阅读说明：本技术 用于血管的支架 (Stent for blood vessels ) 是由 王雪琴 李�杰 朱京 刘伟 于 2021-08-03 设计创作，主要内容包括：本发明涉及一种用于血管的支架。该支架包括：相连接的包覆膜与锚定件；锚定件用于将包覆膜固定在血管内；包覆膜用于兜拢血管的病变部位。该支架的锚定件用于在支架受到血液的冲刷时将包覆膜更好地贴附血管内膜,固定在预期植入位置,包覆膜可以兜拢血管内膜上的不稳定斑块,避免不稳定斑块破裂,同时包覆膜也可以在生物体内引发异物反应,从而刺激血管内皮生长,使不稳定斑块生长为稳定斑块,减小急性血栓发生率。且该支架也可以用于介入过程中血管撕裂的处理,避免撕裂血管壁脱落造成血栓事件。(The present invention relates to a stent for a blood vessel. This support includes: the connected coating film and the anchor; the anchoring piece is used for fixing the covering film in the blood vessel; the coating film is used for closing up the lesion part of the blood vessel. The anchoring part of the stent is used for better attaching the coating film to the intima of a blood vessel when the stent is washed by blood, the coating film is fixed at an expected implantation position, unstable plaque on the intima of the blood vessel can be tucked by the coating film, the rupture of the unstable plaque is avoided, foreign body reaction can be caused in a living body by the coating film, and therefore the growth of the endothelium of the blood vessel is stimulated, the unstable plaque is grown into the stable plaque, and the incidence rate of acute thrombosis is reduced. And the stent can also be used for treating blood vessel tearing in the interventional process, so that the thrombus event caused by the falling of the torn blood vessel wall is avoided.)

1. A stent for a blood vessel, comprising a cover (100) and an anchor (200) connected;

the anchoring elements (200) are arranged at two ends of the bracket along the axial direction of the bracket and are used for fixing the bracket in the blood vessel;

the cover film (100) is fixed by the anchor member (200) for closing the lesion site of the blood vessel, wherein the outer surface of the cover film (100) contains a cell adhesion substance.

2. The stent of claim 1 wherein the cover film (100) is a bioabsorbable material, wherein the bioabsorbable material includes at least one of polyesters, polycarbonates, and composites thereof.

3. The stent according to claim 1 wherein the porosity of the cover film (100) is between 50% and 100%.

4. The stent according to any one of claims 1 to 3, wherein the porosity of the coating film (100) is greater at both end portions than at a central portion, which are sequentially distributed in the axial direction of the stent.

5. A support according to any one of claims 1 to 3, characterized in that the thickness of the cover film (100) is less than or equal to 100 μm.

6. A stent according to any one of claims 1 to 3, wherein the number of the anchoring elements (200) on the same end of the stent is plural and the anchoring elements (200) are distributed in sequence in the axial direction of the stent.

7. A stent according to claim 6 wherein two adjacent anchors (200) on the same end of the stent are spaced apart and connected by a connector (300).

8. A bracket according to any one of claims 1-3, characterized in that at least one supporting element (400) is connected between two adjacent anchoring elements (200) at different ends of the bracket, said supporting element (400) being located inside the cover film (100).

9. The bracket according to claim 8, characterized in that the support (400) is also fixed to the middle of the covering film (100).

10. A stent according to claim 8, wherein the length of the supporting element (400) in the axial direction of the stent is greater than the distance between two adjacent anchors (200) at different ends of the stent to arch the cover film (100).

11. The stent of claim 10, wherein the length of the supporting member (400) in the axial direction of the stent is 5% to 20% longer than the distance between two adjacent anchoring members (200) at different ends of the stent.

12. A support according to any one of claims 1 to 3, characterized in that the anchors (200) at the ends of the support are spaced from the covering film (100) and are connected to the covering film (100) by means of mounting elements (500).

13. A stent according to any one of claims 1 to 3 wherein the anchoring elements (200) are formed by joining in-line, undulating or bent anchoring strips end to end.

