WO2021197408A1

WO2021197408A1 - Bifurcated stent

Info

Publication number: WO2021197408A1
Application number: PCT/CN2021/084879
Authority: WO
Inventors: 董智慧; 符伟国; 刘浩; 李安伟; 王永胜
Original assignee: 杭州唯强医疗科技有限公司
Priority date: 2020-04-02
Filing date: 2021-04-01
Publication date: 2021-10-07

Abstract

Disclosed in the present application is a bifurcated stent, comprising a main body, a first branch and a second branch. The first branch and the second branch are connected to the same end of the main body; and the main body, the first branch and the second branch are all of a net structure. The bifurcated stent further comprises a bifurcated area connected between the first branch and the second branch, and the mesh density of the bifurcated stent in the bifurcated area is larger than that in other areas. Therefore, the contact area between the bifurcated area of the bifurcated stent and the blood vessel wall at the bifurcated position is increased, and the bifurcated area can support the blood vessel wall at the bifurcated position; and due to the fact that the mesh density of the bifurcated stent in the bifurcated area is larger than that in other areas, embolism caused by the detachment of mural thrombus at the bifurcated position is prevented.

Description

Bifurcated bracket

This application claims the priority of a Chinese patent application filed with the State Intellectual Property Office of China, with application numbers 202010256646.1 and 202020472400.3, and the application name "Fork Bracket" on April 02, 2020, the entire content of which is incorporated into this application by reference .

Technical field

This application relates to an implantable device for use in a patient, and in particular to a bifurcated stent.

Background technique

With the improvement of people's living standards and changes in lifestyles, the incidence of vascular diseases is getting higher and higher. If these diseases are not treated in time, they may cause vascular blockage, aneurysms and other diseases, which will seriously endanger human life.

At present, minimally invasive interventional procedures can be used to treat vascular diseases. Such methods have little trauma to patients, high safety, and high effectiveness. Therefore, they are affirmed by operators and patients and have become an important treatment method for vascular diseases. Interventional therapy refers to the use of a delivery system to implant a stent into the patient’s vascular diseased segment. The implanted stent can support the stenosis and occluded segment of the blood vessel or block the vascular dissection through expansion, reducing the elastic retraction and reshaping of the blood vessel, and maintaining the tube Smooth blood circulation in the cavity also has the effect of preventing restenosis.

Existing stents used to repair occlusive lesions of the main iliac artery (including stenosis lesions) are mostly conventional straight tube type or integrated bifurcated type. Among them, the conventional straight tube treatment requires more than one stent (such as a covered stent or a bare stent) to be placed in parallel or crossed. In this way, the stent is implanted, causing the guide wire to fail to use the "mounting technique" from the femoral artery. After crossing the bifurcation of the main iliac artery, it enters the contralateral limb blood vessel, so that the contralateral limb blood vessel cannot be treated. In addition, after some existing bifurcated stents are implanted in the bifurcation position of the abdominal aorta and the iliac artery, because the grid of the bifurcation stent is sparse in the bifurcation area, the mural thrombus at the bifurcation position of the abdominal aorta is likely to be trapped. The bifurcation area of the stent falls off and enters the circulatory system with the blood.

Summary of the invention

In order to solve the aforementioned problems, the present application provides a bifurcated bracket.

The present application provides a bifurcated stent, including a main body, a first branch and a second branch, the first branch and the second branch are both connected to the same end of the main body, the main body and the first branch And the second branch are both mesh structures, the bifurcation bracket further includes a bifurcation region connected between the first branch and the second branch, and the bifurcation bracket is in the bifurcation region The mesh density of is greater than the mesh density of other regions of the bifurcated bracket.

After the bifurcated stent provided by the present application is implanted in the bifurcation position of the abdominal aorta and the iliac artery, the main body is accommodated in the abdominal aorta, the first branch and the second branch are respectively accommodated in an iliac artery, and the bifurcation area It straddles between the two iliac arteries. The bifurcation stent provided in the present application increases the mesh density of the bifurcation area, on the one hand, it increases the contact area between the bifurcation area and the vascular wall at the bifurcation position of the iliac artery, and reduces the bifurcation position of the abdominal aorta. The risk of mural thrombus falling off and entering the circulatory system with blood. On the other hand, it is beneficial to increase the support force of the bifurcation area on the vessel wall at the bifurcation position of the blood vessel, and reduce the compression of the two branches of the bifurcation stent on the two iliac arteries. In addition, the bifurcated stent provided in the present application allows the guide wire to cross the main iliac artery from the femoral artery using the "mounting technique" and then enter the contralateral iliac artery, which is convenient for the operator to treat the blood vessels of the contralateral limb.

Description of the drawings

In order to more clearly describe 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. Obviously, the drawings in the following description are only These are some implementations of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative work.

FIG. 1 is a schematic diagram of the structure of the bifurcated bracket provided by the first embodiment of the application.

Fig. 2 is a schematic diagram of an application scenario of the bifurcated bracket provided in Fig. 1.

Fig. 3 is a schematic diagram of the weaving mode of the bifurcated stent shown in Fig. 1.

