thrombus removal members is rotatably coupled to the pusher member.

10. The thrombus capture system of any one of claims 1-8, wherein the proximal end of the embolectomy member is secured to the pushing member or is connected to the pushing member by a connector that can rotate and/or slide back and forth relative to the pushing member.