WO2024181480A1

WO2024181480A1 - Artificial blood vessel connection structure

Info

Publication number: WO2024181480A1
Application number: PCT/JP2024/007215
Authority: WO
Inventors: 伸作小嵐
Original assignee: 株式会社ハイレックスコーポレーション
Priority date: 2023-02-28
Filing date: 2024-02-28
Publication date: 2024-09-06
Also published as: JP2024122753A

Abstract

An artificial blood vessel connection structure according to the present invention is provided with: a connector (2) provided with a first cylindrical part (211) and a second cylindrical part (212); a locking member (3) provided with an engagement part (31); and a ferrule (4). In the artificial blood vessel connection structure, the second cylindrical part (212) has a recessed and projecting part (212a). The artificial blood vessel connection structure is further provided with an elastic member (5) that is disposed outside in the radial direction of the recessed and projecting part (212a) and inside in the radial direction of the ferrule (4). The ferrule (4) is provided with a leg part (41) that is displaceable inwardly in the radial direction. The locking member (3) is provided with a pressing part (33) that presses the leg part (41) inwardly in the radial direction to displace the same. The elastic member (5) is configured to be pressed toward the recessed and projecting part (212a) so as to be elastically deformed, when the leg part (41) is displaced inwardly in the radial direction by the pressing part (33). Due to this configuration, the artificial blood vessel connection structure having a simple structure and high blood leakage resistance can be provided.

Description

Artificial blood vessel connection structure

The present invention relates to an artificial blood vessel connection structure.

For example, a connection structure such as that in Patent Document 1 has been disclosed as a means for connecting an artificial blood vessel to a connection target such as an auxiliary artificial heart. This connection structure connects the artificial blood vessel to a connection target by attaching the connection structure to the end of the artificial blood vessel. The connection structure in Patent Document 1 is configured to radially clamp the end of the artificial blood vessel by screwing a nut onto the connector portion and moving the nut axially relative to the connector portion.

International Publication No. 2015/097906

In such a connection structure, for example, if the entire artificial blood vessel has a pleated structure with continuous unevenness along the axial direction, wrinkles may occur at the end of the artificial blood vessel having the pleated structure when the end of the artificial blood vessel is sandwiched in the radial direction. These wrinkles occur when the pleated structure deforms unevenly when sandwiched by the connecting structure, which may result in a gap between the connecting structure and the artificial blood vessel. In order to prevent the occurrence of wrinkles that increase the possibility of blood leakage, for example, it is possible to use an artificial blood vessel with a smooth surface that does not have a pleated structure at the end of the artificial blood vessel that is sandwiched in the radial direction. However, in that case, the manufacturing cost of the artificial blood vessel will increase, and in order to prevent the occurrence of gaps between the smooth surface and the connecting structure, it will be necessary to attach a separate member such as a ring member to the end of the artificial blood vessel and then attach it to the connecting structure, making the structure complicated.

The present invention aims to provide an artificial blood vessel connection structure that is simple in structure and highly resistant to blood leakage.

The artificial blood vessel connection structure of the present invention is an artificial blood vessel connection structure for connecting an artificial blood vessel to a connection object, the artificial blood vessel connection structure comprising a connector connected to the connection object, the connector comprising a first tubular portion having an engaged portion, and a second tubular portion arranged on one side of the first tubular portion in the axial direction and fitted inside the artificial blood vessel, an engagement portion that engages with the engaged portion of the first tubular portion, and a locking member tubular portion arranged radially outward of the second tubular portion, the locking member tubular portion being connected to the connector, and a locking member tubular portion being provided between the second tubular portion of the connector and the locking member tubular portion of the locking member in the radial direction of the locking member. The second cylindrical portion of the connector has an uneven portion on at least a part of the outer periphery of the second cylindrical portion, the artificial blood vessel connection structure further includes an annular elastic member arranged radially outside the uneven portion and radially inside the ferrule, the ferrule has flexible legs that can be displaced radially inward, the locking member has a pressing portion on the inner surface of the locking member cylindrical portion that presses the legs radially inward to displace them, and the elastic member is configured to be pressed toward the uneven portion by the inner surface of the ferrule and elastically deformed when the legs are displaced radially inward by the pressing portion.

The present invention provides an artificial blood vessel connection structure that is simple in structure and highly resistant to blood leakage.

1 is a schematic diagram showing a state in which an artificial blood vessel connection structure according to one embodiment of the present invention is connected to a connection target. FIG. 1 is an exploded perspective view of an artificial blood vessel connection structure according to one embodiment of the present invention. FIG. 2 is an exploded plan view of the artificial blood vessel connection structure of one embodiment of the present invention. FIG. 4 is a cross-sectional view taken along line IV-IV in FIG. FIG. 1 is a perspective view of an artificial blood vessel connection structure according to one embodiment of the present invention in which a locking member and a connector are connected. 1 is a plan view of an artificial blood vessel connection structure according to one embodiment of the present invention in which a locking member and a connector are connected. FIG. 7 is a cross-sectional view taken along line VII-VII of FIG. 6. 4 is a cross-sectional view of the connector and the artificial blood vessel cut in the axial direction, showing the state in which the artificial blood vessel is attached to the connector. FIG. 4 is a cross-sectional view taken along an axial direction of the connector, the ferrule, and the locking member, showing a state in which the ferrule is attached to the connector and before the locking member is connected. FIG. FIG. 10 is a partial enlarged view of an area A2 in FIG. 9 . 10 is a cross-sectional view of the connector, the ferrule, and the locking member cut in the axial direction, showing a state in which the locking member has moved axially from the state shown in FIG. 9 and the pressing portion of the locking member abuts against the pressed portion of the ferrule. FIG. 8 is a partial enlarged view of an area A1 in FIG. 7 . 11 is a schematic diagram showing an elastic member in a state where it is elastically deformed by radially inward displacement of the legs of the ferrule; FIG.

