Coated stent

Abstract

The application discloses a coated stent. The coated stent comprises a supporting framework and a degradable coated structure, the supporting framework is an elastic net structure, the coated structure comprises a wrapping piece and an elastic closed film piece, the wrapping piece is coated on the net wire of the supporting framework, and the elastic closed film piece is connected in each mesh of the supporting framework respectively, and the elastic closed film piece is used for closing the corresponding mesh. After the coated stent is implanted in a blood vessel, when the coated structure is degraded and absorbed, the vascular endothelium can carry out normal endothelialization process, in the treatment of vascular stenosis operation process, the coated stent can easily pass through the stenosis part of the blood vessel, and the risk of thrombosis in the coated stent and edge stenosis of the coated stent is reduced. The degradable coated structure made of biodegradable material is used for temporarily plugging the perforation, and the coated structure is degraded by the human body after a long time, so that the vascular restenosis is avoided, and the risk of vascular intimal hyperplasia is reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of medical devices, in particular to a coated stent. BACKGROUND

[0002] In order to reduce the trauma caused by surgery, intravascular intervention treatment of coronary artery gradually becomes an important means for treating coronary atherosclerosis. Intravascular intervention treatment has the advantages of less time consumption, less trauma, fewer complications, less pain for patients and good tolerance for elderly patients. However, the blood vessel may be damaged by the instruments such as guide wire and catheter during the operation process to cause perforation. For the blood vessel perforation, the commonly used treatment method is to use a covered stent. The covered stent, also known as a membrane stent, is composed of a stent and a thin layer of film. It is an artificial in-vivo implant with part or complete coverage of the inner or outer surface of the bare tubular stent with film material. The covered stent uses the support function of the stent and the covering function of the film to close the ruptured or perforated blood vessel. The covered stent not only retains the support function of the ordinary stent to effectively improve the abnormal hemodynamics of the diseased blood vessel, but also has the characteristics of the film material to cover the damaged part of the blood vessel.

[0003] The conventional covered stent cannot allow endothelial cells to pass through the stent mesh for normal stent endothelialization process when in use. Therefore, the patient implanted with the covered stent usually needs to take double anti-platelet drugs for life. At present, the covered stent has been improved. For example, the JOSTENT GraftMaster preloaded membrane stent system has been used in clinical coronary artery treatment. However, this system still has many shortcomings, for example, ① due to the use of double-layer tubular stent and ePTFE sandwich design, the total thickness is as high as 0.3 mm, and the flexibility and passability are poor. Generally, it is not suitable for treating distal vessel perforation or perforation with a diameter of <2.75 mm. When there is severe calcification, severe distortion or a covered stent has been placed in the proximal segment of the perforation, it is often difficult to deliver a new covered stent to the perforation site. ② It cannot proceed with the stent vascular endothelialization process, which may increase the risk of stent thrombosis. ③ The restenosis rate of the blood vessel after the placement of the covered stent is as high as 31.6%, and most of them are located at the edge of the covered stent, with an incidence of 29.8%. SUMMARY

[0004] Therefore, it is necessary to provide a coated stent. The coated stent of the present application can realize normal endothelialization process of the vascular endothelium after implantation, easily pass through the stenosis part of the blood vessel during the treatment of vascular stenosis, and reduce the risk of thrombosis in the coated stent and stenosis at the edge of the coated stent.

[0005] The film-coated stent comprises a support framework and a degradable film-coated structure, the support framework is an elastic net structure, the film-coated structure comprises a wrapping piece and an elastic closed film piece, the wrapping piece is coated on the wire of the support framework, and the elastic closed film piece is connected in each mesh of the support framework respectively, and the elastic closed film piece is used for closing the corresponding mesh.

[0006] In one of the embodiments, the wrapping piece and the elastic closed film piece are connected in an integrated structure.

[0007] In one of the embodiments, the preparation material of the support framework is a flexible metal.

[0008] In one of the embodiments, the preparation materials of the wrapping piece and the elastic closed film piece are the same.

[0009] In one of the embodiments, the breaking elongation of the preparation material of the film-coated structure is not less than 500%.

[0010] In one of the embodiments, the preparation material of the film-coated structure is selected from one or more of polyethylene glycol citrate, polyethylene glycol succinate citrate and aliphatic polyester.

