Covered stent

Abstract

This invention provides a covered stent, comprising a main stent having a tubular body, the main stent comprising a proximal segment, a middle segment, and a distal segment along the axial direction, the diameter of the distal segment being smaller than the diameter of the middle segment; the middle segment comprising a first channel and a second channel along the radial direction, the distal segment being connected to the distal opening of the first channel; a first embedded stent is embedded in the second channel, the first embedded stent comprising a first proximal port, a first outer wall, and a first distal port along the axial direction, the first embedded stent having at least the first proximal port fixedly connected to the main stent, the first outer wall and the first distal port being movably connected to the main stent and being movable along the axial direction after connection, the embedded stent being configured to be slidably connected to the connected middle segment at least along the axis, thereby ensuring that the embedded stent has good bending and extension space when bending, avoiding bending due to axial restriction.

Description

Technical Field

[0001] This invention relates to the field of medical device technology, and more particularly to a covered stent. Background Technology

[0002] The iliac arteries include the common iliac artery, external iliac artery, and internal iliac artery. Current techniques for treating iliac artery aneurysms involve endovascular treatment, implanting an iliac artery bifurcation stent and an internal iliac artery covered stent to reconstruct the arterial vessel. Existing iliac artery bifurcation stents typically have two branch channels, one for reconstructing the internal iliac artery and the other for the external iliac artery. These two branch channels must be fully extended within the aneurysm cavity and must not collapse. Generally, arranging the two branch channels side-by-side helps reduce the stent's overall size; however, connecting the two branch channels side-by-side using conventional fixation methods reduces flexibility, making the stent prone to kinking and collapse, especially in cases of tortuous intravascular pathways. Summary of the Invention

[0003] Therefore, it is necessary to provide a new covered stent that can provide multiple branch channels to reconstruct multiple branch vessels while effectively preventing stent occlusion caused by reduced flexibility when multiple branch channels are arranged side by side, resulting in kinking within tortuous vessels.

[0004] A covered stent includes a main stent having a tubular body, the main stent comprising, along an axial direction, a proximal segment, a middle segment, and a distal segment, the diameter of the distal segment being smaller than the diameter of the middle segment; the middle segment includes, along a radial direction, a first channel and a second channel, the distal segment being connected to the distal opening of the first channel; the second channel contains an embedded first stent, the first embedded stent including, along an axial direction, a first proximal port, a first outer wall, and a first distal port, the first proximal port being fixedly connected to the middle segment, and the first outer wall and / or the first distal port being movably connected to the middle segment and, after connection, capable of moving axially relative to the first channel.

[0005] In one embodiment, the distal end of the first embedded support includes an exposed section extending from the distal opening of the second channel, the exposed section being at least partially movably connected to the distal section at a tangential position.

[0006] In one embodiment, the second channel is embedded with a second embedded bracket, which includes a second proximal port, a second outer wall, and a second distal port along the axial direction. The second proximal port is fixedly connected to the main support, and the second outer wall and / or the second distal port are movably connected to the main support and can move axially relative to the second channel after connection.

[0007] In one embodiment, the first outer wall and the second outer wall are at least partially movably connected at their adjacent positions, and after connection, the first embedded bracket and the second embedded bracket can move relative to each other along the axial direction.

[0008] In one embodiment, the active connection includes one or more active connection components, the active connection components being arranged along the axial and / or circumferential direction of the main support.

[0009] In one embodiment, the movable connection assembly includes a fixed member and a movable member, the fixed member having an axially extending track, the movable member being partially sleeved on the track and movable along the track, the fixed member and the movable member being respectively disposed on two supports among the first embedded bracket, the second embedded bracket and the main body bracket.

[0010] In one embodiment, the main support, the first embedded support, and the second embedded support all include a metal frame and a surface coating, and the fixing member and the movable member are disposed on the metal frame and / or the surface coating.

[0011] In one embodiment, the fixing member includes a polymer wire, the moving member includes a polymer ring, and the polymer wire or the polymer ring is stitched or integrally formed on the surface coating.

[0012] In one embodiment, the fastener includes a metal connecting rod, the two ends of which are respectively fixedly connected to the metal frame.

[0013] In one embodiment, the metal connecting rod is disposed on the side wall of the first embedded bracket or the middle section away from the first channel, and is continuously arranged along the axial direction.

