CN114948334A

CN114948334A - Pulmonary artery tectorial membrane support

Info

Publication number: CN114948334A
Application number: CN202210375242.3A
Authority: CN
Inventors: 江森; 虞栋; 揭冰; 李玲玲; 马旭; 周而辰; 李家威; 李志刚; 王国辉
Original assignee: Shanghai Weilang Medical Technology Co ltd
Current assignee: Shanghai Pulmonary Hospital (shanghai Occupational Disease Prevention And Treatment Institute)
Priority date: 2022-04-11
Filing date: 2022-04-11
Publication date: 2022-08-30

Abstract

The invention provides a pulmonary artery covered stent. The pulmonary artery covered stent comprises a bare stent and a covered membrane, wherein the bare stent comprises a plurality of supporting beams and a plurality of connecting beams, and the connecting beams are connected with two adjacent supporting beams so as to connect the supporting beams into a net-shaped tubular structure; the covering film comprises an outer film and an inner film, the outer film and the inner film are respectively arranged on the outer surface and the inner surface of the bare stent, and two ends of the bare stent are exposed out of the outer film and the inner film; the pulmonary artery covered stent is formed into a conical stent in an expansion mode, and the length of the support beams is gradually increased along the direction from one end of the bare stent to the other end of the bare stent in the axial direction of the bare stent. The pulmonary artery covered stent disclosed by the invention is more suitable for the characteristics of pulmonary arteries, can be better and completely attached to the neck of a tumor, namely has better adherence and is not easy to cause internal leakage. And moreover, the flexibility and the elasticity are good, and the effectiveness of the film covering is enhanced.

Description

Pulmonary artery tectorial membrane support

Technical Field

The invention belongs to the technical field of medical equipment, and particularly relates to a pulmonary artery covered stent.

Background

The pulmonary artery is sent from the right ventricular pulmonary artery cone to the lower part of the aortic arch, divides the left and right pulmonary arteries, participates in conveying venous blood to the lung, and is an important passage in the systemic pulmonary circulation. In recent years, more and more attention has been paid to the clinical application of the pulmonary artery organic lesions caused by benign and malignant occupancy of the various hilum and mediastinum. It can be classified into ischemic lesion and hemorrhagic lesion according to the types of lesions.

Among the devices on the market, there is no stent graft dedicated to the pulmonary artery. At present, FLUNEENCY covered stents of a certain company and VIABAHN heparin-coated covered stents of a certain company are most commonly used in clinic. However, both of these two commonly used stent grafts are designed in a straight tube shape, and the size of the tube diameter consistency between the front and the back is not very suitable for the pulmonary artery, and the following problems are also existed: the covered stent can not completely fit the neck of a tumor in a tortuous blood vessel, i.e. the adherence is poor and internal leakage is easy to cause; the pulmonary artery stent has small effective diameter and poor flexibility, and cannot be applied to wider and bent pulmonary artery vessels; the stent body of the covered stent is limited by the covered membrane, the flexibility and the flexibility are poor, the covered membrane is easy to wrinkle, crack and the like, and the effectiveness of the covered membrane is influenced.

Therefore, there is a need to provide an improved solution to the above-mentioned deficiencies of the prior art.

Disclosure of Invention

The invention aims to provide a pulmonary artery covered stent, which aims to solve the problems of poor adherence, poor flexibility and influence on the effectiveness of a covered membrane of the conventional pulmonary artery covered stent.

In order to achieve the above purpose, the invention provides the following technical scheme:

a pulmonary artery stent graft, comprising:

a bare stent including a plurality of support beams and a plurality of connection beams connecting adjacent two of the support beams to connect the plurality of support beams into a mesh-like tubular structure;

the covered membrane comprises an outer membrane and an inner membrane, the outer membrane and the inner membrane are respectively arranged on the outer surface and the inner surface of the bare stent, and two ends of the bare stent are exposed out of the outer membrane and the inner membrane;

the pulmonary artery covered stent is formed into a conical stent in an expansion mode, and the length of the supporting beams is gradually increased along the direction from one end of the bare stent to the other end of the bare stent in the axial direction of the bare stent.

Optionally, the supporting beams are provided with a supporting unit, two adjacent supporting beams are connected by one connecting beam, and the connecting beams are arranged in a staggered manner in the axial direction of the bare bracket; or, the supporting beam has two the supporting unit, adjacent two adopt two between the supporting beam the tie-beam is connected, two the tie-beam corresponds respectively to be connected in two the supporting unit, just in the axis direction of naked support, it is a plurality of the tie-beam is dislocation set.

