CN114432005A

CN114432005A - Artificial heart valve braided stent

Info

Publication number: CN114432005A
Application number: CN202011225656.5A
Authority: CN
Inventors: 瑞恩·亨利福特
Original assignee: Shanqian Zhuhai Biomaterial Technology Co ltd
Current assignee: Shanqian Zhuhai Biomaterial Technology Co ltd
Priority date: 2020-11-05
Filing date: 2020-11-05
Publication date: 2022-05-06

Abstract

The invention discloses a braided stent for a prosthetic heart valve. The artificial heart valve braided stent comprises an annular structure (1) obtained by adopting a triaxial braiding method; the weft (11) in the annular structure (1) is made of metal, and the warp (12) adopted in the triaxial weaving method is made of elastic material; the ring-shaped structure (1) comprises a first state in which the warp threads (12) are in a natural condition, and a second state in which the warp threads (12) are in a stretched condition; the circumference of the ring-shaped structure (1) in the first state is larger than the circumference of the ring-shaped structure (1) in the second state. The artificial heart valve braided stent can realize circumferential expansion by adopting different expansion forces, so that the preparation process is effectively simplified, and the production cost is reduced.

Description

Artificial heart valve braided stent

Technical Field

The invention relates to the field of medical appliances, in particular to a braided stent for a prosthetic heart valve.

Background

Most transcatheter delivered prosthetic heart valve stents consist of only metal elements that are laser cut from thin-walled tubing or made of thin metal wires, and the desired shape is constructed using the metal elements. The artificial heart valve component is obtained by fixing the artificial heart valve on the artificial heart valve support and assembling the artificial heart valve support, and the artificial heart valve component can be conveyed through a small catheter with the inner diameter as small as 14Fr in the mode of assembling the support and the artificial heart valve, so that the Transcatheter Aortic Valve Replacement (TAVR) can be effectively implemented.

The valve stents made of metal wires disclosed in the prior art are generally made of memory alloys, and the manufacturing method thereof is complicated and requires a heat treatment for a progressive shape memory. For example, chinese document CN101172058 discloses a stent valve with a stent and a biological valve woven into a whole, and the stent disclosed in the document is formed by: the first time of weaving the stent, the heat treatment of shape memory is carried out on the woven stent, the stent after the heat treatment is disassembled along the opposite direction of the first time of weaving, and the second time of weaving is carried out for restoring the disassembled stent weaving wire into the stent. Therefore, when the stent is released at the far end of the catheter, the expansion of the circumferential perimeter of the stent is realized by the memory of the metal wire material.

In conclusion, the valve stent made of the metal wire disclosed in the prior art has the problem of complicated preparation method.

Disclosure of Invention

Therefore, the technical problem to be solved by the invention is to overcome the defect that the preparation method is complex when the valve stent is prepared by adopting the metal wire of the memory alloy in the prior art, so that the artificial heart valve braided stent can realize circumferential expansion by adopting different expansion forces, further effectively simplifies the preparation process and reduces the production cost.

A woven prosthetic heart valve stent comprising:

comprises a ring structure obtained by adopting a triaxial weaving method;

the weft adopted in the triaxial weaving method is made of metal, and the warp adopted in the triaxial weaving method is made of elastic material;

the annular structure comprises a first state that the warp threads are in a natural condition and a second state that the warp threads are in a stretching state; the circumference of the ring-shaped structure in the first state is larger than the circumference of the ring-shaped structure in the second state.

The triaxial weaving method is a method for forming a plane or tubular fabric by mutually winding and weaving two groups of weft yarns at a certain angle of positive and negative and three groups of warp yarns at 0 degree. Since the triaxial weaving method is the prior art, the specific weaving method is not described herein again.

The axial direction of the annular structure is the warp direction.

The annular structure is an integrally formed structure.

The ring-shaped structure includes: the sheet structure is obtained by adopting a triaxial weaving method, and opposite ends of the sheet structure are mutually connected to form a ring-shaped connecting piece.

The elastic material is a biocompatible material.

The elastic material is TPU.

The number of warp threads which are axially parallel to the annular structure is not less than 3.

