Covered stent

Abstract

The present application relates to a covered stent, which comprises a main stent and a branch stent, wherein the main stent comprises a branch port in communication with the branch stent; the branch stent comprises a first end and a second end opposite each other, the first end being connected to the branch port; and the branch stent comprises an adjustment section close to the first end and a support section close to the second end, the adjustment section comprising a reinforcing rib to enable the support section to be driven to sink when the branch stent is subjected to force. In the covered stent according to the present application, the reinforcing rib is arranged at the adjustment section to enable the support section to be driven to sink when the branch stent is subjected to force, thereby providing a covered stent that can flexibly adjust the positioning and reduce the requirement for the positioning accuracy of the stent, without affecting the blood flow of the aorta and branch arteries and without affecting the construction of a branch guidewire.

Description

Stent graft Technical Field

[0001] The present application belongs to the field of medical device technology, and specifically relates to a stent graft. Background Art

[0002] Branch stent reconstruction technology has become one of the mainstream technologies for intracavitary branch reconstruction. However, the current branch stent reconstruction technology has the following two major difficulties: first, the positioning accuracy of the stent with branches is required to be high; second, although the positioning accuracy requirement of the stent with internal branches can be reduced when the external branch stent is connected, the internal branch stent occupies the main cavity space and affects the hemodynamics of the main cavity. Summary of the Invention

[0003] A technical problem solved by the present application is how to provide a covered stent that can flexibly adjust its positioning and reduce the requirements for stent positioning accuracy without affecting the blood flow of the aorta and branch arteries, and without affecting the construction of the branch guidewire.

[0004] The present application provides a coated stent, which includes a main stent and a branch stent, the main stent including a branch port connected to the branch stent, the branch stent including a first end and a second end relative to each other, the first end being connected to the branch port, the branch stent including an adjustment section close to the first end and a support section close to the second end, the adjustment section including reinforcing ribs so that the support section can be driven to sink when the branch stent is subjected to force.

[0005] In one embodiment, the adjustment section further includes a connecting membrane connecting the branch port and the supporting section, and the reinforcing rib is provided on the connecting membrane, and the reinforcing rib is a flexible reinforcing rib.

[0006] In one embodiment, the reinforcing ribs are in a "chain-like" breakpoint structure or a broken section structure.

[0007] In one embodiment, the reinforcing rib includes a first section and a second section along its extension direction, and a gap is provided between the first section and the second section.

[0008] In one embodiment, the reinforcing rib comprises a suture line sewn along the connecting membrane;

[0009] Alternatively, the connecting film includes a folded portion, and the folded portion is hot-pressed to form the reinforcing rib;

[0010] Alternatively, the connecting film includes a folded portion, the reinforcing rib includes the folded portion and a suture line, and the suture line is sutured along the folded portion to form the reinforcing rib.

[0011] In one embodiment, at least two reinforcing ribs are arranged at intervals along the circumference of the branch support.

[0012] In one embodiment, the branch support includes a first circumferential support member arranged along the circumference of the branch support, and the first circumferential support member is arranged at the connection between the adjustment section and the support section.

[0013] In one embodiment, the branch support further includes a second circumferential support member and a third circumferential support member, wherein the second circumferential support member is disposed at the first end, and the third circumferential support member is disposed at the second end.

[0014] In one embodiment, the diameter of the first circumferential support member is defined as D1, the diameter of the second circumferential support member is defined as D2, and the diameter of the third circumferential support member is defined as D3, and D1, D2, and D3 satisfy: D1≤D3<D2;

[0015] Alternatively, D1, D2, and D3 satisfy: D1≤D3, and 1.5D1≤D2≤3D1.

[0016] In one embodiment, the reinforcing rib includes a first end and a second end, the first end is close to the first end, the second end is close to the second end, and a gap is provided between the first end and the first end of the branch bracket and / or a gap is provided between the second end and the adjustment section.

[0017] A technical effect of an embodiment of the present application is that the present application provides reinforcing ribs in the adjustment section so that the support section can be driven to sink when the branch stent is subjected to force, thereby providing a covered stent that can flexibly adjust the positioning and reduce the stent positioning accuracy requirements without affecting the blood flow of the aorta and branch arteries, and without affecting the construction of the branch guide wire. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] FIG1 is a schematic structural diagram of a stent graft provided in the present application;

[0019] FIG2 is a schematic structural diagram of a branch bracket provided in this application;

[0020] FIG2a is a schematic structural diagram of another branch stent provided in this application;

[0021] FIG2 b is a schematic structural diagram of another branch bracket provided in the present application;

[0022] FIG3 is a top view of FIG2 ;

