Tubular covered structure, its preparation method and covered stent

Abstract

The present invention discloses a tubular covered structure, a preparation method thereof, and a covered stent. The tubular covered structure includes a main body, a closed part, and two or more branch pipe bodies. One end of the main body is respectively connected and communicated with each of the branch pipe bodies. The closed part is arranged between at least one pair of adjacent branch pipe bodies, and the closed part is arranged in the transition area where at least one pair of adjacent branch pipe bodies are connected to each other. The closed part is hermetically connected to the main body and each of the branch pipe bodies respectively to prevent blood from oozing out from the transition area. The covered stent includes the above-mentioned tubular covered structure and a stent main body, and the tubular covered structure is coated on the outer surface of the stent main body. The tubular covered structure has a small amount of blood oozing.

Description

Technical Field

[0001] The present invention relates to the field of medical devices for treating intravascular diseases, and in particular to a tubular coated structure and a preparation method thereof, and a coated stent. Background Art

[0002] In recent years, in the medical field, covered stents have gradually become the mainstream products of artificial blood vessels. Covered stents are composed of a coating and a metal stent, and the coating mainly plays a blood blocking role. The coating material is generally polyester, polyurethane, polytetrafluoroethylene, silk, etc., and the coating structure is plain, twill, satin and their variations. The diseased blood vessels are divided into thoracic main blood vessels and abdominal main blood vessels according to the location of the lesions. According to the characteristics of the lesion location, the covered stent used for the abdominal main blood vessels is a double-branch shape, which determines that the coating used for this covered stent must also be a double-branch structure.

[0003] Currently, the stent graft structures on the market are usually made in two processing methods. The first is to sew a flat stent graft into a tubular stent graft structure. However, the sutures of the stent graft structure not only cause bleeding, but also increase the release resistance of the stent graft. The second is to directly weave a tubular stent graft structure in an integrated molding method. Figure 1 However, when the main body 20 (thicker tube) transitions to the branch pipe 21 and the branch pipe 22, a larger hole will be left at the connection between the main body 20 and the branch pipe 21 and the branch pipe 22. Figure 2 The structure shown at A in the figure is a structural defect caused by the existing one-piece molding weaving process. This structural defect causes a large amount of bleeding at the connection between the three tubes of the coated stent. Currently, it is usually remedied by suturing the holes, but bleeding will still exist in the sutured area.

[0004] Therefore, no matter how the tubular membrane structure is manufactured, there is inevitably the problem of bleeding at the connection between the three tubes, which has become a technical problem that needs to be solved urgently in this field. Summary of the invention

[0005] Based on this, it is necessary to provide a tubular coating structure and a preparation method thereof that can effectively solve the problem of large bleeding in the transition area between the main body and the branches of the traditional coating structure.

[0006] The present invention provides a tubular coating structure, comprising a main body, at least one closing portion and two or more branch tube bodies, wherein the main body is respectively connected and communicated with one end of each of the branch tube bodies, and the closing portion is provided in a transition area connected to each other between at least one pair of adjacent two branch tube bodies, and the closing portion is respectively closed and connected with the main body and the at least one pair of adjacent two branch tube bodies to prevent blood from seeping out of the transition area.

[0007] As used herein, "adjacent" in the statement "a sealing portion is provided between at least one pair of adjacent branch pipe bodies" means that there are no other branch pipe bodies or barriers between two branch pipe bodies, and does not refer to the closest branch pipe bodies selected in the case of multiple branch pipe bodies; "sealing connection" in the statement "the sealing portion is hermetically connected to the main pipe body and each of the branch pipe bodies respectively" means that when blood flows from the main pipe body or a branch pipe body to the sealing portion, it will encounter resistance and cannot flow smoothly into and / or out of the sealing portion, but does not mean that blood flow must be completely blocked.

[0008] In one embodiment, the sealing portion has a planar structure.

[0009] In one embodiment, the sealing portion has a single-layer planar structure.

[0010] In one embodiment, the length of the sealing portion is 1 mm - 10 mm, and the width is 1 mm - 8 mm.

[0011] In one embodiment, the sealing portion has a plain weave structure.

