Covered stent, covered stent system and manufacturing method of covered stent

Abstract

The application discloses a covered stent, a covered stent system and a manufacturing method of the covered stent. The covered stent comprises a main stent, an anchoring branch and a connecting membrane sleeve. The anchoring branch comprises an inner tube segment and an outer tube segment. A connecting portion in a circumferential direction is formed at a connecting position of the inner tube segment and the outer tube segment. A first port portion of the connecting membrane sleeve is connected with the anchoring branch, and a second port portion is connected with the main stent at an edge of a window hole. The inner tube segment and the outer tube segment are respectively located at an inner side and an outer side of a skirt of the connecting membrane sleeve. The anchoring branch is movable in a radial direction of the main stent to approach or move away from a central axis of the main stent. The anchoring branch has at least an outermost protruding position and an innermost recessed position. When the anchoring branch is at the outermost protruding position, the connecting portion is located above a surface of the window hole, and the connecting membrane sleeve is in a convex boss shape. When the anchoring branch is at the innermost recessed position, the connecting portion is located below the surface of the window hole, and the connecting membrane sleeve is in an inner recess shape. The application aims to reduce the difficulty and risk of surgery under the premise of ensuring anchoring strength.

Description

Technical Field

[0001] This invention belongs to the field of medical device technology, specifically relating to a covered stent, a covered stent system, and a method for manufacturing the covered stent. Background Technology

[0002] Aortic aneurysm and aortic dissection are serious diseases that threaten human life. If left untreated, the aortic aneurysm and dissection will continue to expand and eventually rupture, causing serious complications and death.

[0003] Traditional open surgery for aortic aneurysms and aortic dissections is highly invasive, has a high mortality rate, long operation time, high postoperative complication rate, and is technically challenging. In contrast, interventional endovascular treatment, with its minimally invasive nature, fewer postoperative complications, shorter operation time, and lower technical difficulty, has gradually become the primary method for treating aortic aneurysms and aortic dissections. However, aortic arch aneurysms and aortic dissections involving the openings of the brachiocephalic artery, left common carotid artery, and left subclavian artery remain a significant challenge in this treatment technique. To ensure the stent is firmly fixed within the aorta and to prevent blood leakage from the proximal or distal end of the stent, current aortic stents require a relatively long anchoring zone at either end. This long anchoring zone is typically convex outwards on the outside of the main stent or convex inwards on the inside of the main stent. The drawbacks of this overall outward and inward convexity are as follows: when the branch is convex outwards, the longer anchoring zone increases the risk of the branch edge rubbing against the vessel. This "scratching" risk of the stent can lead to a series of core complications, such as thrombosis, restenosis, and local vascular reactions. Furthermore, if the main stent is misplaced, and the excessively long external branch is misaligned with the supra-aortic branch, the likelihood of bending and torsion is higher, affecting the patency of branch blood flow. When the branch is designed to convex inward, the medial branch becomes too long, and its end is suspended in the high-speed aortic blood flow, which can easily form a continuous vortex zone and increase the risk of thrombosis. At the same time, the long branch swings periodically under the impact of blood flow, which can easily lead to metal fatigue and pose a risk of stent breakage. In addition, the excessively long medial branch is prone to squeezing towards the aortic wall after release, which may compress the opening of adjacent branches. The adverse effects of these defects increase the difficulty and risk of the operation. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a covered stent, a covered stent system, and a method for manufacturing a covered stent, aiming to reduce surgical difficulty and risks while ensuring the anchoring strength of the covered stent.

[0005] To achieve this objective, the present invention adopts the following technical solution:

[0006] This invention provides a membrane-covered support, comprising a tubular main support and a tubular anchoring branch, and a connecting membrane sleeve connecting the main support and the anchoring branch. The main support has a window opening on its tubular wall. The anchoring branch is positioned within the area of ​​the window opening, and when the central axis of the anchoring branch is perpendicular to the central axis of the main support, the projected outline of the anchoring branch in the plane containing the window opening is within the annulus of the window opening, forming an annular region between the projected outline and the window opening. The surface area of ​​the connecting membrane sleeve is larger than the area of ​​the annular region. The anchoring branch includes an axially connected inner tube segment and an outer tube segment, with the connection point between the inner tube segment and the outer tube segment forming a circumferential connection. The first end portion of the connecting membrane sleeve is connected to the anchoring branch. The second port, opposite to the first port, is connected to the main support at the edge of the window. The connecting membrane sleeve includes a skirt, with the inner tube segment and the outer tube segment located on the inner and outer sides of the skirt, respectively. The anchoring branch is at least radially movable along the main support to approach or move away from the central axis of the main support. The anchoring branch has at least an outermost protruding position farthest from the central axis of the main support and an innermost recessed position closest to the central axis of the main support. When in the outermost protruding position, the circumferential connection is located above the surface where the window is located, and the connecting membrane sleeve is in the shape of an outwardly convex boss. When in the innermost recessed position, the circumferential connection is located below the surface where the window is located, and the connecting membrane sleeve is in the shape of an inwardly concave ...

[0007] In one embodiment, the anchoring branch includes a branch skeleton and a branch covering film. The branch covering film includes a fixing film that is fixed relative to the branch skeleton. The connecting film sleeve also includes a tube sleeve connected to the skirt sleeve. After the connecting film sleeve is fitted onto the anchoring branch, the tube sleeve is fixedly connected to the fixing film.

[0008] In one embodiment, the anchoring branch includes a branch skeleton and a branch covering film. The branch covering film includes a fixed film that is fixed relative to the branch skeleton and a skirt film that surrounds the outer periphery of the branch skeleton and is movable relative to the branch skeleton. The skirt film extends from the circumferential connection point toward the side away from the outer tube segment and gradually away from the central axis of the anchoring branch. The connecting film sleeve includes only the skirt sleeve. The first port portion and the second port portion are respectively located at the two ends of the skirt sleeve. The first port portion of the skirt sleeve is fixedly connected only to the skirt film.

[0009] In one embodiment, the fixing membrane includes an inner branch membrane and an outer branch membrane respectively disposed on the inner and outer walls of the branch skeleton, the branch skeleton being placed between the inner branch membrane and the outer branch membrane, and the skirt membrane being connected to the outer branch membrane.

[0010] In one embodiment, the branch outer membrane and the skirt membrane are integrally formed.

[0011] In one embodiment, the inner branch membrane, the outer branch membrane, and the skirt membrane are integrally formed. The branch skeleton is sleeved on the tubular covering membrane, and the side of the tubular covering membrane near the outer tube segment extends from the outer end of the outer tube segment. The extended portion is folded towards the side where the inner tube segment is located and then fixed to the branch skeleton to form the outer branch membrane on the inner tube segment. The remaining portion after folding forms the skirt membrane that can move relative to the branch skeleton.

[0012] In one embodiment, the skirt includes a connecting membrane layer, which is fitted onto the outer periphery of the anchoring branch, with its first port located above or below the skirt edge membrane and fixedly connected to the skirt edge membrane; or,

[0013] The skirt cover includes at least two connecting membrane layers, all of which are sleeved on the outer periphery of the anchoring branch. The skirt edge membrane is located above or below all of the connecting membrane layers and is fixedly connected to the connecting membrane layers, or the skirt edge membrane is located between two of the connecting membrane layers and is fixedly connected to the connecting membrane layers.

[0014] In one embodiment, the skirt cover includes an annular region near the circumferential connection, wherein at least a portion of the film thickness within the annular region is greater than the film thickness of other regions of the skirt cover.

[0015] In one embodiment, the skirt membrane includes a plurality of covering sheets arranged sequentially around the outer periphery of the anchoring branch.

[0016] In one embodiment, the length of the anchoring branch is between 7 mm and 10 mm; and / or, the length of the inner pipe section is greater than the length of the outer pipe section.