[0023] FIG4 is a schematic structural diagram of another branch bracket provided in this application;

[0024] FIG5 is a schematic diagram of a branch stent of the stent graft provided in FIG1 sinking into the main stent cavity after being subjected to the force shown by F1 in FIG1;

[0025] FIG6 is a schematic diagram of a branch stent of the stent graft provided in FIG1 sinking into the main stent cavity after being subjected to the force shown by F2 in FIG1;

[0026] FIG7 is a schematic structural diagram of another branch bracket provided in the present application;

[0027] FIG8 is an enlarged view of point A in FIG7 ;

[0028] FIG9 is an enlarged view of another embodiment of point A in FIG7 ;

[0029] FIG10 is a top view of FIG9;

[0030] FIG11 is an enlarged view of another embodiment of point A in FIG7 ;

[0031] FIG12 is a top view of FIG11;

[0032] FIG13 is a top view of a branch bracket provided by the present application (viewed from the second end to the first end of the branch bracket);

[0033] FIG14 is a schematic diagram of the first section of the branch support provided in FIG13 when it is flipped down;

[0034] FIG15 is a schematic diagram showing FIG14 with the second section also turned down;

[0035] FIG16 is a schematic diagram showing the support section tilting relative to the second section based on FIG14;

[0036] FIG17 is a schematic diagram of the micro "cradle-type" structure based on FIG14 , which is translated and swung toward the left side of the figure;

[0037] FIG17a is a schematic top view of the branch bracket in FIG17;

[0038] FIG18 is a schematic diagram of the micro "cradle-type" structure based on FIG14 , which is translated and swung toward the right side of the figure;

[0039] FIG18a is a schematic top view of the branch bracket in FIG18;

[0040] FIG19 is a schematic structural diagram of an aortic arch stent provided in the present application;

[0041] FIG20 is a schematic structural diagram of a chest and abdomen main support provided by the present application;

[0042] Figure 21 is a schematic diagram of the structure of an abdominal main stent provided by the present application. 100, coated stent; 10, main stent; 11, branch port; 12, first bare wave ring; 13, main wave ring; 14, main body coating; 20, branch stent; 20a, first end; 20b, second end; 21, adjustment section; 211, connecting membrane; 2111, folding portion; 212, reinforcing rib; 212a, first section; 212b, second section; 2121, first end; 2122, second end; 22, support section; 22a, proximal end; 22b, distal end; 221, supporting coating; 222, supporting wave ring; 23, first circumferential support member; 24, second circumferential support member; 25, third circumferential support member; DETAILED DESCRIPTION

[0043] To facilitate understanding of the present application, a more comprehensive description of the present application will be provided below with reference to the accompanying drawings. The accompanying drawings illustrate preferred embodiments of the present application. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and comprehensive understanding of the disclosure of the present application.

[0044] It should be noted that when an element is referred to as being "fixed to" another element, it may be directly on the other element or there may also be an intermediate element. When an element is considered to be "connected" to another element, it may be directly connected to the other element or there may be an intermediate element at the same time. The terms "inside", "outside", "left", "right" and similar expressions used herein are for illustrative purposes only and do not represent the only implementation method. The axial direction of the branch stent defined in this application refers to the direction along the tubular extension of the branch stent, and the radial direction of the branch stent is perpendicular to its axial space; the axial direction of the main stent refers to the direction along the tubular extension of the main stent.

[0045] The present application provides a coated stent 100, as shown in Figure 1, the coated stent 100 includes a main stent 10 and a branch stent 20, the main stent 10 is a tubular structure with openings at both ends, including a first bare wave ring 12, a main wave ring 13 and a main coating 14, wherein the main wave ring 13 includes multiple main wave rings 13, and the multiple main wave rings 13 are arranged along the axial direction of the main stent 10 and are connected by the tubular main coating 14. The number of main wave rings 13 can be reasonably set according to the axial length of the main stent 10 and the wave height of the wave ring, and avoid the branch opening 11, so that the branch stent 20 can be connected to the branch opening 11, and the main cavity of the main stent 10 is connected to the cavity of the branch stent 20.

[0046] The axial length of the main bracket 10 can be set to: 40mm~240mm, the first bare wave ring 12 is arranged on the proximal end side of the main body wave ring 13, and is connected to the proximal edge of the main body coating 14; in other embodiments, the first bare wave ring 12 may also not be set. In this case, the proximal end of the coating is the proximal end of the main bracket 10.