[0011] In one of the embodiments, the support framework comprises a plurality of framework wires, the framework wires are in a wave shape, a plurality of the framework wires are sequentially distributed along a circumferential direction, along the clockwise or counterclockwise direction of the circumference, the peak part of the Nth framework wire is connected with the valley part of the N+1th framework wire through the connecting wire, and the Nth framework wire and the N+1th framework wire are separated by the connecting wire to form a plurality of meshes, wherein N is an integer greater than or equal to 1.

[0012] In one of the embodiments, the mesh is in an irregular hexagonal structure.

[0013] In one of the embodiments, the thickness of the support framework is 70-80 mu m.

[0014] In one of the embodiments, the thickness of the wrapping piece is 10-20 mu m.

[0015] The film-coated stent of the present application can promote normal endothelialization process of the vascular endothelium after the film-coated structure is degraded and absorbed after being implanted in the blood vessel, can easily pass through the stenosis part of the blood vessel during the treatment of vascular stenosis, and can reduce the risk of thrombosis in the film-coated stent and the stenosis of the edge of the film-coated stent.

[0016] The coated stent of the present invention has a coating structure wrapped around the mesh of the support frame, with elastic sealing membrane members sealingly connected between the meshes. When the support frame is collapsed, the elastic sealing membrane members can be retracted within the meshes. When the support frame is expanded, the elastic sealing membrane members can expand and form a film layer within the meshes. The coating structure of the present invention is degradable and can be degraded and absorbed by biological tissue. After the coating structure is completely degraded, the vascular endothelium can normally complete the stent endothelialization process, avoiding lifelong dual antiplatelet drug treatment, effectively preventing thrombosis within the coated stent, and also preventing restenosis at the edges of the coated stent, maintaining normal blood circulation. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a schematic diagram of the side structure of the coating bracket according to one embodiment of the present invention;

[0018] Figure 2 for Figure 1 The AA cross-sectional view of the coated bracket in the unfolded state is shown;

[0019] Figure 3 for Figure 1 The AA cross-sectional view of the coating bracket in the gathered state is shown;

[0020] Figure 4 for Figure 1 The schematic diagram of the radial surface of the coated stent in the gathered state is shown;

[0021] Figure 5 for Figure 4 The schematic diagram of the radial surface of the coated stent in the expanded state is shown.

[0022] Description of Reference Numerals

[0023] 10. Coating bracket; 100. Support frame; 110. Skeleton wire; 111. Peak part; 112. Valley part; 113. Mesh wire; 114. Mesh; 120. Connecting wire; 200. Coating structure; 210. Wrapping part; 220. Elastic sealing membrane part. DETAILED DESCRIPTION

[0024] To facilitate understanding of the present invention, the present invention will be described more fully below with reference to the accompanying drawings. Preferred embodiments of the present invention are shown in the accompanying drawings. However, the present invention may be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and comprehensive understanding of the present disclosure.

[0025] In the description of the present application, it should be understood that the terms "center", "upper", "lower", "bottom", "inner", "outer" and the like used in the description of the present application indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the purpose of facilitating the description of the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation of the present application.

[0026] It should be understood that the terms "first", "second" and the like are used in the present application to describe various information, but these information should not be limited to these terms, and these terms are only used to distinguish the same type of information from each other. For example, the "first" information can also be referred to as "second" information, and similarly, the "second" information can also be referred to as "first" information without departing from the scope of the present application.

[0027] In the description of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "connected", "connected" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium, it can be the internal communication of two elements, that is, when an element is referred to as "fixed to" another element, it can be directly on another element or there can be a middle element. When an element is considered to be "connected" to another element, it can be directly connected to another element or there can be a middle element. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0028] 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 to which the present application belongs. The terms used in the specification of the present application herein are only for the purpose of describing the specific embodiments and are not intended to limit the present application. The term "and / or" used herein includes any and all combinations of one or more related listed items.

[0029] Referring to Figure 1 An embodiment of the present application provides a coating support 10.

[0030] A coating support 10 includes a support framework 100 and a degradable coating structure 200.

[0031] Referring to Figure 1As shown, the support framework 100 is an elastic net structure, the film coating structure 200 comprises a wrapping piece 210 and an elastic sealing film piece 220, the net wire 113 of the support framework 100 is coated with the wrapping piece 210, and each mesh hole 114 of the support framework 100 is connected with the elastic sealing film piece 220 respectively, and the elastic sealing film piece 220 is used for sealing the corresponding mesh hole 114.

