WO2023015652A1

WO2023015652A1 - Thrombus removal device

Info

Publication number: WO2023015652A1
Application number: PCT/CN2021/117585
Authority: WO
Inventors: 夏顺; 刘载淳; 黄定国
Original assignee: 上海腾复医疗科技有限公司
Priority date: 2021-08-09
Filing date: 2021-09-10
Publication date: 2023-02-16

Abstract

A thrombus removal device (1), comprising: a thrombus filtering net bag (10), a connecting stent (11), and a thrombus breaking net bag (12). The thrombus filtering net bag (10), the connecting stent (11), and the thrombus breaking net bag (12) are all of radial self-expansion support structures. A distal end of the thrombus filtering net bag (10) is closed, and a proximal end of the thrombus filtering net bag (10) is an opening end capable of being supported on the inner wall of the blood vessel in the circumferential direction, and the opening end of the thrombus filtering net bag (10) is connected to a distal end of the connecting stent (11). A distal end of the thrombus breaking net bag (12) can be supported on the inner wall of the blood vessel in the circumferential direction, and is connected to a proximal end of the connecting stent (11). The connecting stent (11) forms a thrombus capture area in an unfolded state. The thrombectomy device (1) can improve the success rate of one-time thrombus removal, and can better prevent the broken thrombus from escaping, so that thrombus removal is more thorough.

Description

A thrombectomy device

cross reference

This application refers to the Chinese patent application No. 2021218447710 entitled "A Thromb Removal Device" submitted on August 9, 2021, which is fully incorporated into this application by reference.

technical field

The present application relates to the technical field of medical devices, in particular to a thrombectomy device.

Background technique

Intravascular thrombosis is a systemic disease with a very wide range of pathogenesis, which may affect the upper and lower extremities, visceral vessels and carotid arteries. When thrombus occurs in the heart, myocardial infarction can occur; if it occurs in the brain, it can cause cerebral infarction; if it occurs in the lungs, it can cause pulmonary embolism... According to statistics, deaths caused by thrombotic diseases account for 51% of the global death toll , far exceeding the deaths caused by tumors, infectious diseases, and respiratory diseases.

At present, the main treatment methods for thrombosis include: anticoagulant drug therapy, interventional operation treatment and surgical operation. For patients with mild symptoms, anticoagulant drugs can be used for conservative treatment; for patients who cannot be treated by drugs, necessary surgery must be taken. Compared with surgery, interventional therapy has less trauma, faster recovery, and is more acceptable to patients. The effect of interventional therapy is more limited by interventional devices.

The inventors found that: due to the diversity of thrombosis disease sites and the complexity of thrombus morphology, existing thrombus removal devices, such as thrombus removal stents, suction catheters, etc., generally have difficulty in completely removing thrombus, low success rate of one-time thrombus removal, and Fragmented thrombus is easy to escape and block the distal branch.

Contents of the invention

The purpose of some embodiments of the present application is to provide a thrombus removal device to solve the problems of low success rate of one-time thrombus removal and easy omission of fragmented thrombus.

An embodiment of the present application provides a thrombus removal device, including: a thrombus filter bag, a connecting bracket, and a thrombus crushing mesh bag; the thrombus filtering mesh bag, connecting bracket, and the thrombus crushing mesh bag are radially self-expanding stent structures; The distal end of the thrombus filter mesh bag is closed, and the proximal end is an open end that can be supported on the inner wall of the blood vessel along the circumferential direction, and its open end is connected to the distal end of the connecting bracket; the distal end of the thrombus crushing mesh bag can be supported circumferentially It is located on the inner wall of the blood vessel and connected with the proximal end of the connecting stent; the connecting stent forms a thrombus trapping area in the unfolded state.

In addition, the thrombus filtering mesh bag, the connecting bracket and the thrombus crushing mesh bag are integrally woven with memory metal wires.

In addition, the thrombectomy device further includes: a bracket tightening ring; the bracket tightening ring is sheathed on the connecting bracket.

