CN110664522A

CN110664522A - Stent for implantation into a blood vessel

Info

Publication number: CN110664522A
Application number: CN201810621782.9A
Authority: CN
Inventors: 赫明; 龚霄雁; 魏继昌
Original assignee: SUZHOU INNOMED MEDICAL DEVICE Co Ltd
Current assignee: SUZHOU INNOMED MEDICAL DEVICE Co Ltd
Priority date: 2018-06-15
Filing date: 2018-06-15
Publication date: 2020-01-10

Abstract

The invention provides a stent for being implanted into a blood vessel, which comprises a stent body, wherein the pore density of the stent body is 12.7PPI-1270PPI, and the stent is a dense-mesh stent, so that dense meshes can better isolate lesion plaques in the blood vessel and can not block the blood supply of branch blood vessels.

Description

Stent for implantation into a blood vessel

Technical Field

The invention relates to a stent for implanting into a blood vessel, in particular to a dense mesh stent.

Background

In recent years, the minimally invasive intracavity treatment technology of vascular surgery has made great progress, and the vascular stent is widely applied to the treatment of systemic vascular diseases at present. According to different lesion distributions, different vascular stents can be mainly applied to peripheral vascular lesions, arteriolar lesions, aortic lesions, venous lesions and the like; according to different pathologies, different vascular stents can be used for traumatic lesions of blood vessels, stenotic or restenotic lesions of blood vessels, etc.

With the development of the intracavity treatment technology and the use of various intracavity implant interventional devices, the advantages and the disadvantages of the existing stent are gradually exposed, and the clinical requirements on the stent are different according to the symptoms. For plaque type angiostenosis, a stent is required to have a good blocking effect, and the plaque is prevented from continuously increasing and falling off to cause other diseases. For vascular aneurysm, a stent is needed to isolate a tumor body or a false cavity, the blood flow direction is changed, and the stent is needed to have good flexibility and fatigue resistance for an active part. The pipe diameter of the delivery system is required to be as small as possible in the aspect of stent delivery, and the influence on vascular stimulation and normal blood flow is avoided.

Disclosure of Invention

The invention aims to provide the vascular stent which has good flexibility and adherence, can well isolate a diseased part and has small influence on blood flow of a branch vessel adjacent to the diseased part.

In order to achieve the above object, the vascular stent of the present invention comprises: a stent body having a pore density of 12.7PPI-1270 PPI. For example, the stent body has a pore density of 26PPI-49PPI or 255PPI-1270 PPI.

In some embodiments of the invention, the stent further comprises a cover at least partially covering the stent body, the cover being disposed inside and/or outside the stent body. For example, the cover may be provided at one or both ends or all of the stent body. For example, the length of the cover film is 20% -60% of the length of the stent body. The covering film is a polyester film, a PTFE film, a woven dense net or a high polymer material microporous film. The pore density of the woven dense net is greater than that of the stent body; the aperture of the high polymer material microporous membrane is 0.01mm-2 mm. The pore density of the portion of the stent body covered by the cover is less than the pore density of the portion not covered by the cover.

In some embodiments of the invention, the stent body is woven from at least one woven wire or cut from a laser. The bracket body is a cylindrical, conical, sugarcoated haw-shaped or two-side bell mouth-shaped tubular bracket. The cross section of the knitting silk is circular, oval, trapezoidal, rhombic and rectangular. The filament diameter of the braided filaments is 0.001 inches to 0.05 inches.

Compared with the prior art, the invention has the following advantages:

the stent body has larger pore density and smaller pores, so that the plaque can be well isolated when the stent is used for plaque type angiostenosis; when the blood vessel aneurysm applying agent is used for the blood vessel aneurysm, a tumor body or a false cavity can be well isolated, the hemodynamics of a lesion part is changed, the impact of blood flow on the lesion part is weakened, the blood flow of adjacent branch blood vessels is slightly influenced, and the branch blood vessels cannot be occluded.

