CN111067592B

CN111067592B - Thrombus taking device

Info

Publication number: CN111067592B
Application number: CN201811230459.5A
Authority: CN
Inventors: 胡龙虎
Original assignee: Lifetech Scientific Shenzhen Co Ltd
Current assignee: Lifetech Scientific Shenzhen Co Ltd
Priority date: 2018-10-22
Filing date: 2018-10-22
Publication date: 2021-11-26
Anticipated expiration: 2038-10-22
Also published as: CN111067592A

Abstract

The invention discloses a thrombus removal device which comprises a filter screen and a push-pull guide wire connected with the filter screen, wherein the filter screen comprises a filter screen main body and a clamping part connected to the filter screen main body, and one end of the clamping part, which is far away from the filter screen main body, extends towards the near end and one side, which is close to a longitudinal central shaft. The invention has the beneficial effects that: because the filter screen of this application has the clamping part, this clamping part not only can the centre gripping thrombus, makes the combination between thrombus and the filter screen more firm, can increase the area of contact of filter screen and thrombus moreover, makes the whole atress of thrombus even, avoids getting the in-process that the thrombus was withdrawn, and the thrombus is because of local atress is big and is cut into the piece.

Description

Thrombus taking device

Technical Field

The invention relates to the technical field of medical instruments, in particular to a thrombus removal device for removing thrombus in blood vessels.

Background

Stroke is a common disease type in medicine, and Acute Ischemic Stroke (AIS), commonly called cerebral infarction, is a nerve tissue injury caused by ischemic necrosis of local brain tissue due to sudden obstruction of cerebral blood flow. At present, a mechanical thrombus removal method is generally adopted for treating acute ischemic stroke, the method can quickly re-introduce the occluded blood vessel and improve the re-introduction rate of the blood vessel, but the types of thrombus are usually ignored in the design of the existing mechanical thrombus removal products.

Thrombi are classified into hard thrombi (i.e., white thrombi) which have strong viscoelasticity and are difficult to compress, and soft thrombi which are fragile. When the existing mechanical thrombus taking product is used for taking hard thrombus, the hard thrombus is only compressed between the thrombus taking product and a blood vessel wall, and the hard thrombus is easy to fall off from a thrombus taking instrument in the thrombus taking and withdrawing process, so that thrombus taking failure is caused. When the existing mechanical thrombus removal product is used for removing soft thrombus, the soft thrombus is easily divided into small thrombus or thrombus fragments to cause the re-embolism of the small blood vessel at the far end.

Disclosure of Invention

The present invention has been made to solve the above-described problems of the prior art, and an object of the present invention is to provide a thrombus removal device that can effectively remove a hard thrombus and can also well remove a soft thrombus.

The technical scheme adopted by the invention for solving the technical problems is as follows:

the utility model provides a thrombectomy device, including the filter screen and with the push-and-pull seal wire that the filter screen is connected, the filter screen includes the filter screen main part, and connects clamping part in the filter screen main part, the one end of keeping away from the filter screen main part of clamping part is towards the near-end, and extend to the one side that is close to longitudinal center axle.

In the thrombus removal device, a film is arranged in the filter screen.

In the thrombus removal device, the thickness of the clamping part is 0.1 mm-3 mm.

In the thrombus removal device, the near end of the filter screen main body and/or the far end of the filter screen main body are in a conical structure, and the taper of the conical structure is 30-60 degrees.

In the thrombus removal device, the filter screen is of a structure with two closed ends; or the near end of the filter screen is an open end, and the far end of the filter screen is a closed end.

In the thrombus removal device, the opening end of the filter screen is provided with a support piece.

In the thrombus removal device, the clamping part comprises a clamping outer layer and a clamping inner layer which are connected, the filter screen main body comprises a main body outer layer and a main body inner layer, the main body outer layer is connected with the clamping outer layer, and the main body inner layer is connected with the clamping inner layer.

