A coated vascular stent with improved wall adhesion performance

Abstract

The present invention provides a coated vascular stent with improved wall adhesion performance, which includes a coating and a main support frame arranged on the coating. The coated vascular stent also includes an expansion positioning piece arranged at the proximal end and / or distal end of the coating. After the coated vascular stent is subjected to radial compression, the radial supporting force of the expansion positioning piece can maintain the complete expansion of the proximal end and / or distal end of the coating, so that the coated vascular stent is sealed and fitted with the inner wall of the blood vessel to avoid internal leakage.

Description

Technical Field

[0001] The present invention relates to the field of implantable blood vessel technology, and in particular to a coated vascular stent with improved wall adhesion performance. The coated vascular stent is delivered to a vascular lesion site through a delivery catheter by percutaneous puncture, and the vascular stent is released at the vascular lesion site and expanded to form a vascular cavity, thereby playing a role in reshaping the blood vessel. Background Art

[0002] At present, minimally invasive interventional procedures can be used to treat vascular diseases. This method is less traumatic to patients, highly safe, and highly effective. Therefore, it is recognized by doctors and patients and has become an important treatment method for vascular diseases. Interventional treatment refers to the use of a delivery system to implant a vascular stent into the patient's vascular disease segment. The implanted vascular stent can expand to support the narrowed and occluded segment of the blood vessel or block the rupture of the vascular dissection, reduce the elastic retraction and reshaping of the blood vessel, maintain smooth blood flow in the lumen, and also has the effect of preventing restenosis.

[0003] The coated vascular stent is a widely used vascular stent that can isolate blood flow and diseased blood vessels, thereby eliminating the fatal risk of blood vessel rupture. However, existing coated vascular stents have the disadvantage of endoleak, which refers to the phenomenon of continuous blood flow outside the coated vascular stent cavity and in the aneurysm cavity and adjacent blood vessel cavity treated by the coated vascular stent after the coated vascular stent is placed in the blood vessel. Consequences of endoleak: (1) The aneurysm cavity continues to enlarge, eventually causing the aortic aneurysm to rupture or turn to traditional surgery. (2) Thrombus in the aneurysm cavity is squeezed into the normal blood flow, causing distal arterial embolism.

[0004] Endoleak is divided into four types according to the source of bleeding: Endoleak is caused by the inability of the covered vascular stent to fit tightly with the native blood vessel, including the proximal and distal interfaces; bleeding comes from the backflow of blood from the collateral vessels, including the lumbar artery, inferior mesenteric artery, middle sacral artery, internal iliac artery, etc.; Endoleak is caused by the inability of the covered vascular stent interface to fit tightly or the covered vascular stent ruptures; leakage is caused by the gaps in the covered woven film of the stent. Among them, the common causes of endoleak caused by the inability of the covered vascular stent to fit tightly with the native blood vessel are: (1) Vascular angulation: The continuous expansion of the aneurysm, the change of the arterial wall structure and the hemodynamic changes cause the blood vessel to twist. This twist often occurs in the proximal neck vessels and iliac arteries of the aneurysm. When the stent anchoring site is in the proximal and distal vascular angulation area, the vascular angulation may cause the stent to be unable to fit tightly with the blood vessel after placement. The larger the angle, the more likely it is to cause bleeding. (2) Too short aneurysm neck: Too short a proximal aneurysm neck causes the stent to be unable to fit tightly with the native blood vessel, which is another important cause of proximal endoleak. (3) Neck vascular morphology: The uniform thickness of the proximal neck vessels is very important for the firm anchoring of the coated vascular stent. (4) Vascular calcification: Calcification is a common pathological change in aneurysms. When calcified plaques are located in the anchoring area of ​​the coated vascular stent, the stent may not fit tightly with the native blood vessel. (5) Wrong selection of the diameter of the coated vascular stent: When the diameter of the stent at the proximal and distal anchoring sites is too small, endoleak may occur. (6) Reshaping of the coated vascular stent: Reshaping of the coated vascular stent within a certain period of time after implantation is an important factor in the occurrence of secondary endoleak. Insufficient anchoring of the coated vascular stent results in poor stability of the coated vascular stent after placement, which is the main cause of endoleak after reshaping. The above factors often exist at the same time. At present, the general method for treating endoleak is balloon dilatation or the addition of stent-type blood vessels; however, the current treatment methods still cannot completely eliminate endoleak. Summary of the invention

[0005] The object of the present invention is to provide a coated vascular stent which can improve the wall adhesion performance and eliminate the internal leakage.

[0006] In order to solve the above technical problems, the present invention provides a coated vascular stent with improved wall adhesion performance, which includes a coating, a main support frame arranged on the coating, and an expansion positioning piece arranged at the proximal end and / or distal end of the coating. After the coated vascular stent is subjected to radial compression, the radial supporting force of the expansion positioning piece can maintain the complete expansion of the proximal end and / or distal end of the coating.

[0007] The coated vascular stent provided by the present invention is provided with the expansion positioning piece at the proximal end and / or the distal end of the coating, and the expansion positioning piece has a radial supporting force. Therefore, when the coated vascular stent is deployed in the implanted blood vessel, the radial supporting force of the expansion positioning piece can expand the proximal end and / or the distal end of the coating to fit the inner wall of the blood vessel, so as to maintain the sealing fit between the proximal end and / or the distal end of the coating and the inner wall of the blood vessel, so that there is no gap between the coating and the inner wall of the blood vessel, thereby avoiding internal leakage. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] In order to more clearly illustrate the technical solution of the embodiment of the present invention, the drawings required for use in the implementation mode will be briefly introduced below. Obviously, the drawings described below are some implementation modes of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0009] Figure 1 It is a schematic structural diagram of the coated vascular stent provided in the first embodiment of the present invention.