[0012] In one embodiment, the sealing portion is provided in the transition region where each pair of adjacent branch pipe bodies are connected to each other.

[0013] In one embodiment, the sealing portion has a first sealing end and a second sealing end. At least one pair of adjacent branch pipe bodies includes a first branch pipe body and a second branch pipe body. The first branch pipe body and the second branch pipe body are spaced apart by the sealing portion in the radial direction of the first branch pipe body. The main pipe body is connected to the sealing portion at the first sealing end, and at least one pair of adjacent branch pipe bodies are separated at the second sealing end.

[0014] In one embodiment, the first sealing end has a rectangular edge, the second sealing end has an arc-shaped edge, and the arc-shaped edge is a structure recessed toward the first sealing end.

[0015] In one embodiment, the shape of the sealing portion is a polygon.

[0016] In one embodiment, the sum of the inner diameters of the respective branch pipe bodies is equal to the inner diameter of the main pipe body.

[0017] In one embodiment, the sealing portion, the main pipe body, and each of the branch pipe bodies are integrally braided and formed.

[0018] A method for preparing the tubular film-covered structure as described above, comprising:

[0019] Weave the weft yarn with the upper warp yarn and the lower warp yarn respectively to form the main pipe body;

[0020] Weave the weft yarn with some of the upper warp yarn and some of the lower warp yarn respectively to form two or more branch pipe bodies. During the formation of each branch pipe body, merge some of the upper warp yarn and some of the lower warp yarn into the same-layer warp yarn, and use the same-layer warp yarn and the weft yarn to weave the closed part in the transition area where at least a pair of adjacent branch pipe bodies are connected.

[0021] In one embodiment, at least a pair of adjacent branch pipe bodies includes a first branch pipe body and a second branch pipe body. The step of using the same-layer warp yarn and the weft yarn to weave the closed part between the at least a pair of adjacent branch pipe bodies includes:

[0022] Divide some of the upper warp yarn into a first upper warp yarn and a second upper warp yarn, and divide some of the lower warp yarn into a first lower warp yarn and a second lower warp yarn;

[0023] Weave the weft yarn with the first upper warp yarn, the first lower warp yarn, the merged same-layer warp yarn, the second upper warp yarn and the second lower warp yarn respectively to simultaneously form part of the first branch pipe body, the closed part and part of the second branch pipe body, and make the closed part located in the transition area where part of the first branch pipe body is connected to part of the second branch pipe body;

[0024] Restore the same-layer warp yarn to some of the upper warp yarn and some of the lower warp yarn, divide some of the other upper warp yarn into a third upper warp yarn and a fourth upper warp yarn, and divide some of the other lower warp yarn into a third lower warp yarn and a fourth lower warp yarn;

[0025] Weave the weft yarn with the first upper warp yarn, the first lower warp yarn, the third upper warp yarn and the third lower warp yarn respectively to form the remaining first branch pipe body, and use the weft yarn to weave the remaining second branch pipe body with the second upper warp yarn, the second lower warp yarn, the fourth upper warp yarn and the fourth lower warp yarn respectively, so as to obtain the complete first branch pipe body and the second branch pipe body.

[0026] The tubular film-covered structure of the present invention can not only solve the problem that there is a large amount of blood leakage in the transition area between the main body and the branches of the film of the traditional abdominal aortic film-covered stent, but also be applicable to the film-covered structures with multiple other branches, improve the safety and effectiveness of the film-covered structure, reduce the amount of blood leakage, and improve the product performance.

[0027] The present invention also provides a film-covered stent.

[0028] The described covered stent includes the described tubular covered structure and the stent body, and the tubular covered structure is wrapped around the outer surface of the stent body.

[0029] Compared with the traditional hand-sewn or integrally formed covered structure, the tubular covered structure of the present invention has a reliable seal in the transition area between the main body and the branches, with a lower or almost no blood leakage, effectively avoiding the blood leakage phenomenon through holes caused by the knitting process in the prior art. Moreover, the manufacturing process can effectively improve the processing efficiency, eliminating the need for later manual sewing, saving labor costs, and being suitable for wide promotion and application. Description of the Drawings

[0030] Figure 1 is the front view of the tubular covered structure in the prior art;

[0031] Figure 2 is the top view of the tubular covered structure in the prior art;

[0032] Figure 3 is the front view of the tubular covered structure according to an embodiment of the present invention;

[0033] Figure 4 is Figure 3 the enlarged schematic view of the structure at position B of the shown tubular covered structure.