[0014] The beneficial effects of the present invention are as follows: Compared with the prior art, the present invention provides a covered stent, including a main stent having a tubular body, the main stent including a proximal section, a middle section and a distal section in sequence along the axial direction, the diameter of the distal section being smaller than the diameter of the middle section; the middle section including a first channel and a second channel in the radial direction, the distal section being connected to the distal opening of the first channel; a first embedded stent is embedded in the second channel, the first embedded stent including a first proximal port, a first outer wall and a first distal port in the axial direction, the first embedded stent being at least fixedly connected to the main stent at the first proximal port, the first outer wall and the first distal port being movably connected to the main stent and being able to move along the axial direction after connection, the embedded stent is configured to be connected to the connected middle section that can slide at least along the axis, thereby ensuring that the embedded stent has good bending and extension space when bending, avoiding bending due to axial restriction. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the overall structure of the film-coated stent in Embodiment 1 of the present invention;

[0016] Figure 2 This is a schematic diagram of the axial cross-sectional structure of the middle section of the film-coated support in Embodiment 1 of the present invention;

[0017] Figure 3 This is a schematic diagram of the radial cross-sectional structure of the middle section of the film-coated support in Embodiment 1 of the present invention;

[0018] Figure 4 This is a schematic diagram of the embedded bracket including the exposed section structure in other embodiments of Embodiment 1 of the present invention;

[0019] Figure 5 This is a schematic diagram of the axial cross-sectional structure of the middle section of the film-coated support in Embodiment 2 of the present invention;

[0020] Figure 6 This is a schematic diagram of the radial cross-sectional structure of the middle section of the film-coated support in Embodiment 2 of the present invention;

[0021] Figure 7 This is a schematic diagram of the radial cross-sectional structure of the middle section of the film-coated support in one embodiment of the second embodiment of the present invention;

[0022] Figure 8 This is a schematic diagram of the axial cross-sectional structure of the film-coated support in one embodiment of the second embodiment of the present invention;

[0023] Figure 9 This is a schematic diagram of the structure of the movable connecting components connecting between the brackets in Embodiment 3 of the present invention;

[0024] Figure 10 This is a schematic diagram of the active connection component structure in Embodiment 3 of the present invention;

[0025] Figure 11 This is a schematic diagram of the structure in Embodiment 3 of the present invention, in which the fixing member is disposed between the wave coil supports;

[0026] Figure 12 This is a schematic diagram of the structure in Embodiment 3 of the present invention, in which the fixing member is disposed between the mesh supports;

[0027] Figure 13 This is a schematic diagram of the structure of the fixing member disposed on the surface coating in Embodiment 3 of the present invention;

[0028] Figure 14 This is a schematic diagram of a metal connecting rod as the fixing component in another embodiment of the present invention.

[0029] Figure 15 This is a schematic diagram of the connection structure between the movable component and the surface coating in Embodiment 3 of the present invention;

[0030] Figure 16This is a schematic diagram of the connection structure between the movable component and the metal frame in Embodiment 3 of the present invention;

[0031] Figure 17 This is a schematic diagram of the keel structure provided in the film-coated support in Embodiment 4 of the present invention. Detailed Implementation

[0032] To better understand the concept of this application, the implementation methods of this application will be described in detail below with reference to the accompanying drawings. The following specific embodiments are only some embodiments of this application and are not intended to limit this application.

[0033] For ease of description, spatial relative terms may be used in the text to describe the relationship of one element or feature relative to another element or feature, as shown in the figure. These relative terms include, for example, "inside," "outside," "middle," "outer," "below," "below," "above," "over," etc. Such spatial relative terms are intended to include different orientations of the device in use or operation, other than those depicted in the figure. For example, if the device in the figure is flipped, an element described as "below other elements or features" or "below other elements or features" would subsequently be oriented as "above other elements or features" or "above other elements or features." Therefore, the example term "below" can include both upper and lower orientations. The device may be otherwise oriented (rotated 90 degrees or in other directions), and the spatial relative descriptors used in the text will be interpreted accordingly.

[0034] Although terms such as first, second, third, etc., may be used in this document to describe multiple elements, components, regions, layers, and / or segments, these elements, components, regions, layers, and / or segments should not be limited by these terms. These terms may be used only to distinguish one element, component, region, layer, or segment from another. Unless the context clearly indicates otherwise, terms such as "first," "second," and other numerical terms used herein do not imply order or sequence. Therefore, the first element, component, region, layer, or segment discussed below may be referred to as the second element, component, region, layer, or segment without departing from the teachings of the exemplary embodiments.