[0032] In one embodiment, the wrapping piece 210 is connected with the elastic sealing film piece 220 in an integrated structure, and the wrapping piece 210 and the elastic sealing film piece 220 are made of the same material. In the preparation, the material of the support framework 100 can be a flexible metal, and an elastic polyester material that can be biodegraded and absorbed is plated on the net wire 113 of the support framework 100 by immersion process to form the film coating structure 200 wrapping the support framework 100.

[0033] The support framework 100 of the film coating stent 10 has two forms: in the delivery, the support framework 100 is in the condensed state, and at this time, the elastic sealing film piece 220 is in the condensed state, please refer to Figure 3 As shown; when the film coating stent 10 reaches the blood vessel injury site, the support framework 100 is converted to the expanded state by the balloon expansion, and at this time, the elastic sealing film piece 220 is in the expanded state, please refer to Figure 2 As shown. The expanded state is an expandable fixed shape structure, and the diameter of the support framework 100 in the expanded state is greater than the diameter of the support framework 100 in the condensed state, please refer to Figure 4 and Figure 5 After the support framework 100 is expanded, the elastic sealing film piece 220 on the mesh hole 114 of the support framework 100 is stretched and stretched to form a film layer for covering the blood vessel injury site.

[0034] In one embodiment, the material of the support framework 100 is a flexible metal, for example, the material of the support framework 100 is a memory alloy.

[0035] In one embodiment, the breaking elongation of the material of the film coating structure 200 is not less than 500%.

[0036] In one embodiment, the material of the film coating structure 200 is selected from one or more of poly(lactic-co-glycolic acid), poly(lactic acid) and poly(glycolic acid). The preparation method of the above-mentioned materials is as follows: poly(lactic-co-glycolic acid) is prepared by melt polycondensation with lactic acid and glycolic acid as monomers. Glycol reacts with succinic acid to obtain small molecular polyester diol, and then the small molecular polyester diol reacts with lactic acid to prepare degradable elastomer poly(lactic-co-glycolic acid); decanedioic acid, ethylene glycol and glycerol are used as raw materials to synthesize degradable aliphatic polyester.

[0037] In one embodiment, the support skeleton 100 comprises a plurality of skeleton wires 110 and connecting wires 120. The skeleton wires 110 are wavy, and the plurality of skeleton wires 110 are sequentially distributed along a circumferential direction. Along the circumferential direction, the peak portion of the Nth skeleton wire 110 is connected to the valley portion of the N+1th skeleton wire 110 through the connecting wire 120, and the Nth skeleton wire 110 and the N+1th skeleton wire 110 are separated by the connecting wire 120 to form a plurality of mesh holes 114, where N is an integer greater than or equal to 1, for example, N is 1, 2, 3, 4, etc., and the maximum value of N = the number of skeleton wires 110 - 1. The skeleton wires 110 and the connecting wires 120 can be connected by welding.

[0038] In one embodiment, the mesh hole 114 has an irregular hexagonal structure.

[0039] In one embodiment, the thickness of the support skeleton 100 is 70-80 μm. It should be noted that the thickness of the support skeleton 100 refers to the thickness T between the inner wall and the outer wall of the support skeleton 100 along the radial direction, as shown in Figure 4 For example, in one specific embodiment, the thickness of the support skeleton 100 is 70 μm, and in another specific embodiment, the thickness of the support skeleton 100 is 80 μm. It is not difficult to understand that in other embodiments, the thickness of the support skeleton 100 can also be 75 μm or other values.

[0040] In one embodiment, the radial cross-section of the mesh wire 113 can be wedge-shaped, elliptical, circular, square, etc. Preferably, referring to FIG. 1, the radial cross-section of the mesh wire 113 is wedge-shaped.

[0041] In one embodiment, the thickness of the wrapping member 210 is 10-20 μm. For example, in one specific embodiment, the thickness of the wrapping member 210 is 10 μm, and in another specific embodiment, the thickness of the wrapping member 210 is 20 μm. It is not difficult to understand that the thickness of the wrapping member 210 can also be 11 μm, 12 μm, 13 μm, 15 μm, 17 μm, 18 μm or other values.