Below, an artificial blood vessel connection structure according to one embodiment of the present invention will be described with reference to the drawings. Note that the embodiment shown below is merely an example, and the artificial blood vessel connection structure of the present invention is not limited to the following embodiment.

In this specification, "perpendicular to A" and similar expressions do not only refer to a direction that is completely perpendicular to A, but also refer to a direction that is approximately perpendicular to A. Furthermore, in this specification, "parallel to B" and similar expressions do not only refer to a direction that is completely parallel to B, but also refer to a direction that is approximately parallel to B. Furthermore, in this specification, "C-shape" and similar expressions do not only refer to a perfect C-shape, but also refer to a shape that visually resembles a C-shape (approximately a C-shape).

As shown in FIG. 1, the artificial blood vessel connection structure 1 of this embodiment is used to connect an artificial blood vessel VE to a connection object C. By connecting the artificial blood vessel VE to the connection object C using the artificial blood vessel connection structure 1, blood can flow to or from the connection object C via the artificial blood vessel VE.

The connection object C is an object to which the artificial blood vessel VE is connected via the artificial blood vessel connection structure 1 (specifically, the connector 2 (see FIG. 2) described later). In this embodiment, the connection object C is an auxiliary artificial heart. However, the connection object is not particularly limited as long as it is an object to which the artificial blood vessel VE can be connected, and may be other organs, blood vessels, etc. to which the artificial blood vessel VE needs to be connected. In this embodiment, as shown in FIG. 1, one end of the artificial blood vessel VE is connected to the connection object C, which is an auxiliary artificial heart, via the artificial blood vessel connection structure 1, and the other end of the artificial blood vessel VE is sutured to the human body (a blood vessel such as the aorta or an organ such as the heart).

The connection object C has a connection part Ca to which the connector 2 of the artificial blood vessel connection structure 1 described later is connected. The connection part Ca is liquid-tightly connected to the connector 2 of the artificial blood vessel connection structure 1. In this embodiment, the connection part Ca is liquid-tightly connected by being screwed into the connector 2. However, the joining structure between the connection part Ca and the connector 2 is not particularly limited as long as the connection part Ca and the connector 2 can be connected liquid-tightly.

The artificial blood vessel VE is a medical tubular member that serves as a substitute for a biological blood vessel, for example to replace a diseased biological blood vessel and bypass the biological blood vessel. The artificial blood vessel VE is connected to a connection object C via a connector 2, a locking member 3, and a ferrule 4, which will be described later.

The artificial blood vessel VE may have a structure similar to that of a known artificial blood vessel. The structure and material of the artificial blood vessel VE are not particularly limited as long as it is a medical tubular member that substitutes for a biological blood vessel and can be connected to the connection target C. The artificial blood vessel VE may be, for example, a cloth artificial blood vessel in which fibers such as polyester are woven in a predetermined weaving structure. In this embodiment, the artificial blood vessel VE has a pleated structure in which peaks M and valleys V (see FIG. 8) are alternately formed over the entire length direction (axis X (see FIG. 2) direction) of the artificial blood vessel VE. In this embodiment, the artificial blood vessel VE also has peaks M and valleys V formed at the end where the second tubular portion 212 of the connector 2 described later is inserted (see FIG. 8). When peaks M and valleys V are alternately formed in the artificial blood vessel VE, the artificial blood vessel VE can be flexible and is less likely to kink when bent. In this embodiment, the artificial blood vessel VE is formed in a cylindrical shape in which the peaks M and valleys V are formed in a spiral shape. The peaks and valleys of the artificial blood vessel VE may be arranged in a ring shape around the axis X of the artificial blood vessel VE, rather than in a spiral shape.

The diameter and length of the artificial blood vessel VE can be changed depending on the part to be used, and are not particularly limited. For example, the artificial blood vessel VE may be a large-diameter artificial blood vessel with an inner diameter of 10 mm or more (for the thoracic and abdominal aorta), a medium-diameter artificial blood vessel with an inner diameter of 6 mm or more but less than 10 mm, such as 6 mm or 8 mm (for the arteries in the lower limbs, neck, and axillary regions), or a small-diameter artificial blood vessel with an inner diameter of less than 6 mm. The thickness of the artificial blood vessel VE can be changed appropriately depending on the inner diameter and length of the artificial blood vessel to be used, and is not particularly limited. For example, the thickness of the artificial blood vessel VE can be 0.1 to 2 mm.

As shown in Figure 2, the artificial blood vessel connection structure 1 of this embodiment includes a connector 2, a locking member 3, and a ferrule 4. The artificial blood vessel connection structure 1 further includes a ring-shaped elastic member 5. In this embodiment, the artificial blood vessel connection structure 1 further includes an artificial blood vessel VE (shown by a two-dot chain line in Figures 2 to 7, 9, and 11).