When the dense-mesh stent is at least partially covered with the covering film, the dense-mesh stent has better anti-migration performance compared with a full-covering stent, and the covering film part is equivalent to a dense-mesh stent body and has better blocking effect on blood flow.

When the stent body is formed by weaving woven wires, the woven structure has good ductility and better flexibility, can better adapt to a vascular structure, accords with human vascular anatomy, and can enable a stent delivery sheath of a delivery stent to have a smaller pipe diameter.

The stents with different structures and shapes can adapt to different vascular structures and have better positioning effect.

The blood vessel stent can be used for peripheral blood vessels or nerve vessels and the like, has good flexibility and adherence, can well isolate diseased regions, change the hemodynamics of tumor bodies or false cavities, weaken the impact of blood flow on the diseased regions, has small influence on the blood flow of branch blood vessels adjacent to the diseased regions, and is suitable for complex diseased regions.

The technical solutions of the present invention and the advantages thereof will be described in further detail below with reference to the accompanying drawings and the detailed description.

Drawings

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

fig. 2 is a schematic structural view of another example of a stent for implantation into a blood vessel according to embodiment 1 of the present invention;

fig. 3 is a schematic structural view of still another example of a stent for implantation into a blood vessel according to embodiment 1 of the present invention;

fig. 4 is a schematic structural view of still another example of a stent for implantation into a blood vessel according to embodiment 1 of the present invention;

fig. 5 is a schematic structural view of still another example of a stent for implantation into a blood vessel according to embodiment 1 of the present invention;

fig. 6 is a schematic structural view of an example of a stent for implantation in a blood vessel according to embodiment 2 of the present invention;

fig. 7 is a schematic structural view of another example of a stent for implantation into a blood vessel according to embodiment 2 of the present invention;

fig. 8 is a schematic structural view of still another example of a stent for implantation into a blood vessel according to embodiment 2 of the present invention;

fig. 9 is a schematic structural view of still another example of a stent for implantation into a blood vessel according to embodiment 2 of the present invention.

Detailed Description

Various aspects of the invention are described in detail below with reference to the figures and the detailed description. The components in the figures are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the invention.

In various embodiments of the present invention, well-known structures or materials are not described in detail. Furthermore, the described features, structures, or characteristics of the invention may be combined in any suitable manner in one or more embodiments. Furthermore, it will be understood by those skilled in the art that the following embodiments are illustrative only and are not intended to limit the scope of the present invention. Those of ordinary skill in the art will appreciate that the components of the various embodiments described herein and illustrated in the figures may be arranged and designed in a wide variety of different configurations or proportions. Technical terms not specifically described in the present specification should be construed in the broadest sense in the art unless otherwise specifically indicated.

[ embodiment 1 ]

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

As shown in fig. 1, the stent provided by the present embodiment includes a stent body 100 having a cylindrical tubular shape and the same diameter throughout the stent body, and the pore density (average number of pores per inch in length, in PPI) of the stent body is 40PPI uniformly, which is suitable for providing sufficient support force to prevent the stent from shifting in the blood vessel, and has good flexibility and adherence, and good isolation of the lesion site (e.g., plaque or tumor body).

The stent body 100 is integrally formed by weaving 6 pieces of knitting yarns of the same specification, the yarn diameter of the knitting yarns is 0.01 inch, and the cross section of the knitting yarns is circular. The stent with the braided structure has good flexibility, can better adapt to the vascular structure and conforms to the anatomy of human blood vessels.

Fig. 2 is a schematic structural view of another example of a stent for implantation into a blood vessel according to embodiment 1 of the present invention. In this embodiment, as shown in fig. 2, the difference is that the stent is shaped to be tapered to better conform to the shape characteristics of the body vessel (e.g., carotid artery vessel) at the implantation site, as compared to the embodiment shown in fig. 1.

Fig. 3 is a schematic structural view of still another example of a stent for implantation into a blood vessel according to embodiment 1 of the present invention. As shown in fig. 3, in the present embodiment, compared to the embodiment shown in fig. 1, the difference is that the stent is shaped as a sugarcoated haws shape, which has better positioning effect after being implanted into a blood vessel (such as popliteal artery), and prevents the stent from being displaced.