Optionally, the support unit includes a plurality of support tubes and a plurality of arc support portions that are alternately connected, the arc support portions of two adjacent support beams are arranged in a staggered manner, and two ends of the connecting beam are respectively connected to the two arc support portions in a staggered manner; the number of the supporting tubes is 10-15, and the length expansion rate of the supporting tubes is 10-20%.

Optionally, the inner-outer circular arc diameter ratio of the circular arc supporting part is 1: 2; and/or the included angle formed by two adjacent supporting pipes is 50-70 degrees in the expansion state.

Optionally, the connecting beam is in an S-shaped structure, an omega-shaped structure or a corrugated structure; and/or, in the axial direction of the bare stent, the length of the connecting beam is 1/4-1/3 of the length of the supporting beam.

Optionally, the diameter of the formed tapered stent after the pulmonary artery covered stent is expanded is 15-17 mm.

Optionally, the bare stent is made of a tube, the wall thickness of the tube is 0.1-0.2mm, and the outer diameter of the tube is 2.5-3 mm; and/or the bare stent is made of one of stainless steel, cobalt-based alloy, platinum-iridium alloy, nickel-titanium alloy and magnesium-based alloy.

Optionally, the outer membrane is two layers of PTFE membranes, the inner membrane is one layer of PTFE membrane, and the outer membrane and the inner membrane are respectively and fixedly connected to the outer surface and the inner surface of the bare stent in a hot-pressing manner.

Optionally, both ends of the bare stent are provided with image points.

Optionally, both ends of the bare stent are flared after expansion.

Has the beneficial effects that:

the pulmonary artery covered stent is formed into a conical stent structure after being expanded, wherein the length of the supporting beam is gradually changed, so that the pulmonary artery covered stent is more suitable for the characteristics of pulmonary arteries, can be better and completely attached to the neck of a tumor, has better adherence and is not easy to cause internal leakage. And moreover, the bare stent adopts an open structural design, the flexibility and the flexibility of the covered stent after the bare stent is covered with the film are good, and the effectiveness of the film covering is enhanced. Meanwhile, after the film is coated, the bare stent can be isolated from the blood vessel environment, and intimal hyperplasia caused by the stimulation of the blood vessel by the metal bare stent is avoided, so that the restenosis in the pulmonary artery covered stent is effectively prevented.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification, illustrate exemplary embodiments of the invention and together with the description serve to explain the invention and not to limit the invention. Wherein:

FIG. 1 is a schematic structural view of a pulmonary artery stent graft according to one embodiment of the present invention;

FIG. 2 is a cross-sectional view of a pulmonary artery stent graft according to an embodiment of the invention;

FIG. 3 is a schematic structural view of a bare stent in a contracted state according to one embodiment of the invention;

FIG. 4 is a schematic view of a portion of the structure of FIG. 3 at A;

FIG. 5 is a schematic view of the structure of FIG. 3 after being unfolded and rotated 90 degrees at A;

FIG. 6 is a schematic view of a portion of the structure shown at B in FIG. 3;

FIG. 7 is a schematic view of the structure of FIG. 3 after being unfolded and rotated 90 degrees at B;

FIG. 8 is a schematic view of a portion of the structure of FIG. 3 at C;

FIG. 9 is a schematic view of the structure of FIG. 3 after being unfolded and rotated 90 degrees at C;

FIG. 10 is a schematic view of the bare stent of FIG. 3 after the end has been deployed and rotated 90;

FIG. 11 is a schematic structural view of a bare stent in a contracted state according to another embodiment of the invention;

FIG. 12 is a schematic view of a portion of the structure of FIG. 11 at A;

FIG. 13 is a schematic view of the structure of FIG. 11 after being unfolded and rotated 90 at A;

FIG. 14 is a schematic view of a portion of the structure of FIG. 11 at B;

FIG. 15 is a schematic view of the structure of FIG. 11 after being unfolded and rotated 90 degrees at B;

FIG. 16 is a schematic view of a portion of the structure of FIG. 11 at C;

fig. 17 is a schematic view of the structure of fig. 11 after being unfolded and rotated by 90 °.

Reference numbers in the figures: 100-pulmonary artery stent graft; 1-bare stent; 11-a support beam; 11 a-a support unit; 111-a support tube; 112-arc support; 12-a connecting beam; 2, covering a film; 21-outer membrane; 22-inner membrane; 3-image point; 4-bell mouth.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely below, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments that can be derived by one of ordinary skill in the art from the embodiments given herein are intended to be within the scope of the present invention.