[0017] In one embodiment, the anchoring branch is eccentrically positioned along the axial direction of the main support within the window area, such that the anchoring branch is closer to the far end of the window.

[0018] In one embodiment, a support ring is fixed at the edge contour of the window, and the coating bracket further includes a first developing element disposed on the support ring, wherein the first developing element is only partially disposed on the support ring.

[0019] In one embodiment, a second developing element is further included. The second developing element is fixed to the main support and is located axially opposite to the proximal end of the window. The film-coating support also includes a first keel, which is fixed to the main support and extends along the length of the main support. The first keel is located at the distal end of the window. The second developing element is axially opposite to the first keel.

[0020] In one embodiment, a bare bracket is further included, which is connected to one end of the main support. The bare bracket has a membrane covering the wave loop along the path of the wave loop. The portion of the bare bracket near the main support extends into the main support and is fixed relative to the main support.

[0021] In one embodiment, a branch support is further included that is detachably connected to the anchoring branch. The branch support is nested within the anchoring branch and anchored to it. The branch support includes an outwardly expanding section near its proximal end. The outer diameter of the outwardly expanding section gradually increases from its distal end to its proximal end. The maximum diameter of the outwardly expanding section is greater than the inner diameter of the anchoring branch. When anchored to the anchoring branch, the outwardly expanding section extends from the end of the inner tube section of the anchoring branch.

[0022] The present invention also provides a covered stent system, the covered stent system including the covered stent and the conveying device described above, the conveying device including a semi-binding structure, the semi-binding structure releasably binding the covered stent so that the covered stent is radially compressed or released from binding.

[0023] The present invention also provides a method for manufacturing a covered scaffold, comprising the following steps:

[0024] S1. Fabricate the main support frame; wherein, the main support frame has window holes on its tube wall;

[0025] S2. Fabricate anchoring branches; wherein the fabricated anchoring branches include an inner pipe section and an outer pipe section that are axially connected, and the connection between the inner pipe section and the outer pipe section forms a circumferential connection.

[0026] S3. Place the anchoring branch on the side of the main support and provide a connecting membrane sleeve including a skirt. Connect the first port of the connecting membrane sleeve to the anchoring branch, and connect the second port opposite to the first port to the main support at the edge of the window hole, such that the inner tube segment and the outer tube segment are located on the inner and outer sides of the skirt sleeve, respectively. When the central axis of the anchoring branch is perpendicular to the central axis of the main support, the projection outline of the anchoring branch in the plane where the window hole is located is within the ring of the window hole, and an annular region is formed between the projection outline and the window hole. The surface area of ​​the connecting membrane sleeve is larger than the area of ​​the annular region. The order of steps S1 and S2 can be interchanged.

[0027] In one embodiment, the anchoring branch fabricated in step S2 includes a branch skeleton and a branch covering film. The branch covering film includes a fixing film fixed relative to the branch skeleton. The connecting film sleeve also includes a tube sleeve connected to the skirt sleeve. After the connecting film sleeve is fitted onto the anchoring branch, the tube sleeve is fixedly connected to the fixing film; or...

[0028] The anchoring branch manufactured in step S2 includes a branch skeleton and a branch covering. The branch covering includes a fixed membrane that is fixed relative to the branch skeleton and a skirt membrane that surrounds the outer periphery of the branch skeleton and can move relative to the branch skeleton. The skirt membrane extends from the circumferential connection point toward the side away from the outer tube section and gradually away from the central axis of the anchoring branch. The connecting membrane sleeve only includes the skirt sleeve. The first port portion and the second port portion are respectively located at the two ends of the skirt sleeve. The first port portion of the skirt sleeve is fixedly connected only to the skirt membrane.

[0029] In one embodiment, when the branch coating includes a fixing film and a skirt film, step S2, which involves creating the anchoring branch, specifically includes:

[0030] A branch liner is provided, on which a branch inner membrane, a branch skeleton, and a branch outer membrane are sequentially arranged from the inside to the outside. A skirt membrane is provided such that it surrounds the outer periphery of the branch skeleton, thereby fixing the branch inner membrane, branch skeleton, and branch outer membrane relatively. Simultaneously, the connecting section of the skirt membrane is connected to the branch outer membrane; or...

[0031] A branch liner is provided, on which a branch inner membrane and a branch skeleton are sequentially disposed from the inside out; an integral connecting membrane is provided, the integral connecting membrane being disposed on the outer periphery of the branch skeleton, and a portion of the integral connecting membrane being fixed relative to the branch inner membrane and the branch skeleton, the remaining portion of the integral connecting membrane forming a skirt membrane movable relative to the branch skeleton; or,

[0032] A branch liner is provided, and a tubular film is covered on the branch liner. The branch skeleton is fitted onto the branch liner with the tubular film, and the side of the tubular film near the outer tube segment extends from the outer end of the outer tube segment. Then, the extended part is folded towards the side where the inner tube segment is located and fixed to the branch skeleton to form the branch outer film on the inner tube segment. The remaining part after folding forms the skirt film that can move relative to the branch skeleton.

[0033] The covered stent, covered stent system, and method for manufacturing the covered stent of this invention feature an anchoring branch with inner and outer segments. This design ensures sufficient anchoring length while reducing both external and internal bulge heights, avoiding the adverse effects of entirely external or internal branch placement. The shorter internal height prevents encroachment on the main stent's lumen, ensuring hemodynamics. The limited range of motion at the end of the inner segment reduces the risk of stent breakage and prevents compression of adjacent branch openings. The shorter external height prevents branch stents from rubbing against blood vessels. More importantly, the anchoring branch can move freely and flexibly to match different vascular anatomy, providing a certain margin of error for the release of both the anchoring branch and the main stent, significantly reducing surgical difficulty and risk. Furthermore, the design of this application allows full utilization of the conical space at the root of the branch during anchoring, creating an effective anchoring length at that location, which greatly reduces the height of both internal and external bulges. Attached Figure Description

[0034] The above and other objects, features, and advantages of the present invention will become clearer through a more detailed description of the preferred embodiments illustrated in the accompanying drawings. The same reference numerals denote the same parts throughout the drawings, and the drawings are not intentionally drawn to scale with actual dimensions; the focus is on illustrating the gist of this application.

[0035] Figure 1 This is a schematic diagram of the structure of an exemplary covered stent of the present invention; wherein, Figure 1 The middle anchoring branch is in the outermost protruding position;

[0036] Figure 2 for Figure 1 A schematic diagram of the three-dimensional structure;

[0037] Figure 3 This is a schematic diagram of the structure of an exemplary covered stent of the present invention; wherein, Figure 2 The middle anchoring branch is located in the innermost concave position;

[0038] Figure 4 for Figure 3 A schematic diagram of the three-dimensional structure;

[0039] Figure 5 This is a top view of an exemplary covered stent of the present invention;

[0040] Figure 6 This is a schematic diagram of a structure for connecting a membrane sleeve and an anchoring branch in an exemplary membrane-covered stent of the present invention, as well as a schematic diagram of the connection structure between the two;

[0041] Figure 7 This is a schematic diagram of another structure for connecting the membrane sleeve and the anchoring branch in an exemplary membrane-covered stent of the present invention, as well as a schematic diagram of the connection structure between the two;

[0042] Figure 8 This is a schematic diagram of another anchoring branch in an exemplary covered stent of the present invention;

[0043] Figure 9 This is a schematic diagram of another anchoring branch in an exemplary covered stent of the present invention;

[0044] Figure 10 This is a schematic diagram of another structure for connecting the membrane sleeve and the anchoring branch in an exemplary membrane-covered stent of the present invention, as well as a schematic diagram of the connection structure between the two;

[0045] Figure 11 This is a schematic diagram of the integrally formed inner branch membrane, outer branch membrane, and skirt membrane on the anchoring branch in an exemplary film-coated stent of the present invention.

