WO2021065039A1

WO2021065039A1 - Artificial blood vessel and method for manufacturing artificial blood vessel

Info

Publication number: WO2021065039A1
Application number: PCT/JP2020/013122
Authority: WO
Inventors: 藤田　浩一; 遼平小林
Original assignee: テルモ株式会社
Priority date: 2019-09-30
Filing date: 2020-03-24
Publication date: 2021-04-08
Also published as: JPWO2021065039A1; JP7365424B2

Abstract

[Problem] To provide an artificial blood vessel in which the sealing ability of a sealing part impregnated into a sewn part that fixes a main vessel and a branch vessel is improved, and a method for manufacturing the artificial blood vessel. [Solution] An artificial blood vessel 100 comprising a main vessel 110 having an opening 112 on a side surface 111, a branch vessel 120A connected to the opening of the main vessel, a sewn part 130 at which the main vessel and the branch vessel are fixed by a suture 131, and a sealing part 140 which contains a thermoplastic elastomer and is impregnated into the sewn part, wherein the sewn part is squashed along the opening direction of the opening of the main vessel such that the suture extends more along the direction of extension of the main vessel than along the direction of extension of the branch vessel in a longitudinal cross section taken along the direction of extension of the main vessel and the branch vessel.

Description

Artificial blood vessels and methods for manufacturing artificial blood vessels

The present invention relates to an artificial blood vessel and a method for producing an artificial blood vessel.

An artificial blood vessel having a main tube and a branch tube connected to the main tube by a suture is known. In the artificial blood vessel described in Patent Document 1, in order to prevent blood or the like from leaking from the sewn portion where the main pipe and the branch pipe are sewn together, a seal portion made of a polymer material is formed in the sewn portion. There is.

Japanese Unexamined Patent Publication No. 7-429

The following problems may occur in the artificial blood vessel described in Patent Document 1. When forming the seal portion, the three-dimensional shape of the suture thread forming the sewn portion makes it easy for air bubbles to stay in the seal portion. If air bubbles stay in the seal part, especially in the part where the suture and the branch pipe are adjacent to each other (around the part where the branch pipe rises from the main pipe), the air bubbles are destroyed when an excessive load is applied to the sewn part. Blood may leak to the outside of the seal. In addition, the liquid (for example, water) used in the leak test performed after the production of the artificial blood vessel may stay in the bubbles and become a hotbed of bacteria.

The present invention has been made in view of the above circumstances, and provides an artificial blood vessel having improved sealing property of a seal portion impregnated in a sewn portion for fixing a main pipe and a branch pipe, and a method for manufacturing an artificial blood vessel. The purpose is to provide.

In the artificial blood vessel according to one aspect of the present invention, the main pipe having an opening on the side surface, the branch pipe connected to the opening of the main pipe, and the main pipe and the branch pipe are fixed by a suture. It has a sewn portion, a sealed portion containing a thermoplastic elastomer and impregnated in the sewn portion, and the sewn portion has a vertical cross section along the extending direction of the main pipe and the branch pipe. , The suture is crushed along the opening direction of the opening of the main pipe so that the suture extends longer along the extending direction of the main pipe than the extending direction of the branch pipe.

In the method for producing an artificial blood vessel according to another aspect of the present invention, a main tube having an opening on a side surface, a branch tube connected to the opening of the main tube, and the main tube and the branch tube are sutured. A method for manufacturing an artificial blood vessel having a sewn portion fixed by a thread, a seal portion containing a thermoplastic elastomer and impregnated in the sewn portion, in the extending direction of the main pipe and the branch pipe. The sewn portion is along the opening direction of the opening of the main pipe so that the suture extends longer along the extending direction of the main pipe than the extending direction of the branch pipe. Including crushing.

According to the present invention, it is possible to improve the sealing property of the sealing portion impregnated in the sewn portion that fixes the main pipe and the branch pipe.