In addition, the stent constricting ring is a developing ring.

In addition, the connecting bracket includes: a first bracket segment located between the opening end of the thrombus filtering net bag and the bracket constricting ring, and a second bracket segment located between the stent constricting ring and the thrombus crushing net bag Two stent segments; the first stent segment includes: a plurality of twisted rods that are braided by the braided wires of the thrombus filter bag at its open end, and the plurality of twisted rods are formed along the opening end of the thrombus filter bag Evenly distributed in the circumferential direction; the second stent segment includes: a plurality of twist rods that are woven from the braided wires of the thrombus crushing mesh bag at its open end, and the plurality of twist rods are woven along the length of the thrombus crushing mesh bag The open ends are evenly spaced circumferentially.

In addition, the number of twisted rods of the second stent segment is an even multiple of the number of twisted rods of the first stent segment, and the thrombus crushing net bag is made of several strands of metal wire interlaced, and each strand of metal wire has an even number of wires. .

In addition, the thrombus filtering mesh pocket is umbrella-shaped in the unfolded state, and its mesh density gradually decreases from the distal end to the proximal end.

In addition, the thrombus crushing mesh bag is a mesh bag unit, and the mesh bag unit is dome-shaped; or the thrombus crushing mesh bag includes a plurality of mesh bag units connected in sequence from the distal end to the proximal end, and each mesh bag unit has a middle diameter. The large end has a smooth transitional net structure with a small diameter, and the net unit at the proximal end is disc-shaped.

In addition, the thrombus removal device further includes: a distal developing ring disposed at the distal end of the thrombus filtering net bag and a proximal developing ring disposed at the proximal end of the thrombus crushing net bag; the distal developing ring is also used for collecting The wire at the far end of the thrombus filtering mesh bag is bundled and fixed; the proximal developing ring is also used to bundle and fix the metal wire at the proximal end of the thrombus crushing mesh bag.

In addition, the thrombus removing device further includes: a guide head and a push tube; the proximal end of the guide head is connected to the far end of the distal developing ring, and the distal end of the pushing tube is connected to the proximal developing ring. Proximally connected.

The thrombus retrieval device of the embodiment of the present application is released to the distal end of the thrombus and then automatically unfolds. When the thrombus retrieval device is withdrawn, the thrombus crushing net cuts and crushes the thrombus, and the fragmented thrombus enters the thrombus filter mesh through the thrombus capture area , so that the crushed thrombus can be more thoroughly collected into the sheath tube, which not only improves the success rate of thrombus removal at one time, but also makes it difficult for the crushed thrombus to escape, thereby facilitating more thorough removal of the thrombus.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. It can be understood that the accompanying drawings in the following description It is only an embodiment of the present application, and those skilled in the art can also obtain other drawings according to the provided drawings without creative work.

Figure 1 is a schematic structural view of a thrombectomy device provided in an embodiment of the present application;

Fig. 2 is another structural schematic diagram of the thrombus removal device provided by the embodiment of the present application;

Fig. 3 is a schematic structural diagram of the mesh density of the thrombus filter bag of the thrombus removal device provided by the embodiment of the present application;

Fig. 4 is a schematic structural view of the twist rod of the connecting bracket of the thrombectomy device provided in the embodiment of the present application;

Fig. 5 is a schematic structural diagram of a thrombectomy device provided in an embodiment of the present application used in conjunction with a delivery system.

Detailed ways

In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, various implementations of the present application will be described in detail below in conjunction with the accompanying drawings. However, those of ordinary skill in the art can understand that, in each implementation manner of the present application, many technical details are provided for readers to better understand the present application. However, even without these technical details and various changes and modifications based on the following implementation modes, the technical solution claimed in this application can also be realized.

Unless otherwise specified, the proximal end and the distal end mentioned in this application have the same meaning in terms of orientation, that is, in the state of use, the distal end is the end away from the operator, the proximal end is the end close to the operator, and the operator is at the proximal end. Control the thrombectomy device.