[0047] In this embodiment, the main body coil 13 is disposed on the outside of the main body covering 14. When implanted in a blood vessel, this can enhance the friction between the main stent 10 and the inner wall of the blood vessel, thereby preventing the main stent 10 from shifting or shortening relative to the inner wall of the blood vessel. In other embodiments, the main body coil 13 can also be disposed on the inside of the main body covering 14, or the main body coil 13 can be disposed partially on the inside and partially on the outside of the main body covering 14, without limitation.

[0048] As shown in Figure 1-2, the branch bracket 20 includes a first end 20a and a second end 20b relative to each other. The first end 20a can be sutured and connected to the branch opening 11 of the main bracket 10 along its circumference by sutures. The branch bracket 20 also includes an adjustment section 21 and a support section 22. The adjustment section 21 is close to the first end 20a of the branch bracket 20, and the support section 22 is close to the second end 20b of the branch bracket 20, wherein the support section 22 includes a support coating 221 and a support wave ring 222, and the support coating 221 is covered on the inner or outer side of the support wave ring 222. The edge of the support wave ring 222 close to the first section 212a is flush or almost flush with the edge of the support coating 221 on the same side, and the edge of the support wave ring 222 close to the second end 20b is flush or almost flush with the edge of the support coating 221 on the same side, wherein almost flush means that the edge misalignment does not exceed 1mm, so that the support wave ring 222 has a better support effect on the edge of the support section 22.

[0049] As shown in Figures 2-3, the adjustment section 21 includes a connecting membrane 211 and a reinforcing rib 212 provided on the connecting membrane 211. In this embodiment, the adjustment section 21 is connected to the support section 22, and the connecting membrane 211 connects the branch port 11 and the support section 22. The support coating 221 is connected to the connecting membrane 211 to form the branch coating of the branch stent 20. The support wave ring 222 includes at least one wavy ring, which extends in a wavy manner along the circumference of the tubular support coating 221 (i.e., the circumference of the branch stent 20) to support the support coating 221 while maintaining the lumen of the branch stent 20. In this embodiment, the length of the branch stent 20 along its axial direction ranges from 5 mm to 40 mm, wherein the length of the adjustment section 21 in the axial direction of the branch stent 20 ranges from 3 mm to 20 mm; and the length of the support section 22 in the axial direction of the branch stent 20 ranges from 2 mm to 20 mm.

[0050] In this embodiment, the reinforcing rib 212 extends on the connecting membrane 211 from the first end 20a toward the second end 20b, or the reinforcing rib 212 extends from the second end 20b toward the first end 20a. The extension direction here only indicates the extension direction of the length of the reinforcing rib 212 and does not indicate the starting and ending directions of the reinforcing rib 212 when extending, so that when the second end 20b of the branch bracket 20 or the side of the branch bracket 20 is subjected to force, the reinforcing rib 212 provides support to the connecting membrane 211, so that the reinforcing rib 212 rotates relative to the first end 20a, thereby driving the support section 22 to at least partially sink to the adjustment section 21, and at the same time prevents the connecting membrane 211 from stacking in the axial direction due to the connecting membrane 211 being too soft to provide support along the axial direction of the branch bracket 20. If the connecting membrane 211 of the adjustment section 21 is stacked in the axial direction of the branch bracket 20, when constructing the branch guidewire, the stacked connecting membrane 211 will easily make it difficult for the branch guidewire to move forward.

[0051] In other embodiments, the other portions of the reinforcing rib, other than those connected to the connecting membrane at both ends, may be suspended from the connecting membrane, and may also serve as support for the connecting membrane in the axial direction of the branch stent, so as to facilitate rotation of the reinforcing rib relative to the first end. As shown in Figures 2-3, the support segment 22 may be a tubular structure of equal diameter, comprising a distal portion 22b distal to the main stent 10 and a proximal portion 22a proximal to the main stent 10, wherein the distal portion 22b and the proximal portion 22a are concentric and of equal diameter so that the support segment 22 forms a tubular lumen of equal diameter. In other embodiments, the support section 22 may also be a tubular structure of non-uniform diameter; when the support section 22 is a tubular structure of non-uniform diameter, the annular opening diameter of the proximal end 22a of the support section 22 is less than or equal to the annular opening diameter of the distal end 22b of the support section 22 (i.e., the second end 20b end of the branch bracket 20). As shown in Figure 4, the support section 22 may be an inverted frustum-shaped structure with a diameter gradually increasing from the proximal end 22a toward the distal end 22b, and the angle α between the side of the support section 22 and the axial direction of the branch bracket 20 is less than or equal to the angle β between the side of the adjustment section 21 and the axial direction of the branch bracket 20, so that after the support section 22 sinks into the downward-turned adjustment section 21, there is still excess space in the downward-turned adjustment section 21 for the support section 22 to tilt circumferentially and swing flexibly; the support section 22 may also be a drum-shaped structure with a large diameter in the middle and small diameters at both ends, which makes it more conducive to the support section 22 sinking relative to the adjustment section 21, and facilitates the support section 22 to flexibly rotate along the circumference of the branch bracket 20.