In this specification, when the term "axis X direction" is used with respect to each member of the artificial blood vessel connection structure 1, it refers to the direction along the central axis (axis X) of the part of the artificial blood vessel VE arranged outside the second cylindrical portion 212 described later in the artificial blood vessel connection structure 1 in a state in which the artificial blood vessel VE is connected. In this embodiment, the connector 2, the locking member 3, the ferrule 4, etc. are all approximately cylindrical, and the axis of the artificial blood vessel VE coincides with the axis of the connector 2, the locking member 3, and the ferrule 4. In addition, in this specification, "one side in the axis X direction" is the direction away from the connection object C when the artificial blood vessel connection structure 1 is connected to the connection object C (the right side in FIG. 3). In other words, "one side in the axis X direction" is the direction in which the artificial blood vessel VE connected to the connector 2 is detached from the connector 2. In addition, in this specification, "the other side in the axis X direction" is the direction approaching the connection object C when the artificial blood vessel connection structure 1 is connected to the connection object C (the left side in FIG. 3). In other words, "one side in the direction of axis X" is the direction in which the artificial blood vessel VE moves when it is fitted into the connector 2. In addition, in this specification, "radial direction" refers to the radial direction of the tubular members (in this embodiment, the artificial blood vessel VE, the first tubular portion 211 of the connector 2, the second tubular portion 212, the ferrule 4, the locking member 3, etc.). Note that the expression "radial direction" does not necessarily mean that the member using the expression "radial direction" has a cylindrical outer shape. In addition, the circumferential direction refers to the direction around the axis X on the outer surface or inner surface of each member of the artificial blood vessel connection structure 1.

The connector 2 is a part that is connected to the connection object C, and the artificial blood vessel connection structure 1 is connected to the connection object C by connecting the connector 2 to the connection object C (connected part Ca). The connector 2 is also configured so that the artificial blood vessel VE can be attached. The connector 2 is a tubular member that has an internal space that communicates with the space inside the artificial blood vessel VE when the artificial blood vessel VE is attached. The material that constitutes the connector 2 is not particularly limited, but it is generally made of a material (e.g., titanium, etc.) that is biocompatible and has a predetermined rigidity.

2 to 4, the connector 2 includes a first cylindrical portion 211 having an engaged portion 211a, and a second cylindrical portion 212 that is disposed on one side of the first cylindrical portion 211 in the axial direction X and is fitted inside the artificial blood vessel VE. In this embodiment, the connector 2 also includes a connecting portion 22 that is connected to the connection object C. In this embodiment, the connecting portion 22 has a female threaded portion on the inner surface (see FIG. 4) and is connected to the connection object C by screwing with a male threaded portion (not shown) provided on the connected portion Ca of the connection object C. In this embodiment, the connector 2 includes a connector main body 21 having a first cylindrical portion 211 and a second cylindrical portion 212, and a connecting portion 22 that is configured as a separate body from the connector main body 21, as shown in FIG. 2 to 4. However, the connecting portion 22 may be provided integrally with the connector main body 21. The connecting portion 22 is configured as an annular member that engages with the other end of the connector main body 21 in the axial direction X. In this embodiment, as shown in Figures 2 to 4, in addition to the first cylindrical portion 211 and the second cylindrical portion 212, the connector main body 21 has a third cylindrical portion 213 on the other side in the axial X direction relative to the first cylindrical portion 211, and the connecting portion 22 is connected to the third cylindrical portion 213. In this embodiment, in the connector main body 21, the first to third

cylindrical portions

211, 212, and 213 are provided in the following order from the other side to one side in the axial X direction: the third cylindrical portion 213, the first cylindrical portion 211, and the second cylindrical portion 212.

The first cylindrical portion 211 is a cylindrical portion of the connector 2 that engages with the locking member 3. Specifically, as shown in Figures 2 to 4, the first cylindrical portion 211 has an engaged portion 211a on the outer surface of the first cylindrical portion 211 that can engage with the locking member 3. The engaged portion 211a engages with the locking member 3 (the engaging portion 31 (see Figure 4) described later), thereby connecting the connector 2 and the locking member 3. The engaged portion 211a engages with the engaging portion 31 of the locking member 3 so as to prevent the locking member 3 from coming off the connector 2. In this embodiment, the engaged portion 211a is configured by a male screw provided on the outer surface of the first cylindrical portion 211 and is configured to screw into the engaging portion 31 configured by a female screw (see Figure 7). However, the shape and structure of the engaged portion are not particularly limited as long as it can engage with the engaging portion 31 of the locking member 3 so as to prevent the locking member 3 from coming off the connector 2. The engaged portion and the engaging portion may have other engagement structures, such as a snap-fit joint or a press-fit structure.

In this embodiment, as shown in Figures 2 to 4, the first cylindrical portion 211 has a cylindrical portion 211b on one side in the axial X direction of the first cylindrical portion 211, which is formed by a cylindrical surface on which the engaged portion 211a is not formed. The end portion on the other side in the axial X direction of the ferrule 4 (the end portion of the ferrule cylindrical portion 42 described later) is disposed radially outward of the cylindrical portion 211b. As shown in Figures 2 to 4, the engaged portion 211a of the first cylindrical portion 211 is provided so as to protrude radially outward from the cylindrical portion 211b.