[0035] To more clearly describe the structure of this application, the terms "proximal" and "distal" are used here as conventional terms in the field of interventional medicine. Specifically, "distal" refers to the end of the blood vessel furthest from the heart, and "proximal" refers to the end of the blood vessel closest to the heart; "axial" refers to its length direction, and "radial" refers to the direction perpendicular to the "axial" direction; "upper end" and "lower end" refer to two relatively distant ends, and when one end is defined as "upper end", the other distant end is "lower end".

[0036] Example 1:

[0037] This invention provides a film-coated stent 100, please refer to [link / reference]. Figure 1 The covered stent 100 typically consists of a supporting framework and a covering material. The metal framework 40 can employ a Z-shaped wave or a woven mesh design. The covering material has a certain blood flow isolation capability and is combined with the supporting framework through methods such as pressure heating and suturing to form a complete covered stent 100. In this invention, the covered stent 100 is typically used in the iliac artery and its branches in the human body. However, this does not mean that the covered stent 100 can only be applied to the iliac artery. Other vascular locations in the human body with similar structures and environments may also be suitable for the covered stent 100. The proximal end of the covered stent 100 is generally placed in the common iliac artery or connected to an abdominal aortic stent, and the lumen diameter is generally matched to the diameter of the common iliac artery. In this embodiment, the covered stent 100 includes a main stent 10 with a tubular body. The main stent 10 includes a proximal segment 1, an intermediate segment 2 and a distal segment 3 in sequence from the proximal end to the distal end along the axial length direction. The proximal segment 1 is usually used to provide overall vascular anchoring, anchored in the common iliac artery or abdominal aortic stent, and receives blood. The proximal end of the intermediate segment 2 is connected to the proximal segment 1, and the distal end is connected to the distal segment 3.

[0038] The laminated support 100 described in this application, please refer to [link / reference needed]. Figure 2 and Figure 3The intermediate segment 2 is typically positioned as a blood diversion point. Depending on the blood flow direction, it is spatially divided into a first channel 22 and a second channel 21. The second channel 21 is usually the internal iliac channel, and the first channel 22 is usually the external iliac channel. The internal iliac channel typically uses an internal iliac covered stent to drain some of the blood flowing through the intermediate segment 2 to the internal iliac vessels. The distal segment 3, after the covered stent 100 is implanted and released into the blood vessel, is usually located within the external iliac vessels and is used to drain some of the blood flowing through the intermediate segment 2 to the external iliac vessels. The distal segment 3 has a smaller diameter than the proximal segment 1 and the intermediate segment 2. This design allows the distal segment 3 to be better selected for implantation into the external iliac vessels and to better adapt to the morphology of the external iliac vessels. The distal end of the intermediate segment 2 includes a distal opening, which includes an opening portion for implantation of the internal iliac stent graft and a portion for connection with the proximal end of the distal segment 3. The distal segment 3 is connected to the distal opening and only covers a portion of the distal opening, while communicating with the first channel 22. Thus, the distal opening portion not connected to the distal segment 3 can be used for implantation of the internal iliac stent graft to connect with the second channel 21. In this embodiment, to ensure the stability of the connection between the internal iliac stent and the stent 100 provided in this application after intervention, a first embedded stent 23 is embedded in the second channel 21 of the intermediate segment 2. The embedding of the first embedded stent 23 can better divert the flowing blood in the intermediate segment 2 before it enters the corresponding branch tube. Furthermore, being embedded in the second channel 21 opposite to the internal iliac channel, it can establish a cylindrical or near-cylindrical independent anchoring channel in this channel, thereby ensuring that when the internal iliac stent is intervened at this position, all four sidewalls can abut and anchor against the inner sidewall of the first embedded stent 23, thereby increasing the anchoring performance of the internal iliac stent. In addition, good anchoring performance can also reduce the possibility of blood leakage from the stent 100 at this position.