[0046] Figure 12 for Figure 11 An enlarged diagram of part A in the diagram;

[0047] Figure 13 This is a schematic diagram of the structure of the film-coated support structure of the present invention after the connection of the connecting film sleeve and the anchoring branch with the skirt film.

[0048] Figure 14 for Figure 1 An enlarged schematic diagram of part B in the diagram;

[0049] Figure 15 This is a schematic diagram of the structure of the anchoring branch and the branch support in the exemplary film-coated stent of the present invention before connection;

[0050] Figure 16 This is a schematic diagram of the structure of the anchoring branch of the scaffold and the branch support after connection, which is an exemplary embodiment of the present invention.

[0051] Figures 17-20 This is a schematic diagram illustrating the structure of the anchoring branch and the branched stent of the scaffold in different tissue morphologies, which is an exemplary embodiment of the present invention.

[0052] Figure label:

[0053] 100-layer laminated support;

[0054] Main support frame 10;

[0055] Anchoring branch 20, inner tube section 21, outer tube section 22, circumferential connection a, branch skeleton 20a, first branch wave ring 20a1, second branch wave ring 20a2, branch covering membrane 20b, fixing membrane 20b1, branch inner membrane 20b11, branch outer membrane 20b12, skirt membrane 20b2, tubular covering membrane 20c;

[0056] Connecting membrane sleeve 30, skirt sleeve 31, tube sleeve 32, first port portion 30a, and second port portion 30b;

[0057] Support ring 40;

[0058] First developing piece 50;

[0059] Second developing piece 60;

[0060] First keel 70, steel sleeve 71;

[0061] Bare stent 80, encapsulated 81;

[0062] Window area 90;

[0063] Branch bracket 200. Detailed Implementation

[0064] To facilitate understanding of the present invention, a more comprehensive description will be given below with reference to the accompanying drawings.

[0065] It should be noted that when a component is considered to be "connected" to another component, it can be directly connected to and integrated with the other component, or there may be an intervening component present. The terms "mounted," "one end," "the other end," and similar expressions used in this document are for illustrative purposes only.

[0066] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0067] In this application, it is defined that after a covered stent is implanted into a blood vessel, the end from which blood flows in is the "proximal end" and the end from which blood flows out is the "distal end", that is, blood flows from the proximal end of the covered stent to the distal end of the covered stent.

[0068] Please see Figures 1-5This invention provides an exemplarily provided covered stent 100, which includes a tubular main stent 10, a tubular anchoring branch 20, and a connecting membrane sleeve 30 connecting the main stent 10 and the anchoring branch 20. The main stent 10 has a main lumen through which blood flows, and the anchoring branch 20 has a branch lumen through which blood flows. The anchoring branch 20 is located on the side of the main stent 10, and the main stent 10 and the anchoring branch 20 are connected by the connecting membrane sleeve 30. The main lumen of the connected main stent 10 communicates with the branch lumen of the anchoring branch 20. The anchoring branch 20 is used to engage with the implanted branch stent 200 to anchor the branch stent 200 (see reference). Figure 15 and Figure 16 This enables the reconstruction of organizational branches. According to the aforementioned definition, in... Figure 1 In the covered stent 100 shown, the blood flow direction is from... Figure 1 The left end of the main support 10 flows into ( Figure 1 The arrows in the diagram indicate the direction of blood flow. If the blood flows out from the right end, then the left side is the proximal end and the right side is the distal end. At the same time, the blood flowing into the main stent 10 flows in from the distal end of the inner tube segment 21 of the anchoring branch 20 (i.e., the port away from the outer tube segment 22) and flows out from the distal end of the outer tube segment 22 of the anchoring branch 20 (i.e., the port away from the inner tube segment 21). Thus, the inner tube segment 21 is on the proximal side and the outer tube segment 22 is on the distal side.

[0069] Continue reading Figures 1-5 The main support 10 has a window (not shown) on its tube wall. The window is a through hole penetrating the side wall of the main support 10. The shape of the window can be a regular shape such as a circle, ellipse, or quadrilateral, or an irregular shape. The shape of the window is not limited. In a preferred embodiment, the window is an ellipse with a circumferential dimension smaller than its axial dimension. Anchoring branches 20 are disposed in the area where the window is located. When the central axis yy of the anchoring branch 20 is perpendicular to the central axis xx of the main support 10, the projected outline of the anchoring branch 20 in the plane where the window is located is within the annulus of the window, and an annular region S is formed between the projected outline and the window (see reference). Figure 5 The surface area of ​​the connecting membrane sleeve 30 is greater than the area of ​​the annular region S, resulting in redundant space in the connecting membrane sleeve 30 compared to the annular region S, allowing for movement of the anchoring branch 20 connected to it. The quantitative indicator for "the surface area of ​​the connecting membrane sleeve 30 is greater than the area of ​​the annular region S" in this invention can be defined as follows: when the central axis yy of the anchoring branch 20 is perpendicular to the central axis xx of the main support 10, and the anchoring branch 20 is in its outermost convex or innermost concave position, taking the central axis yy passing through the anchoring branch 20 as a sectional plane, the distance between the projected contour in the sectional plane and the window hole is less than the length of the connecting membrane sleeve 30 in the sectional plane.

[0070] The anchoring branch 20 of the present invention is movable. Therefore, the phrase "the anchoring branch 20 is arranged in the area where the window is located" in the present invention means that the connection point (i.e., the circumferential connection point a below) between the anchoring branch 20 and the connecting film sleeve 30 is always in this area. However, the free ends of both ends of the anchoring branch 20 may be in this area or may cross this area during the movement. For example, when the anchoring branch 20 is too long, the end may cross the edge of the window when it swings.

[0071] See Figures 1-4 The anchoring branch 20 of the present invention includes an inner tube segment 21 and an outer tube segment 22 connected axially. The connection between the inner tube segment 21 and the outer tube segment 22 forms a circumferential connection point a. The first port portion 30a of the connecting membrane sleeve 30 is connected to the anchoring branch 20, and the second port portion 30b opposite to the first port portion 30a is connected to the main support 10 at the edge of the window opening, such that the inner tube segment 21 and the outer tube segment 22 are located on the inner and outer sides of the skirt 31 of the connecting membrane sleeve 30, respectively. The "first port portion 30a" and "second port portion 30b" mentioned in the present invention refer to a segment along the extension direction of the connecting membrane sleeve 30. It can be understood that the connecting membrane sleeve 30 may only include the first port portion 30a and the second port portion 30b, in which case the first port portion 30a and the second port portion 30b are connected. Alternatively, the connecting membrane sleeve 30 may include the first port portion 30a and the second port portion 30b, and a connecting segment connecting the first port portion 30a and the second port portion 30b. The extension length of the connecting membrane sleeve 30 can be set as needed. The connecting membrane sleeve 30 is a flexible membrane sleeve, and its shape can change under the action of force. The connecting membrane sleeve 30 can be made of one or more materials selected from expanded polytetrafluoroethylene, polyester, polyurethane, etc.

[0072] Specifically, for the movable anchoring branch 20, the anchoring branch 20 can move at least radially along the main support 10 to approach or move away from the central axis xx of the main support 10, that is, the anchoring branch 20 can be as follows: Figure 1 As shown, move upwards or as Figure 3 The downward movement, as shown, causes the connecting membrane sleeve 30 to protrude or retract relative to the main support 10. For example... Figure 1 and Figure 2 Anchoring branch 20 has at least the outermost protrusion furthest from the central axis of the main support 10, and as such Figure 3 and Figure 4 The diagram shows the innermost recessed position closest to the central axis of the main support 10. When... Figure 1 and Figure 2 As shown, when the anchoring branch 20 is in its outermost protruding position, the circumferential connection a is located above the surface where the window is located, and the connecting membrane sleeve 30 is in the shape of an outwardly protruding boss. When as Figure 3 and Figure 4As shown, when the anchoring branch 20 is in its innermost concave position, the circumferential connection a is located below the surface where the window is located, and the connecting membrane sleeve 30 is concave within concave. It can be understood that the outermost convex position and the innermost concave position are the extreme positions for the vertical movement of the anchoring branch 20. During its movement, the anchoring branch 20 also includes a transitional position between the outermost convex position and the innermost concave position.