[0052] As shown in Figures 2-3 and 5 in conjunction with Figure 1, when the second end 20b of the branch stent 20 is subjected to a downward force from above as shown in Figure 1, the direction of the force is shown by arrow F1 in Figure 1, and the reinforcing rib 212 of the adjustment section 21 rotates relative to the first end 20a, causing the adjustment section 21 to rotate from the outside of the main stent 10 toward the inside of the main stent 10, thereby driving the support section 22 to sink into the lumen of the main stent 10 as a whole. As shown in Figure 5, since the sunken support section 22 can flexibly swing, when the branch guidewire passes through the sunken support section 22, according to the direction of the branch guidewire, the support section 22 can be pulled by the branch guidewire, causing the support section 22 to tilt toward the branch vessel orifice. In this embodiment, the adjustment section 21 and the support section 22 can also be set to have equal heights in the axial direction of the branch stent 20. When the adjustment section 21 turns toward the lumen of the main stent 10, while driving the support section 22 to sink, the second end 20b of the branch stent 20 just sinks to be flush with the side of the main stent 10, as shown in Figure 5. In other embodiments, the height of the adjustment segment 21 in the axial direction of the branch stent 20 can be set to be greater than the height of the support segment 22 in the axial direction of the branch stent 20, so that the branch stent 20 sinks into the cavity of the main stent 10, thereby avoiding the situation where the branch stent 20 is squeezed due to the narrow space of the aortic true lumen.

[0053] As shown in Figure 6 in combination with Figure 1, when the branch bracket 20 is subjected to lateral force, as shown in the direction of arrow F2 in Figure 1, the reinforcing rib 212 on the opposite side of the force point rotates relative to the corresponding position of the first end 20a, so that the adjustment section 21 on the opposite side of the force point (the right side of the branch bracket 20 in Figure 1) drives the support section 22 on that side to sink, so that the adjustment section 21 tilts toward the opposite side (right side) of its force point (the left side of the branch bracket 20 in Figure 1), as shown in Figure 6. Among them, the adjustment section 21 does not have a circumferential corrugated support member, so when the second end 20b or the side of the branch bracket 20 is subjected to force, the adjustment section 21 cannot be pressed down because the lumen of the adjustment section 21 is a fixed tube. The reinforcing rib 212 is extended in this direction. Combined with the flexibility of the connecting membrane 211, the adjustment section 21 can be at least partially folded into the cavity of the main bracket 10 due to force to facilitate adjusting the direction of the second end 20b port of the branch bracket 20, or the support section 22 can be sunken axially along the branch bracket 20 and close to the main bracket 10 or even as a whole sunken into the cavity of the main bracket 10. Since the support section 22 has its own support, it is only close to the cavity of the main bracket 10 in position while maintaining its original shape.