It is a figure which shows the artificial blood vessel which concerns on embodiment. It is a figure which shows the part of the artificial blood vessel which concerns on embodiment in an enlarged manner. It is sectional drawing which shows the part of the artificial blood vessel which concerns on embodiment in an enlarged manner, and is the sectional view which follows the arrow 3A-3A shown in FIG. It is sectional drawing which shows the part of FIG. 3 enlarged. It is a flowchart which shows each process of the manufacturing method of the artificial blood vessel which concerns on embodiment. It is sectional drawing for demonstrating the step (S10) of forming a sewn portion. It is a perspective view for demonstrating the step (S10) of forming a sewn portion. It is sectional drawing for demonstrating the step (S20) of crushing a sewn portion. It is a perspective view for demonstrating the step (S20) of crushing a sewn portion. It is sectional drawing for demonstrating the step (S30) of forming a seal part. It is a perspective view for demonstrating the step (S30) of forming a seal part. It is a photograph which shows a part of the artificial blood vessel which concerns on Example. It is a photograph which shows a part of the artificial blood vessel which concerns on a comparative example.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. The present invention is not limited to the following embodiments. In addition, each drawing is exaggerated for convenience of explanation, and the dimensional ratio of each component in each drawing may differ from the actual one. Further, when the embodiment of the present invention is described with reference to the drawings, the same elements are designated by the same reference numerals in the description of the drawings, and duplicate description will be omitted.

1 to 4 are diagrams showing the artificial blood vessel 100 according to the embodiment. FIG. 5 is a diagram showing a flowchart of a method for manufacturing the artificial blood vessel 100 according to the embodiment. 6 to 11 are diagrams showing a method for manufacturing an artificial blood vessel according to an embodiment. FIG. 12 shows a photograph of a part of the cross section of the artificial blood vessel according to the example, and FIG. 13 shows a photograph of a part of the cross section of the artificial blood vessel according to the comparative example.

Each drawing and each photograph used in the description of the embodiment outlines the configuration of each part of the artificial blood vessel. The scope of the invention of the artificial blood vessel is not limited by the contents shown in each drawing.

The artificial blood vessel 100 according to the embodiment is outlined with reference to FIGS. 1, 3 and 4. In the artificial blood vessel 100, the main pipe 110 having an opening 112 on the side surface 111, the branch pipe 120 connected to the opening 112 of the main pipe 110, and the main pipe 110 and the branch pipe 120 are fixed by sutures 131. It has a sewn portion 130 and a seal portion 140 containing a thermoplastic elastomer and impregnating the sewn portion 130. In the sewn portion 130, the suture thread 131 is divided in a vertical cross section (cross section shown in FIGS. 3 and 4; hereinafter, also simply referred to as “longitudinal cross section”) along the extending direction of the main pipe 110 and the branch pipe 120. It is crushed along the opening direction of the opening 112 of the main pipe 110 so as to extend longer along the extending direction of the main pipe 110 than the extending direction of the branch pipe 120.

The extending direction of the main 110 is indicated by arrows X1-X2 in each figure. The extending direction of the branch pipe 120 is indicated by arrows Z1-Z2 in each figure. The opening direction of the opening 112 of the main pipe 110 is substantially the same as the extending direction of the main pipe 110.

<Main>
As shown in FIGS. 1 and 3, the main 110 is a tubular member having a lumen 114 extending in the extending direction of the main 110.

Openings

116 and 117 are formed at both ends of the main pipe 110 in the extending direction. The main pipe 110 has an uneven crimp 113 formed on the surface of the main pipe 110 (the outer surface of the side surface 111). The crimp 113 has a wavy cross-sectional shape in which irregularities are repeated along the extending direction of the main pipe 110.

As shown in FIGS. 3 and 4, the main 110 is composed of, for example, a multi-layered tubular member composed of a first layer (inner layer) 115a, a second layer (middle layer) 115b, and a third layer (outer layer) 115c. can do.

The first layer 115a can be made of, for example, a knitted tubular body. The first layer 115a can be made of, for example, polyester.