The embodiment of the present application provides a thrombectomy device 1 for rapid removal of thrombus in a blood vessel. The thrombectomy device can be used in conjunction with the delivery system shown in Figure 5, such as preloaded into the sheath tube 7 of the delivery system shown in Figure 5. As shown in FIG. 1 , the thrombus removal device 1 includes: a thrombus filtering mesh bag 10 , a connecting bracket 11 and a thrombus crushing mesh bag 12 . The thrombus filtering mesh bag 10, the connecting bracket 11 and the thrombus crushing mesh bag 12 are all radially self-expanding stent structures.

The distal end of the thrombus filter bag 10 is closed, and the proximal end is an open end capable of being supported on the inner wall of the blood vessel in the circumferential direction, and the open end is connected to the distal end of the connecting bracket 11 . The thrombus filtering net bag 10 can filter and collect broken thrombi.

The distal end of the thrombus breaking mesh bag 12 can be supported on the inner wall of the blood vessel along the circumferential direction, and is connected with the proximal end of the connecting bracket 11 . The thrombus crushing net bag 12 can cut and break the thrombus into smaller thrombi, which can be conveniently collected into the thrombus filtering net bag.

The connecting stent 11 forms a thrombus trapping area in the unfolded state, and after the fragmented thrombus fills in, it is collected into the thrombus filter bag 10 .

The thrombus filtering net bag 10, the connecting bracket 11 and the thrombus crushing net bag 12 can be integrally woven with memory metal wires, so that each of the aforementioned braided structures has good radial self-expandability and shape memory capability. It can be understood that the thrombus filtering net bag 10 , the connecting bracket 11 and the thrombus crushing net bag 12 can also be made by laser cutting process, which is not specifically limited here.

The thrombus filtering mesh bag 10 can be made of multiple memory metal wires, such as nickel-titanium alloy wires interlaced, and specifically, a single metal wire can be interlaced to form an umbrella-shaped mesh bag structure, which is gradually reduced in diameter from the open end to the distal end. Sleek transition net pocket structure. The opening end of the thrombus filter bag 10 has a large diameter, and after expansion, it can be well attached and supported on the inner wall of the blood vessel, and can move along the inner wall of the blood vessel. During the withdrawal process of the thrombus filter bag 10, the fragmented thrombus can be collected into the thrombus along the inner wall of the blood vessel. In the filter bag, it can better prevent thrombus from being missed. Simultaneously, the blood flow can also pass through the thrombus filtering mesh bag 10 .

Optionally, the mesh density of the thrombus filtering mesh bag 10 may gradually decrease from the distal end to the proximal end. Specifically, the thrombus filtering net bag 10 can be divided into multiple density segments in the axial direction, and the number of density segments of the thrombus filtering net bag 10 can be determined according to its length. As shown in FIG. 3 , the thrombus filtering mesh bag 10 is divided into three density segments along the axial direction, and the mesh density of the three density segments gradually decreases from the distal end to the proximal end. The mesh structure of the thrombus filtering net bag 10 can not only catch the thrombus well, but also reduce its sheathing resistance. In one example, the lengths of the plurality of density segments may gradually decrease from the distal end to the proximal end, that is, the density segment with the highest mesh density at the farthest end has the longest length, so as to better prevent thrombus from escaping. This embodiment does not specifically limit the mesh density distribution structure of the thrombus filter bag, the mesh density of the thrombus filter bag 10 can be the same, or the lengths of different density sections can be the same, as long as the thrombus filtering effect and sheath retraction performance can be guaranteed That's it. Compared with the thrombus filter mesh bag 10 made by the laser cutting process, the weaving process can not only finely adjust the mesh density, but also has better softness and lower cost.

The thrombectomy device 1 also includes a distal developing ring 3 disposed at the distal end of the thrombus filter bag 10 for marking the position of the distal end of the thrombectomy device 10 . Simultaneously, the far-end developing ring 3 can also be used for converging and fixing the wire at the far end of the thrombus filter mesh pocket 10, killing two birds with one stone.