In the thrombus removal device, the filter screen further comprises a connecting part, and the filter screen body is connected with the push-pull guide wire through the connecting part.

In the thrombus removal device, the thrombus removal device further comprises a thrombus removal support, and the push-pull guide wire is connected with the filter screen through the thrombus removal support.

In the thrombus removal device, the thrombus removal device further comprises an expansion balloon, and the push-pull guide wire is connected with the filter screen through the expansion balloon.

In summary, the thrombus removal device of the present invention has the following beneficial effects: because the filter screen of this application has the clamping part, this clamping part not only can the centre gripping thrombus, makes the combination between thrombus and the filter screen more firm, can increase the area of contact of filter screen and thrombus moreover, makes the whole atress of thrombus even, avoids getting the in-process that the thrombus was withdrawn, and the thrombus is because of local atress is big and is cut into the piece. In the process of taking the thrombus and withdrawing, even if part thrombus fragments fall off, the filter screen main body can also recover the fallen thrombus fragments, so that the filterability and the trapping performance of the filter screen on the thrombus fragments are improved, and the thrombus fragments are prevented from entering the distal end fine powder blood vessel to cause secondary embolism. In addition, the clamping part can also dehydrate the thrombus in the process of clamping the thrombus, reduce the volume of the thrombus and conveniently take out the thrombus.

Drawings

The invention will be further described with reference to the accompanying drawings and examples, in which:

FIG. 1 is a schematic structural diagram of a thrombus removal device according to an embodiment of the present invention;

FIG. 2 is a schematic view of the thrombectomy device shown in FIG. 1, capturing thrombi;

FIG. 3 is a schematic structural view of a filter screen of the embolectomy device shown in FIG. 1;

FIG. 4 is a schematic view of the filter screen of FIG. 3 with a membrane disposed therein;

FIG. 5 is a schematic structural view of a connecting sleeve of the embolectomy device shown in FIG. 1;

FIG. 6 is a schematic structural diagram of a thrombus removal device according to a second embodiment of the present invention;

FIG. 7 is a schematic structural view of a filter screen of the embolectomy device shown in FIG. 6;

FIG. 8 is a schematic structural diagram of a thrombus removal device according to a third embodiment of the present invention;

FIG. 9 is a schematic structural diagram of a thrombus removal device according to a fourth embodiment of the present invention;

FIG. 10 is a schematic structural diagram of a thrombus removal device according to a fifth embodiment of the present invention;

FIG. 11 is a schematic view of the thrombectomy device of FIG. 10 capturing a soft thrombus;

FIG. 12 is a schematic view of the thrombectomy device of FIG. 10 capturing hard thrombi;

fig. 13 is a schematic structural view of a thrombus removal device according to a sixth embodiment of the present invention.

Detailed Description

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein, but rather should be construed as broadly as the present invention is capable of modification in various respects, all without departing from the spirit and scope of the present invention.

It will be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "left," "right," and the like as used herein are for illustrative purposes only and do not represent the only embodiments.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

In the field of interventional medicine, it is generally defined that the end of the instrument proximal to the operator is the proximal end and the end distal to the operator is the distal end.

Referring to fig. 1, one of the preferred embodiments of the present invention provides an embolectomy device 100, which comprises a filter screen 20 and a push-pull guide wire 10 connected to the filter screen 20. The filter net 20 includes a filter net main body 21, and a clamping portion 22 connected to the filter net main body 21, wherein an end of the clamping portion 22 away from the filter net main body 21 extends toward a proximal end and toward a side close to the longitudinal central axis.

The filter net 20 is formed by heat setting an elastic woven net, which may be a net pipe structure made of a plurality of woven wires. Specifically, the braided wire may be made of a superelastic shape memory alloy material, such as a nickel-titanium alloy material, so that the filter mesh 20 may be accommodated in a compressed state in a delivery sheath (not shown), and after being released from the delivery sheath, the filter mesh 20 may automatically return to a predetermined shape (the filter mesh 20 in fig. 1 is a schematic view of the predetermined shape), and has sufficient radial supporting force.