The specification of the weft is 0.001-0.040D; the specification of the warp is 50-600D.

The technical scheme of the invention has the following advantages:

1. the invention provides a woven stent for a prosthetic heart valve, which is woven by a triaxial weaving method and is annular in shape, wherein weft is made of metal material, warp is made of elastic material, and the annular structure comprises a first state that the warp is under natural conditions and a second state that the warp is under stretching; the circumference of the ring-shaped structure in the first state is larger than the circumference of the ring-shaped structure in the second state. That is, the present invention weaves the warp yarns having elasticity in the weft yarns overlapping each other to form a triaxial weave structure well known in the industry. According to the invention, through the optimization of materials and structures, the warp can effectively assist the expansion of the stent; specifically, when the warp is in an axially stretched state, the circumferential diameter is effectively compressed, the axial length is effectively extended, and the stent can be effectively placed in a transmission tube; therefore, the present invention achieves circumferential stent expansion in a different expansion manner than that achieved in the prior art using the metal's own memory of expansion force, which effectively solves the problem of complexity of the existing stent manufacturing manner, effectively simplifies the manufacturing steps, and at the same time, greatly reduces the overall production cost relative to the prior art by eliminating the use of expensive shape memory metals and the associated manufacturing, assembly and heat treatment costs.

2. The invention further optimizes the selection of the material of the warp, the elastic material is preferably an elastic material with biocompatibility, the elastic material is further preferably TPU, and the optimization of the material can effectively reduce the tissue reaction and improve the safety.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.

FIG. 1 is a schematic structural diagram of a braided stent for a prosthetic heart valve according to the present invention;

FIG. 2 is a partially enlarged schematic structural view of the woven stent for a prosthetic heart valve in example 1;

description of reference numerals:

1-a ring-shaped structure;

11-weft and 12-warp.

Detailed Description

The technical solutions of the present invention will be described clearly and completely with reference to the accompanying drawings, and it should be understood that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; may be directly connected or indirectly connected through an intermediate. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

Furthermore, the technical features involved in the different embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

Example 1

A woven stent for a prosthetic heart valve, as shown in fig. 1 and 2, comprises an annular structure 1 obtained by means of a triaxial weaving method. The weft 11 adopted in the triaxial weaving method is made of metal, and the warp 12 adopted in the triaxial weaving method is made of elastic material; the ring-shaped structure 1 comprises a first state in which the warp yarns 12 are in a natural condition, and a second state in which the warp yarns 12 are in a stretched condition; the circumference of the ring-shaped structure 1 in the first state is larger than the circumference of the ring-shaped structure 1 in the second state. The triaxial weaving method in this embodiment is a weaving method in which two positive and negative wefts 11 at a certain angle and one 0-degree warp are interlaced, and the method is the prior art and is not described herein again. The weaving angle of the weft 11 may be different angles such as plus or minus 30 degrees, plus or minus 45 degrees, and the angle may be appropriately adjusted according to the circumstances.

Because the woof is the metal material, and the warp is the elasticity material, and the girth of annular structure 1 under the first state is greater than the girth of annular structure 1 under the second state. Therefore, through the joint optimization of the materials and the structure, the warp can effectively assist the expansion of the stent; specifically, when the warp is in an axially stretched state, the circumferential diameter is effectively compressed, the axial length is effectively extended, and the stent can be effectively placed in a transmission tube; therefore, the present invention achieves circumferential stent expansion using a different expansion means than the prior art using the metal's own memory of expansion force, which effectively solves the problem of the complexity of the prior stent manufacturing means, effectively simplifies the manufacturing steps, and at the same time, greatly reduces the overall production costs over the prior art by eliminating the use of expensive shape memory metals and the associated manufacturing, assembly and heat treatment costs.

The axial direction of the ring structure 1 may be parallel to the warp threads or may form an angle with the warp threads. Preferably, the axial direction of the ring-shaped structure 1 is the warp direction, i.e. the direction in which the warp is located, in which case it can be seen that: the annular structure 1 in this embodiment is a triaxial weave structure well known in the industry, which is formed by weaving warp yarns having elasticity in weft yarns overlapping with each other in the axial direction of the annular structure 1.