[0054] As shown in Figure 7, the branch bracket 20 includes a first circumferential support member 23 arranged along the circumference of the branch bracket 20. The first circumferential support member 23 is arranged at the connection between the adjustment section 21 and the support section 22. In this embodiment, the first circumferential support member 23 can be formed by suturing along the circumference of the connection using sutures. The support coating 221 and the connecting membrane 211 can be two separate membranes sewed together using sutures, or they can be an integrated membrane, and then sutured along the circumference at the boundary between the two. The first circumferential support member 23 can be continuous suture along the circumference or intermittent suture, which is not limited here. It is only necessary to form a support other than the membrane sutured along the circumference at the connection; in other embodiments, the first circumferential support member 23 can be a plurality of discontinuous developing arcs arranged at intervals along the circumference, or a continuous developing ring, and then the developing arc or developing ring is sutured at the connection with sutures to provide support other than the membrane at the connection. When the circumferential support member is a discontinuous arc, its diameter is the diameter of the circle corresponding to the arc. The branch bracket 20 also includes a second circumferential support member 24 and a third circumferential support member 25. The second circumferential support member 24 is arranged at the first end 20a of the branch bracket 20 (that is, the end of the adjustment section 21 away from the support section 22), and the third circumferential support member 25 is arranged at the second end 20b of the branch bracket 20 (that is, the end of the support section 22 away from the adjustment section 21, that is, the distal end 22b of the support section 22); the diameter of the first circumferential support member 23 is defined as D1, the diameter of the second circumferential support member 24 is D2, and the diameter of the third circumferential support member 25 is D3, wherein D1, D2 and D3 satisfy: D1≤D3<D2, so that the adjustment section 21 can flip toward the inner cavity of the main bracket 10, thereby driving the adjustment section 21 to sink, and also facilitating the sinking support section 22 to swing freely in the circumferential direction of the branch bracket 20 relative to the first circumferential support member 23. Among them, the setting of the first circumferential support member 23 has a circumferential supporting force between the adjustment section 21 and the support section 22. On the one hand, the first circumferential support member 23 is equivalent to presetting a fold between the adjustment section 21 and the support section 22, so that when the branch bracket 20 is subjected to force, the relative folding between the adjustment section 21 and the support section 22 is more crisp when the adjustment section 21 flips toward the direction close to the main bracket 10, and prevents the connection membrane 211 from stacking, so that the folding position of the adjustment section 21 close to the support section 22 side is controllable; the adjustment section 21 takes the first end 20a as the fulcrum towards It is folded in the direction close to the main support 10, so that the end of the adjustment section 21 close to the support section 22 sinks, thereby driving the support section 22 to sink. At the same time, in terms of relative position, the adjustment section 21 is folded toward the support section 22 relative to the connection between the two (the first circumferential support member 23); on the other hand, the first circumferential support member 23 can better maintain the annular shape of its proximal end portion 22a in the process of driving the support section 22 to sink, thereby preventing the annular shape of the proximal end portion of the support section from being affected by the lack of wave ring support in the adjustment section, thereby facilitating the reconstruction of the branch guidewire.The second circumferential support member 24 and the third circumferential support member 25 also respectively increase the support of the first end 20a and the second end 20b of the branch stent 20. In other embodiments, any circumferential support member of the first circumferential support member 23, the second circumferential support member 24 and the third circumferential support member 25 can be a continuous ring or a plurality of arc-shaped intervals, and can be sutured with sutures and wrapped in the coating to support the coating opening in a ring shape.

[0055] The first circumferential support member 23, the second circumferential support member 24, and the third circumferential support member 25 can also be configured with a developing material, such as tantalum wire, to further facilitate the formation of the branch stent 20 by the downward-turned adjustment segment 21 and the downward-turned support segment 22, providing good visualization in vivo and facilitating superselective reconstruction of the branches. In this embodiment, when the first circumferential support member 23 and the third circumferential support member 25 are provided, the supporting wave ring 222 can respectively abut the circumferential support member on the same side of the branch stent 20 at both ends in the axial direction of the branch stent 20 to better maintain the stent shape of the support segment 22, as shown in Figure 7.

[0056] In this embodiment, as shown in Figure 2 and Figure 7, the support section 22 is a tubular structure of equal diameter, that is, D1=D3; the adjustment section 21 is a hollow frustum-like structure, that is, D1<D2, and the projections of the first circumferential support member 23 and the third circumferential support member 25 on the radial cross-section of the branch bracket 20 do not exceed the projection of the second circumferential support member 24 on the radial cross-section of the branch bracket 20, so that the adjustment section 21 is not obstructed when turning toward the inner cavity of the main bracket 10, thereby smoothly driving the adjustment section 21 to sink, and also facilitating the sinking support section 22 to swing freely in the circumferential direction of the branch bracket 20 relative to the first circumferential support member 23. Furthermore, D1 and D2 also satisfy: 1.5D1≤D2≤3D1. When the size difference at both ends of the adjustment section 21 is too small, it may cause the adjustment section 21 to be not conducive to the adjustment section 21 being turned inward toward the main bracket 10 cavity relative to the first end 20a of the branch bracket 20. When the size difference at both ends of the adjustment section 21 is too large, it is not convenient for the shape setting of the adjustment section 21. When D1 and D2 satisfy 1.5D1≤D2≤3D1, it is more conducive to the shape setting of the adjustment section 21, and when the branch bracket 20 is subjected to force, the adjustment section 21 is turned inward toward the cavity of the main bracket 10.

[0057] In this embodiment, four reinforcing ribs 212 are evenly arranged along the circumference of the branch bracket 20. As shown in Figure 3, the central angle between two adjacent reinforcing ribs 212 is 90°, which allows the sunken support section 22 to swing freely within a range of 360° around the axial direction of the branch bracket 20 (along the circumference of the branch bracket 20) with its proximal end portion 22a as the base; in other embodiments, 1 to 16 reinforcing ribs 212 can be provided. When at least two reinforcing ribs 212 are provided, the reinforcing ribs 212 are arranged at intervals along the circumference of the branch bracket 20, and are evenly spaced, so that the reinforcing ribs 212 of the branch bracket 20 are evenly distributed in the circumferential direction.