[0034] Description of the Reference Numerals

[0035] 10: Tubular covered structure; 100: Main pipe body; 200: First branch pipe body; 300: Second branch pipe body; 400: Closed part; 40a: First closed end; 400b: Second closed end; 20: Main pipe; 21, 22: Branch pipes. Detailed Embodiments

[0036] To facilitate the understanding of the present invention, the present invention will be described more comprehensively below with reference to the relevant drawings. The preferred embodiments of the present invention are shown in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, these embodiments are provided to make the understanding of the disclosure of the present invention more thorough and comprehensive.

[0037] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which the present invention belongs. The terms used in the description of the present invention in this specification are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0038] An embodiment of the present invention provides a covered stent. The covered stent includes a tubular covered structure and a stent body, and the tubular covered structure is coated on the outer surface of the stent body.

[0039] See Figure 3 As shown, the above-mentioned tubular covered structure 10 includes a main body 100, a first branch body 200, a second branch body 300, and a closing part 400.

[0040] In one embodiment, the first branch body 200 and the second branch body 300 are arranged in parallel. One end of the main body 100 is a blood inlet end, and the other end is respectively connected and communicated with one end of the first branch body 200 and one end of the second branch body 300. The other ends of the first branch body 200 and the second branch body 300 are blood outlet ends. The closing part 400 is respectively connected to the main body 100, the first branch body 200, and the second branch body 300. Further, the closing part 400 is respectively hermetically connected to the main body 100, the first branch body 200, and the second branch body 300, and the closing part 400 is located in the transition area where the first branch body 200 and the second branch body 300 are connected, and is used to prevent blood from leaking out of this transition area.

[0041] Preferably, the closing part 400 is integrally woven and formed with the main body 100, the first branch body 200, and the second branch body 300, and the closing part 400 has a planar structure, and is further preferably a single-layer structure and / or a plain weave structure. The single-layer planar structure can provide better flexibility and foldability to the closing part, which is beneficial to coating the tubular covered structure 10 on the stent body, and is also beneficial to loading the covered stent on the delivery device. The plain weave structure has the characteristic of high tightness and can further provide good anti-leakage performance. Of course, in other embodiments, the closing part 400 can also be a twill, satin structure, or a multi-layer structure, and the present invention does not limit this.

[0042] As Figure 4 shown, the closing part 400 is substantially rectangular, and has a first closing end 400a and a second closing end 400b. The first branch body 200 and the second branch body 300 are spaced apart by the closing part 400 in the radial direction of the first branch body 200, and the main body 100 is connected to the closing part 400 at the first closing end 400a, and the first branch body 200 and the second branch body 300 are separated at the second closing end 400b.

[0043] Compared with the method of connecting the first branch tube body 200 and the second branch tube body 300 by suturing in the prior art, the closing part provided in this embodiment can not only avoid the blood leakage caused by the small holes caused by suturing, but also strengthen the strength of the connection area between the first branch tube body 200 and the second branch tube body 300, and further improve the reliability of sealing.

[0044] Further referring to Figure 4 , preferably, the first closed end 400a of the closing part 400 has a rectangular edge, while the second closed end 400b of the closing part 400 has an arc-shaped edge, and the arc-shaped edge is a structure recessed towards the first closed end 400a. This design can make the first branch tube body 200 and the second branch tube body 300 have more flexibility, and effectively prevent the tearing at the second closed end 400b caused by the relative movement between the first branch tube body 200 and the second branch tube body 300.

[0045] Those skilled in the art can understand that in other embodiments, the structure and shape of the closing part 400 are not limited to this. The structure and shape of the closing part 400 can also be designed according to the shapes and relative positional relationships of the first branch tube body 200 and the second branch tube body 300. For example, the closing part 400 can also be a polygon such as a triangle or a trapezoid, and the present invention is not only applicable to the film-covered structure with two branch tube bodies, but also applicable to the film-covered structure with three or more branch tube bodies. The present invention makes no limitation in this regard.