The thrombus crushing mesh bag 12 and the thrombus filtering mesh bag 10 are an integral weaving structure of memory metal wires. The thrombus crushing net bag 12 is made of interlaced memory metal wires. The interlaced metal wires form a rhombus grid, which is convenient for cutting and crushing thrombus. In this embodiment, there is no specific limitation on the shape of the grid.

As shown in FIG. 1 , the thrombus crushing net 12 can be a net unit, which is dome-shaped and has an open end, and the open end can support and attach to the inner wall of a blood vessel. The diameter of the opening end of the thrombus crushing net bag 12 is large, and a smooth transition net bag structure with a diameter gradually decreasing is formed from its opening end to the proximal end.

The braided wires of the thrombus crushing mesh bag 12 are gathered and woven at the opening end to form a plurality of twist rods 110 evenly spaced along the circumference of the opening end. The braided structure of the twist rods 110 is shown in FIG. 4 .

The thrombectomy device 1 can also include a proximal developing ring 4 for marking the proximal position of the thrombus removing device, and the proximal wire of the thrombus crushing mesh bag 12 can be fixed by the proximal developing ring 4 after being bundled.

In some examples, the thrombus breaking net 12 may include a plurality of net units connected in sequence from the distal end to the proximal end. Wherein, the net bag unit adjacent to the connecting bracket 11 is dome-shaped, and the net bag unit far away from the connecting bracket 11 is disc-shaped. As shown in Figure 2, the thrombus crushing net bag 12 includes two net bag units, respectively the distal net bag unit 120 connected to the proximal end of the connecting bracket 11 and the proximal net bag unit connected to the proximal end of the distal net bag unit 120 121. The distal net unit 120 is a smooth transition net structure whose diameter gradually decreases from the far end to the proximal end, and the proximal net unit 121 is a smooth transition net structure with a large middle diameter and small diameters at both ends. Wherein, the transition of the distal net bag unit 120 is relatively gentle, so that the distal net bag unit 120 is in the shape of a dome or an umbrella. The transition of the proximal net bag unit 121 is relatively steep, making it a disc-shaped structure. When the disc-shaped proximal mesh unit 121 is withdrawn, it can provide a thrombus cutting surface relatively perpendicular to the axial direction of the blood vessel, and can quickly break up the thrombus. Multiple mesh pocket units can crush the thrombus multiple times, so as to achieve a better thrombus crushing effect. The thrombus crushing net bag 12 can also collect a part of the broken thrombus.

Please continue to refer to FIG. 1 and FIG. 2 , the thrombectomy device 1 may further include: a bracket tightening ring 2 , and the bracket tightening ring 2 is sheathed on the connecting bracket 11 , that is, it is sheathed on a plurality of twist rods 110 after being bundled.

Optionally, the stent constricting ring 2 is a developing ring, that is, the stent constricting ring 2 also has a developing function, which can be used to mark the position of the thrombus capture area.

The connecting bracket 11 includes: a first bracket segment located between the opening end of the thrombus filtering net bag 10 and the bracket constricting ring 2 , and a second bracket segment located between the stent constricting ring 2 and the thrombus crushing net bag 12 . The first support segment and the thrombus filtering mesh bag 10 form a three-dimensional rhombus structure, and the second support segment and the mesh bag unit adjacent thereto form a three-dimensional rhombus structure. The first support section includes: a plurality of twist rods 110 woven by the braided wires of the thrombus filtering mesh bag 10 gathered at its opening end, and the plurality of twist stems 110 are evenly spaced along the circumference of the opening end of the thrombus filtering mesh bag 10 . The second support section includes: a plurality of twist rods 110 that are gathered and woven at the open end of the thrombus crushing mesh bag 12 by braiding wires, and the plurality of twist rods 110 are evenly spaced along the circumference of the opening end of the thrombus crushing mesh bag 12 . As shown in FIG. 4 , each twist rod can be braided by three strands of braided wire, and each strand of braided wire can contain multiple metal wires.