[0010] Figure 2 yes Figure 1 An enlarged view of part II in FIG.

[0011] Figure 3 It is a schematic diagram of the structure of a coated vascular stent provided in the second embodiment of the present invention.

[0012] Figure 4 It is a schematic structural diagram of a coated vascular stent provided in the third embodiment of the present invention.

[0013] Figure 5 yes Figure 4 Magnified view of section V in FIG.

[0014] Figure 6 yes Figure 4 An enlarged view of section VI in FIG.

[0015] Figure 7 It is a schematic structural diagram of a coated vascular stent provided in the fourth embodiment of the present invention.

[0016] Figure 8 yes Figure 7 An enlarged view of section VIII in FIG.

[0017] Fig. 9 It is a schematic structural diagram of a coated vascular stent provided in the fifth embodiment of the present invention.

[0018] Fig.10 It is a schematic diagram of the structure of a coated vascular stent provided in the sixth embodiment of the present invention.

[0019] Fig.11 It is a schematic structural diagram of a coated vascular stent provided in the seventh embodiment of the present invention.

[0020] Fig.12 yes Fig.11 An enlarged view of section XII in FIG.

[0021] Fig.13 It is a schematic structural diagram of a coated vascular stent provided in the eighth embodiment of the present invention.

[0022] Fig.14 yes Fig.13 Magnified view of section XIV in .

[0023] Fig.15 It is a schematic structural diagram of a coated vascular stent provided in the ninth embodiment of the present invention.

[0024] Fig.16 yes Fig.15 An enlarged view of section XVI in FIG. DETAILED DESCRIPTION

[0025] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0026] In addition, the following descriptions of the embodiments are with reference to the attached drawings to illustrate specific embodiments in which the present invention may be implemented. The directional terms mentioned in the present invention, such as "upper", "lower", "front", "back", "left", "right", "inner", "outer", "side", etc., are only with reference to the directions of the attached drawings. Therefore, the directional terms used are for better and clearer description and understanding of the present invention, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention.

[0027] In the description of the present invention, the "proximal end" of the present invention refers to the end close to the heart, and the "distal end" refers to the end far from the heart. The high and low mentioned in the present invention are relative to the coating. The end surface beyond the coating is called high, and the end surface not beyond the coating is called low. This definition is only for the convenience of expression and cannot be understood as a limitation of the present invention.

[0028] See also Figure 1 and Figure 2 , Figure 1 is a schematic structural diagram of a coated vascular stent provided in a first embodiment of the present invention; Figure 2 yes Figure 1 An enlarged view of part II in the figure. The present invention provides a coated vascular stent 100 with improved wall adhesion performance, which includes a tubular coating 20, a main support frame 40 arranged on the coating 20, and an expansion and support positioning member 60 arranged at the proximal end and / or distal end of the coating 20. After the coated vascular stent 100 is implanted in a blood vessel, that is, the membrane stent 100 is subjected to radial compression due to expansion, the radial support force of the expansion and support positioning member 60 can maintain the proximal end and / or distal end of the coating 20 to be fully expanded, so that the coating 20 is sealed and fitted with the inner wall of the blood vessel to avoid internal leakage. In this embodiment, the radial support force of the expansion and support positioning member 60 can maintain the proximal end and / or distal end of the coating 20 in a complete circular ring structure.

[0029] The expansion and support positioning member 60 is a self-expanding annular positioning frame, which can expand radially, and the coating 20 is fixed on the annular positioning frame. The annular positioning frame can be arranged at the proximal end and / or distal end of the coating 20, and the proximal end and / or distal end of the coating 20 are fixed to the outer surface and / or inner surface of the annular positioning frame. In this embodiment, the expansion and support positioning member 60 is arranged at the proximal end of the coating 20, and the proximal end surface of the coating 20 extends to the expansion and support positioning member 60, that is, at least a part of the proximal end of the coating 20 overlaps with the expansion and support positioning member 60. Preferably, the proximal end surface of the coating 20 is flush with the proximal end surface of the expansion and support positioning member 60. When the coated vascular stent 100 is deployed, the radial support force of the expansion and support positioning member 60 expands the coating 20 to fit the inner wall of the blood vessel, so that the coating 20 and the inner wall of the blood vessel are sealed to prevent internal leakage.

[0030] In other embodiments, the proximal surface of the coating 20 may be higher than the proximal surface of the expansion positioning member 60 , and the coating 20 higher than the proximal surface of the expansion positioning member 60 is folded inward or outward and then connected to the expansion positioning member 60 .

[0031] The coated vascular stent 100 provided by the present invention is provided with the expansion positioning member 60 at the proximal end and / or the distal end of the coating 20, and the expansion positioning member 60 has a radial supporting force. Therefore, when the coated vascular stent 100 is deployed in the implanted blood vessel, the radial supporting force of the expansion positioning member 60 can expand the proximal end and / or the distal end of the coating 20 to fit the inner wall of the blood vessel, so as to maintain the sealing fit between the proximal end and / or the distal end of the coating 20 and the inner wall of the blood vessel, so that there is no gap between the coating 20 and the inner wall of the blood vessel, thereby avoiding internal leakage.

[0032] The shape of the transverse end surface of the coating 20 is circular or elliptical to match the blood vessel. The coating 20 is made of polyester cloth, polytetrafluoroethylene, polyester fiber or other medical polymer materials.