Fig. 4 is a partial structural diagram of the support ring of the bifurcated bracket shown in Fig. 3.

Fig. 5 is a partial structural diagram of the support ring in the modified embodiment of the bifurcation bracket shown in Fig. 3.

Fig. 6 is a partial enlarged schematic view of the bifurcated bracket shown in Fig. 3.

Fig. 7 is another partial enlarged schematic view of the bifurcated bracket shown in Fig. 3.

Fig. 8 is a schematic diagram of the three-dimensional structure of the bifurcated bracket shown in Fig. 1.

Fig. 9 is a partial enlarged schematic view of the bifurcated bracket shown in Fig. 1.

Fig. 10 is a bottom view of the structure of the bifurcated bracket shown in Fig. 8.

Fig. 11 is a schematic view of the bottom structure of the conventional bifurcation bracket when the bifurcation area is not encrypted.

FIG. 12 is a schematic diagram of the structure of the bifurcated bracket provided by the second embodiment of the application.

Fig. 13 is a bottom view of the structure of the bifurcated bracket shown in Fig. 12.

FIG. 14 is a bottom view of the structure of the bifurcated bracket provided by the third embodiment of this application.

Fig. 15 is a partial enlarged schematic view of the bifurcated bracket shown in Fig. 14.

FIG. 16 is a schematic structural diagram of a bifurcated bracket provided by the fourth embodiment of this application.

Fig. 17 is a bottom view of the structure of the bifurcated bracket shown in Fig. 16.

FIG. 18 is a schematic diagram of the structure of the bifurcated bracket provided by the fifth embodiment of this application.

Detailed ways

The technical solutions in the embodiments of the present application will be described clearly and completely in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all of them. Based on the implementation manners in this application, all other implementation manners obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of this application.

In this application, the term "proximal end" refers to the end close to the heart in the direction of blood flow, and "distal end" refers to the end away from the heart in the direction of blood flow; Defined as the axial direction.

The first embodiment

Please refer to FIG. 1, which is a schematic diagram of the structure of the bifurcated bracket provided by the first embodiment of the application.

The present application discloses a bifurcated bracket 100, which includes a main body 10, a first branch 30 and a second branch 50. The first branch 30 and the second branch 50 are both connected to the same end of the main body 10, the main body 10 and the first branch 30 Both the second branch 50 and the second branch 50 are in a mesh structure. The branch support 100 also includes a branch area 70 connected between the first branch 30 and the second branch 50. The dense parallel diagonal lines indicate the bifurcation region 70, but these diagonal lines are only used to indicate the location of the region, and are not used to limit the specific structure in the bifurcation region 70, such as the weaving method of the braided wire in the bifurcation region 70. In this application, the mesh density of the bifurcation stent 100 in the bifurcation region 70 is greater than the mesh density of other regions of the bifurcation stent 100. The other regions of the bifurcation bracket 100 are the remaining regions of the bifurcation bracket 100 except for the bifurcation region 70.

The bifurcated stent 100 provided in the present application can be used to be implanted into the bifurcation-iliac artery position of the abdominal aorta. Please refer to Figure 1 and Figure 2 in combination. After implantation, the main body 10 is housed in the abdominal aorta. The branch 30 and the second branch 50 are respectively housed in an iliac artery, and the bifurcation area 70 spans between the two iliac arteries. Since the bifurcation stent 100 provided in the present application has a greater mesh density in the bifurcation region 70 than in other regions of the bifurcation stent 100, on the one hand, the contact area between the bifurcation region 70 and the vascular wall at the bifurcation position of the iliac artery is increased. , It reduces the risk that the mural thrombus at the bifurcation position of the abdominal aorta falls off and enters the circulatory system with the blood. The two branches of the fork stent 100 (ie, the first branch 30 and the second branch 50) compress the two iliac arteries. In addition, the bifurcated stent 100 provided in the present application allows the guide wire to cross the bifurcation of the abdominal aorta from the femoral artery using the "mounting technique" and enter the contralateral iliac artery, which is convenient for the operator to treat the blood vessels of the contralateral limb. It can be understood that the above application scenarios are only exemplary and do not constitute a limitation of the present application. The bifurcation stent 100 provided in this embodiment can also be used to be implanted into any Y-shaped bifurcation formed by a main blood vessel and a branch blood vessel. During implantation, the bifurcation area 70 is placed between two branch blood vessels, the first branch 30 and the second branch 50 are respectively accommodated in the two branch blood vessels, and the main body 10 is accommodated in the main blood vessel.

In this embodiment, the length of the first branch 30 along the axial direction thereof is greater than the length of the second branch 50 along the axial direction thereof. The length of the second branch 50 along its axial direction is sufficient for the guide wire to cross the bifurcation position by using the "turning mountain technique" and then enter the contralateral iliac artery. It can be understood that the length of the first branch 30 along its axial direction is not limited to be greater than the length of the second branch 50 along its axial direction. For example, the length of the first branch 30 along its axial direction may be equal to or less than the length of the second branch 50 along its axis. The length of the direction.