Due to the constricting effect of the stent constricting ring 2, the connecting stent 11 forms a sparse stent structure with a large diameter at both ends and a small diameter in the middle. The sparse stent structure forms a thrombus capture area, which can facilitate the filling and entry of fragmented thrombus. In the expanded state, the twisted rod 110 connecting the stent 11 will not be attached to the inner wall of the blood vessel, which can prevent thrombus from being missed due to being squeezed on the blood vessel wall. When withdrawing, part of the thrombus can quickly enter the thrombus capture area, and be collected into the sheath containing the thrombus removal device 1 . Openings are formed between the multiple twisted rods 110 of the first stent segment, through which fragmented thrombi can smoothly enter the thrombus filter bag 10, and the thrombus filter bag 10 brings all the thrombus into the sheath.

In some examples, the second bracket segment may also adopt a net structure similar to the distal net unit 120 . The use of twist rod structure can not only simplify the weaving process, but also because the twist rod structure can provide a larger opening, it is beneficial for thrombus to enter the thrombus crushing net bag.

The number of twist rods of the second stent segment is an even multiple of the number of twist rods of the first stent segment, and the thrombus crushing net bag 12 is made of several strands of metal wires interlaced, and each strand of metal wires has an even number of wires. For example, the number of twist rods in the second stent segment is twice the number of twist rods in the first stent segment. As shown in Figures 1 and 2, the number of twisted rods in the first bracket section is 4, and the number of twisted rods in the second bracket section is 8. There are more twist rods 110 in the second support section, and more braided nodes can be formed in the circumferential direction of the opening end of the thrombus crushing net bag 12, and the braided wires dispersed from more braided nodes can be easily interlaced to form thrombus Broken net bag12. At the same time, there are two braiding wires in each of any two interlaced braiding wires of the thrombus crushing net bag 12. By merging multiple braiding wires for interlacing weaving, it is not only convenient for the thrombus crushing net bag to weave a larger grid structure, but also satisfies Thrombus crushing requirements, and can improve the strength of thrombus crushing net bag, is conducive to crushing harder thrombus. The number of twisted rods in the first stent section is less, which can facilitate the insertion of the thrombus filter into the sheath. The twist rods of the first bracket segment and the second bracket segment may be arc-shaped rods.

The thrombectomy device 1 may further include: a guide head 5 and a push tube 6 . The distal end of the guide head 5 is a pointed end, and the proximal end of the guide head 5 is connected with the distal end of the distal developing ring 3, so as to facilitate the advancement of the thrombus removal device in the blood vessel. The far end of the push tube 5 is connected to the near end of the near end developing ring 4 . The mesh bag structure of the thrombectomy device 1 can be pushed out of the sheath or retracted into the sheath by operating the pushing tube 5 .

With reference to accompanying

drawings

1 and 5, the method and steps of using the thrombectomy device in the embodiment of the present application are as follows:

In the interventional surgery for pulmonary embolism to remove thrombus, percutaneous puncture under local anesthesia was used to establish an instrument intervention channel in the femoral vein of the affected side. After the guide wire is sent to the position passing through the thrombus, the thrombectomy device according to the embodiment of the present application is guided by the guide wire, and travels to the pulmonary embolism in the blood vessel cavity. The sheath tube of the device thrombectomy device 1 is withdrawn, so that the thrombus crushing mesh bag is released at the distal end of the thrombus. And withdraw the thrombectomy device as a whole. During the withdrawal process, the thrombus is cut, squeezed and fragmented under the external force of the thrombus crushing net bag. With the withdrawal of the thrombus retrieval device, the fragmented thrombus enters the thrombus capture area, and then Enter the thrombus filtering mesh bag 10 again, and finally be taken out of the body.

