CN216823777U

CN216823777U - Covered stent

Info

Publication number: CN216823777U
Application number: CN202123287119.6U
Authority: CN
Inventors: 张向阳; 郑会会; 耿冉
Original assignee: Microport Urocare Jiaxing Co Ltd
Current assignee: Microport Urocare Jiaxing Co Ltd
Priority date: 2021-12-24
Filing date: 2021-12-24
Publication date: 2022-06-28
Anticipated expiration: 2031-12-24

Abstract

The utility model provides a covered stent, covered stent include the covered stent body, encircle be provided with the gel film that at least round takes place the inflation under the humidity condition on the outer wall of covered stent body, follow the extending direction of covered stent body, all the total length of gel film is less than the length of covered stent body. The utility model provides a covered stent can solve among the prior art covered stent and take place easily when treatment blood vessel or chamber are narrow or block up to slide and the not good problem of treatment.

Description

Covered stent

Technical Field

The utility model relates to the technical field of medical equipment, in particular to covered stent.

Background

Stenosis or blockage of a blood vessel or a natural orifice usually requires the use of a stent to support the reconstructed orifice, thereby improving or restoring the physiological function of the organ or tissue. The common stents in the market at present are of two types, namely metal bare stents and covered stents.

The traditional metal bare stent is made by weaving superelasticity shape memory alloy wires or stainless steel wires into a hollow cylindrical mesh body with meshes and a specific length, the diameter of the cylindrical mesh body stent is designed to be slightly larger than the inner diameter of a lumen of a blood vessel or other body organs to be subjected to surgical treatment, the length of the cylindrical mesh body stent is designed to be slightly larger than the length of a narrow or blocked section, then the stent is implanted into the narrow or blocked section of the blood vessel or other lumens, and the stent can prop open the narrow or blocked section of the blood vessel or lumen after radial expansion and release due to the elasticity of the stent, so that the function of supporting and reconstructing the lumen is achieved. However, because of the large amount of mesh structures of the metal bare stent, tissues are easy to grow inwards to cause the problem of secondary stenosis or blockage.

To address the above-mentioned problems, stent grafts have been used in the prior art to address the issue of tissue ingrowth. The tectorial membrane stent is based on the original metal bare stent, a layer of polymer membrane is arranged on the inner surface or the outer surface of the metal bare stent to plug the meshes on the stent, and the method solves the problem that the stent is narrow again. However, since the stent is likely to slip relative to the human tissue, the stent is likely to slip out of the initial position over time, i.e., the stent graft is likely to shift.

Aiming at the problem of displacement of the bracket, the products on the market at present are mainly solved by adopting the following schemes. The first scheme is that the size of the end part of one end or two ends of the bracket is enlarged, so that the end part of the bracket is in a bell mouth shape or a mushroom head shape, and the end part of the bracket is fixed on the inner wall of a cavity channel by extruding the inner wall of the cavity channel through the end part of the bracket, thereby achieving the purpose of preventing the bracket from shifting, as shown in figure 1; the second solution works in a similar manner to the first solution, and patent publication EP2821033B1 discloses a solution for preventing stent migration by adjusting the stent structure to form protrusions at positions other than both ends of the stent, by means of "embedding" of the protrusions into the tissue, as shown in fig. 2. Although the two schemes can solve the problem of stent displacement, the expanded section of the stent has larger radial dimension, so that the stent has the problem of high implantation resistance and difficult implantation in the initial stent implantation.

The third solution is to adjust the stent structure, and patent publication No. CN101721267A discloses a solution for preventing stent displacement, in which different parts of the stent in the axial direction have different supporting forces, and the stent forms a wave shape with the tissue contact surface in the axial direction under the same external force, so as to prevent the stent from slipping, as shown in fig. 3. However, the scheme has certain defects, and the rigidity difference between different rigidity parts of the bracket is reduced along with the time, so that the difference of the axial supporting force between the different rigidity parts is reduced, the bracket slippage cannot be counteracted, and the effect of preventing the bracket slippage is not good. In addition, the prior art also has the technical scheme that the stent is adhered to the inner wall of the blood vessel or the cavity by arranging the adhesive on the outer surface of the stent, so that the stent is prevented from sliding, but the scheme weakens the adhesion between the stent and the inner wall of the blood vessel or the cavity due to the degradation of the adhesive, and cannot achieve the effect of preventing the stent from sliding.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a covered stent to solve among the prior art covered stent the problem that slides takes place easily when treatment blood vessel or chamber are narrow or block up.