Referring to fig. 2, when capturing the thrombus 200, the filtering mesh 20 may be delivered to the distal end of the thrombus 200 through a delivery sheath (not shown), after being released from the delivery sheath, the filtering mesh 20 automatically returns to a predetermined shape, and then the push-pull guide wire 10 is withdrawn, so that the filtering mesh 20 contacts with the thrombus 200, and the push-pull guide wire 10 is continuously withdrawn, so that the filtering mesh 20 and the thrombus 200 captured by the filtering mesh 20 are pulled into the recovery sheath 300. Because filter screen 20 has clamping part 22, this clamping part 22 not only can the centre gripping thrombus 200, makes the combination between thrombus 200 and the filter screen 20 more firm, can increase the area of contact of filter screen 20 and thrombus 200 moreover, makes the whole atress of thrombus 200 even, avoids getting the in-process that the thrombus withdraws, and thrombus 200 is because of local atress is big and is cut into the piece. In the process of taking embolus and withdrawing, even if part of thrombus fragments fall off, the filter screen main body 21 can also recover the fallen thrombus fragments, so that the filterability and the trapping performance of the filter screen 20 on the thrombus fragments are improved, and the thrombus fragments are prevented from entering the distal end fine powder blood vessel to cause secondary embolism. In addition, the clamping part 22 can dehydrate the thrombus 200 in the process of clamping the thrombus 200, reduce the volume of the thrombus 200 and facilitate taking out the thrombus 200.

Furthermore, because the end of the clamping portion 22 away from the filter screen main body 21 extends towards the proximal end and towards the side close to the longitudinal central axis of the filter screen 20, that is, the tangent line of the end of the clamping portion 22 away from the filter screen main body 21 or the end of the clamping portion 22 away from the filter screen main body 21 is inclined to the longitudinal central axis of the filter screen 20, the clamping portion 22 has a force pushing towards the proximal end to the thrombus 200 during the process of withdrawing the thrombus, which is beneficial to withdrawing the thrombus 200.

Referring to fig. 3, the filtering net 20 is a structure with two closed ends, and is a two-layer woven net structure formed by heat setting an elastic woven net, and the two-layer woven net structure can perform double-layer filtering and capturing on the fallen thrombus fragments, so as to prevent the thrombus fragments from passing through the meshes of the filtering net 20 and preventing the thrombus fragments from entering the distal end fine blood vessel to cause secondary embolism. In practical preparation, the two ends of the elastic woven net can be bound and fixed by the fixing sleeves 23 respectively, and then the elastic woven net with the two fixed ends is placed into a heat setting mold to form a two-layer woven net structure with a predetermined shape by means of high-temperature treatment. The fixing sleeve 23 can be made of metal material or rare earth material with large atomic mass, such as gold, platinum, thallium, tantalum, etc., so that the fixing sleeve 23 has better developing effect under the contrast equipment such as DSA, etc., and an operator can conveniently observe the position of the filter screen 20.

Specifically, the entire filter screen main body 21 is substantially of a cone-like structure, and includes a main body outer layer 211 and a main body inner layer 212, the main body outer layer 211 is located at the far end of the filter screen main body 21, the main body inner layer 212 is located at the near end of the filter screen main body 21, and both the main body outer layer 211 and the main body inner layer 212 are of cone-like structures, so as to facilitate pushing out and recycling the filter screen 20. It can be understood that if the taper of the outer body layer 211 and the inner body layer 212 is too small, the radial supporting force of the filter screen body 21 is small, and it is difficult to support the clamping portion 22; if the taper of the outer body layer 211 and the inner body layer 212 is too large, the radial supporting force of the filter screen body 21 is too large, so that the filter screen 20 is difficult to be compressed into the delivery sheath, which is not favorable for pushing out and retracting the filter screen 20. Therefore, the taper angles of the body outer layer 211 and the body inner layer 212 are preferably 30 ° to 60 °.