[0042] The coated stent 10 of the present application, after the coated structure 200 is degraded and absorbed after being implanted in the blood vessel, the endothelium of the blood vessel can proceed with normal endothelialization process, and in the process of treating vascular stenosis, it is easy to pass through the stenosis of the blood vessel, reducing the risk of thrombosis in the coated stent 10 and the edge stenosis of the coated stent 10. The coated structure 200 made of biodegradable material is used to temporarily block the perforation, and after a long time, it is degraded by the human body and does not cause restenosis of the blood vessel, reducing the risk of intimal hyperplasia.

[0043] The coating stent 10 of the present application, the wrapping part 210 of the coating structure 200 is wrapped around the mesh wire 113 of the support framework 100, and the elastic sealing film part 220 is sealingly connected between the mesh holes 114. When the support framework 100 is folded, the elastic sealing film part 220 can be folded into the mesh hole 114, and when the support framework 100 is unfolded, the elastic sealing film part 220 can be unfolded and form a film layer in the mesh hole 114. The coating structure 200 in the present application can be degraded and can be degraded and absorbed by biological tissues. After the coating structure 200 is completely degraded, the vascular endothelium can normally complete the stent endothelialization process, avoid lifelong dual antiplatelet drug therapy, effectively avoid thrombosis in the coating stent 10, and also avoid edge restenosis of the coating stent 10, and maintain normal blood circulation.

[0044] Embodiment 1

[0045] The present embodiment provides a coating stent 10.

[0046] Referring to Figures 1-3 The coating stent 10 includes a support framework 100 and a degradable coating structure 200.

[0047] The support framework 100 is an elastic mesh structure. The support framework 100 is made of a memory alloy.

[0048] The support framework 100 includes a plurality of framework wires 110 and connecting wires 120. The framework wire 110 is in a wave shape, and the plurality of framework wires 110 are sequentially distributed along the circumferential direction. Along the clockwise or counterclockwise direction of the circumference, the peak part of the Nth framework wire 110 is connected to the valley part of the N+1th framework wire 110 through the connecting wire 120, and the Nth framework wire 110 and the N+1th framework wire 110 are separated by the connecting wire 120 to form a plurality of mesh holes 114, wherein N is an integer greater than or equal to 1. The framework wire 110 and the connecting wire 120 can be connected by welding. The mesh hole 114 is in an irregular hexagonal structure.

[0049] The thickness of the support framework 100 is 70 μm.

[0050] The coating structure 200 includes a wrapping part 210 and an elastic sealing film part 220. The wrapping part 210 is coated on the mesh wire 113 of the support framework 100, and the thickness of the wrapping part 210 is 10 μm.

[0051] Each mesh hole 114 of the support framework 100 is connected with an elastic sealing film part 220, and the elastic sealing film part 220 is used to seal the corresponding mesh hole 114.

[0052] The wrapping piece 210 is connected with the elastic sealing film piece 220 in an integrated structure, and the wrapping piece 210 and the elastic sealing film piece 220 are made of the same material. The preparation material of the film-coated structure 200 is selected from poly(lactic acid-co-glycolic acid). The preparation material of the film-coated structure 200 has an elongation at break of 500%. The preparation method of the above material is as follows: polyethylene glycol and lactic acid are monomers, and a biodegradable elastomer poly(lactic acid-co-glycolic acid) is prepared by melt polycondensation.

[0053] Embodiment 2

[0054] The embodiment provides a film-coated stent 10.

[0055] Referring to Figures 1-3 Fig. 1 shows a film-coated stent 10, which comprises a support framework 100 and a degradable film-coated structure 200.

[0056] The support framework 100 is an elastic net structure. The support framework 100 is made of a memory alloy.

[0057] The support framework 100 comprises a plurality of framework wires 110 and connecting wires 120. The framework wires 110 are in a wave shape, and the plurality of framework wires 110 are sequentially distributed along a circumferential direction. Along the clockwise or counterclockwise direction of the circumference, the peak part of the Nth framework wire 110 is connected to the valley part of the N+1th framework wire 110 through the connecting wire 120, and the Nth framework wire 110 and the N+1th framework wire 110 are separated by the connecting wire 120 to form a plurality of mesh holes 114, where N is an integer greater than or equal to 1. The framework wire 110 and the connecting wire 120 can be connected by welding. The mesh hole 114 is in an irregular hexagonal structure.

[0058] The thickness of the support framework 100 is 80 μm.