[0046] In one embodiment, the length of the closing part 400 along the axial direction of the main tube body 100 is 1 mm - 10 mm. For example, the length of the closing part 400 is 1 mm, 2 mm, 5 mm, 10 mm or other non-integer values. The width of the closing part 400 along the radial direction of the main tube body 100 is 1 mm - 8 mm. For example, the width of the closing part 400 is 1 mm, 2 mm, 5 mm, 8 mm or other non-integer values.

[0047] In one embodiment, the outer peripheral surfaces of the main tube body 100, the first branch tube body 200 and the second branch tube body 300 are smoothly transitionally connected.

[0048] The tubular film-covered structure 10 of the present invention can solve the problem of large blood leakage in the transition area between the film of the traditional abdominal aortic film-covered stent and the branches. The closing part 400 can effectively avoid the generation of holes in the branches of the main tube body 100, the first branch tube body 200 and the second branch tube body 300 of the film, reduce the blood leakage amount of the film, and effectively improve the safety and effectiveness of the film-covered stent artificial blood vessel.

[0049] This embodiment also relates to a preparation method of the tubular film-covered structure 10.

[0050] In this embodiment, the loom needs to use two shuttles, each shuttle drives a weft yarn respectively, and the warp yarns are divided into upper warp yarns and lower warp yarns. Of course, in other embodiments, more than two shuttles can also be used to weave more than two branch pipe bodies, and the present invention does not limit this. The tubular film structure 10 is integrally woven by weft yarns, upper warp yarns and lower warp yarns.

[0051] Specifically, first, the first shuttle drives the weft yarn to be woven with the upper warp yarns and the lower warp yarns respectively to form the upper and lower two surfaces of a partial main pipe body, and the upper and lower two surfaces are used to form the upper half pipe and the lower half pipe of the main pipe body. During the weaving process, the upper half pipe and the lower half pipe are connected to form the main pipe body, and the main pipe body has a first predetermined width.

[0052] Then, part of the upper warp yarns are divided into first upper warp yarns and second upper warp yarns, part of the lower warp yarns are divided into first lower warp yarns and second lower warp yarns, and the remaining predetermined number of upper warp yarns and lower warp yarns are combined into the same-layer warp yarns. Preferably, the width of the same-layer warp yarns is 0.5 cm - 3 cm. Continue to use the first shuttle to drive the weft yarn to be woven together with the first upper warp yarns, the first lower warp yarns, the combined same-layer warp yarns, the second upper warp yarns and the second lower warp yarns to form part of the first branch pipe body 200, the closed part 400 and part of the second branch pipe body 300. That is, the first upper warp yarns, the first lower warp yarns and the weft yarn are woven into part of the first branch pipe body 200, the combined same-layer warp yarns and the weft yarn are woven into the closed part 400, and the second upper warp yarns, the second lower warp yarns and the weft yarn are woven into part of the second branch pipe body 300. The closed part 400 is located in the transition area where part of the first branch pipe body 200 is connected to part of the second branch pipe body 300. More specifically, the closed part 400 is located between part of the first branch pipe body 200 and part of the second branch pipe body 300. The closed part 400 has a second predetermined width, and the width of the closed part is 0.5 cm - 3 cm, that is, the same as the width of the same-layer warp yarns.

[0053] Restore the above-mentioned same-layer warp yarns to a predetermined number of upper warp yarns and lower warp yarns, divide the upper warp yarns into third upper warp yarns and fourth upper warp yarns, divide the lower warp yarns into third lower warp yarns and fourth lower warp yarns. The third upper warp yarns and the third lower warp yarns are used to weave the remaining first branch pipe body 200, and the fourth upper warp yarns and the fourth lower warp yarns are used to weave the second branch pipe body 300.