The clamping part 22 is approximately circular arc-shaped as a whole, and after the clamping part 22 is released from the delivery sheath, the point of the clamping part 22 is supported on the inner wall of the blood vessel, so that the defect that the inner wall of the blood vessel is damaged too much due to the overlarge contact area between the clamping part 22 and the inner wall of the blood vessel in the process of taking and withdrawing the embolus is avoided.

The holding portion 22 includes a holding outer layer 221 and a holding inner layer 222, the holding outer layer 221 and the holding inner layer 222 are connected by a transition layer (not numbered), the holding outer layer 221 and the body outer layer 221 are connected, and the holding inner layer 222 and the body inner layer 212 are connected. Preferably, the outer clamping layer 221 is connected with the outer main body layer 221 in an arc shape, and the inner clamping layer 222 is connected with the inner main body layer 212 in an arc shape. The outer clamping layer 221 and the inner clamping layer 222 are both arc-shaped, and the radius a of the outer clamping layer 221 is not less than the radius b of the inner clamping layer 222, so that the clamping portion 22 is bent to a side close to the longitudinal center axis of the filter screen 20. It can be understood that if the radius of the clamping outer layer 221 is too large, the axial occupied space of the clamping portion 22 is large, which is not favorable for pushing out and recovering the filter screen 20; if the radius for grasping the inner layer 222 is too small, the force for grasping the thrombus by the grasping portion 22 is small, and the thrombus 200 is difficult to grasp. Preferably, the radius a of the clamping outer layer 221 is less than 8mm, and the radius b of the clamping inner layer 222 is greater than 0.5 mm. It will also be appreciated that if the thickness of the clamping portion 22 is too great, it is not conducive to compressing the clamping portion 22 into the sheath; if the thickness of the grasping portion 22 is too small, the grasping force of the grasping portion 22 is small and the thrombus 200 is difficult to grasp, so the thickness L of the grasping portion 22 is preferably 0.1mm to 3 mm.

It will be appreciated that in other embodiments, the retaining portion 22 may be a spring or rod-like structure made of a super-elastic metal alloy or polymer material with good shape memory, such as nitinol, and the retaining portion 22 has one end connected to the filter screen body and the other end extending proximally and to a side near the longitudinal central axis. Preferably, the clamping portion 22 is circular arc-shaped, and the radius of the outer layer of the clamping portion 22 is less than 8mm, and the radius of the inner layer is greater than 0.5 mm. That is, the present application does not limit the specific structure of the grasping portion 22 as long as the grasping portion 22 can grasp the thrombus. It is also understood that the present application is not limited to the specific structure of the screen body, as long as the thrombus can be filtered or captured.

Referring to fig. 4, a film 24 is disposed in the filtering net 20 for further blocking the fallen thrombus fragments, preventing the thrombus fragments from passing through the meshes of the filtering net 20, and preventing the thrombus fragments from entering the distal end fine blood vessel to cause re-embolism. The membrane 24 may be made of a biocompatible material, such as PTFE membrane, PET membrane, etc., and the membrane 24 may be secured within the filter mesh 20 by sewing or bonding.