The present invention will be described in detail with reference to examples. It should be noted that the embodiments and features of the embodiments may be combined with each other without conflict.

Aiming at the problems of the existing pulmonary artery covered stent, the invention provides a pulmonary artery covered stent 100, the pulmonary artery covered stent 100 comprises a metal bare stent 1 and a covering film 2 covering the inner surface and the outer surface of the metal bare stent 1, after covering, the metal bare stent 1 can be isolated from the blood vessel environment, the hyperplasia of intima 22 caused by the stimulation of the blood vessel by the metal bare stent 1 is avoided, and the restenosis in the pulmonary artery covered stent 100 is effectively prevented.

The pulmonary artery covered stent 100 is formed into a conical stent structure after expansion, wherein the length of the supporting beam 11 adopts a gradual change design, so that the pulmonary artery covered stent is more suitable for the characteristics of pulmonary arteries and can be better and completely attached to the neck of a tumor, namely, has better adherence. The bare stent 1 adopts an open structural design, the flexibility and the flexibility of the covered stent after the bare stent 1 is covered with the film are good, and the effectiveness of the film 2 is enhanced.

As shown in fig. 1 to 3, in an embodiment of the present invention, a pulmonary artery covered stent 100 includes a bare stent 1 and a covered stent 2, the bare stent 1 includes a plurality of supporting beams 11 and a plurality of connecting beams 12, the supporting beams 11 are wave-shaped and enclose to form a cylindrical structure, and the connecting beams 12 connect two adjacent supporting beams 11 to connect the supporting beams 11 to form a mesh-like tubular structure. As shown in fig. 2, after the plurality of support beams 11 are connected by the plurality of connecting beams 12 to form a net-tube structure, the pulmonary artery stent graft 100 will have a circular ring shape when viewed in the axial direction, that is, it has opposite inner and outer surfaces, wherein the outer surface is a surface adjacent to the inner wall of the blood vessel when in use. The covering film 2 comprises an outer film 21 and an inner film 22, the outer film 21 and the inner film 22 are respectively arranged on the outer surface and the inner surface of the bare stent 1, and two ends of the bare stent 1 are exposed out of the outer film 21 and the inner film 22; that is, the outer membrane 21 and the inner membrane 22 are both open at both ends and closed in the middle. That is, the pulmonary artery stent graft 100 of the present invention has a lumen structure with openings at both ends, and the lumen thereof constitutes a blood flow channel. The pulmonary artery covered stent 100 is expanded to form a conical stent, namely, in an expanded state, the bare stent 1, the inner membrane 22 and the outer membrane 21 are all in a conical structure; in the contracted state, the bare stent 1, the inner membrane 22 and the outer membrane 21 are all cylindrical structures. Defining the bare stent 1 to have a proximal end and a distal end, the length of the plurality of support beams 11 gradually increases in the direction from one end (i.e., the proximal end) to the other end (the distal end) of the bare stent 1 in the axial direction of the bare stent 1, as shown in fig. 4 to 10, and 12 to 17, the length of the support beam 11 at a (i.e., the proximal end), the length of the support beam 11 at B (i.e., the middle end), and the length of the support beam 11 at C (i.e., the distal end) of the bare stent 1A gradually increases. The length of the support beam 11 is designed in a gradual change mode, so that when the support beam is expanded and formed into a conical support, the overall support performance and the flexibility are kept consistent, and the pulmonary artery covered stent 100 is ensured not to cause internal leakage in a long and bent blood vessel.

It should be noted that the proximal end and the distal end of the bare stent 1 are relative to the pulmonary artery stent graft 100 when being implanted for use, specifically, when the pulmonary artery stent graft 100 is implanted for use, the end of the bare stent 1 close to the operator in the axial direction of the pulmonary artery stent graft 100 is the proximal end, and correspondingly, the end of the stent far from the operator in the axial direction of the pulmonary artery stent graft 100 is the proximal end.

The diameter of the tapered stent formed after the pulmonary artery covered stent 100 is expanded is 15-17mm (for example, 15mm, 16mm, 17mm and the interval value between any two end values), and the tapered stent can be compressed in a 9F sheath, so that the tapered stent is more suitable for the characteristics of pulmonary artery vessels. In one embodiment, since the pulmonary artery stent graft 100 is shaped as a tapered stent after expansion, i.e., has a proximal diameter smaller than a distal diameter after expansion, optionally, the proximal diameter is 15mm and the distal diameter is 17mm after expansion.