[0039] In this embodiment, please refer to Figure 3The intermediate section 2 includes a supporting frame and a coating material. The first embedded bracket 23 is located within the cavity of the intermediate section 2 by connecting to the intermediate section 2 of the main bracket 10. It should be understood that when a single bracket is bent, the small and large bending sides of its bending direction will be accompanied by corresponding axial length deformations. Specifically, this typically involves a shortening of the small bending side and a stretching of the large bending side, to naturally form a bracket bending structure that maintains the cavity space. Different brackets use different metal frame 40 structures, different coating materials, or different bracket diameters and shapes, etc. The shortening of the length on the small bend side and the stretching of the length on the large bend side are not exactly the same. If the first embedded stent 23 is fixed in the middle segment 2 in a non-movable manner by suturing, when the middle segment 2 bends in the blood vessel, the bending deformation of the first embedded stent 23 cannot be in its most natural way because the middle segment 2 is fixed. It will be restricted by the middle segment 2, resulting in poor flexibility and difficulty in bending. If it is in a blood vessel segment with a large degree of curvature, the poor bending performance will lead to bending on the small bend side or collapse on the large bend side, thereby causing stent occlusion and affecting blood flow. To ensure that the first embedded stent 23 can be fixed in position relative to the main stent 10, and that its bending is not affected by other stents, the first embedded stent 23 includes a first proximal port 231, a first outer wall 232, and a first distal port 233 along the axial direction. At least the first proximal port 231 of the first embedded stent 23 is fixedly connected to the main stent 10, and the first outer wall 232 and the first distal port 233 are movably connected 24 to the main stent 10 and can move axially after connection. The first proximal port 231 of the first embedded stent 23 is usually connected to the proximal opening of the intermediate segment 2, which is connected to the proximal segment 1 and is used to receive blood flow from the proximal segment 1. The first proximal port 231 of the first embedded stent 23 is the direction of blood entry and is the direction of guidewire insertion when intervening in the internal iliac stent graft. Therefore, its positional fixation and stability need to be guaranteed. Thus, fixing it to the intermediate segment 2 of the main stent 10 can ensure its stability. Here, the movable connection 24 between the first outer wall 232 and the first distal port 233 and the main support 10 ensures that the first embedded support 23 can move relative to the main support 10 in other parts except the first proximal port 231. Thus, when bending occurs, the first embedded support 23 can overcome the influence of the middle section 2 of the main support 10 on its bending shape. At least in the axial direction, the shortening length of the small bend side and the extension length of the large bend side are not restricted and can bend on their own, thereby ensuring the shape of the inner cavity of the first embedded support 23 after bending.Furthermore, in order to enable the first embedded bracket 23 to move relative to the main bracket 10 while avoiding arbitrary movement in the circumferential or radial direction that would cause the shape and position of the first embedded bracket 23 within the intermediate section 2, the movable connection 24 between the first outer wall 232 and the first distal port 233 of the first embedded bracket 23 and the main bracket 10 is a connection that can only move along the axial direction of the main bracket 10. The purpose is to restrict the movement of the first embedded bracket as a whole in the circumferential and radial directions.

[0040] In this embodiment, the movable connection 24 is implemented by setting a movable connection component 240. The movable connection component 240 is configured such that relative displacement in the axial direction can occur between the two supports connected by the movable connection component 240, while radial and circumferential movement is restricted. Only one movable connection component 240 may be provided, located at the first distal port 233 of the first embedded support 23 and connected to the main support 10. This fixes the position of the distal port of the first embedded support 23 relative to the middle section 2 while ensuring that the first embedded support 23 can move axially relative to the middle section 2. In other embodiments, multiple movable connection components 240 may be provided. The multiple movable connection components 240 can be set in the axial and circumferential directions of the first embedded support 23, thereby forming a multi-point position fixation. This effectively improves the stability of the first embedded support 23 relative to the middle section 2 after fixing its relative position other than the axial relative position, preventing its random shaking from affecting the overall stability of the support.

[0041] In one embodiment, the movable connecting component 240 can be arranged along the axial tangential direction when the first embedded stent 23 and the intermediate section 2 are attached. In this way, the adhesion between the first outer wall 232 of the movable connecting component 240 and the intermediate section 2 can be ensured, and the swaying during delivery or blood flushing can be avoided, which would affect the overall stability of the covered stent 100. At the same time, the first embedded stent 23 can still move axially relative to the intermediate section 2.

[0042] In another embodiment, please refer to Figure 3 Multiple movable connection components 240 can be arranged around the first far port 233 of the first embedded bracket 23. This arrangement can fix the first far port 233 of the first embedded bracket 23 relative to the middle section 2 in all positions except for the axial relative position, thereby preventing the first far port 233 from swinging.