14. A stent according to any one of claims 1 to 3, wherein the width of the anchor (200) is between 50 μm and 5000 μm.

15. A stent according to any one of claims 1 to 3, wherein the area of the anchoring element (200) adjacent to the inner wall of the blood vessel is provided with a recess.

Technical Field

The invention relates to the technical field of medical instruments, in particular to a stent for blood vessels.

Background

Atherosclerosis is now considered to be a chronic inflammatory disease, the main lesion of which is characterized by the deposition of subintimal lipids in certain parts of the artery, with the concomitant proliferation of smooth muscle cells and fibrous matrix components, progressing to the formation of atherosclerotic plaques, causing stenosis or thrombosis of the vascular lumen. Wherein, the plaque is gradually enlarged along with the chronic progress of the lesion and is classified as stable or unstable plaque. Unstable plaques are characterized by a large lipid core covered by a thin and unstable fibrous cap, prone to rupture, which can lead to thrombosis and thus acute arterial symptoms, with a high risk. In contrast, the fibrous cap of the stable plaque is thick and not easily ruptured, and clinically appears as symptoms caused by ischemia induced by physical activity.

It has been found that the risk of atherothrombotic and thromboembolic complications appears to be more related to the stability of atherosclerotic plaques than to the size of the plaque. Stable angina is associated with smooth fibrous coronary plaque (stable plaque), while unstable angina, Acute Myocardial Infarction (AMI) and sudden cardiac death are all almost related to plaque instability.

Disclosure of Invention

In view of the above, it is necessary to provide a stent for a blood vessel in order to solve the technical problem that an existing atherosclerotic plaque is easily ruptured.

A stent for a blood vessel, the stent comprising: the connected coating film and the anchor;

the anchoring elements are arranged at two ends of the bracket along the axial direction of the bracket and are used for fixing the bracket in a blood vessel;

the cover film is fixed by the anchoring piece and is used for closing the lesion part of the blood vessel, wherein the outer surface of the cover film contains cell adhesion substances.

In one embodiment, the covering film is made of a bioabsorbable material, wherein the bioabsorbable material includes at least one of polyester, polycarbonate and a composite thereof.

In one embodiment, the coating film has a porosity of 50% to 100%.

In one embodiment, the porosity of the two end parts of the coating film distributed along the axial direction of the bracket in sequence is larger than that of the middle part.

In one embodiment, the thickness of the cover film is less than or equal to 100 μm.

In one embodiment, the number of the anchors on the same end of the stent is plural and the anchors are distributed in sequence along the axial direction of the stent.

In one embodiment, two adjacent anchors on the same end of the stent are spaced apart and connected by a connector.

In one embodiment, at least one supporting piece is connected between two adjacent anchoring pieces at different ends of the bracket, and the supporting piece is positioned on the inner side of the covering film.

In one embodiment, the support is further fixed to a middle portion of the cover film.

In one embodiment, the length of the supporting element in the axial direction of the bracket is larger than the distance between two adjacent anchoring elements at different ends of the bracket so as to arch the covering film.

In one embodiment, the length of the supporting member in the axial direction of the stent is 5% to 20% longer than the distance between two adjacent anchoring members at different ends of the stent.

In one embodiment, the anchors at the ends of the legs are spaced from the cladding film and are connected to the cladding film by mounting members.

In one embodiment, the anchor is formed by connecting straight, wavy or bent anchor strips head and tail.

In one embodiment, the width of the anchor is 50 μm to 5000 μm.

In one embodiment, the region of the anchor element proximate the inner wall of the blood vessel is provided with a recess.