As shown in fig. 1 and 5, the push-pull guide wire 10 is fixedly connected to the fixing sleeve 23 at the proximal end of the filter screen 20, and the operator pushes and retracts the filter screen 20 by the push-pull guide wire 10. It should be understood that the present application is not limited to the specific connection manner of the push-pull guide wire 10 and the fixing sheath 23, and the push-pull guide wire 10 may be directly connected to the fixing sheath 23 by welding, gluing or crimping, or may be connected to the fixing sheath 23 by other members. For example, in the embodiment shown in fig. 5, the push-pull guide wire 10 is fixedly connected to the fixing sleeve 23 through a connecting sleeve 30, the connecting sleeve 30 is a hollow sleeve structure, the push-pull guide wire 10 and the fixing sleeve 23 are respectively inserted into the connecting sleeve 30, and the connecting sleeve 30 can be respectively fixedly connected to the push-pull guide wire 10 and the fixing sleeve 23 through welding, gluing or crimping. Preferably, the connection sleeve 30 can be made of metal material or rare earth material with relatively large atomic mass, such as gold, platinum, thallium, tantalum, etc., so that the connection sleeve 30 has better developing effect under the contrast equipment such as DSA, etc., and is convenient for an operator to observe the position of the filter screen 20.

Referring to fig. 6, a second preferred embodiment of the present invention provides an embolectomy device 100, which is substantially the same as the embolectomy device of the first embodiment, the embolectomy device 100 includes a filter screen 20 and a push-pull guide wire 10 connected to the filter screen 20, the filter screen 20 includes a filter screen main body 21, and a clamping portion 22 connected to the filter screen main body 21, and an end of the clamping portion 22 away from the filter screen main body 21 extends toward a proximal end and a side close to a longitudinal central axis. The second embodiment is different from the first embodiment in the structure of the screen body 21.

Referring to fig. 7, the filter net 20 is a woven net structure formed by heat setting an elastic woven net, and the proximal end of the filter net 20 is an open end and the distal end is a closed end. The open end of the filter screen 20 is provided with a support 25, and the support 25 is an elastic support ring and may be made of superelastic memory alloy. The closed end of the filter screen 20 is bound and fixed by the fixing sleeve 23, and the fixing sleeve 23 can be made of metal material or rare earth material with larger atomic mass, such as gold, platinum, thallium, tantalum and the like, so that the fixing sleeve 23 has better developing effect under the contrast equipment such as DSA and the like, and an operator can conveniently observe the position of the filter screen 20. In the actual preparation, one end of the elastic knitted net can be bound and fixed by the fixing sleeve 23, a supporting piece 25 is fixed at the port of the other end of the elastic knitted net, and then the elastic knitted net is placed into a heat setting mould and is formed into a knitted net structure with a preset shape by means of high-temperature treatment.

The filter screen main body 21 comprises a main body outer layer 211, the main body outer layer 211 is of a conical structure, and the taper of the main body outer layer 211 is 30-60 degrees, so that the filter screen main body 21 is ensured to have enough radial supporting force to support the clamping part 22, and meanwhile, the filter screen 20 is conveniently pushed out and recovered.

The clamping part 22 is approximately arc-shaped, and after the clamping part 22 is released from the delivery sheath, the point of the clamping part 22 is supported on the inner wall of the blood vessel, so that the defect that the inner wall of the blood vessel is damaged too much due to the overlarge contact area between the clamping part 22 and the inner wall of the blood vessel in the process of taking and withdrawing the embolus is avoided.

The holding portion 22 includes a holding outer layer 221 and a holding inner layer 222 connected, the holding outer layer 221 is connected with the body outer layer 221, and the holding inner layer 222 is connected with the support 25. Preferably, the clamping outer layer 221 is connected with the body outer layer 221 in a circular arc. In the embodiment shown in fig. 7, the clamping inner layer 222 is directly connected to the support 25, and it will be understood that in other embodiments, the screen body 21 may further include a body inner layer, through which the clamping inner layer 222 is connected to the support 25, and which is connected to the body inner layer 212 in an arc. It will also be appreciated that in other embodiments, the open end of the filter screen 20 may also be provided without the support 25.