[0073] Understandable, see reference Figure 1 and Figure 2 When in its most protruding position, the inner tube segment 21 is housed within the space enclosed by the boss-shaped connecting membrane sleeve 30. At this time, the free end of the inner tube segment 21 (i.e., the end furthest from the outer tube segment 22) may or may not extend beyond the inner surface of the main support 10. (See reference...) Figure 3 and Figure 4 When in the innermost recessed position, the outer tube segment 22 is completely contained within the space enclosed by the concave connecting membrane sleeve 30. At this time, the free end of the outer tube segment 22 (i.e. the end away from the inner tube segment 21) may or may not cross the outer surface of the main support 10.

[0074] In the covered stent, covered stent system, and covered stent fabrication method of the present invention, the inner and outer segments of the anchoring branch are configured to reduce both the external and internal bulge heights while maintaining sufficient anchoring length, thus avoiding the adverse effects of the branch being placed entirely externally or internally. The shorter internal height prevents encroachment on the main lumen of the main stent, ensuring hemodynamics. The limited range of motion at the end of the inner segment reduces the risk of stent breakage and prevents compression of adjacent branch openings. The shorter external height prevents the branch stent from rubbing against the vessel. More importantly, the anchoring branch can move freely and flexibly to match different vascular anatomy, providing a certain margin of error for the release of both the anchoring branch and the main stent, greatly reducing surgical difficulty and risk. Furthermore, the configuration of this application allows full utilization of the conical space at the root of the tissue branch during anchoring, thereby forming an effective anchoring length at that location, which significantly reduces the height of the internal and external bulges.

[0075] In this invention, the anchoring branch 20 can also swing relative to the main support 10, causing the anchoring branch 20 to be inclined. The central axis of the inclined anchoring branch 20 is not perpendicular to the axis of the main support 10. That is, the anchoring branch 20 can not only move up and down, but also swing in the circumferential direction, thereby adapting to different angles of the arch branch to match different vascular anatomy.

[0076] For example, the axial length of the anchoring branch 20 of the present invention is between 7mm and 10mm. This length range ensures anchoring of the branch stent 200, reducing metal irritation, endoleak risk, and the risk of branch abrasion of blood vessels. It also provides a certain margin of error for the release of both the branch stent 200 and the main stent, improving the success rate of the procedure and reducing the risk of complications. If the axial length of the anchoring branch 20 is too short, the stent may easily shift or detach under blood flow impact, and the modular stent connection may become disjointed or insufficiently overlapped. Poorly apposed areas of the anchoring branch and the branch stent edge may be directly exposed to blood flow, easily leading to thrombosis. Furthermore, if the anchoring is insufficient, once separation occurs, it is difficult to anchor the secondary stent, often requiring open surgery. Conversely, if the length is too long, the metal load is too high, increasing the risk of branch vessel occlusion, increasing the difficulty of delivery, increasing mechanical damage during stent implantation, and resulting in a lower margin of error for the main stent release.

[0077] In one embodiment, the length of the inner tube segment 21 is greater than the length of the outer tube segment 22. Preferably, the inner tube segment 21 accounts for about 3 / 5 of the length of the anchoring branch 20, and the outer tube segment 22 accounts for about 2 / 5 of the length of the anchoring branch 20. This further reduces the risk of the outer branch rubbing against blood vessels and the occurrence of compression, bending, and torsion between branches and branch blood vessels due to inaccurate placement of the main stent. The shorter outer branch makes it more flexible in the circumferential direction and also makes it less likely to scrape blood vessels, thereby improving the error tolerance rate and reducing the difficulty of the operation.

[0078] See Figure 6 As a connection method between the connecting membrane sleeve 30 and the anchoring branch 20, the anchoring branch 20 includes a branch skeleton 20a and a branch covering 20b. The connecting membrane sleeve 30 includes a skirt 31 and a tube sleeve 32 connected to the skirt 31. After the connecting membrane sleeve 30 is fitted onto the anchoring branch 20, the tube sleeve 32 and the branch covering 20b are fixedly connected. At this time, the inner tube section 21 and the outer tube section 22 are located on the inner and outer sides of the skirt 31 of the connecting membrane sleeve 30, respectively. The fixing method includes, but is not limited to, sewing and heat fusion. It can be understood that when the connecting membrane sleeve 30 includes a skirt 31 and a tube sleeve 32, the first port portion 30a is located on the tube sleeve 32, and the second port portion 30b is located on the skirt 31.

[0079] See Figure 7As another connection method between the connecting membrane sleeve 30 and the anchoring branch 20, the anchoring branch 20 includes a branch skeleton 20a and a branch covering 20b, while the connecting membrane sleeve 30 only includes a skirt 31. It can be understood that when the connecting membrane sleeve 30 only includes a skirt 31, the first port portion 30a is located at one end of the skirt 31, and the second port portion 30b is located at the other end of the skirt 31. After the skirt 31 of the connecting membrane sleeve 30 is fitted onto the anchoring branch 20, its first port portion 30a is relatively fixed to the branch covering 20b of the tube wall of the anchoring branch 20, thereby connecting the first port portion 30a of the connecting membrane sleeve 30 to the anchoring branch 20. The methods by which the first port portion 30a is relatively fixed to the tube wall of the anchoring branch 20 include, but are not limited to, sewing and heat fusion.

[0080] The designer of this application discovered during the actual design process that, although the above-mentioned connection method achieved the connection and solved the technical problems mentioned in the background art, it also had its shortcomings. Figure 6 While the proposed solution effectively guarantees connection strength, ensuring the flexibility of the anchoring branch 20 requires a thinner connecting membrane sleeve 30. However, excessive up-and-down movement of the anchoring branch 20 can cause holes to appear in the thinner connecting membrane sleeve 30, leading to internal leakage and branch breakage risks. Conversely, making the connecting membrane sleeve 30 thicker to prevent breakage would affect the flexibility of the anchoring branch 20, increasing the difficulty of matching the anchoring branch 20 with the bow branch and the access route. Figure 7 Although the skirt 31 connecting the membrane sleeve 30 does not restrict the flexibility of the anchoring branch 20, the way the end of the skirt 31 is connected to the anchoring branch 20 means that the connection strength between the two cannot be guaranteed, which poses a risk of breakage. In addition, the connection process is difficult and the manufacturing cost is high.