Fig. 4 is a schematic structural view of still another example of a stent for implantation into a blood vessel according to embodiment 1 of the present invention. In this embodiment, as shown in fig. 4, the difference is that the stent has a branch stent to better adapt to the shape characteristics of the branch vessel, compared with the embodiment shown in fig. 1.

Fig. 5 is a schematic structural view of still another example of a stent for implantation into a blood vessel according to embodiment 1 of the present invention. As shown in fig. 5, in the present embodiment, compared to the embodiment shown in fig. 1, the difference is that the stent is shaped as a two-sided trumpet, which has better positioning effect after being implanted into a blood vessel (such as iliac artery), and prevents the stent from being displaced.

In other embodiments according to embodiment 1, the pore density of the stent body 100 may be 255PPI uniformly, and the stent body of this embodiment has smaller pores and better barrier effect on the lesion site compared to the stent body having a pore density of 40 PPI.

Optionally, the pore density of the stent body may also be any other value between 12.7PPI-1270PPI, such as 26PPI-49PPI or 255PPI-1270PPI, such as 100PPI, 200PPI, 300PPI, 400PPI, 500PPI, 600PPI, 700PPI, 800PPI, 900PPI, 1000PPI, 1100PPI, 1200PPI, and so forth.

Further, in the present embodiment, the holder body may also be integrally cut by laser; or is made by winding braided wires; the number of the braided wires can be 1 or 2, 3, 4, 5 or more; the cross section of the braided wire can be circular, oval, trapezoidal, rhombic and rectangular, and the diameter of the wire can be any value between 0.001 inch and 0.05 inch; the stent body can be formed by weaving different sizes of weaving wires in a mixed way; the stent may be made of one or more of nickel-titanium alloy, L605 cobalt-chromium alloy, 304 stainless steel, 316L stainless steel, MP35N alloy, and the like.

[ embodiment 2 ]

Fig. 6 is a schematic structural view of an example of a stent for implantation into a blood vessel according to embodiment 2 of the present invention. As shown in fig. 6, the stent provided by the present embodiment includes a stent body 200 and a cover 201.

Wherein the stent body 200 has a cylindrical tubular shape, the entire stent body has the same diameter, and the pore density (average number of pores per inch in length, unit is PPI) of the stent body is uniformly 100 PPI.

The cover 201 is provided at one end of the stent body, covering the outer surface of the stent body. The total length of the stent body 200 is 20mm, and the length of the covering membrane 201 accounts for 50% of the length of the stent body 200.

Fig. 7 is a schematic structural view of another example of a stent for implantation into a blood vessel according to embodiment 2 of the present invention. As shown in fig. 7, the present embodiment differs from the embodiment shown in fig. 6 in that the stent body is provided with a cover 201 at the middle portion thereof, and the stent body does not have covers at both ends thereof. At this time, the total length of the stent body 200 is 20mm, and the length of the stent cover 201 may occupy 30% of the length of the stent body 200.

Fig. 8 is a schematic structural view of still another example of a stent for implantation into a blood vessel according to embodiment 2 of the present invention. As shown in fig. 8, in the present embodiment, the difference with respect to the embodiment shown in fig. 6 is that the stent body is provided with the coatings 201 at both end portions thereof, and the stent body does not have a coating in the middle. At this time, the total length of the stent body 200 is 20mm, the length of the covering films 201 at both ends can occupy 60% of the length of the stent body 200 altogether, and the length of the covering films 201 at both ends may be the same or different.

In addition, in the present embodiment, the coating may be a dacron film, a PTFE film, a woven dense mesh or a polymer microporous film, and the coating may cover the whole stent body or may cover a part of the stent body, for example, one coating may be covered and one non-coating may be covered, for example, the length of the coating may be 20% to 60% of the length of the stent body; the braided dense net refers to a braided net layer braided by braided wires, the pore density of the braided net layer is greater than that of the stent body and can be in the range of 12.7PPI to 1270PPI, and the material of the braided net layer can comprise at least one of chromium-cobalt alloy, stainless steel, high polymer material and biodegradable material; the polymer microporous membrane herein has a pore diameter of 0.01mm to 2mm, as shown in FIG. 9, for example.