[0054] The first shuttle is used to continue driving the weft yarn to weave the remaining first branch tube body 200 with the first upper warp yarn, the first lower warp yarn, the third upper warp yarn, and the third lower warp yarn, thereby weaving the complete first branch tube body 200. Meanwhile, a second shuttle is introduced to drive the weft yarn to weave the remaining second branch tube body 300 with the second upper warp yarn, the second lower warp yarn, the fourth upper warp yarn, and the fourth lower warp yarn, thereby weaving the complete second branch tube body 300. The first branch tube body 200 has a third predetermined width, and the second branch tube body 300 has a fourth predetermined width.

[0055] It can be understood that during the weaving process of the first branch tube body 200 and the second branch tube body 300, the first upper warp yarn and the third upper warp yarn are used to weave the upper half tube of the first branch tube body 200 with the weft yarn, and the first lower warp yarn and the third lower warp yarn are used to weave the lower half tube of the first branch tube body 200 with the weft yarn; the second upper warp yarn and the fourth upper warp yarn are used to weave the upper half tube of the second branch tube body 300 with the weft yarn, and the second lower warp yarn and the fourth lower warp yarn are used to weave the lower half tube of the second branch tube body 300 with the weft yarn; the upper half tube of the first branch tube body 200 is connected to the lower half tube of the first branch tube body 200 to form the complete first branch tube body 200, and the upper half tube of the second branch tube body 300 is connected to the lower half tube of the second branch tube body 300 to form the complete second branch tube body 300.

[0056] In this embodiment, the third predetermined width is the same as the fourth predetermined width. The first predetermined width is the sum of the second predetermined width, the third predetermined width, and the fourth predetermined width. Of course, in other embodiments, the widths of each part can also be designed according to the branching characteristics of the tubular film structure 10. The upper yarns and the lower yarns can also be divided into more parts for weaving more branch tube bodies. When weaving, the branch tube bodies can also be woven first and then the main tube body. The present invention places no restrictions on this.

[0057] The preparation method of the tubular film structure of the present invention has a simple process. Compared with the traditional manual stitching method, it saves time and effort, and the sealing effect of the produced tubular film structure is better, and the blood seepage volume is significantly reduced.

[0058] Compared with the tubular membrane covered stent in the prior art, the tubular covered structure of the present invention can significantly reduce the amount of blood leakage. In the laboratory, the inventor used water flow instead of blood flow according to the industry standard test method to test the covered structure a with holes in the transition area between two adjacent branch pipe bodies in the prior art, the covered structure b with the holes in the transition area between two adjacent branch pipe bodies sutured, and the covered structure c of the embodiment of the present invention with a closed part (8 mm in length and 1 mm in width) arranged in the transition area between two adjacent branch pipe bodies. There are 3 covered structures a, b, and c respectively, and the following data can be obtained: the average water leakage amount in the transition area of the covered structure a is 360 ml / min / cm 2 , and the average water leakage amount in the transition area of the covered structure b is: 240 ml / min / cm 2 , and the average water leakage amount in the transition area of the covered structure c is: 58 ml / min / cm 2 . In the best case, the average water leakage amount in the transition area of the covered structure c is almost zero. From the above comparison, it can be seen that the tubular covered structure in the above embodiment of the present invention can effectively reduce the amount of blood leakage during stent surgery.

[0059] The technical features of the above embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope recorded in this specification.

[0060] The above embodiments only represent several implementation manners of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the patent of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several deformations and improvements can still be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention should be subject to the appended claims.

Claims

1. A tubular film-covered structure, characterized in that, It includes a main tube body, at least one closed portion, and two or more branch tube bodies. Among them, the main tube body is formed by weaving weft yarn with the upper warp yarn and the lower warp yarn respectively. The branch tube bodies are formed by weaving the weft yarn with part of the upper warp yarn and part of the lower warp yarn respectively. The closed portion is woven with the weft yarn using the same-layer warp yarn formed by combining another part of the upper warp yarn and another part of the lower warp yarn. One end of the main tube body is respectively connected and communicated with each of the branch tube bodies. The closed portion is arranged in the transition area where at least a pair of adjacent two branch tube bodies are connected to each other. The closed portion is hermetically connected to the main tube body and the at least a pair of adjacent two branch tube bodies respectively, so as to prevent blood from oozing out from the transition area.