In this embodiment, the bifurcation area 70 extends from the junction of the first branch 30 and the second branch 50 on the side of the first branch 30 close to the second branch 50 to the distal end of the first branch 30; and, The bifurcation area 70 extends from the junction of the first branch 30 and the second branch 50 on the side of the second branch 50 close to the first branch 30 to the distal end of the second branch 50. The distal end of the first branch 30 is the end of the first branch 30 away from the main body 10; the distal end of the second branch 50 is the end of the second branch 50 away from the main body 10. In one embodiment, the bifurcation area 70 extends from the junction of the first branch 30 and the second branch 50 on the side of the first branch 30 close to the second branch 50, and extends to a position close to the distal end of the first branch 30 , Or extend to the distal end of the first branch 30. In one embodiment, the bifurcation area 70 extends from the junction of the first branch 30 and the second branch 50 on the side of the second branch 50 close to the first branch 30, and extends to a position close to the distal end of the second branch 30 , Or extend to the distal end of the second branch 50.

It can be understood that in the modified embodiment, the shape of the bifurcation region 70 is not limited. For example, the bifurcation region 70 is a linear region connected between the first branch 30 and the second branch 50, or the bifurcation region 70 It is a strip-shaped area connected between the first branch 30 and the second branch 50. It can be understood that the extension range of the bifurcation area 70 is not limited. The bifurcation area 70 extends from the junction of the first branch 30 and the second branch 50, on the side of the first branch 30 close to the second branch 50, towards the first branch 30. And/or the bifurcation area 70 extends from the junction of the first branch 30 and the second branch 50, on the side of the second branch 50 close to the first branch 30, to the distal end of the second branch 50; and/or Or the case where the bifurcation area 70 extends from the junction of the first branch 30 and the second branch 50 to the main body 10 is within the protection scope of the present application.

In this embodiment, the main body 10, the first branch 30, and the second branch 50 each enclose a cavity, and the cavity of the first branch 30 and the cavity of the second branch 50 are all connected to the cavity of the main body 10 , The side of the main body 10, the first branch 30 and the second branch 50 facing the respective cavity is the inner side, and the side of the main body 10, the first branch 30 and the second branch 50 away from the respective cavity is the outer side.

In this embodiment, the main body 10, the first branch 30, and the second branch 50 all have a cylindrical shape. It can be understood that the main body 10, the first branch 30, and the second branch 50 are not limited to being cylindrical, and the shape of the main body 10, the first branch 30, and the second branch 50 to fit the inner wall of the blood vessel as much as possible is protected by the present application. Within range.

Please refer to FIGS. 1 and 3 together. The main body 10, the first branch 30, and the second branch 50 all include at least one support ring 61 arranged along their respective axial directions. The support ring 61 is an elastic metal support frame or an elastic non-metal, such as a polymer material support frame. In this embodiment, the support frame is a nickel alloy stent. The support ring 61 includes at least one sub-support ring, which is wave-shaped. When the number of the sub-support rings is multiple, the multiple sub-support rings surround the central axis of the main body 10, the first branch 30 or the second branch 50. Set up stacked or overlapped and interspersed. The sub-support ring includes a plurality of wave rods 612 connected in sequence, two wave rods 612 form a wave crest 614 at the connection of the proximal end, and two wave rods 612 form a wave trough 615 at the connection of the distal end.

A kind of weaving method of mesh structure is now provided, as follows:

As shown in FIG. 3, FIG. 3 shows a schematic diagram of the mesh structure of the first embodiment of the present application being expanded along a bus bar. In order to distinguish between different support rings 61, the three adjacent support rings in FIG. 3 are respectively denoted as The support rings 61A, 61B, and 61C, and the support rings 61A, 61B, and 61C are arranged in sequence from the proximal end to the distal end, and the support rings 61A, 61B, and 61C are located in the main body 10, the first branch 30 or the second branch 50. The bus bar is a line parallel to the respective axial direction on the side of the mesh structure of the main body 10, the first branch 30 or the second branch 50. The support rings 61A, 61B, and 61C may be part of the mesh structure in the main body 10, the first branch 30, or the second branch 50. The three

support rings

61A, 61B, and 61C are braided by a braided wire. In this embodiment, when weaving, firstly, the braided yarn starts from the starting point O1, and weaves along the sine wave path in the circumferential direction of the main body 10, the first branch 30 or the second branch 50, until the braided yarn reaches the starting point again. O1. Then, the braided wire extends in the direction of the support ring 61B to the junction of the support ring 61A and the support ring 61B, that is, the braided wire reaches the starting point O2 of the support ring 61B, and then follows the main body 10, the first branch 30 or the second branch. The circumferential direction of each 50 is woven according to a sine wave path, and the braiding of the support ring 61B is completed. By analogy, the braiding of the support ring 61C is completed. It can be understood that in this embodiment, the starting point O1 is a wave crest 614 of the supporting ring 61A, the starting point O2 is a wave trough 615 of the supporting ring 61A, and the starting point O2 is a wave crest 614 of the supporting ring 61B.

In the modified embodiment, the main body 10, the first branch 30 or the second branch 50 only includes one support ring 61A, and does not include the adjacent support rings 61B and 61C.