For example, in other embodiments according to this embodiment, the stent body 200 may have a uniform pore density of 25PPI, and the covered covering film is a braided dense mesh 201 having a pore density of 500PPI, which is a composite structure of the stent body and the braided dense mesh, the braided dense mesh serves to block the lesion, and the stent body provides support for the braided dense mesh, stabilizing the structure.

For example, in other embodiments according to the present embodiment, the pore density of the stent body 200 may be uniform to 1000PPI, and the covered covering film is the braided dense mesh 201 with a pore density of 1200PPI, so that the composite structure of the stent body and the braided dense mesh has smaller pores and better barrier effect to the lesion site.

In addition, in this embodiment, the stent body may be any one of the foregoing embodiments 2, and will not be described herein again.

In addition to the case where the stent body is coated with the coating film in the embodiment shown in fig. 6 to 9, in the present embodiment, the coating film may be coated on the inner surface of the stent body, or coated on the inner surface and the outer surface of the stent body.

In addition to the position of the stent graft in the embodiment shown in fig. 6 to 9, in the present embodiment, the stent graft may cover the entire stent body, or may cover a part of an arbitrary position of the stent body, for example, one stent graft may not cover the stent graft.

Further, in the present embodiment, in addition to having a uniform pore density, the stent body may be configured such that the pore density of the portion covered with the coating is smaller than the pore density of the portion not covered with the coating, for example, the pore density of the portion covered with the coating is 800PPI, the pore density of the portion not covered with the coating is 1000PPI, or the like.

The intravascular stent has good flexibility and adherence, can well isolate a diseased part, change the hemodynamics of a tumor body or a false cavity, weaken the impact of blood flow on the diseased part, has small influence on the blood flow of a branch vessel adjacent to the diseased part, and is suitable for complex diseased parts.

The terms and expressions used in the specification of the present invention have been set forth for illustrative purposes only and are not meant to be limiting. It will be appreciated by those skilled in the art that various changes in the details of the above-described embodiments may be made without departing from the spirit of the invention. The scope of the invention is, therefore, indicated by the appended claims, in which all terms are to be understood in their broadest reasonable sense unless otherwise indicated.

Claims

1. A stent for implantation in a blood vessel, the stent comprising a stent body having a pore density of 12.7PPI-1270 PPI.

2. The stent of claim 1, further comprising a cover at least partially covering the stent body, the cover being disposed inside and/or outside the stent body.

3. The stent of claim 2, wherein the cover is disposed at one or both ends or all of the stent body.

4. The stent of claim 2, wherein the length of the cover is 20% to 60% of the length of the stent body.

5. The stent of claim 2, wherein the cover membrane is a dacron membrane, a PTFE membrane, a woven dense mesh, or a microporous membrane of a polymeric material.

6. The stent of claim 5, wherein the woven dense mesh has a pore density greater than the pore density of the stent body; the aperture of the high polymer material microporous membrane is 0.01mm-2 mm.

7. The stent of claim 2, wherein a portion of the stent body covered by the cover has a pore density that is less than a pore density of a portion not covered by the cover.

8. The stent of claim 1, wherein the stent body has a pore density of 26PPI-49PPI or 255PPI-1270 PPI.

9. A stent according to any one of claims 1 to 8, wherein the stent body is woven from at least one braided wire or cut by laser.

10. The stent of claim 9, wherein the stent body is a cylindrical, conical, sugarcoated or double-sided flared tubular stent.

11. The stent of claim 9, wherein the braided wires are circular, oval, trapezoidal, diamond-shaped, and rectangular in cross-section.

12. The stent of claim 9, wherein the braided filaments have a filament diameter of 0.001 inches to 0.05 inches.