[0033] The main support frame 40 is a self-expanding support frame, which can be an elastic metal support frame or an elastic non-metal support frame such as an elastic ring or a polymer material support frame. The main support frame 40 can also restore its original shape by mechanical expansion, such as balloon expansion. In this embodiment, the support frame is a nickel-titanium alloy stent. When the support frame is transported through a sheath, the diameter of the support frame can be contracted to a smaller state for transportation in the sheath; when the main support frame 40 is released in the diseased blood vessel, the main support frame 40 can automatically expand to the required shape and size, so that the main support frame 40 can be supported on the inner wall of the diseased blood vessel, and the main support frame 40 produces a radial support effect on the inner wall of the blood vessel. In this embodiment, the main support frame 40 is a bare stent woven with metal wire.

[0034] The main support frame 40 can be a radially compressed grid structure, a rod structure, a frame structure or a soft foldable structure, etc., or a grid or frame structure formed by cutting a metal tube. The metal wire can be nickel-titanium alloy, cobalt-chromium alloy, stainless steel or other metal materials with good biocompatibility, preferably superelastic shape memory alloy nickel-titanium wire, and its manufacturing process is the same as that of traditional stents, which will not be repeated here.

[0035] like Figure 1 As shown, the main support frame 40 includes a plurality of Z-shaped or sinusoidal corrugated support rods 42, which are sutured with medical sutures or attached to the inner or outer surface of the coating 20 with medical glue, or fixed between two layers of coating 20 by hot pressing, and these corrugated support rods 42 are arranged at intervals along the axial direction of the main support frame 40. Each corrugated support rod 42 can be an equal-wave support rod or a high-low wave support rod, etc. The equal-wave support rod means that the heights of the various wave crests on the corrugated support rod 42 are the same, and the heights of the various wave troughs are also the same, that is, the various wave crests and various wave troughs are respectively on the same plane. The high-low wave support rod means that the heights of the various wave crests on the corrugated support rod 42 are different, and the heights of the various wave troughs may also be different.

[0036] In this embodiment, the main support frame 40 is composed of a plurality of equi-wave support rods arranged axially at intervals, and the corrugated support rods 42 are woven from nickel-titanium wires with a diameter of 0.5 mm. The number of sine waves can be any number, and the vertical height of the corrugated support rods 42 can be any height. Each corrugated support rod 42 is sutured to the covering film 20 by sutures, and the sutures can accompany the entire main support frame 40 along the wave direction of each corrugated support rod 42. The sutures are preferably polymer sutures, and the polymer sutures can be PTFE or PET sutures.

[0037] Each corrugated support rod 42 is composed of a plurality of support units connected end to end, and each of the support units includes a crest 421, a trough 423, and a wave rod 425 connected between the crest 421 and the trough 423. Each corrugated support rod 42 can be formed by bending a superelastic nickel-titanium wire, and each corrugated support rod 42 is provided with a connecting sleeve, which connects the opposite ends of the corrugated support rod 42, that is, the opposite ends of the corrugated support rod 42 are both received in the connecting sleeve, and then the two ends of the nickel-titanium wire are fixed inside the connecting sleeve by mechanical compression or welding.

[0038] In this embodiment, the wave crests 421 between two adjacent wave-shaped support rods 42 correspond to the wave crests 421 , and the wave troughs 423 correspond to the wave troughs 423 .

[0039] In other embodiments, the corrugated support rod 42 may also be a high-low wave support rod.

[0040] The expansion and support positioning member 60 in this embodiment is an annular braided mesh 62, which is arranged at the proximal end of the coating 20, and is woven from mutually interlaced warp wires 621 and weft wires 623; the annular braided mesh 62 is woven from elastic memory alloy wires, that is, the warp wires 621 and weft wires 623 are both woven from elastic memory alloy wires. The annular braided mesh 62 includes a proximal surface 625 and a distal surface 626, and the coating 20 is fixed on the annular braided mesh 62, and the proximal surface of the coating 20 is located between the proximal surface 625 and the distal surface 626 of the annular braided mesh 62. The annular braided mesh 62 can be woven from one elastic memory alloy wire, or it can be woven from a plurality of elastic memory alloy wires, and the memory alloy wire is preferably a nickel-titanium wire. The wire diameter of the nickel-titanium wire is less than 0.1 mm.

[0041] The woven mesh of the annular woven mesh 62 can be in other shapes such as diamond, rectangle or polygon.

[0042] The annular braided mesh 62 can be connected to the inner surface or the outer surface of the covering film 20 by suturing, heat pressing or gluing, so that the annular braided mesh 62 and the covering film 20 can be tightly fixed.

[0043] In other embodiments, the proximal surface of the coating 20 may be flush with the proximal surface of the annular braided mesh 62 .

[0044] In other embodiments, the proximal surface of the coating 20 may be higher than the proximal surface of the annular braided mesh 62 , and the coating 20 higher than the proximal surface of the annular braided mesh 62 is folded inward or outward and then connected to the annular braided mesh 62 .

[0045] In other embodiments, a developing mark is provided on the proximal edge and / or the distal edge of the annular woven mesh 62, and the developing mark can be a developing wire continuously or discontinuously wound on the proximal edge and / or the distal edge of the annular woven mesh 62, or a developing part such as a dot developing mark continuously or intermittently provided on the proximal edge and / or the distal edge of the annular woven mesh 62; the developing part material can be made of a material with good X-ray opacity, strong corrosion resistance and good biocompatibility, including but not limited to gold, platinum, tantalum, osmium, rhenium, tungsten, iridium, rhodium and the like, or alloys or composites of these metals.

[0046] In other embodiments, a developing mark is disposed on the proximal edge or the distal edge of the covering film 20 .