In addition, in this embodiment, as shown in Figs. 2 and 3, the first cylindrical portion 211 has an inserted portion 211c into which the insert portion 43 provided at the other end of the ferrule 4 in the axial X direction is inserted. The inserted portion 211c is configured to engage with the insert portion 43 in the axial X direction when the insert portion 43 is inserted into the inserted portion 211c, and to restrict the ferrule 4 from rotating around the axial X relative to the first cylindrical portion 211. In this embodiment, the inserted portion 211c is provided at a portion in the circumferential direction of the engaged portion 211a formed by a male screw. More specifically, as shown in Figs. 2 and 3, the inserted portion 211c is configured by a recess extending from the cylindrical portion 211b to the other side in the axial X direction at a portion in the circumferential direction of the engaged portion 211a (provided at two positions evenly spaced in the circumferential direction in this embodiment). The inserted portion 211c is configured with a shape and size corresponding to the insert portion 43. As described above, the insertion portion 43 engages with the inserted portion 211c, restricting the rotation of the ferrule 4 around the axis X relative to the first cylindrical portion 211, i.e., the connector 2, thereby preventing the artificial blood vessel VE (see Figs. 7 and 12) sandwiched between the ferrule 4 and the connector 2 (second cylindrical portion 212) from being subjected to a force in a direction rotating around the axis X from the ferrule 4. Therefore, for example, when the locking member 3 is rotated around the axis X to screw into the connector 2, the ferrule 4 is prevented from rotating around the axis X, so that the artificial blood vessel VE is prevented from being twisted or rubbed due to relative rotation with the ferrule 4 (when the ferrule 4 rotates around the axis X, a rotational force is also applied to the artificial blood vessel VE, which may cause the artificial blood vessel VE to be twisted or rubbed, resulting in damage).

The second tubular portion 212, as shown in Figures 2 to 4 and 8, is a tubular portion to which the artificial blood vessel VE (shown by a two-dot chain line in Figures 2 to 4) is attached. As shown in Figure 8, the second tubular portion 212 is fitted inside the artificial blood vessel VE. In other words, the artificial blood vessel VE is fitted into the second tubular portion 212 so as to cover the outside of the second tubular portion 212. As shown in Figures 2 to 4, the second tubular portion 212 is disposed on one side in the direction of axis X with respect to the first tubular portion 211.

In this embodiment, as shown in Figures 2 to 4, the second tubular portion 212 of the connector 2 has an uneven portion 212a on at least a part of the outer periphery of the second tubular portion 212. The uneven portion 212a is a predetermined region of the second tubular portion 212 that has a portion that protrudes radially outward on the outer periphery of the second tubular portion 212 and a portion that is recessed relatively to the protruding portion. As shown in Figure 8, the portion of the uneven portion 212a that protrudes radially outward enters a recess that protrudes radially outward on the inner surface of the artificial blood vessel VE (a recess formed on the inner surface of the peak portion M of the artificial blood vessel VE). In addition, the relatively recessed portion of the uneven portion 212a receives a protrusion that protrudes radially inward on the inner surface of the artificial blood vessel VE (the inner surface of the valley portion V of the artificial blood vessel VE). As a result, when the artificial blood vessel VE is attached (covered) to the second cylindrical portion 212, the artificial blood vessel VE is prevented from moving in one direction (the right side in FIG. 8) in the axial direction X relative to the second cylindrical portion 212. Therefore, during the assembly work of the artificial blood vessel VE, the artificial blood vessel VE is prevented from moving in a direction to be removed from the second cylindrical portion 212, improving workability. As will be described later, the artificial blood vessel VE is compressed radially inward from the elastic member 5 in a state in which the peaks M and valleys V of the artificial blood vessel VE are at least partially arranged along the surface of the uneven portion 212a (see FIG. 12). Therefore, irregular deformation of the artificial blood vessel VE, such as thickening in one portion and thinning in another portion, is unlikely to occur, and partial gaps are prevented from occurring between the artificial blood vessel VE and the second cylindrical portion 212. Note that in FIG. 8, the unevenness due to the peaks M and valleys V of the artificial blood vessel VE is illustrated as completely following the unevenness of the uneven portion 212a, but it is not necessary that all the unevennesses fit into each other. When an artificial blood vessel VE having peaks M and valleys V is attached to the uneven portion 212a of the second tubular portion 212, the peaks M and valleys V of the artificial blood vessel VE are at least partially arranged along the uneven portion 212a, and it is obvious to those skilled in the art that the above-mentioned effects can be partially obtained even if all peaks M and valleys V do not follow the uneven portion 212a.

In this embodiment, as shown in FIG. 2 and FIG. 3, the uneven portion 212a is provided along the circumferential direction of the second tubular portion 212. The uneven portion 212a may be configured by a plurality of annular convex portions (a plurality of annular protrusions spaced apart from each other in the axial X direction) or a spiral convex portion (preferably a convex portion having the same pitch as the spiral of the artificial blood vessel VE) extending along the circumferential direction of the second tubular portion 212. The uneven portion may have a portion protruding radially outwardly that is provided continuously in the circumferential direction, or may be divided in the circumferential direction (may have a plurality of circumferential convex portions that extend discontinuously in the circumferential direction). The uneven portion may also be a plurality of point-like convex portions provided in the circumferential direction and the axial X direction. Note that the uneven portion is preferably of a shape and size that corresponds to the peaks M and valleys V of the artificial blood vessel VE.

The uneven portion 212a is provided in a region in the axial X direction where the elastic member 5 described later is disposed (see Figs. 7, 11, and 12). In this embodiment, the uneven portion 212a is provided in the base end region of the second tubular portion 212, which is the other side in the axial X direction, as shown in Figs. 2 to 4. The uneven portion 212a may be provided in a region of the second tubular portion 212 other than the base end region, for example, in the central region in the axial X direction. The base end region may be a region having a length of, for example, 30% or less, preferably 20% or less, of the entire length of the second tubular portion 212 from the end portion on the other side in the axial X direction of the second tubular portion 212 (the position in the axial X direction where the step portion ST described later is provided).