[0059] The film-coated structure 200 comprises a wrapping piece 210 and an elastic sealing film piece 220, and the wrapping piece 210 is coated on the mesh wire 113 of the support framework 100. The thickness of the wrapping piece 210 is 20 μm.

[0060] Each mesh hole 114 of the support framework 100 is connected with the elastic sealing film piece 220, and the elastic sealing film piece 220 is used for sealing the corresponding mesh hole 114.

[0061] The wrapping piece 210 is connected with the elastic sealing film piece 220 in an integrated structure, and the wrapping piece 210 and the elastic sealing film piece 220 are made of the same material. The preparation material of the film-coated structure 200 is selected from poly(lactic acid-co-glycolic acid). The preparation material of the film-coated structure 200 has an elongation at break of 500%. The preparation method of the above material is as follows: polyethylene glycol and lactic acid are monomers, and a biodegradable elastomer poly(lactic acid-co-glycolic acid) is prepared by melt polycondensation.

[0062] Embodiment 3

[0063] The embodiment provides a coated stent 10.

[0064] Referring to Figures 1-3 As shown in the figure, the coated stent 10 comprises a support framework 100 and a degradable coated structure 200.

[0065] The support framework 100 is an elastic net structure. The support framework 100 is made of a memory alloy.

[0066] The support framework 100 comprises a plurality of framework wires 110 and connecting wires 120. The framework wires 110 are in a wave shape, and the plurality of framework wires 110 are sequentially distributed along a circumferential direction. Along the clockwise or counterclockwise direction of the circumference, the peak part of the Nth framework wire 110 is connected to the valley part of the N+1th framework wire 110 through the connecting wire 120, and the Nth framework wire 110 and the N+1th framework wire 110 are separated by the connecting wire 120 to form a plurality of mesh holes 114, wherein N is an integer greater than or equal to 1. The framework wire 110 and the connecting wire 120 can be connected by welding. The mesh hole 114 is in an irregular hexagonal structure.

[0067] The thickness of the support framework 100 is 75 μm.

[0068] The coated structure 200 comprises a wrapping piece 210 and an elastic sealing film piece 220. The wrapping piece 210 is coated on the mesh wire 113 of the support framework 100, and the thickness of the wrapping piece 210 is 15 μm.

[0069] The elastic sealing film piece 220 is connected in each mesh hole 114 of the support framework 100, and the elastic sealing film piece 220 is used for sealing the corresponding mesh hole 114.

[0070] The wrapping piece 210 and the elastic sealing film piece 220 are connected in an integral structure, and the wrapping piece 210 and the elastic sealing film piece 220 are made of the same material. The material of the coated structure 200 is selected from poly(lactic acid-co-glycolic acid). The breaking elongation of the material of the coated structure 200 is 500%. The material is prepared by the following method: polyethylene glycol and lactic acid are monomers, and a biodegradable elastomer poly(lactic acid-co-glycolic acid) is prepared by melt polycondensation.

[0071] Embodiment 4

[0072] The embodiment provides a coated stent 10.

[0073] Referring to Figures 1-3 As shown in the figure, the coated stent 10 comprises a support framework 100 and a degradable coated structure 200.

[0074] The support framework 100 is an elastic net structure. The support framework 100 is made of a memory alloy.

[0075] The support framework 100 includes a plurality of framework wires 110 and connecting wires 120. The framework wires 110 are wavy, and the plurality of framework wires 110 are sequentially distributed along a circumferential direction. Along the circumferential direction, a peak portion on an Nth framework wire 110 is connected to a valley portion on an N+1th framework wire 110 through a connecting wire 120, and the Nth framework wire 110 and the N+1th framework wire 110 are separated by the connecting wire 120 to form a plurality of mesh holes 114, where N is an integer greater than or equal to 1. The framework wires 110 and the connecting wires 120 can be connected by welding. The mesh holes 114 are irregular hexagonal structures.

[0076] The thickness of the support framework 100 is 75 μm.

[0077] The coating structure 200 includes a wrapping piece 210 and an elastic sealing film piece 220. The wrapping piece 210 is coated on the mesh wire 113 of the support framework 100, and the thickness of the wrapping piece 210 is 15 μm.

[0078] Each mesh hole 114 of the support framework 100 is connected with an elastic sealing film piece 220, and the elastic sealing film piece 220 is used to seal the corresponding mesh hole 114.