[0047] See also Figure 3 , Figure 3 : is a schematic diagram of the structure of the coated vascular stent provided by the second embodiment of the present invention. The structure of the coated vascular stent provided by the second embodiment of the present invention is similar to that of the first embodiment, except that: in the second embodiment, both the proximal and distal ends of the coating 20 are provided with expansion positioning members 60, specifically, the proximal and distal ends of the coating 20 are respectively provided with annular braided meshes 62, the proximal end of the coating 20 is connected to the annular braided mesh 62 at the proximal end of the coating 20, and the distal end of the coating 20 is connected to the annular braided mesh 62 at the distal end of the coating 20. The proximal surface of the coating 20 is located between the proximal surface 625 and the distal surface 626 of the proximal annular braided mesh 62, and preferably the proximal surface of the coating 20 is flush with the proximal surface 625 of the proximal annular braided mesh 62; the distal surface of the coating 20 is located between the proximal surface 625 and the distal surface 626 of the distal annular braided mesh 62, and preferably the distal surface of the coating 20 is flush with the distal surface 626 of the distal annular braided mesh 62.

[0048] In other embodiments, a developing mark is provided on the proximal edge and / or the distal edge of the annular woven mesh 62 at the proximal end of the coating 20; a developing mark may also be provided on the proximal edge and / or the distal edge of the annular woven mesh 62 at the distal end of the coating 20.

[0049] Please also read Figures 4 to 6The structure of the coated vascular stent provided in the third embodiment of the present invention is similar to that of the first embodiment, except that: in the third embodiment, the expansion positioning member 60 further includes an annular corrugated expansion rod 65, which includes a plurality of Z-shaped or sinusoidal support units connected end to end, each of which includes a crest 651, a trough 653, and a wave rod 655 connected between the crest 651 and the trough 653. The annular corrugated expansion rod 65 is made of superelastic nickel-titanium by laser cutting. The trough 653 of the annular corrugated expansion rod 65 is connected to the annular braided mesh 62. When the coated vascular stent is implanted in the corresponding blood vessel and deployed, the annular corrugated expansion rod 65 is deployed to drive the annular braided mesh 62, so that the annular braided mesh 62 and the annular corrugated expansion rod 65 are deployed together, and the radial support force of the two can tightly fit the coating 20 to the inner wall of the blood vessel, so that the coating 20 and the inner wall of the blood vessel are sealed and fitted to prevent internal leakage; because the main support frame 40, the annular braided mesh 62 and the annular corrugated expansion rod 65 have radial expansion force on the inner wall of the blood vessel after deployment, the coated vascular stent can be stably positioned on the inner wall of the blood vessel to prevent the coated vascular stent from displacement.

[0050] In this embodiment, the annular corrugated expansion rod 65 has 5 peaks and troughs, the wall thickness of the annular corrugated expansion rod 65 is 0.4mm, and the width of the wave rod is 0.45mm, so that the annular corrugated expansion rod 65 has a large radial support strength. The proximal edge of the annular braided mesh 62 is flush with the proximal edge of the coating 20, and the trough of the annular corrugated expansion rod 65 is connected to the proximal edge of the annular braided mesh 62. Since the annular braided mesh 62 itself has superelasticity and a certain rigidity, in addition, the radial support force of the annular corrugated expansion rod 65 acts evenly on the proximal end of the coating 20 through the annular braided mesh 62 as an intermediate, so that the proximal edge of the coating 20 is completely in contact with the blood vessel wall, which greatly improves the wall adhesion performance of the coated vascular stent 100 and prevents internal leakage.

[0051] like Figure 5 As shown, the annular corrugated expansion rod 65 is sutured and connected with the annular braided mesh 62 by medical sutures or medical glue. Specifically, the intersection of the trough 653 of the annular corrugated expansion rod 65 and the annular braided mesh 62 is spirally wound around the trough 653 as a path by medical sutures, and the sutures sew the coating 20 and the annular braided mesh 62 on the suture path together with the annular corrugated expansion rod 65; or the trough 653 of the annular corrugated expansion rod 65, the coating 20 and the annular braided mesh 62 are glued together by medical glue at the intersection of the trough 653 of the annular corrugated expansion rod 65 and the annular braided mesh 62.

[0052] like Figure 6As shown, the annular corrugated expansion rod 65 is provided with anchoring barbs 656, and these anchoring barbs 656 are arranged at least in one circle along the circumference of the annular corrugated expansion rod 65. After the coated vascular stent 100 is implanted, the anchoring barbs 656 can penetrate into the inner wall of the blood vessel to further anchor the coated vascular stent 100. The anchoring stability is better by using the anchoring barbs 656, and the coated vascular stent 100 can be prevented from falling off.

[0053] In this embodiment, the anchoring barb 656 is disposed on each crest 651 of the annular corrugated expansion rod 65 , and two opposite inner side surfaces of the crest 651 extend an anchoring barb 656 obliquely toward the annular braided mesh 62 .

[0054] In other embodiments, anchoring barbs 656 may be provided on the wave rods 655 and / or the wave valleys 653 of the annular wave-shaped expansion and support rods 65 .

[0055] In other embodiments, anchor barbs may be provided on the annular corrugated expansion rod 65 and the annular braided mesh 62 .

[0056] In other embodiments, the distal end of the coating 20 may also be provided with an annular braided mesh 62 and an annular corrugated expansion rod 65. Specifically, each crest of the annular corrugated expansion rod 65 is connected to the annular braided mesh 62, and the annular corrugated expansion rod 65, except for the crest, is exposed to the distal end surface of the coating 20. Anchor barbs 656 may also be provided on the distal end annular corrugated expansion rod 65. The distal end surface of the coating 20 extends to the crest of the distal end annular corrugated expansion rod 65.