The anchoring piece is used for better attaching the coating film to the intima of the blood vessel when the stent is washed by blood and fixing the coating film at the expected implantation position, the coating film is used for containing unstable plaques on the intima of the blood vessel and avoiding the rupture of the unstable plaques, and the outer surface of the coating film contains cell adhesion substances, the cell adhesive substance can form adhesive force with cells on the vessel wall by using the principle of similar intermiscibility, can prevent the coating film from excessively collapsing due to insufficient holding force, thereby ensuring that the coating film can effectively play a role of closing up the lesion part (especially the lesion part with overlarge volume or overlarge weight), effectively avoiding the rupture of unstable plaque, simultaneously the coating film can also cause foreign body reaction in the organism, thereby stimulating the growth of vascular endothelium, leading the unstable plaque to grow into stable plaque and reducing the incidence rate of acute thrombosis. And the stent can also be used for treating blood vessel tearing in the interventional process, so that the thrombus event caused by the falling of the torn blood vessel wall is avoided.

Drawings

Fig. 1 is a schematic structural view of a stent for a blood vessel according to an embodiment of the present invention;

FIG. 2 is a schematic structural view of a stent for a blood vessel according to another embodiment of the present invention;

FIG. 3 is a schematic structural view of a stent for a blood vessel according to another embodiment of the present invention;

FIG. 4 is a schematic structural diagram of a stent for a blood vessel according to another embodiment of the present invention;

fig. 5 is a schematic structural view of a stent for a blood vessel according to another embodiment of the present invention.

Wherein the reference numerals in the drawings are as follows:

100. coating a film; 200. an anchor; 300. a connecting member; 400. a support member; 500. and (4) a mounting piece.

Detailed Description

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the invention and to simplify the description, and are not intended to indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and are not to be considered limiting of the invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In the present invention, unless otherwise expressly stated or limited, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through an intermediate. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.

It will be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and the like as used herein are for illustrative purposes only and do not denote a unique embodiment.

Referring to fig. 1, fig. 1 is a schematic structural view illustrating a stent for a blood vessel according to an embodiment of the present invention, which includes a cover film 100 and an anchor member 200 connected to each other; the anchors 200 are provided at both ends of the stent in the axial direction of the stent for fixing the stent in the blood vessel; the cover film 100 is fixed by the anchor member 200 for closing a lesion part of a blood vessel, wherein the outer surface of the cover film 100 contains a cell-adhesive substance

In the present embodiment, the lesion of the blood vessel may be an unstable plaque on the intima of the blood vessel, or a lesion causing thrombus such as a torn region of the intima of the blood vessel. It should be noted that "tucking" herein means to be tucked and tucked, that is, a supporting force can be provided to a diseased part (for example, an unstable plaque) on an intima of a blood vessel, so as to prevent the unstable plaque from excessively collapsing, and thus, the rupture of the unstable plaque can be effectively avoided.

In this embodiment, the cell adhesion substance contained in the outer surface of the covering film 100 is similar to the components of the cell surface layer on the blood vessel wall, so that the adhesion force between the cell adhesion substance and the cells on the blood vessel wall can be formed by using the similar intermiscibility principle, and thus when the diseased region of the blood vessel is too large or too heavy, the excessive collapse of the covering film 100 due to insufficient closing force can be prevented by using the adhesion force, thereby ensuring that the covering film 100 can effectively play a role in closing the diseased region. During preparation, the surface of the coating film 100 can be directly coated with cell adhesion substances and then dried or aired. Wherein the cell adhesion substance may include at least one of a protein, a physiologically active substance, and a compound.