The outer diameter of the uneven portion 212a (the outer diameter of the apex of the portion protruding radially outward) is not particularly limited as long as the artificial blood vessel VE can be attached to the uneven portion 212a and the elastic member 5, ferrule 4, locking member 3, etc. can be arranged radially outward of the attached artificial blood vessel VE. In this embodiment, the outer diameter of the uneven portion 212a is configured to be equal to or smaller than the inner diameter of the elastic member 5 in the unloaded state. In this case, when the elastic member 5 is moved in the axial direction X to be arranged radially outward of the uneven portion 212a, the elastic member 5 can be easily moved. Note that the outer diameter of the uneven portion 212a may be larger than the inner diameter of the elastic member 5 in the unloaded state as long as the elastic member 5 can be arranged radially outward of the uneven portion 212a.

In this embodiment, as shown in FIG. 8, the outer diameter of the first cylindrical portion 211 is larger than the outer diameter of the second cylindrical portion 212, and a step portion ST is provided between the first cylindrical portion 211 and the second cylindrical portion 212. The step portion ST is capable of engaging with the other end of the elastic member 5 in the axial direction, as described below. Specifically, the outer diameter of the step portion ST (the outer diameter of the first cylindrical portion 211 (cylindrical portion 211b) at the position of the step portion ST) is larger than the inner diameter of the elastic member 5 in the unloaded state (the inner diameter at the other end in the axial direction) so that the other end of the elastic member 5 in the axial direction can be engaged. Also, the inner diameter of the step portion ST (the outer diameter of the second cylindrical portion 212 at the position of the step portion ST) is smaller than the inner diameter of the elastic member 5 in the unloaded state (the inner diameter at the other end in the axial direction).

The third cylindrical portion 213 is a portion to which the connecting portion 22 is connected, as shown in Figs. 2 to 4. The shape and structure of the third cylindrical portion 213 are not particularly limited. In this embodiment, as shown in Fig. 4, the third cylindrical portion 213 has a flange portion that protrudes radially outward at the other end in the axial X direction, and is configured to engage with the connecting portion 22 in the axial X direction.

The ferrule 4 is provided between the second cylindrical portion 212 of the connector 2 and the locking member cylindrical portion 32 of the locking member 3 in the radial direction of the locking member 3. Specifically, as shown in Figs. 9 to 12, the ferrule 4 is provided between the second cylindrical portion 212 to which the artificial blood vessel VE is attached and the locking member cylindrical portion 32 of the locking member 3 before the locking member 3 is connected to the connector 2 (and when the locking member 3 is connected to the connector 2). As a result, when the locking member 3 is connected to the connector 2 (for example, but not limited to, when the locking member 3 is rotated in the direction around the axis X relative to the connector 2 to screw the locking member 3 to the connector 2), the ferrule 4 is interposed between the locking member 3 and the artificial blood vessel VE. Therefore, the application of force from the locking member 3 to the artificial blood vessel VE in the direction around the axis X or in the direction of the axis X is suppressed. This suppresses the artificial blood vessel VE from being twisted or rubbed, which would cause damage to the artificial blood vessel VE.

The ferrule 4 is a cylindrical member that can be disposed radially outside the second cylindrical portion 212 and radially inside the locking member cylindrical portion 32. Although details will be described later, in this embodiment, when the locking member 3 moves in the axial X direction relative to the connector 2, the ferrule 4 is pressed in the axial X direction by the locking member 3 against the connector 2, and moves in the axial X direction (see Figures 7 and 11). Specifically, the ferrule 4 is configured to move in the axial X direction relative to the second cylindrical portion 212 by a pressed portion 45 of the ferrule 4 described later being pressed in the axial X direction by a pressing portion 33 of the locking member 3. The ferrule 4 (including the locking portion 44 and the holding portion 46 described later) has an inner diameter larger than the outer diameter of the second cylindrical portion 212 so that it can move in the axial X direction relative to the second cylindrical portion 212 and be disposed at a predetermined position radially outside the second cylindrical portion 212. In addition, the ferrule 4 has an outer diameter smaller than the inner diameter of the locking member 3 (excluding the pressing portion 33 of the locking member 3, which will be described later) so that the locking member 3 can be moved relative to the ferrule 4 in the axial X direction on the radial outside of the ferrule 4 to connect the locking member 3 to the connector 2.

As shown in Figures 7 and 11, the pressed portion 45 is provided on the outer surface of the ferrule 4 and is a portion pressed by the pressing portion 33. In this embodiment, when the pressed portion 45 is pressed radially inward by the pressing portion 33 of the locking member 3, the leg portion 41 of the ferrule 4 is displaced radially inward, as described below (see Figures 7 and 12). Also, in this embodiment, when the pressed portion 45 is pressed in the axial X direction by the pressing portion 33 of the locking member 4, the ferrule 4 moves in the axial X direction from the state shown in Figure 11 to the state shown in Figure 7. There are no particular limitations on the pressed portion 45, so long as it is configured to be pressed radially inward at least by the pressing portion 33. In this embodiment, when the locking member 3 moves in the axial X direction when connecting with the connector 2, the pressed portion 45 is pressed in the axial X direction by the pressing portion 33 to generate a force that displaces the leg portion 41 radially inward and moves the ferrule 4 in the axial X direction. In this embodiment, the pressed portion 45 has a curved surface that can receive a force from the pressing portion 33 including a force component in the axial X direction and a force component toward the radial inside when it comes into contact with the inclined surface SL (see FIG. 11 and FIG. 12) of the pressing portion 33. In this embodiment, the pressed portion 45 is provided at one end of the outer surface of the ferrule 4 in the axial X direction, but the position of the pressed portion 45 is not particularly limited.