The outer clamping layer 221 and the inner clamping layer 222 are both arc-shaped, and the radius a of the outer clamping layer 221 is not less than the radius b of the inner clamping layer 222, so that the clamping portion 22 is bent to a side close to the longitudinal center axis of the filter screen 20. It can be understood that if the radius of the clamping outer layer 221 is too large, the axial occupied space of the clamping portion 22 is large, which is not favorable for pushing out and recovering the filter screen and the filter portion 20; if the radius for grasping the inner layer 222 is too small, the force for grasping the thrombus by the grasping portion 22 is small, and the thrombus 200 is difficult to grasp. Preferably, the radius a of the clamping outer layer 221 is less than 8mm, and the radius b of the clamping inner layer 222 is greater than 0.5 mm. It will also be appreciated that if the thickness of the clamping portion 22 is too great, it is not conducive to compressing the clamping portion 22 into the sheath; if the thickness of the grasping portion 22 is too small, the grasping force of the grasping portion 22 is small and the thrombus 200 is difficult to grasp, so the thickness L of the grasping portion 22 is preferably 0.1mm to 3 mm.

Further, the filter screen 20 further comprises a connecting portion 26 for connecting with the push-pull guide wire 10, wherein one end of the connecting portion 26 is connected with the filter screen main body 21, and the other end is connected with the push-pull guide wire 10. In the embodiment shown in fig. 7, the connecting portion 26 comprises four connecting wires, each of which is a superelastic memory alloy wire, one end of each of the four connecting wires is connected to the support 25 at the open end, and the other ends of the four connecting wires are bundled together and fixedly connected by the fixing sleeve 23, and the fixing sleeve 23 is used for fixedly connecting with the push-pull guide wire 10.

It is understood that the present application is not limited to the specific structure of the connection portion 26, as long as the filter screen 20 and the push-pull guide wire 10 can be fixedly connected. For example, the connecting portion 26 is only one connecting wire, and one end of the connecting wire is fixed to the screen body 21 and the other end is fixedly connected to the push-pull wire 10. It should be understood that the specific material of the connecting portion 26 is not limited in this embodiment, and the connecting portion 26 may also be a nylon thread, a PET thread, a PTFE thread, or other polymer material threads.

Referring to fig. 8, a third preferred embodiment of the present invention provides an embolectomy device 100, which is substantially the same as the embolectomy device of the first preferred embodiment, the embolectomy device 100 includes a filter screen 20 and a push-pull guide wire 10 connected to the filter screen 20, the filter screen 20 includes a filter screen main body 21, and a clamping portion 22 connected to the filter screen main body 21, and an end of the clamping portion 22 away from the filter screen main body 21 extends toward a proximal end and a side close to a longitudinal central axis. The filter net 20 is a structure with two closed ends, and is a two-layer woven net structure formed by heat setting an elastic woven net. The filter screen main body 21 comprises a main body outer layer 211 and a main body inner layer 212, the clamping portion 22 comprises a clamping outer layer 221 and a clamping inner layer 222 which are connected, the clamping outer layer 221 is connected with the main body outer layer 221 in an arc mode, and the clamping inner layer 222 is connected with the main body inner layer 212 in an arc mode.

The third embodiment is different from the first embodiment only in the shape of the body outer layer 211 of the strainer body 21. In the embodiment shown in fig. 8, the body outer layer 211 is a cylindrical structure. Since the main body outer layer 211 has a cylindrical structure and a large contact area with the inner wall of the blood vessel, the force of the filter net 20 acting on the inner wall of the blood vessel per unit area is small under the same release pressure, thereby reducing the pressure of the blood vessel wall.

Referring to fig. 9, a fourth preferred embodiment of the present invention provides an embolectomy device 100, which is substantially the same as the third preferred embodiment of the present invention, the embolectomy device 100 includes a filter screen 20 and a push-pull guide wire 10 connected to the filter screen 20, the filter screen 20 includes a filter screen main body 21, and a clamping portion 22 connected to the filter screen main body 21, and an end of the clamping portion 22 away from the filter screen main body 21 extends toward a proximal end and a side close to a longitudinal central axis.