[0081] In view of the above issues, please refer to Figures 8-10Based on the aforementioned covered support, the present invention further proposes a covered support 100. In this embodiment, the anchoring branch 20 includes a branch skeleton 20a and a branch covering 20b. The branch covering 20b includes a fixed membrane 20b1 fixed relative to the branch skeleton 20a and a skirt membrane 20b2 movable relative to the branch skeleton 20a. The skirt membrane 20b2 extends from the circumferential connection a toward the side away from the outer tube section 22 and gradually away from the central axis of the anchoring branch 20. That is, the diameter of the skirt membrane 20b2 gradually increases from its fixed end to its free end. The connecting sleeve 30 may only include the skirt 31. The first port portion 30a of the skirt 31 is only fixedly connected to the skirt membrane 20b2. That is, the skirt 31 will not cross the circumferential connection a to connect with the fixed membrane 20b1 or the branch skeleton 20a, so as not to affect the flexibility of the anchoring branch 20. It is understood that when the connecting membrane sleeve 30 only includes the skirt sleeve 31, the first port portion 30a is located at one end of the skirt sleeve 31, and the second port portion 30b is located at the other end of the skirt sleeve 31. The method by which the first port portion 30a of the skirt sleeve 31 is fixed relative to the tube wall of the skirt membrane 20b2 includes, but is not limited to, sewing, heat fusion, etc. Preferably, as... Figure 9 As shown, to accommodate skirts 31 with different inner diameters and to ensure a good fit between the skirt 31 and the skirt edge film 20b2, the skirt edge film 20b2 includes multiple film-coated sheets 20b21, which are sequentially arranged around the outer periphery of the anchoring branch 20. For example, the multiple film-coated sheets 20b21 can be formed by cutting the skirt 31 along its extension direction, which ensures connection strength while simplifying the process. In this embodiment, the skirt 31 is connected to the skirt edge film 20b2 of the anchoring branch 20, ensuring both connection strength and stability. Simultaneously, the skirt 31 can be made thicker to prevent film breakage, and the increased thickness does not affect the flexibility of the anchoring branch 20. Therefore, this embodiment achieves three goals at once: ensuring connection strength, preventing film breakage, and improving the flexibility of the anchoring branch. Experimental results show that the membrane breakage rate is significantly reduced when using this embodiment, and the anchoring branch 20 is more flexible than the aforementioned scheme.

[0082] See Figure 11 and Figure 12 In one embodiment, the fixing membrane 20b1 includes an inner branch membrane 20b11 and an outer branch membrane 20b12 respectively disposed on the inner and outer walls of the branch frame 20a. The branch frame 20a is positioned between the inner branch membrane 20b11 and the outer branch membrane 20b12, and a skirt membrane 20b2 is connected to the outer branch membrane 20b12. Furthermore, to ensure connection strength and simplify the process, the outer branch membrane 20b12 and the skirt membrane 20b2 are integrally formed.

[0083] See Figure 11 and Figure 12 Preferably, the inner branch membrane 20b11, the outer branch membrane 20b12, and the skirt membrane 20b2 are integrally formed. Specifically, the branch skeleton 20a is sleeved on the tubular covering membrane 20c, and the side of the tubular covering membrane 20c near the outer tube segment 22 extends from the outer end m of the outer tube segment 22. The extended part is folded towards the side where the inner tube segment 21 is located and fixed to the branch skeleton 20a to form the outer branch membrane 20b12 on the outer tube segment 22. The remaining part after folding forms the skirt membrane 20b2 that can move relative to the branch skeleton 20a.

[0084] In other embodiments, in order to cover the branch skeleton 20a of the inner tube segment 21, the branch skeleton 20a is sleeved on the tubular covering film 20c, and the side of the tubular covering film 20c near the inner tube segment 21 extends from the outer end n of the inner tube segment 21. The extended part is folded towards the side where the outer tube segment 22 is located and fixed to the branch skeleton 20a to form the branch outer film 20b12 on the inner tube segment 21. The branch outer film 20b12 on the outer tube segment 22 and the branch outer film 20b12 on the inner tube segment 21 together constitute the branch outer film 20b12. The tubular covering film 20c attached to the inside of the branch skeleton 20a forms the branch inner film 20b11. The branch skeleton 20a is placed between the branch inner film 20b11 and the branch outer film 20b12 and the three are fixed relative to each other. The fixing method includes, but is not limited to, sewing, heat fusion and other methods. Preferably, the inner branch membrane 20b11 and the outer branch membrane 20b12 are tightly attached to the branch skeleton 20a by heat fusion. The folded-integral forming method in this embodiment not only simplifies the process of forming the skirt membrane 20b2, but also ensures the integrity of the covering while achieving connection, improving the connection strength between the coverings and between the coverings and the branch skeleton 20a. It also wraps around the end face of the main support 10, improving the end face sealing of the main support 10, effectively preventing the impact of blood flow on the junction of the inner and outer coverings at the end face, and avoiding tearing of the coverings on the inner and outer surfaces of the main support 10 under long-term impact from blood flow, as well as a series of adverse effects caused by covering tearing.

[0085] In one embodiment, the skirt cover 31 may include a single connecting film layer or multiple connecting film layers. When the skirt cover 31 includes only a single connecting film layer, the first port portion 30a of the connecting film layer is located above or below the skirt edge film 20b2 and is fixedly connected to the skirt edge film 20b2 after being fitted onto the outer periphery of the anchoring branch. Alternatively, in other embodiments, the skirt cover 31 includes multiple connecting film layers. In this case, all connecting film layers are fitted onto the outer periphery of the anchoring branch, and the skirt edge film 20b2 is located above or below all connecting film layers and is fixedly connected to the connecting film layers, or the skirt edge film 20b2 is located between two connecting film layers and is fixedly connected to the connecting film layers. Generally, the connecting film layers are set to 2 to 10 layers.

[0086] See Figure 13 The skirt cover 31 includes an annular region P near the circumferential connection a. At least a portion of the film thickness within the annular region P is greater than the film thickness of other areas of the skirt cover 31, or greater than the film thickness of the anchoring branch 20. In this embodiment, the film thickness of the annular region P near the circumferential connection a of the skirt cover 31 is relatively thick. This ensures that while the anchoring branch 20 has good flexibility, the annular region can provide good support for the anchoring branch 20, thereby allowing the anchoring branch 20 to stably maintain a certain state after flexible movement.

[0087] For example, such as Figure 7 As shown, the branch skeleton 20a includes a first branch wave loop 20a1 and a second branch wave loop 20a2, with the troughs of the first branch wave loop 20a1 and the peaks of the second branch wave loop 20a2 hooked together one by one. In this embodiment, the two branches are hooked together one by one, which ensures the flexibility and cavity integrity of the anchoring branch 20 and prevents the anchoring branch 20 from shortening axially.

[0088] See Figure 4 and Figure 5 The anchoring branch 20 is offset along the axial direction of the main stent 10 within the window area, making the anchoring branch 20 closer to the distal end of the window, i.e., closer to the right side as shown in the figure. The offset setting of the anchoring branch 20 serves two purposes: firstly, it prevents the deployed main stent 10 from being pulled backward, thus avoiding insufficient anchoring at the proximal end of the deployed main stent 10; secondly, the catheter guidewire is inserted into the branch vessel (such as the LSA) through the branch, with the stent branch edge (distal side) close to the edge of the vessel (such as the LSA), ensuring accurate axial positioning. Simultaneously, the offset branch, besides being close to the edge, provides greater flexibility within the contrast ring compared to a centrally located branch, compensating for stent radial positioning errors (e.g., if the vessel branch is at the 1 o'clock position, but the stent branch is placed at the 12 o'clock position during actual operation, the flexibility of the offset branch effectively compensates for this error, ensuring unobstructed blood flow.

[0089] See also Figure 4 A support ring 40 is fixed at the edge contour of the window opening, and the coating support 100 also includes a first developing element 50 disposed on the support ring 40. In one embodiment, the first developing element 50 is arranged around the support ring 40 once along the circumference of the support ring 40.

[0090] Regarding the aforementioned placement of the imaging element, the applicant has found in actual clinical practice that when it is wrapped around the stent once, the stent corrugation is compressed too tightly, and microcracks are easily generated at the crests and troughs of the stent corrugation, affecting the radial support performance of the stent and making the stent prone to poor deployment and causing internal leakage. Therefore, in other embodiments, the first imaging element 50 is only partially disposed on the support ring 40. For example, as shown... Figure 4 As shown, the first imaging element 50 is a C-shaped structure wound around a support ring 40. Preferably, the C-shaped first imaging element 50 is located on the proximal side of the support ring 40. In other embodiments, two C-shaped first imaging elements 50 are provided, with the two C-shaped first imaging elements 50 respectively located on the proximal and distal sides of the support ring 40. Clinical verification has shown that this arrangement of the first imaging element 50 largely solves the aforementioned internal leakage problem.