[0058] In this embodiment, the reinforcement rib 212 is a flexible reinforcement rib 212. On the one hand, it can ensure that when the second end 20b of the branch bracket 20 is subjected to a small force, the branch bracket 20 can also be ensured to sink. On the other hand, when the support segment 22 sinks and is then subjected to a lateral force, when the support segment 22 tilts toward one side, the reinforcement rib 212 on the force-bearing side needs to partially return to the unturned state to support its "tilted" shape, as shown in Figure 5-6 combined with 1. Therefore, the flexible reinforcement rib 212 can make the support segment 22 tilt and swing in any circumferential direction, and the swinging process is more flexible, that is, the shape, support or softness of the reinforcement rib 212 affects whether the swinging process of the support segment 22 is smooth and flexible.

[0059] The reinforcing rib 212 can be in a "chain-like" breakpoint structure or a broken section structure. In one embodiment, a suture line is sewn on the connecting membrane 211 in the direction from the first end 20a toward the second end 20b, as shown in Figures 7-8. The suture line forms one of the reinforcing ribs 212. When the suture line is sewn, similar broken sections or breakpoint structures are generally formed on either side of the suture. On the other hand, since the suture line is relatively soft, when the suture line is used for suture, even if the suture line is sutured continuously or sutured back and forth for a few circles, it still has a certain flexibility. In other embodiments, the connecting membrane 211 includes a folding portion 2111. The folding portion 2111 is formed into a ridge-type reinforcing rib 212 by hot pressing the folding portion 2111 together. The folding portion 2111 can also be directly hot pressed on the adjacent connecting membrane 211 surface. The folding portion 2111 can also be formed not in the direction of hot pressing, but by sewing the suture line and the folding portion 2111 into one body through stitching to form a ridge-type reinforcing rib 212, as shown in Figures 9-12. Among them, when suturing, the suture line can be passed around the folding part 2111, and the folding part 2111 can be sutured on the connecting membrane 211, as shown in Figure 10, or it can be sutured at the root of the folding part 2111, and the line can be routed and passed around the folding part 2111 so that the folding part 2111 is placed in a ridge shape on the connecting membrane 211, as shown in Figure 12. The specific routing method of the suture line and whether it is continuous are not limited. It is only necessary to extend the reinforcement rib 212 along the direction of the first end 20a and the second end 20b on the connecting membrane 211 to form a ridge-like non-rigid, non-rotatable reinforcement support; and the extension line of the formed ridge does not need to be in the same plane as the tubular center axis of the branch bracket, it only needs to extend along the direction of the first end and the second end, which can be a straight extension, a curved extension, or a spiral extension, as long as it can be achieved that when the branch bracket is subjected to force, the reinforcement rib rotates relative to the first end toward the direction of the main bracket, thereby driving the support section to sink.

[0060] In other embodiments, as shown in FIG2a , the reinforcing rib 212 may further include a conical small wave ring 2123, and the wave height h of the conical small wave ring 2123 and the wave height H of the supporting wave ring 222 satisfy: H / 5≤h≤H / 2. The conical small wave ring includes a large head end and a small head end, the conical small wave ring 2123 close to the support section end is the small head end, and the conical small wave ring 2123 away from the support section end is the large head end, the wave ring diameter of the conical small wave ring 2123 close to the support section 22 end is smaller than the wave ring diameter away from the support section 22, that is, the wave ring diameter of the small head end is smaller than the wave ring diameter of the large head end, and the wave height h of the conical small wave ring 2123 is smaller than the wave height H of the supporting wave ring 222, when the second end 20b of the branch bracket 20 or the side of the branch bracket 20 When subjected to force, the reinforcing ribs 212 provide support to the connecting membrane 211, making it easy for the reinforcing ribs 212 to rotate relative to the first end 20a, thereby driving the support section 22 to at least partially sink to the adjustment section 21, and at the same time preventing the connecting membrane 211 from stacking in the axial direction due to the connecting membrane 211 being too soft to provide support along the axial direction of the branch stent 20. If the connecting membrane 211 of the adjustment section 21 is stacked in the axial direction of the branch stent 20, when constructing the branch guidewire, the stacked connecting membrane 211 will easily make it difficult for the branch guidewire to move forward.