Examples of the above-mentioned protein include carcinoembryonic antigen, squamous cell carcinoma-associated antigen, cytokeratin 19 fragment, sialylated oligosaccharide antigen KL-6, disease markers such as natriuretic peptide, troponin, and myoglobin, interleukin-1 (IL-1), interleukin-2 (IL-2), interleukin-3 (IL-3), interleukin-4 (IL-4), interleukin-5 (IL-5), interleukin-6 (IL-6), interleukin-7 (IL-7), interleukin-8 (IL-8), interleukin-9 (IL-9), interleukin-10 (IL-10), interleukin-11 (IL-11), and, Interleukin-12 (IL-12), interleukin-13 (IL-13), interleukin-14 (IL-14), interleukin-15 (IL-15), interleukin-18 (IL-18), interleukin-21 (IL-21), interferon-alpha (IFN-alpha), interferon-beta (IFN-beta), interferon-gamma (IFN-gamma), granulocyte colony-stimulating factor (G-CSF), monocyte colony-stimulating factor (M-CSF), granulocyte-macrophage colony-stimulating factor (GM-CSF), Stem Cell Factor (SCF), flk2/flt3 ligand (FL), leukemia cell inhibitory factor (LIF), tumor suppressor M (OM), Erythropoietin (EPO), Thrombopoietin (TPO), transforming growth factor-alpha (TGF-alpha), transforming growth factor-beta (TGF-beta), macrophage inflammatory protein-1 alpha (MIP-1 alpha), Epidermal Growth Factor (EGF), fibroblast growth factor 1, 2, 3,4, 5, 6, 7, 8, or 9(FGF-1, 2, 3,4, 5, 6, 7, 8, 9), nerve cell growth factor (NGF), Hepatocyte Growth Factor (HGF), Leukemia Inhibitory Factor (LIF), protease nexin (protease nexin) I, protease nexin II, platelet-derived growth factor (PDGF), Cholinergic Differentiation Factor (CDF), chemotactic factor, Notch ligand (Delta1, etc.), Wnt protein, angiopoietin-like protein 2, 3, 5, or 7(Angpt2, EGF-Delta 1, etc.), Wnt protein, angiopoietin-like protein 2, 3, 5, or 7, 3. 5, 7), insulin-like growth factor (IGF), insulin-like growth factor binding protein (IGFBP), Pleiotrophin (Pleiotrophin), insulin, growth hormone, and like cell growth factors, as well as collagen I to XIX, fibronectin, vitronectin, laminin-1 to 12, laminin 511, laminin 521, nitogen (japanese: ニトジェン), tenascin, thrombospondin, von Willebrand factor, osteopontin, fibrinogen, elastin, proteoglycan, cadherin, desmocollin, integrin, E-selectin, P-selectin, L-selectin, cell adhesion factors such as immunoglobulin superfamily, Matrigel, poly-D-lysine and poly-L-lysine, and antibodies such as IgG, IgM, IgA, IgD and IgE.

Examples of the physiologically active substance include D-glucosamine, D-galactosamine, neuraminic acid, hyaluronic acid, chondroitin sulfate, heparan sulfate (heparin sulfate), saccharides such as heparin, serotonin, norepinephrine, epinephrine, 3- (3, 4-dichlorophenyl) -1, 1-Dimethylurea (DCMU), atrazine, linuron and simazine.

Examples of the above-mentioned compounds include angiotensin I to IV, bradykinin, fibrinopeptide, natriuretic peptide, urodilatin, guanosine peptide, endothelin 1 to 3, salusin, urotensin, oxytocin, metaproten, antidiuretic hormone, adrenocorticotropic hormone, melanocyte stimulating hormone, endorphin, lipotropin, urocortin 1 to 3, luteinizing hormone releasing hormone, growth hormone releasing hormone, somatostatin, cortisol stabilizing protein (cortitin), prolactin releasing peptide, metastin (metastin), tachykinin, substance P, neurokinin, endonexin, neurotensin, neuromedicin, exendin (Japanese: ゼニン), ghrelin (ghrelin), obesity inhibin (obesity inhibin), melanin concentrating hormone, orexin, neuropeptide, neuroleptin, neoendorphin, neorphin, and neomycin, Endomorphins, nociceptin (nociceptin), pyroglutamate-acylated RF amide peptides, galanin, gastrins, cholecystokinins, secretin (secretin), relaxin, glucagon, adrenomedullin, amyrin, calcitonin, parathyroid hormone, defensins, thymosin, YIGSR peptides and like peptides; amino acids such as alanine, arginine, asparagine, aspartic acid, cysteine, glutamine, glutamic acid, glycine, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, proline, serine, threonine, tryptophan, tyrosine, valine, cystine, hydroxyproline, hydroxylysine, dihydroxyphenylalanine, thyroxine, phosphoserine, desmosine, β -alanine, sarcosine, ornithine, creatine, γ -aminobutyric acid, theanine (theanine), kainic acid, domoic acid, amanithine, and the like; 2-dimethylaminoethylamine (CAS number: 108-00-9 compound), N- (2-hydroxyethyl) ethylenediamine (CAS number: 111-41-1 compound), N- (2-aminoethyl) piperazine (CAS number: 140-31-8 compound), 4- (2-aminoethyl) morpholine (CAS number: 2038-03-1 compound), 1- (2-aminoethyl) -2-imidazolidinone (CAS number: 6281-42-1 compound), primary amines such as tryptamine (CAS No. 61-54-1 compound), histamine dihydrochloride (CAS No. 56-92-8 compound), tyramine (CAS No. 51-67-2 compound), and dopamine (CAS No. 51-61-6 compound); ethylenediamine dihydrochloride (CAS number: 333-18-6 compound), 1, 6-diaminohexane (CAS number: 124-09-4 compound), primary diamines of N, N' -bis (aminopropyl) piperazine (CAS number: 7209-38-3 compound), and the like.