[0091] See Figure 2 and Figure 5 In other embodiments, the coating support 100 further includes a second developing element 60, which is fixed to the main support 10 and axially opposite to the proximal end of the window opening. Further, in other embodiments, the coating support 100 also includes a first keel 70, which is fixed to the main support 10 and extends along the length of the main support 10. The first keel 70 is located at the distal end of the window opening, and the second developing element 60 is axially opposite to the first keel 70. The first keel 70 is connected to the corrugated ring on the main support 10 via a steel sleeve 71. Exemplarily, the second developing element 60 is a figure-eight shaped developing point, with the apex of the figure-eight developing point less than 1.5 mm from the edge of the coating. Preferably, the keel is arranged vertically downwards along the figure-eight developing point in a straight line, with a left-right deflection angle of less than 10°. The stainless steel sleeve on the keel is more clearly visible under DSA imaging than the nickel-titanium wire. The operator can use the 8 imaging points or the keel-assisted stent for positioning. The keel corresponds precisely to the greater curvature of the blood vessel. Some fenestration procedures involve making a fenestration near the keel; in-situ fenestrations within the body can use the keel as a positioning reference. For example, in other embodiments, see [reference needed]. Figure 5 A window area 90 is pre-set on the pipe wall of the main support 10 on the distal side of the anchoring branch 20 so that the operator can perform window opening operations in this area.

[0092] Combination Figure 1 and Figure 14The exemplary film-coated support 100 of the present invention also includes a bare support 80 connected to one end of the main support 10. A film 81 is wrapped around the corrugated surface of the bare support 80 along the path of the corrugated surface. A portion of the bare support 80 near the end of the main support 10 extends into the main support 10 and is fixed relative to the main support 10. Specifically, the film 81 covers the surface of the bare support 80 along the path of the corrugated surface, making its surface smooth. During transport, it is hooked and connected to a U-shaped anchor in the conveyor. Upon release, the smooth-surfaced bare support 80 can quickly detach from the U-shaped anchor, thereby releasing the main support 10.

[0093] See Figure 15 and Figure 16 In other embodiments, the film-coated support 100 of the present invention further includes a branch support 200 detachably connected to the anchoring branch 20. The branch support 200 can be nested within the anchoring branch 20 and anchored to the anchoring branch 20. The branch support 200 includes an outwardly expanding section 201 near its proximal end. The outer diameter of the outwardly expanding section 201 gradually increases from its distal end to its proximal end. The maximum diameter of the outwardly expanding section 201 is greater than the inner diameter of the anchoring branch 20. When the branch support 200 is anchored to the anchoring branch 20, the outwardly expanding section 201 extends from the end of the inner tube section of the anchoring branch 20 and from the expanded portion, thereby limiting the axial direction of the anchoring branch 20.

[0094] Figures 17-20 This is a schematic diagram illustrating the structure of the anchoring branch 20 and the branch support 200 of the endovascular stent, an exemplary embodiment of the present invention, after connection in different tissue morphologies. Figure 17 In the case of a type I arch (where the distance between the midpoint of the brachiocephalic trunk opening and the apex of the arch is ≤ 1 times the diameter of the brachiocephalic trunk opening), and the angle between the centerline of the left subclavian artery (LSA) and the tangent of the LSA opening is > 60°, the anchoring branch 20 is protruding, and the connecting membrane sleeve is in the shape of an outwardly convex boss. The anchoring branch 20 is anchored to the branch support 200 at approximately perpendicular angles. Figure 18 In the case of a type I arch (where the distance between the midpoint of the brachiocephalic trunk opening and the apex of the arch is ≤1 times the diameter of the brachiocephalic trunk opening), and the angle between the centerline of the left subclavian artery (LSA) and the tangent of the LSA opening is ≤60°, the anchoring branch 20 is protruding, and the connecting membrane sleeve is in the shape of an outwardly convex boss. The anchoring branch 20 is anchored to the branch support 200 according to the tilt of the LSA. Figure 19In the case of a type II arch (where the distance between the tangent of the brachiocephalic trunk opening and the tangent of the left subclavian artery opening is greater than 1 times the diameter of the brachiocephalic trunk opening and less than or equal to 2 times the diameter of the brachiocephalic trunk opening), and the angle between the centerline of the left subclavian artery (LSA) and the tangent of the LSA opening is less than or equal to 60°, the anchoring branch 20 is protruding, and the connecting membrane sheath is in the shape of an outwardly convex boss. The anchoring branch 20 is anchored to the branch support 200 according to the tilt of the LSA. Compared to... Figure 18 , Figure 19 The tilt angle of anchor branch 20 in the middle is increased. Figure 20 In the case of a type III arch (where the distance between the tangent of the brachiocephalic trunk opening and the tangent of the left subclavian artery opening is greater than twice the diameter of the brachiocephalic trunk opening), and the angle between the centerline of the left subclavian artery (LSA) and the tangent of the LSA opening is ≤60°, the anchoring branch 20 is protruding, and the connecting membrane sheath is in the shape of an outwardly convex boss. The anchoring branch 20 is anchored to the branch stent 200 according to the tilt of the LSA. The anchoring branch of this invention, including an inner and outer tube segment, ensures sufficient anchoring length while allowing free and flexible movement to adapt to different vascular anatomy, reducing the encroachment on the main lumen space of the main stent, constraining the swing amplitude of the inner tube segment, and enhancing the stability of the anchoring branch.

[0095] The present invention also provides an exemplary film-coated support system, the support system including the film-coated support and the delivery device described above, the delivery device including a semi-binding structure, the semi-binding structure releasably binding the film so that the film is radially compressed or unbound.

[0096] The present invention also provides an exemplary method for manufacturing the above-mentioned covered stent 100, wherein the method for manufacturing the covered stent in this embodiment includes the following steps:

[0097] S1. Fabricate the main support frame 10; wherein, the main support frame 10 has window holes on its tube wall;

[0098] S2. Fabricate anchoring branch 20; wherein, the fabricated anchoring branch 20 includes an inner pipe section 21 and an outer pipe section 22 connected axially, and the connection between the inner pipe section 21 and the outer pipe section 22 forms a circumferential connection point a.

[0099] S3. Place the anchoring branch 20 on the side of the main support 10, and provide a connecting membrane sleeve 30 including a skirt 31. Connect the first port 30a of the connecting membrane sleeve 30 to the anchoring branch 20, and connect the second port 30b opposite to the first port 30a to the main support 10 at the edge of the window hole, so that the inner tube section 21 and the outer tube section 22 are located on the inner and outer sides of the skirt 31, respectively. When the central axis of the anchoring branch 20 is perpendicular to the central axis of the main support 10, the projection outline of the anchoring branch 20 in the plane where the window hole is located is within the ring of the window hole, and an annular area is formed between the projection outline and the window hole. The surface area of ​​the connecting membrane sleeve 30 is greater than the area of ​​the annular area. The order of steps S1 and S2 can be interchanged.

[0100] In one embodiment, see Figure 6 The anchoring branch 20 fabricated in step S2 includes a branch skeleton 20a and a branch covering 20b. The branch covering 20b includes a fixing membrane 20b1 fixed relative to the branch skeleton 20a. The connecting membrane sleeve 30 also includes a tube sleeve 32 connected to the skirt sleeve 31. After the connecting membrane sleeve 30 is fitted onto the anchoring branch 20, the tube sleeve 32 is fixedly connected to the fixing membrane 20b1. The fixing methods include, but are not limited to, sewing and heat fusion.