In order to solve the technical problem, the utility model provides a covered stent, including the covered stent body, encircle be provided with the gel film that at least round takes place the inflation under the humidity condition on the outer wall of covered stent body, follow the extending direction of covered stent body, all the total length of gel film is less than the length of covered stent body.

Furthermore, a plurality of circles of gel films are arranged on the outer wall surrounding the covered stent body and are arranged at intervals along the extending direction of the covered stent body.

Further, the thickness of the multiple circles of gel film may be equal or unequal.

Further, the thickness of the gel film is 50-500 μm.

Further, the gel film is made of sodium acrylate and/or alginate.

Further, the gel film also comprises a medicine. The medicine is used for treating the stenosis or blockage of blood vessels or cavities. The drugs in the multiple circles of gel film are the same or different.

Further, the tectorial membrane stent body comprises a metal bare stent and a tectorial membrane coated on the inner wall and/or the outer wall of the metal bare stent, and the metal bare stent can be a hollow cylindrical net body with meshes.

Further, the material of the metal bare stent is selected from one or more of nickel, titanium, nickel alloy and titanium alloy.

Further, the material of the film is selected from one or a mixture of polyurethane, silica gel and polytetrafluoroethylene.

The utility model also provides a preparation method of covered stent, including following step:

s1: providing a metal bare stent;

s2: coating a film on the inner wall and/or the outer wall of the metal bare stent to obtain a film-coated stent body;

s3: at least one ring of gel film is coated around the outer wall of the stent graft body.

To sum up, compare with prior art, the utility model provides a covered stent has following advantage:

the utility model discloses a tectorial membrane support is before not implanting, and the thickness of the outstanding tectorial membrane support body outer wall of gel film is very little, and at the implantation in-process of tectorial membrane support, gel material can not inhale at once and take place obvious inflation fully liquid, and this just makes tectorial membrane support when implanting blood vessel or other cavitys, can not lead to tectorial membrane support to implant the difficulty because of obvious radial thickness difference. After the covered stent is implanted into a proper position in a blood vessel or a cavity of a human body, the volume of a gel material in a gel film can gradually expand after contacting a corresponding solvent (such as blood in the blood vessel and body fluid in the cavity), and finally an obvious bulge is formed on the outer surface of the stent body.

Furthermore, the utility model discloses a gel film can also bear the weight of the medicine in the tectorial membrane support, and after the gel material inflation, the medicine can slowly release from the gel material, plays corresponding treatment, promptly the utility model discloses a tectorial membrane support can realize preventing the purpose that the support shifted after implanting, can also play the effect of release medicine cooperation treatment simultaneously.

Drawings

FIG. 1 is a schematic view of a stent graft;

FIG. 2 is a schematic structural view of another stent graft;

FIG. 3 is a schematic structural view of yet another stent graft;

FIG. 4 is a schematic structural view of a stent graft according to an embodiment of the present invention;

FIG. 5 is a schematic view of an expanded gel material of a stent graft in accordance with one embodiment of the present invention;

FIG. 6 is a schematic structural view of a stent graft according to another embodiment of the present invention;

FIG. 7 is a schematic view of another embodiment of the present invention showing the expanded gel material in the stent graft;

FIG. 8 is a cross-sectional view of a stent graft according to another embodiment of the present invention;

FIG. 9 is a schematic cross-sectional view of a stent graft according to an embodiment of the present invention;

FIG. 10 is a flow chart of a method for manufacturing a stent graft according to an embodiment of the present invention.

Wherein the reference numbers are as follows:

10-a stent graft body; 20-gel film; 11-bare metal stent; 12-coating.

Detailed Description

The stent graft provided by the present invention will be described in further detail with reference to the accompanying drawings and the following detailed description. The advantages and features of the present invention will become more apparent from the following description.