[0043] In other embodiments, please refer to Figure 4To minimize the impact of the main support 10 on the first embedded bracket 23 during bending, the axial length of the intermediate section 2 located in the second channel 21 can be set to be less than the axial length of the first embedded bracket 23. This allows the distal end of the first embedded bracket 23 to protrude through the distal opening of the second channel 21 of the intermediate section 2, forming an exposed section 234. When the first embedded bracket 23 bends, the exposed section 234 is essentially unaffected by the main support 10, thus maximizing the bending shape of the first embedded bracket 23. Furthermore, to prevent the exposed section 234 from swaying relative to the main support 10, it can be at least partially connected to the distal section 3 at the tangent position 235 via a movable connecting assembly 240, thereby preventing arbitrary swaying of the exposed section 234 in directions other than the axial direction.

[0044] Example 2:

[0045] In this embodiment, please refer to Figure 5 The first embedded stent 23 and the main stent 10 are largely the same as in Embodiment 1. The difference lies in that, in order to minimize the influence between the first channel 22 and the second channel 21 within the intermediate segment 2, thereby ensuring more stable blood flow to the internal and external iliac vessels, a second embedded stent 25 is embedded within the first channel 22. The first embedded stent 23 and the second embedded stent 25 are arranged side by side within the intermediate segment 2, occupying the lumen of the intermediate segment 2. The purpose of the second embedded stent 25 is to ensure the embedded shape of the external iliac channel portion and to avoid insufficient blood supply to the external iliac vessels due to excessive compression of the external iliac channel caused by the placement of the first embedded stent 23 in the internal iliac channel portion. Therefore, the second embedded stent 25 is provided to support the space of the external iliac channel portion. It should also be understood here that when two stents are placed side by side and bent in the direction of either stent, if the two ends of the two stents are fixed relative to each other, the flexibility of the two stents will be poor. This is because the deformation between the sides of the two stents that are close to each other when they are placed side by side will be mutually restricted. As a result, the large bend side of the stent located on the inner side of the bend is difficult to extend and may twist or collapse on the large bend side. Meanwhile, the small bend side of the stent located on the outer side of the bend is difficult to shorten and may bend or twist on the small bend side. This seriously affects the luminal shape of the two stents after bending, thereby affecting the blood flow.

[0046] To ensure that the second embedded bracket 25 is also unaffected by the main bracket 10 when bending, please refer to... Figure 5 and Figure 6The second embedded stent 25 includes a second proximal port 251, a second outer wall 252, and a second distal port 253 along the axial direction. At least the second proximal port 251 of the second embedded stent 25 is fixedly connected to the main stent 10. The second outer wall 252 and the second distal port 253 are movably connected to the main stent 10 and can move axially after connection. The second proximal port 251 of the second embedded stent 25 is usually connected to the proximal opening of the intermediate section 2. The second proximal port 251 of the second embedded stent 25 is also in the direction of blood entry. Therefore, the fixation and stability of its position are necessary to ensure stable blood flow and need to be guaranteed. Therefore, fixing it to the intermediate section 2 of the main stent 10 can ensure its stability. Here, the movable connection 24 between the second outer wall 252 and the second distal port 253 and the main support 10 ensures that the second embedded support 25 can move relative to the main support 10 in other parts except for the second proximal port 251. Thus, when bending occurs, the first embedded support 23 can overcome the influence of the middle section 2 of the main support 10 on its bending shape. At least in the axial direction, the shortening length of the small bending side and the extension length of the large bending side are not restricted by the main support 10 and can bend on their own, thereby ensuring the shape of the inner cavity of the second embedded support 25 after bending.