[0061] In other embodiments, the reinforcing rib 212 may also be a combination of a conical wavelet 2123 and a flexible reinforcing rib 2124, wherein the wave height h of the conical wavelet 2123 and the wave height H of the supporting wavelet 222 satisfy the following relationship: H / 5≤h≤H / 2. As shown in FIG2b , the reinforcing rib 212 includes a conical wavelet 2123 and four flexible reinforcing ribs 2124, wherein the conical wavelet 2123 is disposed between the flexible reinforcing rib 2124 and the first end 20a, and the flexible reinforcing rib is disposed axially between the conical wavelet 2123 and the supporting wavelet 222 along the branch support, and the four flexible reinforcing ribs are spaced apart circumferentially of the branch support 20 and are evenly spaced, so that the flexible reinforcing ribs 2124 of the branch support 20 are evenly distributed circumferentially of the connecting membrane between the conical wavelet 2123 and the supporting wavelet 222. The arrangement of the flexible reinforcing ribs 2124 may refer to the arrangement of the ridge-type reinforcing ribs formed by sutures. The conical small wave ring 2123 and the flexible reinforcing rib 2124 are combined and arranged, and the flexible reinforcing rib 2124 is arranged between the conical small wave ring 2123 and the supporting wave ring 222. On the one hand, the expansion degree of the connecting membrane at the connecting end of the branch bracket 20 and the main bracket 10 can be guaranteed. On the other hand, the flexible reinforcing rib 2124 is close to the supporting wave ring 222, which makes it easier to drive the supporting section to sink when the branch bracket is subjected to force. At the same time, it prevents the connecting membrane 211 from stacking in the axial direction due to the connecting membrane 211 being too soft to provide support along the axial direction of the branch bracket 20, thereby avoiding difficulty in advancing the branch guide wire.

[0062] In other embodiments, as shown in Figure 7, the frustum-shaped side of the adjustment section 21 can be an arc-shaped transition, and the arc is recessed toward the inner side of the branch bracket 20, so that the reinforcing ribs 212 extending along the connecting membrane 211 of the adjustment section 21 are also recessed toward the inner side of the branch bracket 20. Compared with the case where they bulge toward the outer side of the branch bracket 20, when subjected to the same external force, the reinforcing ribs 212 transition in an arc shape along the connecting membrane 211 and are recessed toward the inner side of the branch bracket 20, which is more conducive to the downward flipping of the adjustment section 21.

[0063] In this embodiment, as shown in FIG8 , one of the reinforcing ribs 212 is a whole structure similar to a breakpoint or a broken section in its extension direction. The reinforcing rib 212 includes a first end 2121 and a second end 2122. The first end 2121 is close to the first end 20a of the branch bracket 20, and the second end 2122 is close to the second end 20b of the branch bracket 20. A gap d1 is provided between the first end 2121 and the first end 20a of the branch bracket 20, and / or a gap d2 is provided between the second end 2122 and the support section 22. d1 and d2 The following conditions are satisfied: 1mm≤d1≤3mm, 1mm≤d2≤3mm, so that the two ends of the reinforcing rib 212 do not extend to the two end edges of the adjusting section 21, and a gap is left beside the two ends of the reinforcing rib 212. When the adjusting section 21 is flipped down into the main cavity, the supporting section 22 sinks into the main cavity along with the adjusting section 21. The adjusting section 21 cooperates with the branch opening 11 to form a micro "cradle-like" structure. The gap d1 and the gap d2 both help the supporting section 22 to slightly translate and shake within the range of the branch opening 11, and can also increase its flexibility and swing range during free swing.

[0064] As shown in FIG9 , a reinforcing rib 212 includes a first section 212a and a second section 212b along its extension direction, and a gap d3 is provided between the first section 212a and the second section 212b, so that a reinforcing rib 212 is divided into two sections at intervals in its extension direction. In this embodiment, the section close to the main frame 10 is the first section 212a, and the section close to the supporting section 22 is the second section 212b, so that the adjustment section 21 can be partially or completely turned down. When only the first section 212a is turned down and the second section 212b is folded relative to the first section 212a, as shown in FIG14 , on the one hand, at this time, the second section 212b still has the possibility of continuing to turn down, and the second section 212b can also be relatively turned down. The support section 22 is folded, as shown in Figure 15, and when only the first section 212a is folded down, the second section 212b provides a certain height to the support section 22, so that the folding down of the reinforcement rib 212 does not necessarily drive the support section 22 to sink into the cavity of the main bracket 10. When the support section 22 tilts relative to the second section 212b, it can be tilted at a larger angle, as shown in Figure 16; on the other hand, as shown in Figures 17-17a and 18-18a, the first section 212a cooperates with the branch port 11 to form a micro "cradle-like" structure, which can make the support part translate and swing in the circumferential direction of the branch bracket 20. Combined with the possibility of the second section 212b to fold down, the flexibility of the branch bracket 20 to swing in all directions can be further increased.