2 and 3, the ferrule 4 has an insertion portion 43 that is inserted into the insertion portion 211c provided in the first cylindrical portion 211 of the connector 2. In this embodiment, as described later, the ferrule 4 is arranged outside the second cylindrical portion 212 to which the artificial blood vessel VE is attached (see FIGS. 10 and 11), and the locking member 3 is rotated around the axis X relative to the connector 2 to screw it in, thereby connecting the locking member 3 and the connector 2 (see FIG. 7). At this time, the insertion portion 43 of the ferrule 4 is inserted into the insertion portion 211c of the connector 2, as shown in FIGS. 10 and 11. The insertion portion 43 is configured to engage with the insertion portion 211c around the axis X, and the engagement between the insertion portion 43 and the insertion portion 211c restricts the rotation of the ferrule 4 around the axis X relative to the first cylindrical portion 211. Therefore, the ferrule 4 suppresses the transmission of the rotational force of the locking member 3 to the artificial blood vessel VE that is sandwiched between the ferrule 4 and the first cylindrical portion 211. Therefore, for example, when the locking member 3 rotates about the axis X and is screwed into the connector 2, the rotation of the ferrule 4 about the axis X is suppressed, and damage to the artificial blood vessel VE due to twisting or rubbing that may occur when a rotational force is transmitted to the artificial blood vessel VE can be suppressed.

The shape and structure of the insertion portion 43 are not particularly limited as long as the insertion portion 43 can engage with the inserted portion 211c in the direction around the axis X and restrict the rotation of the ferrule 4 around the axis X relative to the first cylindrical portion 211. In this embodiment, as shown in Figures 2 and 3, the insertion portion 43 is configured by a tongue-shaped portion that protrudes from the other end of the ferrule 4 (the ferrule cylindrical portion 42 described later) in the direction of the axis X.

In this embodiment, as shown in Figs. 2 to 4, the ferrule 4 has flexible legs 41 that can be displaced radially inward (see Figs. 7 and 12). In this embodiment, the ferrule 4 has a ferrule tubular portion 42 on the other side of the legs 41 in the axial X direction. As shown in Figs. 2 and 4, the ferrule 4 has an elastic member arrangement region R in which the elastic member 5 is arranged, a locking portion 44, and a holding portion 46 on the inner surface of the ferrule 4. The material constituting the ferrule 4 is not particularly limited as long as it is a flexible material that can be displaced radially inward by the legs 41 being pressed by the locking member 3. The material of the ferrule 4 may be, for example, a metal material or resin material that can be elastically or plastically deformed, but it is preferable that the material be a metal material that can be elastically deformed, such as titanium, that has biocompatibility.

As shown in Figures 7 and 12, when the locking member 3 and the connector 2 are connected, the legs 41 are displaced radially inward by being pressed radially inward by the pressing portion 33 of the locking member 3. As will be described in detail later, when the legs 41 are pressed radially inward, the elastic member 5 arranged on the radially inner side of the ferrule 4 is pressed radially inward. As a result, the artificial blood vessel VE arranged on the radially outer side of the uneven portion 212a is pressed radially inward by the elastic member 5.

The shape and structure of the leg 41 are not particularly limited as long as the leg 41 has flexibility that allows it to be displaced radially inward. In this embodiment, the ferrule 4 has a cutout CT extending in the axial X direction as shown in Figs. 2 and 3, and the cutout CT allows the leg 41, which is a portion adjacent to the cutout CT in the circumferential direction, to bend radially around the base end of the leg 41 (the boundary between the leg 41 and the ferrule tubular portion 42) as an axis. In this embodiment, the ferrule 4 has a plurality of cutouts CT (three in this embodiment) that extend in the axial X direction from one end of the ferrule 4 in the axial X direction for a predetermined length (for example, 50% to 80% of the length of the ferrule 4 in the axial X direction (length excluding the insertion portion 43)). As a result, the ferrule 4 has a plurality of legs 41 (three in this embodiment) that are divided in the circumferential direction via the cutouts CT.

The position of the leg 41 in the ferrule 4 is not particularly limited as long as the elastic member 5 can be pressed when the leg 41 is displaced radially inward. In this embodiment, the cutout portion CT extends in the vicinity of the elastic member arrangement region R or to the elastic member arrangement region R in the axial X direction. In this case, the base end of the leg 41 is located in the vicinity of the elastic member arrangement region R or in the elastic member arrangement region R. In this case, when the leg 41 is bent radially inward, the base end of the leg 41 and its neighboring region (ferrule tubular portion 42) also easily displace radially inward, making it possible to easily press the elastic member 5. Note that "in the vicinity of the elastic member arrangement region R" can be, for example, an area within 20%, preferably within 10%, of the total length of the ferrule 4 in the axial X direction from one end of the elastic member arrangement region R in the axial X direction (the right end in FIG. 4 (the boundary between the elastic member arrangement region R and the locking portion 44)) toward one side in the axial X direction.