As described above, the stent for a blood vessel, the anchoring member 200 serves to better adhere the cover film 100 to the inner wall of the blood vessel when the stent is washed by blood, to fix it at a desired implantation position, the cover film 100 serves to gather unstable plaque on the intima of the blood vessel, and the outer surface of the cover film 100 contains a cell-adhesive substance, the cell adhesive substance can form adhesive force with cells on the vessel wall by using the principle of similar intermiscibility, can prevent the coating film 100 from excessively collapsing due to insufficient holding force, thereby ensuring that the coating film 100 can effectively play a role of closing up the lesion part (especially the lesion part with overlarge volume or overlarge weight), effectively avoiding the rupture of unstable plaque, simultaneously the coating film 100 can also initiate foreign body reaction in the organism, thereby stimulating the growth of vascular endothelium, leading the unstable plaque to grow into stable plaque and reducing the incidence rate of acute thrombosis. And the stent can also be used for treating blood vessel tearing in the interventional process, so that the thrombus event caused by the falling of the torn blood vessel wall is avoided.

In patients with atherosclerotic carotid disease, plaque irregularities and rupture are closely associated with cerebral ischemic events, and patients with irregular or ulcerative plaques exhibit a higher risk of ischemic stroke, regardless of the degree of luminal stenosis. To address this problem, in some embodiments of the present invention, the wrapping film 100 is made of a flexible material. The coating film 100 made of the material can hold unstable plaques with different shapes, particularly unstable plaques with irregular shapes, and reduce the risk of ischemic stroke of patients with irregular plaques. Optionally, cover film 100 is a bioabsorbable material, wherein the bioabsorbable material includes at least one of polyesters (e.g., polycaprolactone, polylactic acid, polyglycolide), polycarbonate, and composites thereof. The cover film 100 of a bioabsorbable material may be degraded and absorbed in the human body.

In some embodiments of the invention, the porosity of the cover film 100 is 50% to 100%, for example, set at 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90, 95%, 100%, etc. Therefore, the wrapping film 100 can be ensured to be capable of closing the lesion part, and the flexibility of the wrapping film 100 can be ensured.

Specifically, the porosity of the two end portions of the cover film 100, which are sequentially distributed along the axial direction of the stent, is greater than the porosity of the middle portion. The central portion of the cover film 100 refers to a portion of the cover film 100 located between both end portions extending in the axial direction of the stent. It is understood that the cover film 100 includes two end portions (i.e., a first end portion, a second end portion) and a middle portion, and the first end portion, the middle portion and the second end portion are sequentially distributed along the axial direction of the stent, i.e., sequentially distributed along the blood flow direction. The middle part of the wrapping film 100 is used for closing the lesion part of the blood vessel and needs higher density; the two ends of cover film 100 are typically used to mount anchor 200, and the lower density provides for material savings and reduced processing difficulties. When in use, the porosity of the two ends and the middle part of the wrapping film 100 can be set according to specific conditions.