[0079] The wrapping piece 210 and the elastic sealing film piece 220 are connected in an integral structure, and the wrapping piece 210 and the elastic sealing film piece 220 are made of the same material. The coating structure 200 is made of polyethylene glycol succinate citrate. The breaking elongation of the material of the coating structure 200 is 600%. The material is prepared as follows: ethylene glycol is reacted with succinic acid to obtain small molecule polyester diol, and then the small molecule polyester diol is reacted with citric acid to prepare a degradable elastomer, polyethylene glycol succinate citrate.

[0080] Example 5

[0081] This embodiment provides a coated stent 10.

[0082] Referring to Figures 1-3 , a coated stent 10 includes a support framework 100 and a degradable coating structure 200.

[0083] The support framework 100 is an elastic net structure. The support framework 100 is made of a memory alloy.

[0084] The support framework 100 comprises a plurality of framework wires 110 and connecting wires 120. The framework wires 110 are wavy, and the plurality of framework wires 110 are sequentially distributed along a circumferential direction. The peak portion of the Nth framework wire 110 is connected to the valley portion of the N+1th framework wire 110 through the connecting wire 120 along the clockwise or counterclockwise direction of the circumference. The Nth framework wire 110 and the N+1th framework wire 110 are separated by the connecting wire 120 to form a plurality of mesh holes 114, where N is an integer greater than or equal to 1. The framework wires 110 and the connecting wires 120 can be connected by welding. The mesh holes 114 have an irregular hexagonal structure.

[0085] The thickness of the support framework 100 is 70 μm.

[0086] The coating structure 200 comprises a wrapping member 210 and an elastic sealing film member 220. The wrapping member 210 is coated on the mesh wire 113 of the support framework 100, and the thickness of the wrapping member 210 is 15 μm.

[0087] Each mesh hole 114 of the support framework 100 is connected with an elastic sealing film member 220, and the elastic sealing film member 220 is used to seal the corresponding mesh hole 114.

[0088] The wrapping member 210 and the elastic sealing film member 220 are connected in an integral structure, and the preparation materials of the wrapping member 210 and the elastic sealing film member 220 are the same. The preparation material of the coating structure 200 is selected from aliphatic polyester. The breaking elongation of the preparation material of the coating structure 200 is 600%. The above-mentioned material is synthesized by using sebacic acid, ethylene glycol and glycerol as raw materials.

[0089] Example 6

[0090] The embodiment provides a coated stent 10.

[0091] Referring to Figures 1-3 , a coated stent 10 comprises a support framework 100 and a degradable coating structure 200.

[0092] The support framework 100 is an elastic mesh structure. The preparation material of the support framework 100 is a memory alloy.

[0093] The support framework 100 comprises a plurality of framework wires 110 and connecting wires 120. The framework wires 110 are wavy, and the plurality of framework wires 110 are sequentially distributed along a circumferential direction. The peak portion of the Nth framework wire 110 is connected to the valley portion of the N+1th framework wire 110 through the connecting wire 120 along the clockwise or counterclockwise direction of the circumference, and the Nth framework wire 110 and the N+1th framework wire 110 are separated by the connecting wire 120 to form a plurality of mesh holes 114, where N is an integer greater than or equal to 1. The framework wires 110 and the connecting wires 120 can be connected by welding. The mesh holes 114 are irregular hexagonal structures.

[0094] The thickness of the support framework 100 is 80 μm.

[0095] The coating structure 200 comprises a wrapping member 210 and an elastic sealing film member 220. The wrapping member 210 is coated on the mesh wire 113 of the support framework 100, and the thickness of the wrapping member 210 is 15 μm.

[0096] The elastic sealing film member 220 is connected in each mesh hole 114 of the support framework 100, and the elastic sealing film member 220 is used to seal the corresponding mesh hole 114.

[0097] The wrapping member 210 and the elastic sealing film member 220 are connected in an integral structure. The wrapping member 210 is made of poly(lactic acid-co-glycolic acid). The elastic sealing film member 220 is made of aliphatic polyester. The breaking elongation of the material of the elastic sealing film member 220 is 600%. The preparation method of the poly(lactic acid-co-glycolic acid) is as follows: polyethylene glycol and lactic acid are monomers, and the biodegradable elastomer poly(lactic acid-co-glycolic acid) is prepared by melt polycondensation. The preparation method of the aliphatic polyester material is as follows: sebacic acid, ethylene glycol, and glycerol are raw materials for synthesizing degradable aliphatic polyester.