It can be understood that when the braided thread starts from the starting point O1, it is woven in a sine wave path along the respective circumferential directions of the main body 10, the first branch 30 or the second branch 50, until the braided thread reaches the starting point O1 again, the braided thread surrounds The number of turns of the central axis of the main body 10, the first branch 30, or the second branch 50 can be one or more than one turn. When the braided wire wraps around the central axis more than one turn, multiple turns are formed. The first sub-support ring, the second sub-support ring..., as shown in Figure 4, a circle of braided support rings covers the first braided sub-support ring, and the poles of each sub-support ring and the poles inside or outside Form a number of intersections. In two adjacent intersections, the poles of the sub-support ring on the outer side are all arranged outside the poles of the sub-support ring on the inner side. Specifically, the support ring 61 in FIG. 4 includes four sub-support rings formed by braided wire around the central axis four times. In order to distinguish the four sub-support rings, the four-circle support rings in FIG. 4 are respectively denoted as Q1, Q2, Q3, Q4. As mentioned above, the side of the main body 10, the first branch 30 and the second branch 50 facing the respective cavity is the inner side, and the side of the main body 10, the first branch 30 and the second branch 50 facing away from the respective cavity is the outer side. In FIG. 4, the inward direction along the paper is the inner side, and the outward direction along the paper is the outer side, and the sub-support rings Q1, Q2, Q3, and Q4 are sequentially stacked in the radial direction from the inner side to the outer side. The two adjacent intersections formed by the poles of the sub support ring Q4 and the poles of the sub support rings Q3 and Q2 are X1 and X2. The sub support ring Q4 is an outer sub support ring compared with the sub support rings Q3 and Q2. . In the adjacent intersections X1 and X2, the poles of the sub-support ring Q4 are woven outside the poles of the sub-support rings Q3 and Q2. The sub-supporting rings Q1, Q2, Q3, and Q4 may be located in the main body 10, the first branch 30, or the second branch 50.

In the embodiment shown in FIG. 5, at least one support ring in the bifurcated bracket 100 (the main body 10, the first branch 30, and the second branch 50) includes a first sub-support ring and other sub-support rings. The first sub-support The ring and other sub-support rings are arranged to overlap and intersect in the radial direction around the axis of the main body, the first branch or the second branch. The poles of the first sub-support ring and the poles of other sub-support rings form several intersection points, where There are at least a first intersection and a second intersection. At the first intersection, the poles of the first sub-support ring are arranged on the outside relative to the poles of the other sub-support rings that cross it, at the second intersection, The poles of the first sub-support ring are arranged on the inner side relative to poles of the other sub-support rings that cross it. At least one of the main body 10, the first branch 30, and the second branch 50 includes a support ring shown in FIG. 5. Specifically, the support ring described in FIG. 5 includes four sub-support rings formed by braided wire around the central axis four times. In order to distinguish the four sub-support rings, the four-circle support rings in FIG. 5 are respectively denoted as L1, L2 , L3, L4, in Figure 5, the inward direction along the paper surface is the inside, and the outward direction along the paper surface is the outside. The sub-supporting rings L1, L2, L3, L4 are arranged in a radial direction crosswise and stacked. The sub-supporting rings L1, L2, L3, and L4 each include a plurality of poles, and two adjacent intersections formed by the poles of the sub-supporting ring L4, the sub-supporting ring L3, and the poles of the sub-supporting ring L2 are Y1 and Y2. In one of the intersections Y1, the poles of the sub-support ring L4 are set on the outside of the poles of the sub-support ring L2, and at the other intersection Y2, the poles of the sub-support ring L4 are set on the sub-support ring L3. The inside of the pole. The sub-support ring L4 is at an intersection point Y1 with other sub-support rings, and the sub-support ring L4 is disposed closer to the outside relative to the sub-support ring that crosses it. At another adjacent intersection Y2, the sub-support ring L4 is opposite to The sub-support ring that crosses it is arranged close to the inner side, so as to achieve cross-stacking with other sub-support rings in the radial direction, which is beneficial to improve the overall supporting force and firmness of the support ring. In one embodiment, at the adjacent intersection formed by any one sub-support ring in the support ring and other sub-support rings, the sub-support ring is alternately arranged on the inner side and the outer side relative to the other sub-support rings that cross it.

It can be understood that the number of sub-support rings is not limited. For example, the number of sub-support rings is one or more. When the number of sub-support rings is one, there are no multiple-lap sub-support rings or overlapping sub-support rings. .

Please refer to FIGS. 3 and 6 in combination. FIG. 6 is a partial enlarged schematic diagram of the bifurcated bracket shown in FIG. 1.

In this embodiment, the crests 614 and troughs 615 between adjacent support rings are arranged corresponding to each other. For example, the crests 614 of the support ring 61A and the troughs (not shown) of the support ring 61B are arranged correspondingly, and the troughs 615 of the support ring 61A are arranged correspondingly. Corresponding to the wave crest 614 of the support ring 61B.