It is to be noted that the drawings are in a very simplified form and are not to precise scale, which is merely for the purpose of facilitating and distinctly claiming the embodiments of the present invention. To make the objects, features and advantages of the present invention more comprehensible, please refer to the attached drawings. It should be understood that the structure, ratio, size and the like shown in the drawings attached to the present specification are only used for matching with the content disclosed in the specification, so as to be known and read by those skilled in the art, and are not used for limiting the limitation of the implementation of the present invention, so that the present invention does not have the essential significance in the technology, and any modification of the structure, change of the ratio relationship or adjustment of the size should still fall within the scope of the technical content disclosed in the present invention without affecting the function and the achievable purpose of the present invention.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "axial", "radial", "circumferential", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of description and simplicity of description, and do not indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore should not be construed as limiting the present invention.

In this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.

In order to realize the above idea, the utility model provides a covered stent, as shown in fig. 4 and 5, including covered stent body 10, encircle be provided with the gel film 20 that at least round can take place the inflation under the humidity condition on the outer wall of covered stent body 10, gel film 20 is made by gel material, follows the extending direction of covered stent body 10, all the length of medicine carrying film 20 is less than the length of covered stent body 10, gel material that gel film chooseed for use can be elastic gel material, and the volume can take place the inflation when this kind of gel material contacts corresponding dispersion medium (for example water). The gel film can be made of sodium acrylate and/or alginate, and the gel material has good biocompatibility, can be in long-term contact with human tissues without side effect, has strong expansion capacity and has certain physical hardness after expansion.

In the scheme of this embodiment, set up at least round gel film 20 on the outer wall of covered stent body 10, contain gel material in the gel film 20, compare with horn mouth, mushroom head type among the prior art or other bellied supports that have, the utility model discloses a covered stent before not implanting, the thickness of the outstanding covered stent body outer wall of gel film is very little, and at covered stent's implantation in-process, gel material can not inhale at once and take place obvious inflation, and this just makes covered stent when implanting blood vessel or other cavitys, can not lead to covered stent to implant the difficulty because of obvious radial thickness difference. After the covered stent is implanted into a proper position in a blood vessel or a cavity of a human body, the volume of a gel material in a gel film can gradually expand after contacting a corresponding solvent (such as blood in the blood vessel and body fluid in the cavity), and finally an obvious bulge is formed on the outer surface of the stent body.

In order to make the utility model discloses a covered stent's anti-displacement effect is better, the winding in this embodiment be provided with many circles of gel film 20 on covered stent body 10's the outer wall, many circles of gel film 20 are followed covered stent body 10's extending direction interval sets up, and many circles of gel film 20 can form a plurality of protruding structures on the outer wall after covered stent implants, play the better effect of preventing shifting.

In addition, gel film can also bear the weight of the medicine in this embodiment and after the gel material inflation, the medicine can slowly release from the gel material, plays corresponding treatment, promptly the utility model discloses a covered stent can realize preventing the purpose that the support shifted after implanting, can also play the effect of releasing medicine cooperation treatment simultaneously. Preferably, the medicament is a medicament for treating stenosis or blockage of a blood vessel or lumen.

Further, in another embodiment of the present invention, the thickness of the multiple circles of gel film 20 may be equal or unequal, and the drugs carried in the multiple circles of gel film 20 may be the same or different. The thickness of the multi-circle gel film 20 can be set to be equal, so that the batch production is convenient, the multi-circle gel film 20 can be set to be different, the heights of the protruding structures formed by the expansion of the gel films 20 with different thicknesses after the implantation can be different, so that different positions of the film-coated support in the axial direction have different supporting forces, and the anti-displacement effect is better. Similarly, the multiple circles of gel film 20 may carry the same or different drugs, and the combination of different drugs may provide better therapeutic effect. Wherein, the drug in the gel film 20 of the present invention can be a drug for treating stenosis or blockage of blood vessel or lumen, for example, the drug can be rapamycin, paclitaxel, etc., so that the stent graft is used for physically expanding the stenosis section of blood vessel or lumen, thereby achieving better treatment effect on stenosis or blockage of blood vessel or lumen.