The fourth embodiment differs from the third embodiment in that the proximal end of the filter mesh 20 is an open end and the distal end is a closed end. Specifically, the filter screen main body 21 is substantially a cylindrical structure, the proximal end of the filter screen main body 21 is an open end, the distal end is a closed end, the clamping portion 22 is connected to a port of the open end of the filter screen main body 21, and the push-pull guide wire 10 is connected to the distal end of the filter screen main body 21.

Referring to fig. 10, the fifth preferred embodiment of the present invention provides an embolectomy device 100, which is substantially the same as the embolectomy device of the first preferred embodiment, and comprises a push-pull guide wire 10 and a filter screen 20. The difference is that the embolectomy device 100 further comprises an embolectomy support 40, wherein the proximal end of the embolectomy support 40 is connected with the push-pull guide wire 10, and the distal end of the embolectomy support is connected with the filter screen 20.

The thrombectomy stent 40 is a substantially hollow tubular structure having a plurality of cells 41 disposed on an outer wall thereof. The grid 41 is formed by surrounding a plurality of net rods 411, and the shape of the grid 41 may be a regular shape such as a circle, a diamond, or an irregular shape, which is not limited herein.

The embolectomy stent 40 may be made of a metal alloy or a polymer material having superelasticity and good shape memory property, preferably a nickel-titanium alloy tube, a nickel-titanium alloy wire, a nickel-titanium alloy sheet, a polymer tube, a polymer sheet or a polymer wire, etc., so that the embolectomy stent 40 may be accommodated in a compressed state in a delivery sheath (not shown), and after being released from the delivery sheath, the embolectomy stent 40 may automatically return to a predetermined shape (the embolectomy stent 40 in fig. 12 is a schematic diagram of the predetermined shape) and has sufficient radial support force. In actual preparation, the thrombectomy stent 40 can be formed by weaving nickel-titanium wires or cutting and shaping nickel-titanium tubes.

Referring to fig. 11, in capturing the thrombus 200, the thrombus removal stent 40 can be delivered to the thrombus 200 through a delivery sheath (not shown) such that the filter mesh 20 is located at the distal end of the thrombus 200. After being released from the delivery sheath, the thrombus removal stent 40 and the filter screen 20 automatically return to the predetermined shape. Referring to fig. 11, if the thrombus 200 is a soft thrombus, the mesh rod 41 will gradually penetrate into the soft thrombus in the process of gradual expansion of the thrombus removal stent 40, and even if the soft thrombus is divided into small thrombus or thrombus fragments and separated from the thrombus removal stent 40, the filter mesh 20 at the distal end of the thrombus removal stent 40 can recover the fallen thrombus fragments, so as to prevent the thrombus fragments from entering the distal end fine blood vessel to cause re-embolism. Referring to fig. 12, if the thrombus 200 is a hard thrombus, although the mesh rod 41 cannot penetrate into the hard thrombus in the gradual expansion process of the thrombectomy stent 40, the thrombectomy stent 40 continuously presses the hard thrombus during the expansion process, so that the hard thrombus is dehydrated, the volume of the hard thrombus becomes smaller, the viscoelasticity of the hard thrombus after dehydration is enhanced, the friction coefficient becomes larger, and the hard thrombus is not easily detached. In the process of withdrawing the thrombus, the hard thrombus and the thrombus taking support 40 move relatively until contacting with the filter screen 20, and the filter screen 20 is provided with the clamping part 22, so that the clamping part 22 can clamp the hard thrombus, the combination between the hard thrombus and the filter screen 20 is firmer, and the clamping part 22 can further dehydrate the hard thrombus in the process of clamping the hard thrombus, so that the hard thrombus can be conveniently taken out. Therefore, the thrombus extraction device 100 can effectively capture hard thrombus or soft thrombus and ensure that the operation is successfully completed.