The second layer 115b can be composed of, for example, a non-porous tubular body. The second layer 115b can be made of, for example, a styrene-based elastomer.

The third layer 115c can be made of, for example, a woven tubular body. The third layer 115c can be made of, for example, polyester.

The material of each

layer

115a, 115b, 115c is not particularly limited. There are no particular restrictions on the number of layers constituting the main 110, the thickness of each layer, the structure, and the like.

As shown in FIGS. 1, 3 and 4, a branch pipe 120 is connected to the opening 112 of the main pipe 110. The artificial blood vessel 100 has one main pipe 110 and four

branch pipes

120A, 120B, 120C, and 120D connected to the main pipe 110. Four openings 112 are formed on the side surface 111 of the main pipe 110. The openings other than the opening 112 to which the branch pipe 120A is connected are not shown.

In the present embodiment, the

branch pipes

120A, 120B, 120C, and 120D have substantially the same configuration. Therefore, the details of the

branch pipes

120B, 120C, and 120D other than the branch pipe 120A will not be described. In the description of the present specification, when each

branch pipe

120A, 120B, 120C, 120D is generically referred to as a branch pipe 120.

The number of branch pipes 120 connected to the main pipe 110 is not particularly limited. The number and position of the openings 112 formed in the main pipe 110 can be appropriately changed according to the number and position of the branch pipes 120 connected to the main pipe 110.

<Sewing section>
In the vertical cross section shown in FIGS. 3 and 4, the suture 131 has a extending direction of the main pipe 110 (FIG. 3 and 4) rather than a extending direction of the branch pipe 120 (vertical direction of FIGS. 3 and 4). It extends long along the left-right direction). The suture thread 131 has an elliptical shape in which the minor axis is arranged along the extending direction of the branch pipe 120A and the long axis is arranged along the extending direction of the main pipe 110 in the vertical cross section. The minor axis of the suture 131 does not have to be parallel to the central axis c2 of the branch tube 120A. The long axis of the suture 131 does not have to be parallel to the central axis c1 of the main 110. In FIG. 4, the suture thread 131 is schematically shown by a broken line in order to illustrate the cross section of the seal portion 140.

The cross-sectional shape of the suture thread 131 shown in FIGS. 3 and 4 is only an example. The cross-sectional shape of the suture thread 131 is not particularly limited as long as it extends longer along the extending direction of the main pipe 110 than the extending direction of the branch pipe 120A.

The cross-sectional shape of the suture thread 131 before the sewn portion 130 is crushed is, for example, circular (see FIG. 6). However, the cross-sectional shape of the suture thread 131 before the sewn portion 130 is crushed is not particularly limited.

As shown in FIGS. 3 and 11, in the suture thread 131, the main pipe 110 and the branch pipe 120A are sewn together at a plurality of places so as to surround the circumference of the opening 112 of the main pipe 110. There are no particular restrictions on the number of stitches of the suture thread 131, the specific sewing method, or the like. The material of the suture thread 131 is also not particularly limited.

As shown in FIGS. 3 and 4, the maximum protruding position P1 of the sewn portion 130 is located closer to the central axis c1 of the main pipe 110 than the maximum protruding position P2 of the crimp 113 of the main pipe 110 in the vertical cross section. That is, the sewn portion 130 does not protrude from the crimp 113 of the main pipe 110 in the direction away from the central axis c1 of the main pipe 110 (outward in the radial direction). Therefore, the sewn portion 130 does not have a three-dimensional shape that excessively protrudes toward the outer surface side of the main pipe 110. Therefore, the artificial blood vessel 100 can suppress the mixing of air bubbles in the seal portion 140 applied to the sewn portion 130, particularly in the portion where the suture and the branch pipe are adjacent to each other, and improve the sealability of the seal portion 140. Can be planned. The specific positions (distance from the central axis c1 of the main pipe 110) of the maximum protruding position P1 of the sewn portion 130 and the maximum protruding position P2 of the crimp 113 are not particularly limited.