[0047] In this embodiment, please refer to Figure 7 To further ensure that the bending of the first embedded bracket 23 and the second embedded bracket 25 does not affect each other when they are arranged side by side, the adjacent positions 26 of the first outer wall 232 of the first embedded bracket 23 and the second outer wall 252 of the second embedded bracket 25 are at least partially movablely connected by a 24. After connection, the first embedded bracket 23 and the second embedded bracket 25 can move relative to each other axially. Here, since the first embedded bracket 23 and the second embedded bracket 25, except for the first proximal port 231 and the second proximal port 251 which are relatively fixed, are all connected by a movable connection 24 that allows axial movement, when the first embedded bracket 23 and the second embedded bracket 25 are bent toward either side of the inner cavity bracket, the side that is close to and tangent to each other can move axially. Since the first embedded stent 23 and the second embedded stent 25 are movable, their bending deformation is not restricted at least on this side. Furthermore, since the movable connection 24 between the first embedded stent 23 and the second embedded stent 25 and the main stent 10 can also achieve axial movement, the first embedded stent 23 and the second embedded stent 25 arranged side by side are actually in a state where only the first proximal port 231 and the second proximal port 251 are fixed, but other positions can move axially. Therefore, when the first embedded stent 23 and the second embedded stent 25 bend in the blood vessel following the main stent 10, their own bending deformation is not affected by the deformation of the main stent 10 or is only slightly affected, thereby maintaining a good bending shape and thus maintaining the space of the inner lumen after bending.

[0048] In one embodiment, see Figure 8 The second embedded bracket 25 and the distal segment 3 can be connected in a one-piece molding manner. Here, one-piece connection means that the metal skeleton of the second embedded bracket 25 and the distal segment 3 are connected together at least by continuous individual coatings, and not by stitching or bonding. When the second embedded bracket 25 and the distal segment 3 are connected in a one-piece molding manner, the second embedded bracket 25 and the distal segment 3 are connected at the distal opening of the first channel 22 only by a movable connection 24, thereby avoiding the distal end of the second embedded bracket 25 being fixed, and ensuring that the second embedded bracket 25 can achieve axial displacement when bending.

[0049] In this embodiment, the proximal segment 1, intermediate segment 2, and distal segment 3 of the covered stent 100 have a metal skeleton 40 with a coiled stent 41 structure, while the first embedded stent 23 and the second embedded stent 25 have a metal skeleton 40 with a woven or cut mesh stent 42 structure. The main stent 10 with the coiled stent 41 structure has good bending flexibility, which is beneficial to the overall coverage of the covered stent 100 in the blood vessel and its compliance after release. Since the first embedded stent 23 and the second embedded stent 25 are located in the lumen of the intermediate segment 2, they themselves are designed with... The purpose of this arrangement is to establish a better-shaped internal iliac canal and external iliac canal. Here, the metal skeleton 40 with the mesh support 42 structure is beneficial to maintaining the internal structure of the first embedded support 23 and the second embedded support 25. However, compared with the metal skeleton 40 with the wave-loop support 41 structure, it has lower flexibility. Therefore, the purpose of setting the first embedded support 23 and the second embedded support 25 to be able to slide axially relative to each other when bending is also to avoid further reducing the flexibility of the first embedded support 23 and the second embedded support 25 when bending.

[0050] Example 3:

[0051] In this embodiment, please refer to Figure 9 and Figure 10 The structure of the embedded bracket and the main bracket 10 is largely the same as that in Embodiment 1 and Embodiment 2. The difference is that the movable connection 24 between the first embedded bracket 23, the second embedded bracket 25 and the main bracket 10 is realized by the movable connection assembly 240. The movable connection assembly 240 includes a fixing member 241 and a movable member 242. The fixing member 241 and the movable member 242 are respectively disposed between any two of the first embedded bracket 23, the second embedded bracket 25 and the main bracket 10. The fixing member 241 is fixedly disposed on the bracket and forms a track 2412 that allows the movable member 242 to move axially. The movable member 242 is partially disposed on the track 2412 of the fixing member 241 by sleeve and moves along the track 2412. The movable member 242 is fixedly connected to other brackets different from the fixing member 241.

[0052] In this embodiment, please refer to Figure 10 The fastener 241 has two axially oriented fixing points 2411 at both ends. The fixing points 2411 are fixedly connected to the support. A track 2412 is located between the fixing points 2411. The fastener 241 can be a long polymer thread, which can be a rigid or flexible material. It can be made of the same material as the sutures or coverings of the main support 10, the first embedded support 23, or the second embedded support 25, such as PET or PTFE. In this embodiment, to better ensure the flexibility of the first embedded support 23 and the second embedded support 25, and the long-term patency of blood flow in their lumens, the first embedded support 23 and the second embedded support 25 are typically covered with a PTFE surface film 50, while the surface film 50 of the main support 10 is typically covered with a PET film. The fastener 241 can be connected to adjacent metal skeletons 40 by stitching, with the two fixing points 2411 stitched between two axially adjacent metal skeletons 40. See here for further details. Figure 11 If two adjacent metal frames 40 adopt a wave ring bracket 41, then the two fixing points 2411 of the fixing member 241 are respectively connected to the crests and / or troughs of the two adjacent wave ring brackets 41 that are close to each other in the axial direction. The bending structure of the crests and troughs of the wave ring bracket 41 can prevent the fixing member 241 from sliding on the wave rod at will, thereby ensuring the stability of the relative position of the fixing member 241.