In some embodiments of the present invention, the thickness of the cover film 100 is less than or equal to 100 μm, and may be set to 100 μm, 90 μm, 80 μm, 70 μm, 60 μm, or the like, for example. Therefore, cells can be conveniently and better extended to the middle part of the coating film 100, the endothelialization of the blood vessel is accelerated, the coating film 100 is also softer, and less blood vessel lumens can be occupied. Preferably, the thickness of the cover film 100 is 50 μm or less, and for example, 50 μm, 40 μm, 30 μm, 20 μm, 10 μm, or the like may be provided.

In some embodiments of the present invention, cover film 100 may be formed by weaving, electrospinning, die pressing, or through cutting. When in use, the coating film 100 may be prepared by selecting a corresponding processing method according to the material of the coating film 100.

In some embodiments of the present invention, as shown in fig. 1, the number of the anchors 200 located on the same end portion of the stent is plural and the anchors 200 are sequentially distributed in the axial direction of the stent. It is understood that the stent includes two ends (i.e. a first end and a second end), the first end and the second end are distributed in sequence along the axial direction of the stent, i.e. in sequence along the blood flow direction, and the "same end" of the stent refers to the first end or the second end of the stent. The provision of a plurality of anchors 200 at the same end of the stent can improve the implantation firmness of the cover film 100 in the blood vessel. The number of anchors 200 at the same end of the stent may be specifically set as desired for use. For example, 2 anchors 200 are provided at one end of the cover film 100 shown in fig. 2, 3 anchors 200 are provided at the other end, and 3 anchors 200 are provided at both ends of the cover film 100 shown in fig. 3. Of course, in other embodiments of the present invention, the anchoring strength of the anchoring elements 200 can also be increased by increasing the length of the anchoring elements 200 in the axial direction of the stent, and it can be considered that, as shown in fig. 4, two adjacent anchoring elements 200 on the same end of the cover film 100 are attached and connected to each other, and two adjacent anchoring elements 200 can be connected by fusion welding or integrally molding (e.g., laser engraving).

Further, in some embodiments of the invention, as shown in fig. 2, two adjacent anchors 200 on the same end of the cover film 100 are spaced apart and connected by a connecting member 300. It is understood that the "same end" of the cover film 100 refers to either the first end or the second end of the cover film 100. Thus, the anchoring element 200 can be made into a hollow structure, the process of endothelialization of the blood vessel is accelerated, and the blood vessel delivery system can hold the anchoring element 200 more effortlessly, thereby facilitating the delivery of the stent. Alternatively, the connecting member 300 may be made of the same material as the anchor 200, the connecting member 300 may have a straight shape, a bent shape, a wavy shape, etc., and the connecting member 300 may be connected to the anchor 200 by fusion welding or integral molding (e.g., laser engraving).

In other embodiments of the invention, the area of the anchor 200 proximate the inner wall of the blood vessel may also be provided with a groove. The groove may facilitate the ingrowth of cells, allowing the anchoring element 200 to be more securely anchored within the vessel, thereby improving the security of the implantation of the cover 100 within the vessel. The shape of the groove is not limited in the embodiments of the present invention, and may be circular, polygonal, or the like. It should be noted that, when the anchoring element 200 is in a ring shape, the wall of the anchoring element 200 facing the inner wall of the blood vessel is the region of the anchoring element 200 adjacent to the inner wall of the blood vessel, and the wall of the anchoring element 200 facing away from the inner wall of the blood vessel is the wall of the anchoring element 200 near the central axis of the stent; when the anchoring element 200 includes a plurality of protrusions (e.g., wedge-shaped protrusions) arranged around the central axis of the stent and the protrusions are inserted into the inner wall of the blood vessel to perform the anchoring function, the wall of the protrusions inserted into the inner wall of the blood vessel is the wall of the anchoring element 200 away from the central axis of the stent, and the wall of the protrusions not inserted into the inner wall of the blood vessel is the region of the anchoring element 200 adjacent to the inner wall of the blood vessel. Wherein, the extension direction of the central axis of the bracket is parallel to the direction of blood flow.