[0065] The coated stent 100 provided in the present application can be an aortic arch stent (as shown in FIG19 ), or a thoracic and abdominal main stent (as shown in FIG20 ), or an abdominal main stent (as shown in FIG21 ), or an iliac bifurcation, etc., where branches need to be set. The branch stent 20 can be set into the structure as described above, so as to be used for aortic arch branches, thoracic and abdominal main branches, abdominal main stents and iliac bifurcation, so as to provide a branch stent 20 that can be flexibly swung, which is convenient for branch alignment, and because the adjustment segment 21 is turned down into the aortic cavity, the support segment 22 is driven to sink, and the support segment 22 can be flexibly swung relative to the circumference of the branch stent 20, so when the coated stent 100 is implanted , it is only necessary that the branch vessel opening corresponds to the branch opening 11 of the main stent 10, so the alignment accuracy of the branch stent 20 and the branch vessel opening is not strictly required; the opening direction (tilt angle) of the second end 20b of the branch stent 20 and the extension length of the branch stent 20 can also be flexibly adjusted according to the angle of the branch artery morphology to be reconstructed. Especially for patients with dissecting aneurysms, when the true lumen is narrow, the branch stent 20 can sink into the main stent 10, or even be flush with the side of the main stent 10, so as to avoid the branch stent being squeezed due to the narrow true lumen space of the aorta, thereby affecting the components of the branch guide wire and the branch blood flow.

[0066] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0067] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present application, and these modifications and improvements fall within the scope of protection of the present application. Therefore, the scope of protection of the present patent application shall be determined by the appended claims.

Claims

1. A covered stent, characterized in that, The covered stent includes a main stent and a branch stent. The main stent includes a branch opening communicating with the branch stent. The branch stent includes an opposite first end and a second end. The first end is connected to the branch opening. The branch stent includes an adjustment section near the first end and a support section near the second end. The adjustment section includes a reinforcing rib so that when the branch stent is stressed, it can drive the support section to sink.

2. The covered stent according to claim 1, characterized in that, The adjustment section further includes a connecting film connecting the branch opening and the support section. The reinforcing rib is arranged on the connecting film, and the reinforcing rib is a flexible reinforcing rib.

3. The covered stent according to claim 2, wherein, The reinforcing rib has a "chain-type" break point structure or break section structure.

4. The covered stent according to claim 1, wherein, The reinforcing rib includes a first section and a second section along its extending direction, and a gap is provided between the first section and the second section.

5. The covered stent according to claim 2, characterized in that, The reinforcing rib includes a sewing thread sewn along the connecting film; Or, the connecting film includes a folding part, and the folding part is thermally pressed and bonded to form the reinforcing rib; Or, the connecting film includes a folding part, the reinforcing rib includes the folding part and a sewing thread, and the sewing thread is sewn along the folding part to form an integral body to form the reinforcing rib.

6. The covered stent according to claim 1, wherein At least two reinforcing ribs are arranged at intervals along the circumferential direction of the branch stent.

7. The covered stent according to claim 1, wherein The branch stent includes a first circumferential support member arranged along the circumferential direction of the branch stent, and the first circumferential support member is arranged at the connection between the adjustment section and the support section.

8. The covered stent according to claim 7, characterized in that, The branch stent further includes a second circumferential support member and a third circumferential support member. The second circumferential support member is arranged at the first end, and the third circumferential support member is arranged at the second end.

9. The covered stent according to claim 8, wherein, Define the diameter of the first circumferential support member as D1, the diameter of the second circumferential support member as D2, and the diameter of the third circumferential support member as D3. D1, D2, and D3 satisfy: D1≤D3<D2; Or, D1, D2, and D3 satisfy: D1≤D3, and 1.5D1≤D2≤3D1.

10. The covered stent according to any one of claims 1-9, characterized in that, The reinforcing rib includes a first end and a second end. The first end is close to the first end, and the second end is close to the second end. A gap is provided between the first end and the first end of the branch stent and / or a gap is provided between the second end and the adjustment section.

11. The covered stent according to claim 1, wherein, The support section includes a support film and a support corrugated ring. The support film covers the support corrugated ring. The reinforcing rib includes a conical small corrugated ring, and the wave height h of the conical small corrugated ring and the wave height H of the support corrugated ring satisfy: H / 5≤h≤H / 2.

12. The covered stent according to claim 1, wherein The reinforcing rib includes a conical small corrugated ring and a flexible reinforcing rib, and the conical small corrugated ring is arranged between the flexible reinforcing rib and the first end.

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