In this embodiment, the cutout portion CT extends linearly in the axial X direction with approximately the same width, but the shape of the cutout portion CT is not particularly limited as long as the leg portion 41 can be displaced radially inward. For example, the cutout portion may extend at an angle to the axial X direction, or may be cut out to have a portion in the axial X direction where the width in the circumferential direction is partially wider.

The elastic member arrangement region R is an area in which the elastic member 5 is arranged on the inner surface of the ferrule 4 as shown in Figures 4, 7, 10 and 12. In this embodiment, the elastic member arrangement region R is an area facing the uneven portion 212a of the second cylindrical portion 212 in which the elastic member 5 is arranged when the locking member 3 and the connector 2 are connected (see Figures 7 and 12). In this embodiment, the elastic member arrangement region R is an end region on the other side in the axial X direction of the inner surface of the ferrule 4. Note that, in this embodiment, one end of the elastic member arrangement region R in the axial X direction is defined by the locking portion 44, and the other side in the axial X direction relative to the locking portion 44 is the elastic member arrangement region R. The position and size of the elastic member arrangement region R can be changed appropriately depending on the position and size of the uneven portion 212a and/or the elastic member 5, and are not particularly limited. For example, the elastic member arrangement region R can be an area having a length of, for example, 30% or less, preferably 20% or less, of the entire length of the ferrule 4 from the other end in the axial direction of the ferrule 4 (the ferrule cylindrical portion 42 excluding the insertion portion 43). In this embodiment, the elastic member arrangement region R is inclined so that the inner diameter becomes larger as it approaches the other end in the axial direction of the X axis, as shown in FIG. 10 and FIG. 12.

7, 9 to 12, the locking portion 44 is provided on the inner surface of the ferrule 4 and configured to be able to engage with one end of the elastic member 5 in the axial X direction. The locking portion 44 abuts against one end of the elastic member 5 in the axial X direction and defines the position of the one end of the elastic member 5 in the axial X direction. In this embodiment, the locking portion 44 compresses the elastic member 5 in the axial X direction when the locking member 3 and the connector 2 are connected, as described later (see FIGS. 10, 12 and 13). The shape and structure of the locking portion 44 are not particularly limited as long as it is able to engage with one end of the elastic member 5 in the axial X direction in the axial X direction. In this embodiment, the locking portion 44 is configured by a protruding portion protruding radially inward from the inner surface of the ferrule 4. In this embodiment, the locking portion 44 is provided in a ring shape that is continuous in the circumferential direction on the inner surface of the ferrule 4, but may be configured by multiple parts that are divided in the circumferential direction. As shown in FIG. 10, the locking portion 44 is configured so that the inner diameter of the locking portion 44 is smaller than the outer diameter of one end of the elastic member 5 in the axial X direction, and is configured to engage with one end face of the elastic member 5 in the axial X direction.

2, 4, 7, 9 to 12, the holding portion 46 is provided on the inner surface of the leg portion 41, and is pressed toward the outer periphery of the second tubular portion 212 so as to hold the outer surface of the artificial blood vessel VE when the leg portion 41 is displaced radially inward by the pressing portion 33. When the holding portion 46 is provided on the ferrule 4, the artificial blood vessel VE is held by the holding portion 46 in addition to the elastic member 5 described later (see FIG. 12). In this case, as shown in FIG. 12, the gap between the artificial blood vessel VE and the second tubular portion 212 is sealed not only in the area sandwiched between the elastic member 5 and the uneven portion 212a, but also at the end of one side in the axial X direction of the ferrule 4. Therefore, the amount of blood leaking from the inside to the outside of the artificial blood vessel VE is reduced by the area sandwiched between the holding portion 46 and the second tubular portion 212, and is further reduced by the area sandwiched between the elastic member 5 and the uneven portion 212a. This further improves the leakage resistance of the artificial blood vessel connection structure 1.

In this embodiment, the holding portion 46 is configured to hold the artificial blood vessel VE by pressing it radially inward toward the outer surface of the second tubular portion 212. More specifically, as shown in Figures 10 and 12, the holding portion 46 has an uneven structure with unevenness formed in the axial X direction. In this case, the uneven structure of the holding portion 46 fits into the uneven structure formed by the peaks M and valleys V of the artificial blood vessel VE, effectively improving the blood leakage resistance. In this embodiment, the holding portion 46 is provided on the inner surface of the tip portion of the leg portion 41. However, the holding portion may be provided in the central portion of the leg portion 41 as long as it is configured to be pressed toward the outer surface of the second tubular portion 212 so as to hold the outer surface of the artificial blood vessel VE. In this embodiment, the holding portion 46 is provided continuously in the circumferential direction on the inner surface of the leg portion 41 as shown in Figure 2. However, the holding portion may be provided only in a portion of the circumferential direction as long as it is configured to be pressed toward the outer surface of the second tubular portion 212 so as to hold the outer surface of the artificial blood vessel VE.

The locking member 3 is a cylindrical member that is connected to the connector 2 (see Figures 5 to 7). As shown in Figure 12, the locking member 3 is connected to the connector 2, whereby the artificial blood vessel VE attached to the connector 2 is fixed to the connector 2. More specifically, the locking member 3 is connected to the connector 2 with the ferrule 4 interposed between the second cylindrical portion 212, to which the artificial blood vessel VE is attached, and the inner surface of the locking member 3. In this embodiment, the locking member 3 is connected to the connector 2 by moving relative to the connector 2 and the ferrule 4 in the axial X direction, as shown in Figures 9, 11, and 7.