Based on the above technical solutions, the embodiments of the present application at least have the following advantages and positive effects:

The thrombus retrieval device 1 of the embodiment of the present application is automatically deployed after being released to the distal end of the thrombus. When the thrombus retrieval device 1 is withdrawn, the thrombus crushing net cuts and crushes the thrombus, and the fragmented thrombus enters the thrombus capture area, and then The thrombus filter bag is wrapped around the blood vessel wall and then put into the sheath, which not only improves the success rate of one-time thrombus removal, but also makes it difficult to miss the thrombus, so that the thrombus can be removed more thoroughly.

Those of ordinary skill in the art can understand that the above-mentioned implementation modes are specific examples for realizing the present application, and in practical applications, various changes can be made to it in form and details without departing from the spirit and spirit of the present application. scope.

Claims

A thrombus removal device, characterized in that it includes: a thrombus filter bag, a connecting bracket, and a thrombus crushing mesh bag;

The thrombus filtering mesh bag, the connecting bracket and the thrombus crushing mesh bag are radially self-expanding stent structures;

The distal end of the thrombus filter bag is closed, and the proximal end is an open end that can be supported on the inner wall of the blood vessel in the circumferential direction, and its open end is connected to the distal end of the connecting bracket;

The distal end of the thrombus fragmentation net can be supported on the inner wall of the blood vessel in the circumferential direction, and connected to the proximal end of the connecting bracket;

The connecting stent forms a thrombus trapping area in a deployed state.
The thrombectomy device according to claim 1, wherein, the thrombus filtering mesh bag, the connecting bracket and the thrombus crushing mesh bag are integrally woven with memory metal wires.
The thrombectomy device according to claim 2, wherein the thrombectomy device further comprises: a stent constricting ring;

The stent constricting ring is sheathed on the connecting stent.
The thrombectomy device according to claim 3, wherein the stent constricting ring is a developing ring.
The thrombectomy device according to claim 3, wherein the connecting bracket comprises: a first bracket segment located between the opening end of the thrombus filter bag and the bracket constricting ring, and a first bracket segment located between the bracket constricting ring. a second stent segment between the ring and the thrombus-disrupting mesh;

The first support section includes: a plurality of twist rods woven by the braided wires of the thrombus filter bag at its open end, and the plurality of twist rods are evenly spaced along the circumference of the open end of the thrombus filter bag distributed;

The second stent section includes: a plurality of twist rods woven by the braided wires of the thrombus crushing net at its opening end, and the plurality of twist rods are evenly spaced along the circumference of the opening end of the thrombus crushing net distributed.
The thrombectomy device according to claim 5, wherein the number of twisted rods of the second stent section is an even multiple of the number of twisted rods of the first stent section, and the thrombus crushing net is made of several strands of metal wires interlaced Braided with an even number of wires per strand.
The thrombectomy device according to claim 1, wherein the thrombus filter mesh bag is umbrella-shaped in an unfolded state, and its mesh density gradually decreases from the distal end to the proximal end.
The thrombectomy device according to claim 1, wherein the thrombus crushing net is a net unit, and the net unit is dome-shaped; or

The thrombus crushing mesh bag includes a plurality of mesh bag units sequentially connected from the distal end to the proximal end; wherein, the mesh bag unit adjacent to the connecting bracket is in the shape of a dome, and the mesh bag unit far away from the connecting bracket is in the shape of a disc.
The thrombus removal device according to claim 2, wherein, the thrombus removal device further comprises: a distal developing ring disposed at the distal end of the thrombus filtering net bag and a proximal developing ring disposed at the proximal end of the thrombus crushing net bag ;

The distal developing ring is also used to bundle and fix the wire at the distal end of the thrombus filter bag;

The proximal developing ring is also used to bundle and fix the metal wire at the proximal end of the thrombus crushing mesh bag.
The thrombectomy device according to claim 9, wherein the thrombus retrieval device further comprises: a guide head and a push tube;

The proximal end of the guide head is connected to the distal end of the distal developing ring,

The distal end of the push tube is connected with the proximal end of the proximal developing ring.