Taking the main body 10 as an example, in an embodiment in which the main body 10 has a plurality of support rings arranged sequentially along the axial direction, the support ring at the distal end is a support ring near one end of the first branch 30 or the second branch 50, and the main body 10 is Between adjacent support rings, the wave crest 614 of the distal support ring passes through the wave trough 615 of the proximal support ring from the inside to the outer side, so that the wave crest 614 of the distal support ring is hooked to the wave trough 615 of the proximal support ring. . For example, as shown in FIG. 6, when braiding the support ring 61B, the wave crest 614 of the support ring 61B penetrates from the inner side of the wave trough 615 of the support ring 61A and exits from the outer side of the wave trough 615 of the first support ring 61A. In this way, the wave crest 614 of the supporting ring 61B is hooked on the wave trough 615 of the supporting ring 61A. As shown in FIG. 7, when the support ring 61C is braided, the wave crest 614 of the support ring 61C penetrates from the inner side of the wave trough 615 of the support ring 61B and passes out from the outer side of the wave trough 615 of the support ring 61B. In this way, the support The wave crest 614 of the ring 61C is hooked on the wave trough 615 of the supporting ring 61B. Among them, the hooking positions between adjacent support rings are shown as circles in FIG. 3.

The foregoing is only an exemplary illustration of the connection between adjacent support rings in the main body 10. In this embodiment, the connection between adjacent support rings in the first branch 30 and the second branch 50 is the same as that in the main body 10. The connection between adjacent support rings is similar.

In this embodiment, the connection between the first branch 30 and the main body 10 and the connection between the second branch 50 and the main body 10 are the same as the connection between the adjacent support rings described above, that is, as shown in FIG. 10 and the first branch 30, the peak 614 of the support ring of the first branch 30 close to the main body 10 penetrates from the inside of the wave trough 615 of the support ring of the main body 10 close to the first branch 30, and from the support ring of the main body 10 The wave trough 615 penetrates outside, so that the support ring of the first branch 30 is hooked on the support ring of the main body 10. At the connection between the main body 10 and the second branch 50, the wave crest 614 of the support ring of the second branch 50 close to the main body 10 penetrates inside the wave trough 615 of the support ring of the main body 10 close to the second branch 50, and from the support of the main body 10 The wave trough 615 of the ring penetrates outside, so that the support ring of the second branch 50 is hooked on the support ring of the main body 10, so that the wave crest 614 of the support ring of the first branch 30 and/or the second branch 50 and the support ring of the main body 10 The trough 615 is connected. It can be understood that when the crest 614 of the first branch 30 or the second branch 50 passes through the trough 615 of the main body 10 from the inner side to the outer side, or when passing through the trough 615 of the support ring of the main body 10 from the outer side to the inner side, the braided wire may be The wave trough 615 of the support ring of the main body 10 is wound multiple times to further increase the mesh density of the bifurcation bracket 100 at the bifurcation area 70 and improve the blocking effect.

It can be understood that in the modified embodiment, whether it is between adjacent support rings of the main body 10, the first branch 30 and the second branch 50, or the connection between the main body 10 and the first branch 30, or the main body 10 and the second branch 50 Between adjacent support rings at the connection, the wave crest 614 of the distal support ring can also pass through the wave trough 615 of the proximal support ring from the outside to the inside. It can be understood that the wave crest 614 of the support ring at the distal end is not limited to be hooked to the trough 615 of the support ring at the proximal end. For example, the wave crest 614 of the support ring at the distal end can be welded to the trough 615 of the support ring at the proximal end.

It can be understood that the mesh structure provided by the above weaving method is only exemplary, and the number of support rings is not limited by the above, for example, the number of support rings may be one or more.

It can be understood that it is not limited that the multiple support rings are braided by one braided wire. For example, each support ring can be braided from more than one braided wire.

It can be understood that the material of the braided wire is not limited. For example, the braided wire can be, but is not limited to, made of metal materials such as nickel-titanium alloy wire, cobalt-based alloy wire, or stainless steel wire, and the braided wire can also be made of polymer materials.

In this embodiment, the mesh structure of the main body 10, the first branch 30, and the second branch 50 are each woven by one braided wire, that is, the entire bifurcated stent 100 is braided by three wires. It can be understood that the entire bifurcated stent 100 is not limited to be made of wire braiding. For example, the bifurcated stent 100 can be but not limited to be cut by laser.

In this embodiment, the braided node between every two wires is compressed by a steel sleeve. It can be understood that it is not restricted that every braided node between two wires is compressed by a steel sleeve.

Please refer to FIGS. 1 and 8 in combination. FIG. 8 is a schematic diagram of the three-dimensional structure of the bifurcated bracket shown in FIG. 1. It should be noted that FIG. 8 only exemplarily shows the mesh structure of a part of the area, and the mesh structure of other areas is not shown.

In this embodiment, the first branch 30 and the second branch 50 both include a connecting portion 63 and a body portion 65 that are integrally connected. The body portion 65 is generally cylindrical, and at least part of the connecting portion 63 is funnel-shaped and connected to the body portion. 65 and the main body 10. The bifurcation area 70 is at least partially disposed on the connecting portion 63.