The artificial heart valve braided stent provided by the embodiment can be directly braided into an integrally formed annular structure 1 by adopting a triaxial braiding method; or a sheet structure can be obtained by adopting a triaxial weaving method, and then opposite ends of the sheet structure are connected with each other through a connecting piece to form a ring shape, so that a ring structure 1 is formed, as shown in fig. 1. In this embodiment, the annular structure 1 is integrally knitted by using a triaxial knitting method, and specifically, a pentagonal pillar (Maypole) type knitting machine may be used, for example: series K80 from Steeger, usa, which can be used for this structure to achieve direct braiding, the partial shape after braiding is shown in fig. 2.

In this embodiment, the elastic material is preferably an elastic material having biocompatibility, and is more preferably TPU. In this case, the warp 12 is a thermoplastic polyurethane monofilament formed by extrusion molding, and the weft 11 is a metal wire. The specification of the thermoplastic polyurethane single fiber is selected to be 50-600D, and the specification of the metal wire is selected to be 0.001-0.040D; the specification of the thermoplastic polyurethane single fiber is 150D in the embodiment, and the specification of the metal wire is 0.020D, in this case, the number of the warp threads 12 parallel to the axis of the annular structure 1 is not less than 3, and the number of the warp threads 12 is preferably set to 8 under the above specification conditions in the embodiment.

Example 2

A braided stent structure for artificial heart valves, which is different from the braided stent structure of embodiment 1 in that the structure of the annular structure 1 is different, and the braided stent structure is specifically arranged as follows:

in the embodiment, the sheet structures are connected by the connecting pieces to form the annular structure 1, as shown in fig. 1. At this time, the connecting piece can adopt a sewing mode, an adhesion mode, a welding mode or a mechanical connection mode; in this embodiment, when the suture mode is adopted, thermoplastic polyurethane single fibers may be adopted as the suture line; in this embodiment, it is only necessary to ensure that the annular central axis formed by connecting the two opposite ends of the sheet-like structure is consistent with the weaving direction of the warp 12 on the sheet-like structure.

The artificial heart valve woven stent in the embodiment can be effectively suitable for installation of the leaflet assembly.

It should be understood that the above examples are only for clarity of illustration and are not intended to limit the embodiments. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. And obvious variations or modifications therefrom are within the scope of the invention.

Claims

1. A woven stent for prosthetic heart valves, characterized in that it comprises an annular structure (1) obtained by means of a triaxial weaving process;

the weft (11) in the annular structure (1) is made of metal, and the warp (12) adopted in the triaxial weaving method is made of elastic material;

the ring-shaped structure (1) comprises a first state in which the warp threads (12) are in a natural condition, and a second state in which the warp threads (12) are in a stretched condition; the circumference of the ring-shaped structure (1) in the first state is larger than the circumference of the ring-shaped structure (1) in the second state.

2. The woven stent for a prosthetic heart valve according to claim 1, characterized in that the axial direction of the annular structure (1) is the warp direction.

3. The woven stent for a prosthetic heart valve according to claim 1 or 2, characterized in that the annular structure (1) is an integrally formed structure.

4. The woven stent for a prosthetic heart valve according to claim 1 or 2, characterized in that said annular structure (1) comprises: the sheet structure is obtained by adopting a triaxial weaving method, and opposite ends of the sheet structure are mutually connected to form a ring-shaped connecting piece.

5. The woven stent for a prosthetic heart valve according to any one of claims 1-4, wherein the elastic material is a biocompatible material.

6. The woven stent for a prosthetic heart valve according to any one of claims 1-5, wherein the elastic material is TPU.

7. The woven stent for a prosthetic heart valve according to any one of claims 1 to 6, wherein the number of warp threads (12) in the annular structure (1) parallel to the axial direction thereof is not less than 3.

8. The woven holder of prosthetic heart valves according to any one of claims 1-7, characterized in that the weft (11) has a gauge of 0.001-0.040D; the specification of the warp (12) is 50-600D.