[0098] Example 7

[0099] The embodiment provides a coated stent 10.

[0100] Referring to Figures 1-3 The coated stent 10 comprises a support framework 100 and a degradable coating structure 200.

[0101] The support framework 100 is an elastic mesh structure. The support framework 100 is made of a memory alloy.

[0102] The support framework 100 comprises a plurality of framework wires 110 and connecting wires 120. The framework wires 110 are wavy, and the plurality of framework wires 110 are sequentially distributed along a circumferential direction. The peak portion of the Nth framework wire 110 is connected to the valley portion of the N+1th framework wire 110 through the connecting wire 120 along the clockwise or counterclockwise direction of the circumference, and the Nth framework wire 110 and the N+1th framework wire 110 are separated by the connecting wire 120 to form a plurality of mesh holes 114, wherein N is an integer greater than or equal to 1. The framework wire 110 and the connecting wire 120 can be connected by welding. The mesh hole 114 has an irregular hexagonal structure.

[0103] The thickness of the support framework 100 is 70 μm.

[0104] The coating structure 200 comprises a wrapping piece 210 and an elastic sealing film piece 220. The wrapping piece 210 is coated on the mesh wire 113 of the support framework 100, and the thickness of the wrapping piece 210 is 15 μm.

[0105] Each mesh hole 114 of the support framework 100 is connected with an elastic sealing film piece 220, and the elastic sealing film piece 220 is used to seal the corresponding mesh hole 114.

[0106] The wrapping piece 210 and the elastic sealing film piece 220 are connected in an integral structure. The wrapping piece 210 is made of polyethylene glycol succinate citrate. The elastic sealing film piece 220 is made of aliphatic polyester. The breaking elongation of the material of the elastic sealing film piece 220 is 600%. The preparation method of the polyethylene glycol succinate citrate is as follows: ethylene glycol is reacted with succinic acid to obtain small molecular polyester diol, and then the small molecular polyester diol is reacted with citric acid to prepare the degradable elastomer polyethylene glycol succinate citrate. The preparation method of the aliphatic polyester material is as follows: decanedioic acid, ethylene glycol and glycerol are used as raw materials to synthesize the degradable aliphatic polyester.

[0107] Any combination of the technical features of the above-described embodiments can be made. In order to make the description simple, all possible combinations of the technical features in the above-described embodiments are not described, however, as long as the combination of the technical features does not exist, it should be considered as the scope of the description.

[0108] The above-described embodiments only express several embodiments of the present application, and the description is more specific and detailed, but it cannot be understood as a limitation on the scope of the patent of the present application. It should be noted that for ordinary skilled persons in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are within the scope of protection of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims.

Claims

1. A coating support, characterized by, The support framework is an elastic net structure, and the support framework comprises a plurality of framework filaments and connecting filaments, the framework filaments are in a wavy shape, the plurality of framework filaments are sequentially distributed along a circumferential direction, along the clockwise or counterclockwise direction of the circumference, the peak part of the Nth framework filament is connected to the valley part of the N+1th framework filament through the connecting filament, the Nth framework filament and the N+1th framework filament are separated by the connecting filament to form a plurality of mesh holes, the mesh holes are in an irregular hexagonal structure, wherein N is an integer greater than or equal to 1, the coating structure comprises a wrapping piece and an elastic sealing film piece, the wrapping piece is coated on the mesh wire of the support framework, and the elastic sealing film piece is connected in each mesh hole of the support framework, respectively, the edge of the elastic sealing film piece is connected to the wrapping piece on the corresponding mesh wire in an integral structure, the elastic sealing film piece is used for sealing the corresponding mesh hole, the preparation material of the wrapping piece is selected from polyglycolic acid polyethylene glycol or polyethylene glycol succinate citrate, the preparation material of the elastic sealing film piece is selected from aliphatic polyester, and the breaking elongation of the preparation material of the coating structure is not less than 500%.

2. The coated stent of claim 1, wherein, The preparation material of the support framework is a flexible metal.

3. The coated stent according to any of claims 1-2, wherein, The thickness of the support framework is 70-80 mu m.

4. The coated stent of any of claims 1-2, wherein, The thickness of the wrapping piece is 10-20 mu m.

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