In some embodiments of the invention, the anchor 200 is a loop structure. The fully enclosed anchor 200 ensures that the cover film 100 is in good contact with the inner wall of the vessel.

Specifically, the anchor 200 is formed by joining straight (see fig. 1, 3 to 5), wavy (see fig. 2), or bent anchor strips end to end. Wherein, when the anchoring member 200 is formed by connecting the straight anchoring strips head to tail, the difficulty of processing the stent for the blood vessel can be reduced. When the anchor 200 is formed by joining undulating or serpentine anchoring strips end to end, overall compression of the stent is facilitated, thereby facilitating implantation of the stent. When in use, the anchor 200 can be configured in different shapes to pocket different sized lesion sites.

In some embodiments of the invention, the anchor 200 has a width of 50 μm to 5000mm, and may be set to 50 μm, 100 μm, 1000 μm, 3000 μm, 5000 μm, or the like, for example. The width of the anchor 200 is greater than the width of each metal wave bar on a conventional stent graft, and the anchor 200 at this size is effective to anchor the cover 100 within the vessel. It should be noted that, as more anchors 200 are provided on the cover film 100, the width of the anchors 200 can be reduced accordingly.

In some embodiments of the present invention, the anchor 200 comprises a material selected from the group consisting of nitinol, cobalt-chromium alloy, stainless steel, zinc-iron alloy, magnesium alloy, and at least one of polyesters, polycarbonate, and composites thereof. When the anchoring element 200 is made of nitinol or some shape-memory polyesters (e.g., polyurethane), the anchoring element 200 can self-expand, so that the anchoring element 200 can be expanded without a tool (e.g., a balloon), thereby reducing the difficulty of the operation and effectively avoiding damaging the lesion site of the blood vessel. When the anchor 200 is made of another material, the anchor 200 cannot self-expand, and the anchor 200 needs to be expanded by a tool (e.g., a balloon). Of course, the anchoring element 200 may also be made of a material having a shape memory function during the ball-expanding process, so that the anchoring element 200 may have an outward tension to improve the anchoring effect.

In some embodiments of the invention, as shown in fig. 2 to 5, at least one supporting element 400 is connected between two adjacent anchoring elements 200 at different ends of the covering film 100, the supporting element 400 being located inside the covering film 100. The support 400 may also assist in distracting the cover film 100 during distraction of the cover film 100 by the anchor 200. This support 400 not only reduces the amount of radial collapse of the cover 100, but may also reduce the amount of axial retraction of the stent.

Alternatively, the supporting member 400 may be made of the same material as the anchoring member 200, or may be made of a different material. The support members 400 may be distributed along the axial direction of the stent for a blood vessel, or may be angled (e.g., 5 °, 10 °, 20 °, etc.) from the axial direction of the stent for a blood vessel. The shape of the support 400 is a straight line, a bent shape, a wave shape, or a spiral shape. The supporting members 400 may be connected to the corresponding anchoring members 200 by fusion welding or integrally molding (e.g., laser cutting).

Alternatively, the support 400 may also be fixed to the middle of the cover film 100. Thus, in the process of expanding the wrapping film 100 by the anchoring member 200, the wrapping film 100 can be effectively driven to expand. Wherein, the supporting member 400 can be fixed in the middle of the covering film 100 by weaving, bonding or fusion welding.

Alternatively, as shown in fig. 4, the length of the supporting member 400 in the axial direction of the stent is greater than the distance between two adjacent anchors 200 at different ends of the cover film 100, so as to support the cover film 100. Thus, the problem that the wrapping film 100 hangs down due to overlong can be solved, and unstable patches with large sizes can be effectively held. Optionally, the length of the supporting member 400 in the axial direction of the stent is 5% to 20% longer than the distance between two adjacent anchoring members 200 at different ends of the covering film 100, for example, 5%, 10%, 15%, 20% longer. With such an arrangement, it is possible to prevent the supporting member 400 from being too tight when the covering film 100 is arched due to too short length, and it is also possible to prevent a gap between the stent and the inner wall of the blood vessel due to too long length of the supporting member 400.