[0053] In one embodiment, see Figure 12 When two adjacent metal frames 40 are mesh supports 42, since the mesh supports 42 have a rectangular or rhomboid mesh structure, the two fixing points 2411 can be connected to two opposite corners in the axial direction within a single mesh. In this way, fixing at the corners can also prevent the fixing member 241 from sliding on the wave rod at will, thereby ensuring the stability of the relative position of the fixing member 241.

[0054] In other embodiments, please refer to Figure 13The fastener 241 can also be set on the surface film 50 of the intermediate section 2. By connecting with the surface film 50, the two fixing points 2411 of the fastener 241 do not need to consider the connection stability of the fixing position. When the fastener 241 is set on the surface film 50 of PET material, the two points can be connected by the direction of stitching. When the fastener 241 is set on the surface film 50 of PTFE material, the fastener 241 can be integrally formed on the surface of the surface film 50 during the molding process of the PTFE material surface film 50. Furthermore, PT... The surface coating 50 of the FE material typically includes an inner surface coating 50 and an outer surface coating 50. In this application, the first embedded bracket 23 and the second embedded bracket 25 are coated with PTFE material for long-term patency considerations. When the fastener 241 is disposed on the surface coating 50 of the first embedded bracket 23 and the second embedded bracket 25, it is integrally formed on the outer surface coating 50. In this way, the inner cavity of the first embedded bracket 23 and the second embedded bracket 25 is not affected by the setting of the fastener 241, thereby ensuring the long-term patency of the inner cavity.

[0055] In another embodiment, please refer to Figure 14 Alternatively, the fixing member 241 can be set by means of a metal connecting rod. In this way, the fixing points 2411 at both ends of the metal connecting rod can be formed by weaving together the metal skeleton 40 of the main support 10, the first embedded support 23 or the second embedded support 25. During the weaving process, the fixing member 241 is woven in the axial direction. Alternatively, the fixing points 2411 at both ends of the metal connecting rod can be connected to two metal skeletons 40 with adjacent axes by welding. The fixing points 2411 are formed by welding, so that the fixing member 241 can be formed at any position of the metal skeleton 40. This makes the selection of the relative position of the movable connection 24 more flexible and can be set in a position that is more conducive to bending flexibility. At the same time, the stability of the fixing member 241 after fixing can also be improved.

[0056] In this embodiment, please refer to Figure 15 and Figure 16The movable component 242 is partially fitted onto the track 2412 of the fixed component 241. The movable component 242 is at least partially fixed to a bracket different from the corresponding fixed component 241. Similarly, the movable component 242 can be a polymer ring structure formed of polymer material. The polymer ring can be a rigid or soft material, and can be made of the same material as the stitching or coating of the main bracket 10, the first embedded bracket 23, or the second embedded bracket 25, such as PET or PTFE. The polymer ring can be fixed to the metal skeleton 40 or the surface coating 50. When fixed to the metal skeleton 40, it is fixed by stitching; when fixed to the surface coating 50, the polymer ring can be attached to the surface coating 50 by stitching or integral molding with the surface coating 50.

[0057] Example 4:

[0058] In this embodiment, please refer to Figure 17 The structure of the embedded stent and the main stent 10 is largely the same as that in Embodiments 1 to 3. The difference is that, in order to ensure the overall shape of the inner lumen of the embedded stent when the covered stent 100 bends in the blood vessel, while avoiding excessive bending of the middle segment 2 toward the internal iliac canal, which would cause the distal stent to block or occlude the internal iliac canal, a structure similar to the keel 60 is provided in the internal iliac canal of the middle segment 2 of the covered stent 100. This restricts the bending of the middle segment 2 of the covered stent 100 toward the internal iliac canal, thereby avoiding excessive bending toward the internal iliac canal as much as possible. Here, when the support has a keel 60 on one side, when the side with the keel 60 is bent as a small bend, it is difficult to bend in that direction because the keel 60 cannot be compressed axially. In this embodiment, the keel 60 structure can be formed by continuously axially setting the fixing member 241, which is set as a metal connecting rod, on the internal iliac channel portion. Specifically, the fixing member 241 can be set as a single piece with a continuous axial length and set on the side wall of the first embedded support 23 or the middle section 2 away from the first channel 22, extending to the entire length of the middle section 2. With this setting, the movable member 242 only needs to be set in multiple directions along the direction of the fixing member 241 on adjacent corresponding supports to realize the axial movable connection 24 between the first embedded support 23 and the main support 10. At the same time, the fixing member 241 can function as the keel 60 in this lateral direction.

[0059] In other embodiments, the fixing member 241, which is set as a metal connecting rod, can also be provided in multiple ways along the axial direction of the side wall away from the first channel 22 of the first embedded bracket 23 or the middle section 2. The multiple metal connecting rods are continuously arranged in the same straight line in the axial direction. Thus, while the first embedded bracket 23 and the middle section 2 can be movably connected 24 in the axial direction, when the multiple metal connecting rods are bent, the axial ends of the adjacent metal connecting rods abut against each other because they are arranged in the same straight line direction. After abutting, they cannot continue to move or be squeezed, thus forming a keel structure with intervals. With such metal connecting rods, a certain gap can be set between adjacent metal connecting rods. The gap is no more than 0.5mm, so that the middle section 2 of the covered bracket 100 can bend slightly in the internal iliac channel part away from the external iliac channel part, while avoiding excessive bending, thereby enhancing the flexibility of the internal iliac channel part.

[0060] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A covered stent, characterized in that, The device includes a main support with a tubular body, the main support comprising a proximal section, a middle section and a distal section in sequence along the axial direction, the diameter of the distal section being smaller than the diameter of the middle section; the middle section comprising a first channel and a second channel in the radial direction, the distal section being connected to the distal opening of the first channel; the second channel contains a first embedded support, the first embedded support comprising a first proximal port, a first outer wall and a first distal port in the axial direction, the first proximal port being fixedly connected to the middle section, the first outer wall and / or the first distal port being movably connected to the middle section and being able to move axially relative to the first channel after connection.

2. The covered stent according to claim 1, characterized in that, The distal end of the first embedded support includes an exposed section that extends from the distal opening of the second channel, and the exposed section is at least partially movably connected to the distal section at a tangential position.

3. The covered stent according to claim 1, characterized in that, The second channel is embedded with a second embedded bracket. The second embedded bracket includes a second proximal port, a second outer wall and a second distal port along the axial direction. The second proximal port is fixedly connected to the main bracket. The second outer wall and / or the second distal port are movably connected to the main bracket and can move axially relative to the second channel after connection.

4. The covered stent according to claim 3, characterized in that, The first outer wall and the second outer wall are at least partially movably connected at their adjacent positions, and after connection, the first embedded bracket and the second embedded bracket can move relative to each other along the axial direction.

5. The covered stent according to any one of claims 1 to 4, characterized in that, The movable connection includes movable connection components, and there are one or more movable connection components, which are arranged along the axial and / or circumferential direction of the main support.

6. The covered stent according to claim 5, characterized in that, The movable connection assembly includes a fixed member and a movable member. The fixed member has a track extending axially, and the movable member is partially sleeved on the track and can move along the track. The fixed member and the movable member are respectively disposed on two supports among the first embedded bracket, the second embedded bracket, and the main body bracket.

7. The covered stent according to claim 6, characterized in that, The main support, the first embedded support, and the second embedded support all include a metal frame and a surface coating, and the fixing member and the movable member are disposed on the metal frame and / or the surface coating.

8. The covered stent according to claim 7, characterized in that, The fixing component includes polymer wires, and the moving component includes polymer rings. The polymer wires or polymer rings are stitched or integrally formed onto the surface coating.

9. The covered stent according to claim 7, characterized in that, The fastener includes a metal connecting rod, the two ends of which are fixedly connected to the metal frame.

10. The covered stent according to claim 9, characterized in that, The metal connecting rod is disposed on the side wall of the first embedded bracket or the middle section away from the first channel, and is continuously arranged along the axial direction.

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