[0057] In other embodiments, at least one circle of developing marks may be provided on the annular corrugated expansion rod 65 along the circumferential direction.

[0058] Please also read Figure 7 and Figure 8The structure of the coated vascular stent provided in the fourth embodiment of the present invention is similar to that of the third embodiment, except that: in the fourth embodiment, the crest 651 of the annular corrugated expansion rod 65 is connected to the annular braided mesh 62 at the proximal end of the coating 20, and preferably, the proximal surface 625 of the annular braided mesh 62 is flush with the crest 651 of the annular corrugated expansion rod 65. Specifically, the annular corrugated expansion rod 65 is lower than the proximal surface of the annular braided mesh 62, that is, the annular corrugated expansion rod 65 does not expose the proximal surface 625 of the annular braided mesh 62, so that each crest 651 of the annular corrugated expansion rod 65 is connected to the annular braided mesh 62, and the proximal surface of the coating 20 extends to the annular braided mesh 62, and preferably, the proximal surface of the coating 20 is flush with the proximal surface of the annular braided mesh 62. When the coated vascular stent 100 is in the expanded state, the radial supporting force of the crest 651 of the annular corrugated expansion rod 65 supports the annular braided mesh 62, and together with the annular braided mesh 62, the proximal end of the coating 20 is tightly fitted to the inner wall of the blood vessel, so that the coating 20 and the inner wall of the blood vessel are sealed to prevent internal leakage; and the trough 653 and the wave rod 655 of the annular corrugated expansion rod 65 can radially expand the coating 20, so that the fit between the coating 20 and the inner wall of the blood vessel is more sealed.

[0059] The annular corrugated expansion strut 65 in this embodiment is also provided with anchoring barbs 656 . Specifically, the anchoring barbs 656 are provided at each wave crest 651 of the annular corrugated expansion strut 65 .

[0060] See also Fig. 9 The structure of the coated vascular stent provided in the fifth embodiment of the present invention is similar to that of the third embodiment, except that: in the fifth embodiment, the distal end of the main support frame 40 is connected to a branch stent 42, and the outer diameter of the branch stent 42 is smaller than the outer diameter of the main support frame 40. Specifically, two branch stents 42 are arranged at the distal end of the main support frame 40, and the structure of each branch stent 42 is similar to that of the main support frame 40, that is, it includes a tubular coating and a plurality of Z-shaped or sinusoidal corrugated support rods arranged on the coating.

[0061] In other embodiments, an opening is formed on the outer peripheral wall of the coating 20 , and the opening is extended into the cavity of the main support frame 40 and is provided with an embedded branch.

[0062] See also Fig.10The structure of the coated vascular stent provided in the sixth embodiment of the present invention is similar to that of the first embodiment, except that: in the sixth embodiment, anchoring barbs 627 are arranged on the annular braided mesh 62. Specifically, a plurality of anchoring barbs 627 are circumferentially arranged on the proximal edge of the annular braided mesh 62. After the coated vascular stent is implanted, the anchoring barbs 627 can penetrate into the inner wall of the blood vessel to further anchor the coated vascular stent, thereby improving the anchoring stability and preventing the coated vascular stent from falling off.

[0063] In other embodiments, anchoring barbs 627 may be provided at the middle or distal end of the annular braided mesh 62 .

[0064] Please also read Fig.11 and Fig.12 The structure of the coated vascular stent provided in the seventh embodiment of the present invention is similar to that of the third embodiment, except that: in the seventh embodiment, the annular positioning frame is an annular positioning rod 64, and the annular positioning rod 64 is fixed to the outer surface or inner surface of the proximal end or distal end of the coating 20. In this embodiment, the annular positioning rod 64 is fixed to the proximal end of the coating 20, and the annular positioning rod 64 is made of nickel-titanium alloy wire greater than 0.1 mm.

[0065] The annular positioning rod 64 is an expandable support ring made of elastic memory alloy, preferably, the annular positioning rod 64 is a support ring of nickel-titanium alloy. The annular positioning rod 64 can be woven from a memory alloy wire, or can be integrally cut from the memory alloy by laser.

[0066] The annular positioning rod 64 can be connected to the coating 20 by suturing, hot pressing or gluing, so that the annular positioning rod 64 and the coating 20 can be tightly fixed, and the annular positioning rod 64 and the annular corrugated expansion rod 65 are also connected by suturing, hot pressing or gluing. After the coated vascular stent 100 is implanted in a blood vessel, the annular corrugated expansion rod 65 is unfolded to expand the annular positioning rod 64 and expand the coating 20 through radial support force, so that the coating 20 and the inner wall of the blood vessel 20 are sealed and fitted to avoid internal leakage.

[0067] In this embodiment, the annular positioning rod 64 and the annular corrugated expansion rod 65 are both located at the proximal end of the coating 20, and the trough 653 of the annular corrugated expansion rod 65 is connected to the annular positioning rod 64, that is, the trough 653 of the annular corrugated expansion rod 65 is lower than the proximal surface of the coating 20, and the annular corrugated expansion rod 65, except for the trough 653, the wave rod 655 and the wave crest 651 are all exposed to the proximal surface of the coating 20. The trough 653 of the annular corrugated expansion rod 65 is connected to the annular positioning rod 64 by a medical suture. The annular positioning rod 64 is provided with a connecting arc rod 642 corresponding to the trough 653 of the annular corrugated expansion rod 65, and the connecting arc rod 642 is bent and extended along the corresponding trough 653, and each trough 653 is connected to the corresponding connecting arc rod 642. Specifically, the annular positioning rod 64 is bent toward the distal end corresponding to each trough 653 of the annular corrugated expansion rod 65 to form an arc-shaped connecting arc rod 642, and the connecting arc rod 642 is bent along the bend of the corresponding trough 653. The medical suture between the trough 653 of the annular corrugated expansion rod 65 and the corresponding connecting arc rod 642 follows the waveform of each trough 653 and accompanies the entire trough 653, and the medical suture sutures the corresponding covering film 20.