In the expansion process of the thrombus taking support 40, the thrombus is continuously extruded by the thrombus taking support 40, so that the net rod 41 penetrates into the thrombus. It can be understood that if the width of the net rod 41 is too small, or the area of the grid 41 is too large, the radial supporting force of the thrombus removal stent 40 will be too small, which is not favorable for the net rod 41 to penetrate into the thrombus; if the width of the mesh rod 41 is too large or the area of the mesh 41 is too small, the radial supporting force of the embolectomy stent 40 is too large, the too large radial force has great damage to the inner wall of the blood vessel, and the embolectomy stent 40 is difficult to compress into the delivery sheath, which is not favorable for pushing out and recovering the embolectomy stent 40. Preferably, the width of the net rod 41 is 0.04 mm-0.2 mm, and the width of the net grid 41 isArea of 1mm²～3.5mm ²。

Referring to fig. 13, the sixth preferred embodiment of the present invention provides an embolectomy device 100, which is substantially the same as the embolectomy device of the first preferred embodiment, and comprises a push-pull guide wire 10 and a filter screen 20. The difference is that the embolectomy device 100 further comprises an expansion balloon 50, the proximal end of the expansion balloon 50 is connected with the push-pull guide wire 10, and the distal end is connected with the filter screen 20.

When the thrombus 200 is captured, the dilatation balloon 50 can be delivered to the thrombus 200 through a delivery sheath (not shown) with the filter mesh 20 at the distal end of the thrombus 200. Upon release from the delivery sheath, filter mesh 20 automatically returns to the predetermined configuration while dilation balloon 50 is inflated. The expansion saccule 50 can continuously extrude thrombus in the expansion process, so that the thrombus is dehydrated, the volume is reduced, the viscoelasticity of the dehydrated thrombus is enhanced, and the friction coefficient is increased, so that the thrombus is not easy to separate. In the process of withdrawing the thrombus, the thrombus and the expansion balloon 50 move relatively until the thrombus contacts the filter screen 20, and the filter screen 20 is provided with the clamping part 22, so that the clamping part 22 can clamp the thrombus 200, the combination between the thrombus 200 and the filter screen 20 is firmer, and the clamping part 22 can further dehydrate the thrombus in the process of extruding the thrombus, so that the thrombus can be conveniently taken out.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. The thrombus taking device comprises a filter screen and a push-pull guide wire connected with the filter screen, and is characterized in that the filter screen comprises a filter screen main body and a clamping part connected to the filter screen main body, one end, far away from the filter screen main body, of the clamping part extends towards the near end and towards one side close to a longitudinal central shaft, and the far end of the push-pull guide wire is fixedly connected with the near end of the filter screen main body.

2. The embolectomy device of claim 1, wherein a membrane is disposed within the filter screen.

3. The embolectomy device of claim 1, wherein the thickness of the clamping portion is 0.1mm to 3 mm.

4. The embolectomy device of claim 1, wherein the proximal end of the screen body and/or the distal end of the screen body is/are of a conical configuration having a taper of 30 ° -60 °.

5. The embolectomy device of claim 1, wherein the filter screen is a structure with two closed ends; or the near end of the filter screen is an open end, and the far end of the filter screen is a closed end.

6. The embolectomy device of claim 5, wherein the open end of the filter screen is provided with a support.

7. The embolectomy device of claim 1, wherein the clamping portion comprises an outer clamping layer and an inner clamping layer which are connected, the filter screen body comprises an outer body layer and an inner body layer, the outer body layer is connected with the outer clamping layer, and the inner body layer is connected with the inner clamping layer.

8. The embolectomy device of claim 1, wherein the filter screen further comprises a connecting portion, and the filter screen body is connected with the push-pull guidewire through the connecting portion.

9. The embolectomy device of any one of claims 1-8, wherein the embolectomy device further comprises an embolectomy support, and the push-pull guide wire is connected with the filter screen through the embolectomy support.

10. The embolectomy device of any one of claims 1-8, wherein the embolectomy device further comprises an expansion balloon, and the push-pull guide wire is connected with the filter screen through the expansion balloon.