The utility model discloses an in the scheme, the main part material of gel film mainly is gel material, and the thickness of gel film is highly relevant with the bellied that forms after the gel material inflation, can set up suitable gel film thickness according to the size of the narrow section or the jam section in the blood vessel of implanting or the chamber way, reaches better preventing the effect of shifting. Preferably, in the stent graft of the present invention, the thickness of the gel film is 50 to 500 μm.

In addition, the content of the drug carried in the gel film can be set according to the needs, the drug is mixed in the gel material, and the drug-carrying amount of the drug in the gel film can be set according to the solubility and the dispersibility of the drug, the release rate and the absorption efficiency of the drug after the gel material swells in a human body, and the like.

In the embodiment of the present invention, as shown in fig. 8 and 9, the stent graft body 10 includes a bare metal stent 11 and a coating film 12 coated on the inner wall and/or the outer wall of the bare metal stent 11, the bare metal stent 11 may be a hollow cylindrical mesh body with meshes. The utility model discloses a covered stent can have multiple morphological structure according to tectorial membrane 12's coating position. When the coating 12 is coated on the inner wall of the bare metal stent 11, as shown in fig. 6, 7 and 9, the coated stent is composed of the gel film 20, the bare metal stent 11 and the coating 12 from the outside to the inside in sequence. As shown in fig. 8, when the coating 12 is coated on the outer wall of the bare metal stent 11, the coating stent is composed of a gel film 20, the coating 12 and the bare metal stent 11 from the outside to the inside in sequence. In the same way, when the coating is simultaneously coated on the outer wall and the inner wall of the bare metal stent 11, the coated stent sequentially comprises the gel film 20, the coating 12, the bare metal stent 11 and the coating 12 from outside to inside.

Further, the material 1 of the bare metal stent 1 may be one or more selected from nickel, titanium, nickel alloy and titanium alloy. The material of the coating 12 is selected from one or a mixture of polyurethane, silica gel and polytetrafluoroethylene.

The utility model also provides a preparation method of covered stent, as shown in FIG. 10, including the following steps:

s1: providing a bare metal stent 11;

s2: coating a film 12 on the inner wall and/or the outer wall of the bare metal stent 11 to obtain a film-coated stent body 10;

s3: and coating at least one circle of gel film 20 around the outer wall of the covered stent body 10 to obtain the covered stent.

the utility model discloses a tectorial membrane support is before not implanting, and the thickness of the outstanding tectorial membrane support body outer wall of gel film is very little, and at tectorial membrane support's implantation in-process, the gel material can not inhale at once and take place obvious inflation with liquid, and this just makes tectorial membrane support when implanting blood vessel or other cavitys, can not lead to tectorial membrane support to implant the difficulty because of obvious radial thickness difference. After the covered stent is implanted into a proper position in a blood vessel or a cavity of a human body, the volume of a gel material in a gel film can gradually expand after contacting a corresponding solvent (such as blood in the blood vessel and body fluid in the cavity), and finally an obvious bulge is formed on the outer surface of the stent body.

The above description is only for the description of the preferred embodiments of the present invention, and not for any limitation of the scope of the present invention, and any modification and modification made by those skilled in the art according to the above disclosure are all included in the protection scope of the claims. It will be apparent to those skilled in the art that various changes and modifications may be made to the present invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims and their equivalents, the present invention is also intended to include such modifications and variations.

Claims

1. The covered stent comprises a covered stent body and is characterized in that at least one circle of gel film which expands under the humidity condition is arranged on the outer wall surrounding the covered stent body, and the total length of all the gel films is smaller than the length of the covered stent body along the extending direction of the covered stent body.

2. The stent graft of claim 1, wherein a plurality of turns of the gel film are disposed around an outer wall of the stent graft body, the plurality of turns of the gel film being spaced apart along a direction of elongation of the stent graft body.

3. The stent graft of claim 2, wherein the plurality of turns of gel film are of equal thickness.

4. The stent graft of claim 2, wherein the plurality of turns of the gel film are of unequal thickness.

5. The stent graft as recited in claim 1, wherein said gel film has a thickness of 50-500 μm.

6. The stent graft of claim 1, wherein the stent graft body comprises a bare metal stent and a coating coated on the inner and/or outer wall of the bare metal stent.