<Seal part>
As shown in FIG. 11, the seal portion 140 is impregnated outside the main pipe 110 and the branch pipe 120A between two adjacent stitches of the suture thread 131 (between the stitches of the suture thread 131). There is. Therefore, the sealing portion 140 can improve the sealing property between the adjacent sutures 131 outside the main pipe 110 and the branch pipe 120A.

As shown in FIG. 11, the seal portion 140 is impregnated between the suture thread 131 and the main pipe 110 and the branch pipe 120A outside the main pipe 110 and the branch pipe 120A. Therefore, the sealing portion 140 can improve the sealing property between the main pipe 110 and the branch pipe 120A outside the main pipe 110 and the branch pipe 120A.

The range in which the seal portion 140 is formed in the artificial blood vessel 100 is not particularly limited as long as at least a part of the seal portion 140 is impregnated in the sewn portion 130. That is, there is no particular limitation on the range in which the seal portion 140 is formed along the extending direction of the main pipe 110 and the range in which the seal portion 140 is formed along the extending direction of the branch pipe 120A.

The sealing portion 140 can be formed of a sealing material 140a in which a thermoplastic elastomer is dissolved in a predetermined solvent (see FIG. 11). The specific material of the thermoplastic elastomer and the specific material of the solvent are not particularly limited.

<Branch pipe>
As shown in FIGS. 1, 2 and 3, the branch pipe 120A is a tubular member having a lumen 124 extending in the extending direction of the branch pipe 120A. Openings 126 and 127 are formed at both ends of the branch pipe 120A in the extending direction. In the branch pipe 120A, one end 128 on the side where the opening 127 is formed is connected to the main pipe 110 (see FIGS. 3 and 4). The branch pipe 120A has an uneven crimp 123 formed on the surface of the branch pipe 120A. The crimp 123 has a wavy cross-sectional shape in which irregularities are repeated along the extending direction of the branch pipe 120A. The branch pipe 120A has an inner diameter and an outer diameter smaller than that of the main pipe 110.

The branch pipe 120A can be composed of, for example, a tubular member having a multi-layer structure including a first layer (inner layer) 125a, a second layer (middle layer) 125b, and a third layer (outer layer) 125c. Each of the

layers

125a, 125b, 125c of the branch pipe 120A can be composed of, for example, the same material and the same structure as each of the

layers

115a, 115b, 115c of the main pipe 110.

As shown in FIGS. 3 and 4, one end 128 of the branch pipe 120A is connected to the peripheral portion 112a of the opening 112 of the main pipe 110 by a suture thread 131. A boundary portion connecting the main pipe 110 and the branch pipe 120A is arranged in the sewing portion 130.

<Manufacturing method of artificial blood vessels>
Next, a method for manufacturing the artificial blood vessel 100 according to the present embodiment will be described with reference to FIGS. 5 to 11.

As shown in FIG. 5, the artificial blood vessel manufacturing method includes a step of forming a sewn portion (S10), a step of crushing the sewn portion (S20), and a step of applying a sealing material to the sewn portion (S30). Has.

As shown in FIGS. 6 and 7, the worker manufacturing the artificial blood vessel 100 sutures the branch pipe 120A to the opening 112 of the main pipe 110 using the suture thread 131. The operator fixes the main pipe 110 and the branch pipe 120A by the sewing portion 130.

The operator crushes the sewing portion 130 as shown in FIGS. 8 and 9. For example, in a state where the main pipe 110 and the branch pipe 120A are set on a predetermined jig, the operator presses the mold on the entire circumference of the sewing portion 130 to push the sewing portion 130 to the central axis c1 side of the main pipe 110. Can be crushed. The method of crushing the sewn portion 130 is not limited to the above method.