[0101] In another embodiment, see Figures 8-10 The anchoring branch 20 made in step S2 includes a branch skeleton 20a and a branch covering 20b. The branch covering 20b includes a fixed membrane 20b1 that is fixed relative to the branch skeleton 20a and a skirt membrane 20b2 that surrounds the outer periphery of the branch skeleton 20a and can move relative to the branch skeleton 20a. The skirt membrane 20b2 extends from the circumferential connection a toward the side away from the outer tube section 22 and gradually away from the central axis of the anchoring branch 20. The connecting membrane sleeve 30 only includes a skirt sleeve 31. The first port portion 30a and the second port portion 30b are located at the two ends of the skirt sleeve 31, respectively. The first port portion 30a of the skirt sleeve 31 is only fixedly connected to the skirt membrane 20b2.

[0102] Specifically, when the branch coating 20b includes a fixing film 20b1 and a skirt film 20b2, in one embodiment, step S2, which involves creating the anchoring branch 20, specifically includes:

[0103] Provide a branch liner (such as) Figure 11As illustrated in the diagram (Q), a branch inner membrane 20b11, a branch skeleton 20a, and a branch outer membrane 20b12 are sequentially arranged from the inside out on the branch liner. A skirt membrane 20b2 is provided so that it surrounds the outer periphery of the branch skeleton 20a, thereby fixing the branch inner membrane 20b11, branch skeleton 20a, and branch outer membrane 20b12 relatively, while connecting the skirt membrane 20b2 to the branch outer membrane 20b12. Fixing methods include, but are not limited to, sewing and heat fusion. Preferably, heat fusion is used to ensure that the branch inner membrane 20b11 and branch outer membrane 20b12 are tightly attached to the branch skeleton 20a.

[0104] In another embodiment, step S2, fabricating the anchoring branch 20, specifically includes: providing a branch liner (such as... Figure 11 As illustrated in the diagram (Q), a branch inner membrane 20b11 and a branch skeleton 20a are sequentially arranged from the inside out on the branch liner. An integral connecting membrane (a single, integral connecting membrane layer) is provided, located on the outer periphery of the branch skeleton 20a. A portion of the integral connecting membrane, the branch inner membrane 20b11, and the branch skeleton 20a are relatively fixed together. The remaining portion of the integral connecting membrane forms a skirt membrane 20b2 that can move relative to the branch skeleton 20a. Fixing methods include, but are not limited to, sewing and heat fusion. Preferably, heat fusion is used to ensure that the branch inner membrane 20b11 and the branch outer membrane 20b12 are tightly adhered to the branch skeleton 20a.

[0105] In another embodiment, see [reference] Figure 11 and Figure 12 Step S2, the fabrication of the anchoring branch 20, specifically includes: providing a branch liner Q; covering the branch liner Q with a tubular membrane 20c; fitting the branch skeleton 20a onto the branch liner with the tubular membrane 20c; and having the side of the tubular membrane 20c closest to the outer tube segment 22 extend from the outer end of the outer tube segment 22. Then, the extended portion is folded towards the side where the inner tube segment 21 is located and fixed to the branch skeleton 20a to form the branch outer membrane 20b12 on the inner tube segment 21. The remaining folded portion forms a skirt membrane 20b2 that can move relative to the branch skeleton 20a. Fixing methods include, but are not limited to, sewing and heat fusion. Preferably, heat fusion is used to ensure that the branch inner membrane 20b11 and the branch outer membrane 20b12 are tightly attached to the branch skeleton 20a. The folding and integral forming method of this embodiment not only simplifies the process of forming the skirt membrane 20b2, but also ensures the integrity of the membrane while achieving connection, improving the connection strength between membranes and between the membranes and the branch skeleton 20a. It wraps the end face of the main support 10, improves the sealing performance of the end face of the main support 10, effectively prevents the impact of blood flow on the junction of the inner and outer membranes of the end face, and avoids the tearing of the membranes on the inner and outer surfaces of the main support 10 under the long-term impact of blood flow, as well as a series of adverse effects caused by membrane tearing.

[0106] In this embodiment, the branch outer membrane 20b12 and the skirt membrane 20b2, which are fixed on the inner tube section 21 as needed, can be cut before or after folding to form multiple membrane sheets 20b21 arranged sequentially around the outer periphery of the anchoring branch 20. This method ensures the fit between the skirt 31 and the skirt membrane 20b2, guarantees the connection strength, and simplifies the process.

[0107] In this embodiment, the skirt 31 is connected to the skirt membrane 20b2 of the anchoring branch 20, ensuring the connection strength and stability. Simultaneously, the skirt 31 can be made thicker to prevent membrane breakage, and the increased skirt thickness does not affect the flexibility of the anchoring branch 20. This embodiment achieves three goals at once: ensuring connection strength, preventing membrane breakage, and improving the flexibility of the anchoring branch. Experimental verification shows that this embodiment significantly reduces the likelihood of membrane breakage, and compared to the aforementioned solutions, the anchoring branch 20 exhibits greater flexibility.

[0108] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0109] In the description of this specification, the references to terms such as "preferred embodiment," "another embodiment," "other embodiment," or "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in a suitable manner in any one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0110] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.

Claims

1. A covered stent, characterized in that, The system includes a tubular main support and a tubular anchoring branch, as well as a connecting membrane sleeve connecting the main support and the anchoring branch. The anchoring branch is used to engage with the branch support to anchor it. A window is formed in the wall of the main support. The anchoring branch is positioned within the area of ​​the window, and is eccentrically arranged along the axial direction of the main support within the window area, so that the anchoring branch is closer to the distal end of the window. When the central axis of the anchoring branch is perpendicular to the central axis of the main support, the projected outline of the anchoring branch in the plane of the window is within the annulus of the window, forming an annular region between the projected outline and the window. The surface area of ​​the connecting membrane sleeve is larger than the area of ​​the annular region. The anchoring branch includes an axially connected inner tube section and an outer tube section, with the connection between the inner tube section and the outer tube section forming a circumferential connection. The connecting membrane... The first port of the sleeve is connected to the anchoring branch, and the second port opposite to the first port is connected to the main support at the edge of the window. The connecting sleeve is a flexible sleeve, and its shape can change under force. The connecting sleeve includes a skirt, with the inner tube section and the outer tube section located on the inner and outer sides of the skirt, respectively. The anchoring branch can move at least radially along the main support to approach or move away from the central axis of the main support. The anchoring branch has at least an outermost protruding position farthest from the central axis of the main support and an innermost recessed position closest to the central axis of the main support. When in the outermost protruding position, the circumferential connection is located above the surface where the window is located, and the connecting sleeve is in the shape of an outwardly convex boss. When in the innermost recessed position, the circumferential connection is located below the surface where the window is located, and the connecting sleeve is in the shape of an inwardly concave ...

2. The covered stent according to claim 1, characterized in that, The anchoring branch includes a branch skeleton and a branch covering film. The branch covering film includes a fixing film that is fixed relative to the branch skeleton. The connecting film sleeve also includes a tube sleeve that is connected to the skirt sleeve. After the connecting film sleeve is fitted onto the anchoring branch, the tube sleeve is fixedly connected to the fixing film.

3. The covered stent according to claim 1, characterized in that, The anchoring branch includes a branch skeleton and a branch covering film. The branch covering film includes a fixed film that is fixed relative to the branch skeleton and a skirt film that surrounds the outer periphery of the branch skeleton and can move relative to the branch skeleton. The skirt film extends from the circumferential connection point toward the side away from the outer tube section and gradually away from the central axis of the anchoring branch. The connecting film sleeve only includes the skirt sleeve. The first port portion and the second port portion are respectively located at the two ends of the skirt sleeve. The first port portion of the skirt sleeve is fixedly connected only to the skirt film.