[0068] The annular positioning rod 64 may also be provided with anchoring barbs along its circumference.

[0069] The annular positioning rod 64 is provided with a connecting arc rod 642 corresponding to the trough 653, which can increase the connection length between the annular positioning rod 64 and the annular corrugated expansion rod 65, making the connection between the annular positioning rod 64 and the annular corrugated expansion rod 65 more secure, and facilitating the annular corrugated expansion rod 65 to transmit the radial supporting force to the coating 20 through the annular positioning rod 64.

[0070] In other embodiments, the distal end of the coating 20 may also be provided with an annular positioning rod 64 and an annular corrugated expansion rod 65, the crest 651 of the annular corrugated expansion rod 65 is connected to the annular positioning rod 64, that is, the crest 651 of the annular corrugated expansion rod 65 is attached to the distal end of the coating 20, and the annular corrugated expansion rod 65, except for the crest 651, the wave rod 655 and the trough 653 are exposed to the distal end surface of the coating 20. The crest 651 of the annular corrugated expansion rod 65 is connected to the annular positioning rod 64 by a medical suture. The annular positioning rod 64 is provided with a connecting arc rod corresponding to the crest 651 of the annular corrugated expansion rod 65, and the connecting arc rod is bent and extended along the corresponding crest 651, and each crest 651 is connected to the corresponding connecting arc rod 642. Specifically, the annular positioning rod 64 is bent toward the proximal end corresponding to each crest 651 of the annular corrugated expansion rod 65 to form an arc-shaped connecting arc rod, and the connecting arc rod is bent along the bend of the corresponding crest 651. The medical suture between the crest 651 of the annular corrugated expansion rod 65 and the corresponding connecting arc rod follows the waveform of each crest 651 and accompanies the entire crest 651, and the medical suture sutures the corresponding covering film 20.

[0071] Please also read Fig.13 and Fig.14 The structure of the coated vascular stent provided in the eighth embodiment of the present invention is similar to that of the seventh embodiment, except that: in the eighth embodiment, the crest 651 of the annular corrugated expansion rod 65 is connected to the annular positioning rod 64 at the proximal end of the coating 20. Specifically, the annular positioning rod 64 and the annular corrugated expansion rod 65 are both arranged at the proximal end of the coating, the annular positioning rod 64 is closer to the proximal surface of the coating 20 than the annular corrugated expansion rod 65, the annular corrugated expansion rod 65 is lower than the proximal surface of the annular braided mesh 62, that is, the annular corrugated expansion rod 65 does not expose the proximal surface 625 of the annular braided mesh 62, and the annular corrugated expansion rod 65 is closer to the distal end than the annular positioning rod 64. The annular positioning rod 64 is connected to the crest 651 of the annular corrugated expansion rod 65. When the coated vascular stent 100 is unfolded, the radial supporting force of the crest 651 of the annular corrugated expansion rod 65 expands the annular positioning rod 64. The radial supporting force of the annular positioning rod 64 and the radial supporting force of the annular corrugated expansion rod 65 together expand the proximal end of the coating 20, so that the coating 20 is sealed with the inner wall of the blood vessel to prevent internal leakage; and the trough 653 and the rod 655 of the annular corrugated expansion rod 65 can radially expand the coating 20, so that the coating 20 is sealed and fits the inner wall of the blood vessel.

[0072] The annular positioning rod 64 is provided with a connecting arc rod 645 corresponding to the wave crest 651 of the annular corrugated expansion rod 65, and the connecting arc rod 645 is bent and extended along the corresponding wave crest 651, and each wave crest 651 is connected to the corresponding connecting arc rod 645. Specifically, the annular positioning rod 64 is bent toward the proximal end corresponding to each wave crest 651 of the annular corrugated expansion rod 65 to form an arc-shaped connecting arc rod 645, and the connecting arc rod 645 is bent along the bend of the corresponding wave crest 651. The medical suture between the wave crest 651 of the annular corrugated expansion rod 65 and the corresponding connecting arc rod 645 follows the waveform of each wave crest 651 and accompanies the entire wave crest 651, and the medical suture sutures the corresponding covering film 20.

[0073] Please also read Fig.15 and Fig.16 The structure of the coated vascular stent provided in the ninth embodiment of the present invention is similar to that of the third embodiment, except that: in the ninth embodiment, the annular positioning frame is at least one annular connecting rope 68, and the annular connecting rope 68 is fixed to the outer surface or inner surface of the coating 20. Specifically, the annular connecting rope 68 is fixed to the outer surface or inner surface of the proximal end or distal end of the coating 20. In this embodiment, the annular connecting rope 68 is fixed to the proximal end of the coating 20, specifically, the annular connecting rope 68 is connected between the trough 653 of the annular corrugated expansion rod 65 and the crest 421 of the most proximal corrugated support rod 42.

[0074] The annular connecting rope 68 is an expandable support ring made of elastic memory alloy, preferably, the annular connecting rope 68 is a support ring of nickel-titanium alloy. The annular connecting rope 68 is woven from a memory alloy wire.