The operator applies the sealing material 140a to the sewn portion 130 as shown in FIGS. 10 and 11. The sewn portion 130 is crushed before applying the sealing material 140a. Therefore, the sewn portion 130 is reduced from protruding toward the outer surface side of the main pipe 110 and protruding toward the outer surface side of the branch pipe 120A. Therefore, the outer surface of the main pipe 110 and the outer surface of the branch pipe 120A have a flatter shape. The operator can prevent gas such as air from being taken into the inside of the sealing material 140a applied to the sewing portion 130. The operator can form the seal portion 140 by applying the seal material 140a and then curing the seal material 140a.

FIG. 12 shows an enlarged photograph of a part of the artificial blood vessel 100 according to the example manufactured by the manufacturing method according to the present embodiment. FIG. 13 shows an enlarged photograph of a part of the artificial blood vessel manufactured by the manufacturing method according to the comparative example. In the manufacturing method according to the comparative example, the step of crushing the sewn portion 130 is not carried out.

As shown in FIG. 12, when the manufacturing method according to the present embodiment is adopted, the suture thread 131 has a cross-sectional shape crushed along the opening 112 of the main pipe 110. Therefore, it is possible to prevent the sewn portion 130 from excessively protruding toward the outer surface side of the main pipe 110 and the outer surface side of the branch pipe 120A. As a result, it is possible to prevent air bubbles from being mixed into the seal portion 140 applied to the sewn portion 130, and it is possible to improve the sealability of the seal portion 140. In particular, since there are no air bubbles in the portion of the seal portion 140 where the suture thread 131 and the branch pipe 120A are adjacent to each other, the sealability of the seal portion 140 is further improved. Even if some air bubbles are present in the portion of the seal portion 140 where the suture thread 131 and the main pipe 110 are adjacent to each other, it is unlikely that the air bubbles will be destroyed. Is unlikely to leak out. As shown in FIG. 13, when the manufacturing method according to the comparative example is adopted, the suture thread 131 is not crushed along the opening 112 of the main pipe 110. Therefore, the sewn portion 130 exhibits a three-dimensional shape protruding from the outer surface side of the main pipe 110 and the outer surface side of the branch pipe 120A. Therefore, when the manufacturing method according to the comparative example is adopted, when the sealing material 140a is applied to the sewn portion 130, gas such as air is easily taken into the inside of the sealing material 140a. Therefore, air bubbles stay in the portion of the seal portion 140 where the suture thread 131 and the branch pipe 120A are adjacent to each other. Then, such bubbles are destroyed when the artificial blood vessel 100 is pulled, which causes blood to leak to the outside of the seal portion 140.

As described above, the artificial blood vessel 100 according to the present embodiment includes a main pipe 110 having an opening 112 on the side surface 111, a branch pipe 120 connected to the opening 112 of the main pipe 110, and a main pipe 110 and a branch. The tube 120 has a sewn portion 130 fixed by a suture thread 131, and a seal portion 140 containing a thermoplastic elastomer and impregnated with the sewn portion 130. In the vertical cross section along the extending direction of the main pipe 110 and the branch pipe 120, the sewing portion 130 extends the suture 131 longer along the extending direction of the main pipe 110 than the extending direction of the branch pipe 120. Is crushed along the opening direction of the opening 112 of the main pipe 110.

The method for manufacturing the artificial blood vessel 100 according to the present embodiment includes a main pipe 110 having an opening 112 on the side surface 111, a branch pipe 120 connected to the opening 112 of the main pipe 110, and the main pipe 110 and the branch pipe 120. Is a method for manufacturing an artificial blood vessel having a sewn portion 130 fixed by a suture 131 and a seal portion 140 containing a thermoplastic elastomer and impregnated with the sewn portion 130. The method is such that the suture 131 extends longer along the extending direction of the main pipe 110 than the extending direction of the branch pipe 120 in the longitudinal section along the extending direction of the main pipe 110 and the branch pipe 120. , Including crushing the sewn portion 130 along the opening direction of the opening 112 of the main pipe 110.