4. The covered stent according to claim 3, characterized in that, The fixing membrane includes an inner branch membrane and an outer branch membrane respectively disposed on the inner and outer walls of the branch skeleton, the branch skeleton is placed between the inner branch membrane and the outer branch membrane, and the skirt membrane is connected to the outer branch membrane.

5. The covered stent according to claim 4, characterized in that, The branch outer membrane and the skirt membrane are integrally formed.

6. The covered stent according to claim 5, characterized in that, The inner branch membrane, the outer branch membrane, and the skirt membrane are integrally formed. The branch skeleton is sleeved on the tubular covering membrane, and the side of the tubular covering membrane near the outer tube segment extends from the outer end of the outer tube segment. The extended part is folded towards the side where the inner tube segment is located and then fixed to the branch skeleton to form the outer branch membrane on the inner tube segment. The remaining part after folding forms the skirt membrane that can move relative to the branch skeleton.

7. The covered stent according to claim 3, characterized in that, The skirt cover includes a connecting membrane layer, which is fitted onto the outer periphery of the anchoring branch, with its first port located above or below the skirt edge membrane and fixedly connected to the skirt edge membrane; or, The skirt cover includes at least two connecting membrane layers, all of which are sleeved on the outer periphery of the anchoring branch. The skirt edge membrane is located above or below all of the connecting membrane layers and is fixedly connected to the connecting membrane layers, or the skirt edge membrane is located between two of the connecting membrane layers and is fixedly connected to the connecting membrane layers.

8. The covered stent according to claim 3, characterized in that, The skirt cover includes an annular region near the circumferential connection, and at least a portion of the film thickness within the annular region is greater than the film thickness of other regions of the skirt cover.

9. The covered stent according to any one of claims 3 to 8, characterized in that, The skirt membrane includes multiple covering sheets, which are arranged sequentially around the outer periphery of the anchoring branch.

10. The covered stent according to any one of claims 1 to 3, characterized in that, The length of the anchoring branch is between 7mm and 10mm; and / or, the length of the inner pipe section is greater than the length of the outer pipe section.

11. The covered stent according to any one of claims 1 to 3, characterized in that, A support ring is fixed at the edge contour of the window opening, and the coating bracket also includes a first developing element disposed on the support ring, wherein the first developing element is only partially disposed on the support ring.

12. The covered stent according to any one of claims 1 to 3, characterized in that, It also includes a second developing element, which is fixed to the main support and is located axially opposite to the proximal end of the window. The coating support also includes a first keel, which is fixed to the main support and extends along the length of the main support. The first keel is located at the distal end of the window, and the second developing element is axially opposite to the first keel.

13. The covered stent according to any one of claims 1 to 3, characterized in that, It also includes a bare bracket connected to one end of the main support, wherein the wave loop of the bare bracket is covered with a membrane along the path of the wave loop, and the portion of the bare bracket near the main support extends into the main support and is fixed relative to the main support.

14. The covered stent according to any one of claims 1 to 3, characterized in that, It also includes a branch bracket detachably connected to the anchoring branch, the branch bracket being nested within the anchoring branch and anchored to the anchoring branch; wherein, the branch bracket includes an outwardly expanding section near its proximal end, the outer diameter of the outwardly expanding section gradually increasing from its distal end to its proximal end, the maximum diameter of the outwardly expanding section being greater than the inner diameter of the anchoring branch, and when anchored to the anchoring branch, the outwardly expanding section extends from the end of the inner tube section of the anchoring branch.

15. A covered scaffold system, characterized in that, The covered stent system includes a covered stent and a delivery device as described in any one of claims 1 to 14, the delivery device including a semi-binding structure that releasably binds the covered stent to radially compress or release the covered stent.

16. A method for manufacturing a covered scaffold, characterized in that, Includes the following steps: S1. Fabricate the main support frame; wherein, the main support frame has window holes on its tube wall; S2. Fabricate an anchoring branch; wherein the fabricated anchoring branch includes an inner pipe section and an outer pipe section that are axially connected, the connection between the inner pipe section and the outer pipe section forms a circumferential connection, and the anchoring branch is used to fit into a branch support to anchor the branch support. S3. The anchoring branch is placed on the side of the main support, and a connecting membrane sleeve including a skirt is provided. The connecting membrane sleeve is a flexible membrane sleeve, and its shape can change under force. The first port of the connecting membrane sleeve is connected to the anchoring branch, and the second port opposite to the first port is connected to the main support at the edge of the window hole, so that the inner tube section and the outer tube section are located on the inner and outer sides of the skirt, respectively. The anchoring branch is eccentrically arranged in the window hole area along the axial direction of the main support, so that the anchoring branch is closer to the far end of the window hole. When the central axis of the anchoring branch is perpendicular to the central axis of the main support, the projection outline of the anchoring branch in the plane where the window hole is located is inside the ring of the window hole, and the projection outline and the window hole form an annular area. The surface area of ​​the connecting membrane sleeve is larger than the area of ​​the annular area. The anchoring branch is at least radially movable along the main support to approach or move away from the central axis of the main support. The anchoring branch has at least an outermost protruding position farthest from the central axis of the main support and an innermost recessed position closest to the central axis of the main support. When in the outermost protruding position, the circumferential connection is located above the surface where the window is located, and the connecting membrane sleeve is in the shape of an outwardly protruding boss. When in the innermost recessed position, the circumferential connection is located below the surface where the window is located, and the connecting membrane sleeve is in the shape of an inwardly concave ... The order of steps S1 and S2 can be interchanged.

17. The method for manufacturing a covered scaffold according to claim 16, characterized in that, The anchoring branch fabricated in step S2 includes a branch skeleton and a branch covering. The branch covering includes a fixing membrane fixed relative to the branch skeleton. The connecting membrane sleeve also includes a tube sleeve connected to the skirt sleeve. After the connecting membrane sleeve is fitted onto the anchoring branch, the tube sleeve is fixedly connected to the fixing membrane; or, The anchoring branch manufactured in step S2 includes a branch skeleton and a branch covering. The branch covering includes a fixed membrane that is fixed relative to the branch skeleton and a skirt membrane that surrounds the outer periphery of the branch skeleton and can move relative to the branch skeleton. The skirt membrane extends from the circumferential connection point toward the side away from the outer tube section and gradually away from the central axis of the anchoring branch. The connecting membrane sleeve only includes the skirt sleeve. The first port portion and the second port portion are respectively located at the two ends of the skirt sleeve. The first port portion of the skirt sleeve is fixedly connected only to the skirt membrane.

18. The method for manufacturing a covered scaffold according to claim 17, characterized in that, When the branch coating being fabricated includes a fixing film and a skirt film, step S2, which involves fabricating the anchoring branch, specifically includes: A branch liner is provided, on which a branch inner membrane, a branch skeleton, and a branch outer membrane are sequentially arranged from the inside to the outside. A skirt membrane is provided such that it surrounds the outer periphery of the branch skeleton, thereby fixing the branch inner membrane, branch skeleton, and branch outer membrane relatively. Simultaneously, the connecting section of the skirt membrane is connected to the branch outer membrane; or... A branch liner is provided, on which a branch inner membrane and a branch skeleton are sequentially disposed from the inside out; an integral connecting membrane is provided, the integral connecting membrane being disposed on the outer periphery of the branch skeleton, and a portion of the integral connecting membrane being fixed relative to the branch inner membrane and the branch skeleton, the remaining portion of the integral connecting membrane forming a skirt membrane movable relative to the branch skeleton; or, A branch liner is provided, and a tubular film is covered on the branch liner. The branch skeleton is fitted onto the branch liner with the tubular film, and the side of the tubular film near the outer tube segment extends from the outer end of the outer tube segment. Then, the extended part is folded towards the side where the inner tube segment is located and fixed to the branch skeleton to form the branch outer film on the inner tube segment. The remaining part after folding forms the skirt film that can move relative to the branch skeleton.

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