In this embodiment, the first branch 30 is taken as an example. A support ring of the first branch 30 close to the main body 10 forms a connecting portion 63. At least part of the connecting portion 63 is funnel-shaped, that is, along the main body 10 to the first branch 30. The outer diameter of the funnel-shaped part of the connecting portion 63 gradually decreases, and the connecting portion 63 serves as a transition between the main body 10 and the first branch 30. The main body portion 65 is generally cylindrical, and is used to support the inner wall of the branch blood vessel. In the application scenario, the main body 10 is used to be implanted into a main blood vessel, and the first branch 30 or the second branch 50 is used to be implanted into a branch blood vessel. The inner diameter of the branch blood vessel is narrower than that of the main blood vessel. The transition position between the blood vessel and the main blood vessel often has a section of the inner diameter of the blood vessel, and the main blood vessel gradually narrows toward the branch blood vessel. In the present application, the connecting portion 63 is provided so that the connecting portion 63 can be attached to the inner wall of the blood vessel at the transition position of the branch blood vessel and the main blood vessel.

It can be understood that when the number of the support ring of the first branch 30 or the second branch 50 is one, the part of the support ring close to the main body 10 is the connecting part 63 and at least partly has a funnel shape, and the part of the support ring away from the main body 10 is the body part. 65 and cylindrical.

In this embodiment, the mesh structures of the first branch 30 and the second branch 50 are both woven from the distal end to the proximal end. When woven to the last support ring of the first branch 30 or the second branch 50, that is, When woven to the connecting part 63, the crest 614 of the first branch 30 or the second branch 50 passes through the trough 615 of the main body 10 from the inside to the outside, that is, at the junction of the connecting part 63 and the main body 10, the first branch 30 or the second branch 30 The crest 614 of the branch 50 is hooked to the trough 615 of the main body 10. It can be understood that the first branch 30 and/or the second branch 50 can also be braided from the proximal end to the distal end.

It can be understood that the situation where the first branch 30 and/or the second branch 50 includes the connecting portion 63 is within the protection scope of the present application.

Please refer to FIGS. 8, 9 and 10 together. FIG. 9 is a partial enlarged schematic view of the bifurcation area of the bifurcation bracket shown in FIG. 1. Fig. 10 is a bottom view of the structure of the bifurcated bracket shown in Fig. 8.

It is worth noting that the mesh structure of the first branch 30 in the bifurcation area 70 and the mesh structure of the second branch 50 in the bifurcation area 70 are entangled with each other. More specifically, in the bifurcation area 70, the connecting part 63 of the first branch 30 is close to the wave rod 612 on the side of the second branch 50, and the connecting part 63 of the second branch 50 is close to the wave on the side of the first branch 30. The rods 612 are wound around each other. In this embodiment, in the bifurcation area 70, the pole 612 of the second branch 50 penetrates from the inner side of the pole 612 of the first branch 30 and exits from the outer side of the pole 612 of the first branch 30, making the first branch 30 The poles 612 of the branch 30 and the poles 612 of the second branch 50 are entangled with each other to shorten the distance between the two poles 612 of the first branch 30 and the second branch 50 in the bifurcation area 70, so that the bifurcation The mesh density of the stent 100 in the bifurcation region 70 is greater than the mesh density of other regions of the bifurcation stent 100. In this way, compared to the conventional bifurcated stent shown in FIG. 11, the bifurcated area between the first branch 30a and the second branch 50a is not covered by braided wires to form a hollow area, the bifurcated stent provided in the present application 100 (shown in Figure 10) because the hollow area of the bifurcation area 70 is blocked by the intertwined wave rods 612, the mural thrombus at the location of the bifurcation area 70 is not easily detached from the bifurcation area 70 and flows to it with blood. In other positions, the contact area between the bifurcation region 70 of the bifurcation stent 100 and the blood vessel wall at the bifurcation position is increased, so that the intertwined wave rods 612 provide support for the blood vessel wall at the bifurcation position.

It can be understood that the number of poles 612 that are entangled with each other is not limited to two, and the number of poles 612 that are entangled with each other can be, but is not limited to, multiple. For example, in a modified embodiment, a plurality of poles 612 can also be interspersed Entangled.

Second embodiment

Please refer to FIGS. 12 and 13 together. FIG. 12 is a schematic diagram of the structure of the bifurcation bracket provided by the second embodiment of the application, and FIG. 13 is a schematic diagram of the structure of the bifurcation bracket shown in FIG. 12 when viewed from below.

The main difference between the bifurcation bracket 300 provided in this embodiment and the bifurcation bracket 100 provided in the first embodiment is that the bifurcation bracket 300 provided in this embodiment further includes a connector 390, which is connected to the first branch. Between the mesh structure of 330 and the second branch 350, the mesh density of the bifurcation bracket 300 in the bifurcation region 370 is greater than the mesh density of other regions of the bifurcation bracket 300.