[0075] The annular connecting rope 68 can be connected to the film 20 by suturing, hot pressing or gluing, so that the annular connecting rope 68 and the film 20 can be tightly fixed, and the connection between the annular connecting rope 68 and the annular corrugated expansion rod 65 is completed by the annular connecting rope 68 being wound around the trough 653 of the annular corrugated expansion rod 65. After the coated vascular stent 100 is implanted in the blood vessel, the annular positioning rod 64 and the annular corrugated expansion rod 65 radially expand the annular connecting rope 68 to drive the most proximal corrugated support rod 42 to radially expand the film 20 together, so that the film 20 and the inner wall of the blood vessel are sealed and fitted to prevent internal leakage; and after the main support frame 40, the annular connecting rope 68 and the annular corrugated expansion rod 65 are deployed, they all have radial expansion force on the inner wall of the blood vessel, which can stably position the coated vascular stent on the inner wall of the blood vessel to prevent the displacement of the coated vascular stent.

[0076] The annular connecting rope 68 is wound around each trough 653 of the annular corrugated expansion and support rod 65 at least once. In this embodiment, the annular connecting rope 68 is wound around each trough 653 of the annular corrugated expansion and support rod 65 twice.

[0077] In other embodiments, the distal end of the coating 20 may also be provided with an annular connecting rope 68 and an annular corrugated expansion rod 65, the annular connecting rope 68 is wound between the crest 651 of the annular corrugated expansion rod 65 and the trough of the most distal corrugated support rod 42, that is, the crest 651 of the annular corrugated expansion rod 65 is attached to the distal end of the coating 20, and the annular corrugated expansion rod 65, except for the crest 651, the rod 655 and the trough 653 are exposed to the distal end surface of the coating 20. The annular connecting rope 68 is wound between the crest 651 of the annular corrugated expansion rod 65 and the trough of the most distal corrugated support rod 42.

[0078] In other embodiments, the entanglement between the annular connecting rope 68 and the trough 653 / peak 651 of the annular corrugated expansion rod 65, and the entanglement between the annular connecting rope 68 and the peak / trough of the corrugated support rod 42 can be knotted and fixed.

[0079] In other embodiments, the annular connecting rope 68 can be replaced by a developing wire containing developing material, and the developing wire is preferably a nickel-titanium alloy wire containing tantalum.

[0080] The above is an implementation of the embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the embodiment of the present invention. These improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A coated vascular stent with improved wall adhesion performance, comprising a coating and a main support frame arranged on the coating, characterized in that: The coated vascular stent further comprises an expansion and support positioning member arranged at the proximal end and / or the distal end of the coating, and after the coated vascular stent is subjected to radial compression, the radial support force of the expansion and support positioning member can maintain the complete expansion of the proximal end and / or the distal end of the coating; The expansion and support positioning member includes an annular positioning frame, the annular positioning frame can be radially expanded, the coating is fixed on the annular positioning frame, and the expansion and support positioning member also includes an annular corrugated expansion and support rod with wave crests and wave troughs; The annular positioning frame is an annular positioning rod, and a connecting arc rod is provided on the annular positioning rod, which is correspondingly connected to the crest or trough of the annular corrugated expansion rod. The connecting arc rod is bent and extended along the corresponding crest or trough, and the connecting arc rod is connected to the crest or trough; the annular positioning rod is connected to the membrane, and the annular corrugated expansion rod unfolds the annular positioning rod and expands the membrane through radial support force, so that the membrane is sealed and fits with the inner wall of the blood vessel.

2. The coated vascular stent according to claim 1, characterized in that: The annular positioning rod is woven from elastic memory alloy wires.

3. The coated vascular stent according to claim 1, characterized in that: The annular positioning rod is fixed on the covering film by means of suturing, heat pressing or gluing.

4. The coated vascular stent according to claim 1, characterized in that: The trough or crest of the annular corrugated expansion rod is connected to the annular positioning frame by medical suture or medical glue. After the annular corrugated expansion rod and the annular positioning frame are unfolded, they radially expand the coating so that the coating maintains a complete circular ring structure at its end.

5. The coated vascular stent according to claim 4, characterized in that: The annular corrugated expansion support rod and / or the annular positioning frame are provided with anchoring barbs.

6. The coated vascular stent according to claim 5, characterized in that: The annular positioning frame and the annular corrugated expansion rod are both located at the proximal end of the coating, and the proximal end of the annular positioning frame is connected to the trough or crest of the annular corrugated expansion rod; or the annular positioning frame and the annular corrugated expansion rod are both located at the distal end of the coating, and the distal end of the annular positioning frame is connected to the crest or trough of the annular corrugated expansion rod.

7. The coated vascular stent according to claim 6, characterized in that: The wave crest of the annular corrugated expansion rod is flush with the proximal end surface of the proximal annular positioning frame; the wave trough of the annular corrugated expansion rod is flush with the distal end surface of the distal annular positioning frame.

8. The coated vascular stent according to claim 1, characterized in that: The annular positioning frame is provided with a developing mark.

9. A coated vascular stent with improved wall adhesion performance, comprising a coating and a main support frame arranged on the coating, characterized in that: The coated vascular stent further comprises an expansion and support positioning member arranged at the proximal end and / or the distal end of the coating, and after the coated vascular stent is subjected to radial compression, the radial support force of the expansion and support positioning member can maintain the complete expansion of the proximal end and / or the distal end of the coating; The expansion and support positioning member includes an annular positioning frame, the annular positioning frame can be radially expanded, the coating is fixed on the annular positioning frame, and the expansion and support positioning member also includes an annular corrugated expansion and support rod with wave crests and wave troughs; The annular positioning frame is at least one annular connecting rope, which is wrapped around each crest or each trough of the annular corrugated expansion rod at least once, and the annular connecting rope is connected to the main support frame; the annular corrugated expansion rod radially expands the annular connecting rope to drive the main support frame connected to the annular connecting rope to radially expand the membrane, so that the membrane is sealed and fits the inner wall of the blood vessel.