According to the present embodiment, the sewn portion 130 is suppressed from protruding toward the outer surface side of the main pipe 110 and protruding toward the outer surface side of the branch pipe 120A by the suture thread 131. Therefore, it is possible to prevent gas such as air from being taken into the inside of the seal portion 140 impregnated in the sewn portion 130. The artificial blood vessel 100 has an improved sealing property of the sealing portion 140. Further, since the artificial blood vessel 100 can suppress the accumulation of air bubbles in the seal portion 140, it is possible to suppress the occurrence of bacterial contamination due to the accumulation of air bubbles.

The present invention is not limited to the above-described embodiment, and various modifications can be made within the scope of the claims.

The artificial blood vessel described in the embodiment exemplifies one specific embodiment, and the arrangement and structure of each member can be changed as appropriate.

Each procedure explained in the method of manufacturing an artificial blood vessel is an example. Other steps may be added to the method for producing the artificial blood vessel, and some steps may be omitted or replaced. For example, the order of the step of crushing the sewn portion and the step of applying the sealing material to the sewn portion may be changed. When the processes are replaced in this way, even if air or other air bubbles are taken into the sealing material when the sealing material is applied, the sealing is performed by performing the step of crushing the sewn portion after applying the sealing material. Air bubbles can be removed from the material. Therefore, it is possible to manufacture an artificial blood vessel in which the sealing property of the sealing portion impregnated in the sewn portion is improved.

This application is based on Japanese Patent Application No. 2019-178731 filed on September 30, 2019, the disclosure of which is cited as a whole by reference.

100 Artificial blood vessel 110 Main pipe 111 Side surface 112 Opening 112a Peripheral part of opening 113 Main main crimp 114 Main

main lumen

120, 120A, 120B, 120C, 120D Branch pipe 123 Branch pipe crimp 124 Inside the branch pipe Cavity 130 Sewing part 131 Suture 140 Sealing part 140a Sealing material P1 Maximum protruding position of sewing part P2 Maximum protruding position of crimp c1 Central axis of main pipe c2 Central axis of main pipe

Claims

The main with an opening on the side and
A branch pipe connected to the opening of the main pipe and
A sewn portion in which the main pipe and the branch pipe are fixed by sutures,
It contains a thermoplastic elastomer and has a seal portion impregnated in the sewn portion.
The sewn portion has a longitudinal cross section along the extending direction of the main pipe and the branch pipe so that the suture extends longer along the extending direction of the main pipe than the extending direction of the branch pipe. An artificial blood vessel that is crushed along the opening direction of the opening of the main tube.
The artificial blood vessel according to claim 1, wherein the seal portion is impregnated between two adjacent stitches of the suture outside the main pipe and the branch pipe.
The artificial blood vessel according to claim 1 or 2, wherein the seal portion is impregnated between the suture and the main pipe and the branch pipe outside the main pipe and the branch pipe. ..
The main has an uneven crimp formed on the surface of the main.
The maximum protrusion position of the sewn portion is located on the central axis side of the main pipe with respect to the maximum protrusion position of the crimp of the main pipe in the vertical cross section, according to any one of claims 1 to 3. Artificial blood vessel.
A main body having an opening on a side surface, a branch pipe connected to the opening of the main pipe, a sewn portion in which the main pipe and the branch pipe are fixed by sutures, and a thermoplastic elastomer are included. , A method of manufacturing an artificial blood vessel having a seal portion impregnated in the sewn portion.
In a longitudinal section along the extending direction of the main pipe and the branch pipe, the suture extends longer along the extending direction of the main pipe than the extending direction of the branch pipe. A method for manufacturing an artificial blood vessel, which comprises crushing the sewn portion along the opening direction of the opening.
The method for producing an artificial blood vessel according to claim 5, wherein the sealing portion is formed by applying a sealing material in which the thermoplastic elastomer is dissolved in a solvent to the sewing portion.
The method for manufacturing an artificial blood vessel according to claim 6, wherein the sealing material is applied to the sewn portion after crushing the sewn portion along the opening direction of the opening of the main pipe.