2. The tubular film-coated structure according to claim 1, wherein The closed portion has a planar structure.

3. The tubular film-covered structure according to claim 2, characterized in that, The closed portion has a single-layer planar structure.

4. The tubular film-covered structure according to claim 2, wherein, The length of the closed portion is 1 mm - 10 mm, and the width is 1 mm - 8 mm.

5. The tubular film-covered structure according to any one of claims 1-4, characterized in that, The closed portion has a plain weave structure.

6. The tubular film-covered structure according to any one of claims 1-4, characterized in that, The closed portion is arranged in the transition area where each pair of adjacent two branch tube bodies are connected to each other.

7. The tubular film-covered structure according to any one of claims 1-4, characterized in that, The closed portion has a first closed end and a second closed end. At least a pair of adjacent two branch tube bodies include a first branch tube body and a second branch tube body. And the first branch tube body and the second branch tube body are spaced apart by the closed portion in the radial direction of the first branch tube body. And the main tube body is connected to the closed portion at the first closed end. At least a pair of adjacent two branch tube bodies are separated at the second closed end.

8. The tubular film-covered structure according to claim 7, characterized in that, The first closed end has a rectangular edge, and the second closed end has an arc-shaped edge, and the arc-shaped edge is a structure recessed towards the first closed end.

9. The tubular film-covered structure according to any one of claims 1-4, characterized in that, The shape of the closed portion is a polygon.

10. The tubular film-covered structure according to any one of claims 1-4, characterized in that, The sum of the inner diameters of each of the branch tube bodies is equal to the inner diameter of the main tube body.

11. The tubular film-covered structure according to any one of claims 1-4, characterized in that, The closed portion and the main tube body, each of the branch tube bodies are integrally woven and formed.

12. A method for preparing the tubular film-covered structure according to any one of claims 1-11, characterized in that, It includes: Weaving the weft yarn with the upper warp yarn and the lower warp yarn respectively to form the main tube body; Weaving the weft yarn with part of the upper warp yarn and part of the lower warp yarn respectively to form two or more branch tube bodies. During the process of forming each of the branch tube bodies, combining another part of the upper warp yarn and another part of the lower warp yarn into the same-layer warp yarn, and using the same-layer warp yarn and the weft yarn to weave the closed portion in the transition area where at least a pair of adjacent two branch tube bodies are connected.

13. The preparation method of the tubular film-covered structure according to claim 12, wherein, At least a pair of adjacent two branch tube bodies include a first branch tube body and a second branch tube body. The step of weaving the closed portion with the same-layer warp yarn and the weft yarn between the at least a pair of adjacent two branch tube bodies includes: Dividing part of the upper warp yarn into a first upper warp yarn and a second upper warp yarn, and dividing part of the lower warp yarn into a first lower warp yarn and a second lower warp yarn; The weft yarns are respectively woven together with the first upper warp yarns, the first lower warp yarns, the combined warp yarns of the same layer, the second upper warp yarns and the second lower warp yarns to simultaneously form partial portions of the first branch tube body, the closed portion and partial portions of the second branch tube body, and the closed portion is located in the transition region where partial portions of the first branch tube body are connected to partial portions of the second branch tube body; The warp yarns of the same layer are restored to another part of the upper warp yarns and another part of the lower warp yarns, and another part of the upper warp yarns are divided into third upper warp yarns and fourth upper warp yarns, and another part of the lower warp yarns are divided into third lower warp yarns and fourth lower warp yarns; The weft yarns are respectively woven together with the first upper warp yarns, the first lower warp yarns, the third upper warp yarns and the third lower warp yarns to form the remaining portion of the first branch tube body, and the weft yarns are respectively used with the second upper warp yarns, the second lower warp yarns, the fourth upper warp yarns and the fourth lower warp yarns to weave the remaining portion of the second branch tube body, thereby obtaining the complete first branch tube body and the second branch tube body.

14. A covered stent, characterized in that, It includes the tubular film-covered structure according to any one of claims 1-11 or the tubular film-covered structure according to any one of claims 12-13, and a stent body, and the tubular film-covered structure is coated on the outer surface of the stent body.

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