It can be understood that the connection member 390 is not limited to be connected between the mesh structure of the first branch 330 and the second branch 350. For example, the connection member 390 may also be connected between the first branch 330 and the main body 310, or the connection member 390 may also be connected between the first branch 330 and the main body 310. It can be connected between the second branch 350 and the main body 310, and the connector 390 can also be arranged in the bifurcation area 370. The grid density of the connector 390 in the bifurcation area 370 is greater than the grid density in other areas of the bifurcation bracket. If the connector 390 also includes an area outside the bifurcation area 370, the mesh density of the connector 390 in the bifurcation area 370 is still greater than the mesh density distributed outside the bifurcation area 370, so that the bifurcation The mesh density of the stent 300 in the bifurcation region 370 is greater than the mesh density of other regions of the bifurcation stent 300.

In this embodiment, the connecting member 390 is a mesh structure arranged in the bifurcation region 370, and the mesh density of the connecting member 390 is greater than the mesh density of other regions of the bifurcation bracket 300. It can be understood that the mesh density of the connecting member 390 is not limited to the same everywhere. For example, a larger mesh density may be set in the part of the connecting member 390 located in the bifurcation area 370, and in the part of the connecting member 390 located outside the bifurcation area 370. Set a smaller mesh density.

In this embodiment, the connecting member 390 is woven integrally with the first branch 330 and the second branch 350.

It can be understood that the connecting piece 390 is not limited to the integrated weaving of the first branch 330 and the second branch 350. For example, the connecting piece 390 may be, but not limited to, a pre-woven mesh patch, which is fixed by stitching or fixing with wires. The mesh patch is connected between the mesh structures of the first branch 330 and the second branch 350.

The third embodiment

Please refer to FIGS. 14 and 15 in combination. FIG. 14 is a schematic bottom view of the structure of the bifurcation stent provided by the third embodiment of this application; FIG. 15 is a partial enlarged schematic diagram of the bifurcation stent shown in FIG. 14.

The main difference between the bifurcated bracket 400 provided in this embodiment and the bifurcated bracket 300 provided in the second embodiment is that: the connecting member 490 of the bifurcated bracket 400 is a winding wire, which is used to connect to the first branch 430 and Between the mesh structure of the second branch 450. Specifically, the winding wire is fixedly connected between the two wave rods 4612 of the first branch 430 and the second branch 450.

Understandably, the number of winding wires is not limited. For example, the number of winding wires can be, but is not limited to, multiple. It can be understood that the winding wire meets at least one of the following conditions. At least one winding wire is connected between the mesh structure of the first branch 430 and other winding wires, and at least one winding wire is connected to the mesh structure of the second branch 450 and other winding wires. Between the winding wires, at least one winding wire is connected between the other winding wires.

Fourth embodiment

Please refer to FIGS. 16 and 17 in combination. FIG. 16 is a schematic structural diagram of the bifurcated bracket provided by the fourth embodiment of this application; FIG. 17 is a schematic structural diagram of the bifurcated bracket shown in FIG. 16 viewed from below.

The main difference between the bifurcation stent 500 provided in this embodiment and the bifurcation stent 100 provided in the first embodiment is that the bifurcation area 570 also extends from the junction of the first branch 530 and the second branch 550 to the main body 510. The bifurcation stent 500 includes a first membrane 110 covering the bifurcation area 570. The mesh density of the first membrane 110 is greater than that of other regions of the bifurcation stent 500, so that the mural thrombus at the branch location of the blood vessel is not easy It falls off from the bifurcation area 570 covered by the first covering film 110.

The first covering film 110 may be made of polyester cloth, PTFE, PET, or other polymer materials.

In this embodiment, the first covering film 110 is sutured and fixed between the pole 5612 of the first branch 530 and the pole 5612 of the second branch 550 to block the bifurcation area 570.

It can be understood that the first covering film 110 is not limited to be fixed in the bifurcation area 570 by stitching. For example, the first covering film 110 may be but not limited to be fixed in the bifurcation area 570 by bonding.

Fifth embodiment

As shown in FIG. 18, the main difference between the bifurcated stent 600 provided in this embodiment and the bifurcated stent 500 provided in the fourth embodiment is that the bifurcated stent 600 also includes a second covering film 120. It is arranged at the junction of the main body 610 and the first branch 630 shown in FIG. 18, wherein the mesh density of the first covering film 110 is greater than the mesh density of the second covering film 120, so that the mural thrombus is not easy to escape from the second covering film. The area covered by the film 120 falls off. The second covering film 120 may be made of polyester cloth, PTFE, PET or other polymer materials.

It can be understood that the position of the second covering film 120 is not limited, and the case where the bifurcation bracket 600 is further provided with the second covering film 120 outside the bifurcation area 670 is within the protection scope of the present application.

Within the scope of the technical principle of the present application, the specific technical solutions in the above embodiments may be mutually applicable, and will not be repeated here.

What is disclosed above is only the preferred embodiments of this application, and of course it cannot be used to limit the scope of rights of this application. Therefore, equivalent changes made according to the claims of this application still fall within the scope of this application.