In some embodiments of the invention, as shown in fig. 5, anchors 200 near the ends of cladding film 100 are spaced from cladding film 100 and attached to cladding film 100 using mounting members 500. Thus, the coating rate of the coating film 100 can be reduced, so that cells can better climb to the middle part of the coating film 100, and endothelialization is promoted. Alternatively, mounting member 500 may be in the form of a filament (e.g., a fiber filament) that may be drawn circumferentially at the ends of cover film 100. Of course, in other embodiments of the invention, anchor 200 near the end of cover film 100 may be braided, fusion welded, etc. directly to cover film 100. In application, the connection mode between the anchor 200 and the cover film 100 near the end of the cover film 100 may be selected according to the lesion site and the size of the cover film 100.

Example 1

This embodiment provides a stent for a blood vessel, as shown in fig. 2, which has 2 anchors 200 provided at one end and 3 anchors 200 provided at the other end, and two anchors 200 connected to the same end are connected to each other by a straight connecting member 300. The anchor 200 is made of cobalt-chromium alloy, the anchor 200 is laser-cut into a corrugated shape, and the connecting member 300 is also formed on the anchor 200 by laser cutting. The two adjacent anchoring elements 200 positioned at different ends of the stent are connected with a piece of coating film 100 made of PCL (polycaprolactone) through a weaving and knotting mode, and the thickness of the coating film 100 is 20 microns and is made of electrostatic spinning. Also disposed between two adjacent anchors 200 at different ends of the stent are 4 PLLA (poly-l-lactide) monofilaments, i.e. struts 400, with a diameter of 10 μm, which are equally spaced. The PLLA monofilaments are on the inside of the cover 100 and are used to help support the cover 100 when the stent is open.

Example 2

This embodiment provides a stent for blood vessels, as shown in fig. 3, which is provided with one injection-molded polycarbonate anchor 200 at each end, and a supporting member 400 having a width of 50 μm and a thickness of 10 μm and made of nitinol is connected between the two anchors 200. The supporting member 400 is re-melted and welded to the anchor member 200 by wrapping the anchor member 200 once. The supporting members 400 are in a straight shape and are distributed along the axial direction of the stent, and the length of the supporting members 400 is 5% -20% longer than the distance between the anchoring members 200, so that when the stent is released, the supporting members 400 slightly protrude outwards to tighten the covering film 100 to prevent the covering film from collapsing.

Example 3

This embodiment provides a stent for a blood vessel, as shown in fig. 4, in which 3 anchoring elements 200 are provided at both ends of the stent, and two anchoring elements 200 connected to the same end are fitted together. Between two adjacent anchors 200 at different ends of the stent there are also provided 4 curved supporting members 400. The supporting member 400 and the anchoring member 200 are laser-engraved on the polylactic acid tube. A piece of polylactic acid coating film 100 is connected between two adjacent anchoring elements 200 at different ends of the stent by means of braiding. The molecular weight of the polylactic acid of the anchor 200 is 20 ten thousand or more, which is larger than the molecular weight of the polylactic acid material used for the cover film 100, so that it can provide a sufficient supporting function. The anchor 200 is also notched to increase the holding force.

Example 4

This embodiment provides a stent for a blood vessel, which is provided with one anchor 200 at each end, as shown in fig. 5. A straight supporting member 400 is disposed between the two anchors 200 to increase the supporting effect on the coating film 100, wherein the supporting member 400 and the anchors 200 are made of cobalt-chromium alloy. A covering film 100 made of a mixed material of PCL and PGLA is further connected between the two anchors 200 by means of braiding, wherein the porosity of the covering film 100 is low in the middle and high at both ends, and 5 strands of braided fiber filaments (i.e., the mounting members 500) are pulled out from both ends of the covering film 100 for being fastened to the anchors 200.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.