In an alternative embodiment of the present invention, the bare stent 1 is made of a tube material, the wall thickness of the tube material is 0.1-0.2mm (e.g. 0.1mm, 0.15mm, 0.2mm and the interval value between any two end values), and the outer diameter is 2.5-3mm (e.g. 2.5mm, 2.8mm, 3mm and the interval value between any two end values).

In an optional embodiment of the invention, the bare stent 1 is made of one of stainless steel, cobalt-based alloy, platinum-iridium alloy, nickel-titanium alloy and magnesium-based alloy, and preferably nickel-titanium alloy.

In an alternative embodiment of the present invention, the outer membrane 21 is a two-layer PTFE (polytetrafluoroethylene) membrane, the inner membrane 22 is a layer of PTFE membrane, and the outer membrane 21 and the inner membrane 22 are respectively fixedly connected to the outer surface and the inner surface of the bare stent 1 by heat pressing. According to the invention, the outer membrane 21 and the inner membrane 22 both adopt PTFE membranes and have good flexibility and flexibility, so that the bare stent 1 coated with the membrane 2 has good flexibility and flexibility, and the problems of folds, cracks and the like of the membrane 2 are not easy to occur, thereby effectively ensuring the effectiveness of the membrane.

In an alternative embodiment of the present invention, the number of the connecting beams 12 should not exceed two, so as to ensure that the bare stent 1 after being covered with the film has good flexibility.

As shown in fig. 3 to 10, in an embodiment of the present invention, the supporting beam 11 has one supporting unit 11a, that is, the whole supporting unit 11a is a cylindrical structure with two open ends, two adjacent supporting beams 11 are connected by one connecting beam 12, and a plurality of connecting beams 12 are arranged in a staggered manner in the axial direction of the bare bracket 1. The structure setting like this can guarantee the radial force behind the naked support 1 tectorial membrane 2. It should be noted that the offset arrangement means that the connecting beams 12 are located at different cross sections in the axial direction of the bare stent 1.

As shown in fig. 11 to 17, in another embodiment of the present invention, the supporting beam 11 has two supporting units 11a, the two supporting units 11a together enclose to form a cylindrical structure, two connecting beams 12 are used to connect two adjacent supporting beams 11, the two connecting beams 12 are respectively connected to the two supporting units 11a, and the connecting beams 12 are arranged in a staggered manner in the axial direction of the bare bracket 1. The structure of the embodiment can also ensure the radial force after the bare stent 1 is covered with the membrane 2.

As shown in fig. 4 to 9 and 12 to 17, the support unit 11a includes a plurality of support tubes 111 and a plurality of arc support portions 112 alternately connected, the arc support portions 112 of two adjacent support beams 11 are disposed opposite to each other with a displacement, and both ends of the connecting beam 12 are connected to the two arc support portions 112 opposite to each other with a displacement, respectively. Such a structural arrangement may increase the flexibility of the bare stent 1, thereby increasing the flexibility of the pulmonary artery stent graft 100.

Alternatively, the number of the support tubes 111 may be between 10 and 15 (e.g., 10, 12, 13, 14, or 15), and the specific number may be selected according to the diameter of the pulmonary artery, with the greater the number of support tubes 111, the greater the radial force, and the better the expandability. Because the pulmonary artery covered stent 100 of the invention is formed into a tapered stent after being expanded, the number of the proximal supporting tubes 111 of the bare stent 1 is slightly less than that of the distal supporting tubes 111. In one embodiment of the present invention, 10 support tubes 111 are selected for the proximal end of the

bare stent

1, and 12 support tubes 111 are selected for the distal end of the bare stent 1.

It should be noted that the length of the connecting beam 12, the length of the supporting beam 11, the diameter ratio of the inner arc and the outer arc of the arc supporting portion 112, and the included angle between the supporting tubes 111 are all set according to the ratio before and after compression and expansion, so as to ensure the overall consistency of the effect of the expanded pulmonary artery covered stent 100. That is, the length of the connection beam 12, the length of the support beam 11, the ratio of the inner and outer arc diameters of the arc support portions 112, and the angle between the support tubes 111 are determined by the expanded diameter of the pulmonary artery stent graft 100.

In an alternative embodiment of the present invention, the length of the support tube 111 should be flexible, the length of each support beam 11 is determined according to the expanded diameter, and optionally, the length of the support tube 111 is flexible by 10-20% (e.g., 10%, 12%, 14%, 16%, 18%, 20% and the interval between any two endpoints).