Claims

A bifurcation stent, characterized in that it comprises a main body, a first branch and a second branch, the first branch and the second branch are both connected to the same end of the main body, the main body, the first branch The branches and the second branches are both mesh structures. The bifurcation bracket further includes a bifurcation area connected between the first branch and the second branch. The grid density of the region is greater than the grid density of other regions of the bifurcated bracket.
The bifurcated stent according to claim 1, wherein:

The bifurcation area extends from the junction of the first branch and the second branch, on the first branch, on the side close to the second branch, and extends to the distal end of the first branch; and/ or

The bifurcation area extends from the junction of the first branch and the second branch, on the second branch, on the side close to the first branch, and extends to the distal end of the second branch; and/ or

The bifurcation area extends from the junction of the first branch and the second branch to the main body.
The bifurcated stent according to claim 2, wherein the first branch and/or the second branch includes a connecting portion disposed at the proximal end, and at least part of the connecting portion is funnel-shaped and connects the At the distal end of the main body, the bifurcation area is at least partially disposed on the connecting portion.
The bifurcation stent according to any one of claims 1 to 3, wherein the mesh structure of the first branch in the bifurcation area and the mesh structure of the second branch in the bifurcation area The structures are entangled with each other, so that the mesh density of the bifurcation stent in the bifurcation region is greater than the mesh density of the other regions of the bifurcation stent.
The bifurcation stent according to any one of claims 1 to 3, wherein the bifurcation stent further comprises a connecting member arranged in the bifurcation area, and the connecting member is connected to the first branch Between the mesh structure of the second branch and the second branch, the mesh density of the bifurcation stent in the bifurcation region is greater than the mesh density of other regions of the bifurcation stent.
The bifurcated stent according to claim 5, wherein:

The connecting member is a mesh structure, and the mesh density of the connecting member is greater than the mesh density of other regions of the bifurcation bracket; or, the connecting member includes at least one winding wire, and the winding wire satisfies at least one of the following Conditions: at least one of the winding wires is used to connect between the mesh structure of the first branch and the second branch, and at least one of the winding wires is connected to the mesh structure of the first branch and other Between the winding wires, at least one of the winding wires is connected between the mesh structure of the second branch and the other winding wires, and at least one of the winding wires is connected between the other winding wires .
The bifurcated stent according to any one of claims 1 to 3, wherein the bifurcated stent further comprises a first membrane covering the bifurcation area, and the mesh density of the first membrane is It is greater than the mesh density of other regions of the bifurcated bracket.
The bifurcated stent according to claim 7, wherein the bifurcated stent is further provided with a second covering film outside the bifurcation area, and the mesh density of the first covering film is greater than that of the second covering film. The mesh density of the film.
The bifurcated stent according to any one of claims 1 to 3, wherein the mesh structure of the main body, the first branch and the second branch all comprise at least one support arranged along their respective axial directions. The support ring is wavy and forms wave crests and wave troughs, and the wave crests of the support ring of the first branch and/or the second branch are connected with the wave troughs of the support ring of the main body.
The bifurcated stent according to claim 9, wherein the main body, the first branch and the second branch each enclose a cavity, and the cavity of the first branch and the The cavity of the second branch communicates with the cavity of the main body, the side of the main body, the first branch, and the second branch facing the respective cavity is the inner side, the main body, the first branch, and the The side of the second branch away from the respective cavity is the outside;

At the connection between the main body and the first branch and the second branch, the wave crests of the support ring of the first branch and/or the second branch pass through the support ring of the main body from the inside to the outside The trough of the wave, or the trough of the support ring passing through the main body from the outside to the inside; and/or

Between adjacent support rings of the main body, the wave crest of the distal support ring passes through the wave trough of the proximal support ring from the inner side to the outer side, or passes through the wave trough of the proximal support ring from the outer side to the inner side; and/or

Between the adjacent support rings of the first branch and/or the second branch, the wave crest of the distal support ring passes through the wave trough of the proximal support ring from the inside to the outside, or passes through the proximal support ring from the outside to the inside. The trough of the support ring at the end.
The bifurcation stent according to claim 10, wherein each support ring includes at least one sub-support ring, and the sub-support ring includes a plurality of poles connected in sequence, and the two poles are close to each other. A wave crest is formed at the junction of the ends, and a wave trough is formed at the junction of the two wave rods.
The bifurcated bracket according to claim 11, wherein at least one of the support rings in the bifurcated bracket includes a first sub-support ring and a second sub-support ring, and the first sub-support ring and the second sub-support ring The second sub-support ring surrounds the axial direction of the main body, the first branch or the second branch, and is arranged in a stack in a radial direction.
The bifurcated bracket according to claim 11, wherein at least one of the support rings in the bifurcated bracket includes a first sub-support ring and other sub-support rings, and the first sub-support ring and the Other sub-support rings are arranged to overlap and intersect in the radial direction around the axial direction of the main body, the first branch or the second branch. The poles form several intersections, of which there are at least a first intersection and a second intersection. At the first intersection, the poles of the first sub-support ring are relative to the other sub-support rings that cross it. The poles are arranged on the outer side, and at the second intersection, the poles of the first sub-support ring are arranged on the inner side relative to the poles of the other sub-support rings intersecting with the pole.