10. The coated vascular stent according to claim 9, characterized in that: The at least one annular connecting rope is braided from elastic memory alloy wires.

11. The coated vascular stent according to claim 9, characterized in that: The at least one annular connecting rope is fixed to the covering film by means of sewing, hot pressing or gluing.

12. The coated vascular stent according to claim 9, characterized in that: The trough or crest of the annular corrugated expansion rod is connected to the annular positioning frame by medical suture or medical glue. After the annular corrugated expansion rod and the annular positioning frame are unfolded, they radially expand the coating so that the coating maintains a complete circular ring structure at its end.

13. The coated vascular stent according to claim 12, characterized in that: The annular corrugated expansion support rod and / or the annular positioning frame are provided with anchoring barbs.

14. The coated vascular stent according to claim 13, characterized in that: The annular positioning frame and the annular corrugated expansion rod are both located at the proximal end of the coating, and the proximal end of the annular positioning frame is connected to the trough or crest of the annular corrugated expansion rod; or the annular positioning frame and the annular corrugated expansion rod are both located at the distal end of the coating, and the distal end of the annular positioning frame is connected to the crest or trough of the annular corrugated expansion rod.

15. The coated vascular stent according to claim 14, characterized in that: The wave crest of the annular corrugated expansion rod is flush with the proximal end surface of the proximal annular positioning frame; the wave trough of the annular corrugated expansion rod is flush with the distal end surface of the distal annular positioning frame.

16. The coated vascular stent according to claim 9, characterized in that: The annular positioning frame is provided with a developing mark.

17. A coated vascular stent with improved wall adhesion performance, comprising a coating and a main support frame arranged on the coating, characterized in that: The coated vascular stent further comprises an expansion and support positioning member arranged at the proximal end and / or the distal end of the coating, and after the coated vascular stent is subjected to radial compression, the radial support force of the expansion and support positioning member can maintain the complete expansion of the proximal end and / or the distal end of the coating; The expansion and support positioning member includes an annular positioning frame, the annular positioning frame can be radially expanded, the coating is fixed on the annular positioning frame, and the expansion and support positioning member also includes an annular corrugated expansion and support rod with wave crests and wave troughs; The annular positioning frame is an annular braided mesh, which is connected to each crest or each trough of the annular corrugated expansion rod, and the annular braided mesh is connected to the membrane. The expansion of the annular corrugated expansion rod drives the annular braided mesh to expand together, and expands the membrane through radial support force, so that the membrane is sealed and fitted with the inner wall of the blood vessel; Also includes any one of the following technical solutions: A. The annular positioning frame and the annular corrugated expansion rod are both located at the proximal end of the coating, the proximal end of the annular positioning frame is connected to the trough of the annular corrugated expansion rod, the trough of the annular corrugated expansion rod is connected to the proximal edge of the annular braided net, and a portion of the trough of the annular corrugated expansion rod overlaps with the annular braided net; or B. The annular positioning frame and the annular corrugated expansion rod are both located at the proximal end of the coating, the proximal end of the annular positioning frame is connected to the crest of the annular corrugated expansion rod, and the crest of the annular corrugated expansion rod is flush with the proximal end surface of the proximal annular positioning frame; or C. The annular positioning frame and the annular corrugated expansion rod are both located at the distal end of the coating, the distal end of the annular positioning frame is connected to the crest of the annular corrugated expansion rod, the crest of the annular corrugated expansion rod is connected to the distal edge of the annular braided net, and a portion of the crest of the annular corrugated expansion rod overlaps with the annular braided net; or D. The annular positioning frame and the annular corrugated expansion rod are both located at the distal end of the coating, the distal end of the annular positioning frame is connected to the trough of the annular corrugated expansion rod, and the trough of the annular corrugated expansion rod is flush with the distal end surface of the annular positioning frame at the distal end.

18. The coated vascular stent according to claim 17, characterized in that: The annular braided mesh is braided from elastic memory alloy wires.

19. The coated vascular stent according to claim 17, characterized in that: The annular braided mesh is fixed on the covering film by means of suturing, heat pressing or gluing.

20. The coated vascular stent according to claim 17, characterized in that: The annular braided mesh is braided by warp threads and weft threads that are interlaced with each other.

21. The coated vascular stent according to claim 17, characterized in that: The weaving mesh holes of the annular weaving mesh are rhombus or rectangular.

22. The coated vascular stent according to claim 17, characterized in that: The weaving mesh holes of the annular weaving mesh are polygonal.

23. The coated vascular stent according to any one of claims 17 to 22, characterized in that: The proximal surface of the coating is located between the proximal surface and the distal surface of the proximal annular braided mesh; the distal surface of the coating is located between the proximal surface and the distal surface of the proximal annular braided mesh.

24. The coated vascular stent according to claim 23, characterized in that: The trough or crest of the annular corrugated expansion rod is connected to the annular positioning frame by medical suture or medical glue. After the annular corrugated expansion rod and the annular positioning frame are unfolded, they radially expand the coating so that the coating maintains a complete circular ring structure at its end.

25. The coated vascular stent according to claim 24, characterized in that: The annular corrugated expansion support rod and / or the annular positioning frame are provided with anchoring barbs.

26. The coated vascular stent according to claim 17, characterized in that: The annular braided net is provided with a developing mark.

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