In an alternative embodiment of the invention, the ratio of the inner arc diameter to the outer arc diameter of the arc supporting part 112 is 1:2, and the arc supporting parts 112 are arranged in a staggered and opposite manner, so that the structural arrangement can increase the flexibility of the pulmonary artery covered stent 100.

In an alternative embodiment of the present invention, the angle formed by two adjacent support tubes 111 is 50-70 ° (e.g., 50 °, 55 °, 60 °, 65 °, 70 °, or any interval therebetween) in the expanded state, preferably 60 °, such that the flexibility of the pulmonary artery stent graft 100 after expansion is ensured.

In alternative embodiments of the present invention, the connecting beam 12 has an S-shaped structure, an omega-shaped structure, or a corrugated structure.

In an alternative embodiment of the present invention, the length of the connecting beam 12 is 1/4-1/3 of the length of the supporting beam 11 in the axial direction of the bare stent 1.

Further, as shown in fig. 1, 3, 9 and 11, the image points 3 (i.e., mark points) are disposed at both ends of the bare stent 1, and the images of the pulmonary artery stent graft 100 in the blood vessel can be clearer due to the arrangement of the image points 3, so that the pulmonary artery stent graft 100 can be positioned more easily. Optionally, more than 3 image points 3 are respectively arranged at two end portions of the bare stent 1, so that non-overlapping images can be conveniently formed in the blood vessel, and the purposes of positioning the stent and observing the release condition of the stent can be achieved. Preferably, 4 image points 3 are respectively arranged at the two end parts of the bare stent 1.

Further, as shown in fig. 1, both ends of the bare stent 1 are flared to form bellmouths 4 after being expanded. Because the both ends of naked support 1 are not covered by tectorial membrane 2, can stereotype for the bell mouth 4 shape after its both ends expand, so structural arrangement can guarantee that pulmonary artery tectorial membrane support 100 implants in the use can not shift.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A pulmonary artery stent graft, comprising:

2. The pulmonary artery stent graft of claim 1, wherein the supporting beams have a supporting unit, two adjacent supporting beams are connected by one connecting beam, and the connecting beams are arranged in a staggered manner in the axial direction of the bare stent;

or, the supporting beam has two the supporting unit, adjacent two adopt two between the supporting beam the tie-beam is connected, two the tie-beam corresponds respectively to be connected in two the supporting unit, just in the axis direction of naked support, it is a plurality of the tie-beam is dislocation set.

3. The pulmonary artery covered stent as claimed in claim 2, wherein the supporting unit comprises a plurality of supporting tubes and a plurality of arc supporting parts which are alternately connected, the arc supporting parts of two adjacent supporting beams are arranged in a staggered and opposite manner, and two ends of the connecting beam are respectively connected to the two arc supporting parts in a staggered and opposite manner;

the number of the supporting tubes is 10-15, and the length expansion rate of the supporting tubes is 10-20%.

4. The pulmonary artery stent graft of claim 3, wherein the ratio of the inner to outer circular arc diameters of the circular arc struts is 1: 2;

and/or the included angle formed by two adjacent supporting pipes is 50-70 degrees in the expansion state.

5. The pulmonary artery stent graft of claim 1, wherein the connecting beam is in an S-shaped configuration, an omega-shaped configuration, or a corrugated configuration;

and/or the connecting beam is 1/4-1/3 of the supporting beam in length in the axial direction of the bare stent.

6. The pulmonary artery covered stent of claim 1, wherein the diameter of the formed tapered stent after the pulmonary artery covered stent is expanded is 15-17 mm.

7. The pulmonary artery stent graft of claim 1, wherein the bare stent is made of tubing, the tubing having a wall thickness of 0.1-0.2mm and an outer diameter of 2.5-3 mm;

and/or the bare stent is made of one of stainless steel, cobalt-based alloy, platinum-iridium alloy, nickel-titanium alloy and magnesium-based alloy.

8. The pulmonary artery stent graft of claim 1, wherein the outer membrane is a double layer of PTFE membrane and the inner membrane is a single layer of PTFE membrane, and wherein the outer and inner membranes are heat and pressure bonded to the outer and inner surfaces of the bare stent, respectively.

9. The pulmonary artery stent graft of any one of claims 1-8, wherein both ends of the bare stent are provided with image points.

10. The pulmonary artery stent graft of any one of claims 1-8, wherein both ends of the bare stent are flared after expansion.