As shown in Figures 4 and 9, the locking member 3 has an engaging portion 31 that engages with the engaged portion 211a of the first cylindrical portion 211, and a locking member cylindrical portion 32 that is disposed radially outward from the second cylindrical portion 212. The locking member 3 also has a pressing portion 33 (see Figures 7 and 12) on the inner surface of the locking member cylindrical portion 32 that presses the leg portion 41 radially inward to displace it.

As shown in Figures 7 and 12, the locking member tubular portion 32 is a tubular portion that is disposed radially outward from the second tubular portion 212 and the ferrule 4. In this embodiment, the locking member tubular portion 32 is substantially cylindrical (see Figures 2 and 5). The locking member tubular portion 32 has an inner diameter that is slightly larger than the outer diameter of the ferrule 4, except for the pressing portion 33 portion described below, so that it can be disposed outside the ferrule 4.

The engaging portion 31 engages with the engaged portion 211a of the connector 2 so as to prevent the locking member 3 from coming off the connector 2. The engagement structure between the engaging portion 31 and the engaged portion 211a is not particularly limited as long as the engaging portion 31 and the engaged portion 211a can engage with each other so as to prevent the locking member 3 from coming off the connector 2. In this embodiment, the engaging portion 31 and the engaged portion 211a are configured to engage with each other by screwing. By screwing the engaging portion 31 and the engaged portion 211a, the locking member 3 rotates around the axis X relative to the connector 2 and moves in the axial direction X. In this embodiment, the engaging portion 31 is a female screw provided on the inner surface of the locking member tubular portion 32, and the engaged portion 211a is a male screw provided on the outer surface of the first tubular portion 211 of the connector 2. In this embodiment, the engaging portion 31 is provided at the other end of the inner surface of the locking member tubular portion 32 in the axial direction X. The engagement structure between the engaging portion 31 and the engaged portion 211a may be an engagement structure other than threaded engagement, such as a snap-fit joint or a press-fit structure.

The pressing portion 33 is a portion that presses and displaces the leg portion 41 (pressed portion 45 in this embodiment) of the ferrule 4 radially inward. When the leg portion 41 is pressed radially inward by the pressing portion 33 and displaced, the elastic member 5 can elastically deform radially inward, as described below.

The shape and structure of the pressing portion 33 are not particularly limited as long as the pressing portion 33 can press and displace the leg portion 41 radially inward. In this embodiment, the pressing portion 33 is provided at one end of the inner surface of the locking member 3 in the axial X direction, and protrudes radially inward from other parts of the locking member 3. The pressing portion 33 may be provided at a position other than the one end of the locking member 3 in the axial X direction. In this embodiment, the pressing portion 33 is provided in a ring shape that is continuous in the circumferential direction on the inner surface of the locking member 3. However, the pressing portion 33 may be provided partially in the circumferential direction.

In this embodiment, as shown in Figures 11 and 12, the pressing portion 33 has an inclined surface SL that can convert the force applied from the pressing portion 33 to the pressed portion 45 when the locking member 3 moves in the axial X direction relative to the connector 2 into a force that displaces the legs 41 of the ferrule 4 radially inward and moves the ferrule 4 in the axial X direction. In this case, when the locking member 3 is connected to the connector 2, the legs 41 are displaced radially inward by the action of moving the locking member 3 in the axial X direction relative to the connector 2. Therefore, the legs 41 can be displaced radially inward simply by the action of connecting the locking member 3 to the connector 2, and no special operation is required separately to displace the legs 41. Therefore, the elastic member 5 can be pressed by the radially inward displacement of the legs 41 through the simple connection action of the locking member 3 and the connector 2. 11 and 12, the inclined surface SL of the pressing portion 33 is inclined on the inner surface of the locking member 3 so that the inner diameter becomes smaller as it proceeds to one side in the direction of the axis X. In this embodiment, the inclined surface SL is configured to be able to abut against the pressed portion 45 of the leg portion 41 in an unloaded state (a state in which the leg portion 41 is not displaced radially inward) as shown in FIG. 11. Also, the inclined surface SL is configured to press the pressed portion 45 so that the holding portion 46 can reach a radial position where it presses the artificial blood vessel VE attached to the second tubular portion 212 as shown in FIG. 12.

Note that, if it is possible to displace the leg 41 of the ferrule 4 radially inward when the locking member 3 moves in the axial X direction relative to the connector 2, both the pressing portion 33 and the pressed portion 45 may have an inclined surface, or only the pressed portion 45 may have an inclined surface. In addition, in this embodiment, the pressing portion 33 presses the pressed portion 45 when the locking member 3 moves in the axial X direction relative to the connector 2, but the pressed portion 45 may be pressed at a timing other than when the locking member 3 moves in the axial X direction relative to the connector 2. For example, the pressed portion 45 may be pressed by the locking member 3 contracting in diameter after the locking member 3 is connected to the connector 2 (for example, when the locking member 3 is provided with a mechanism that can contract the locking member 3).

The elastic member 5 is an annular (cylindrical) member made of an elastically deformable material. As described below, the elastic member 5 is pressed by the inner surface of the ferrule 4 to press the artificial blood vessel VE provided at the position of the uneven portion 212a of the second cylindrical portion 212 of the connector 2. As a result, as shown in FIG. 12, the end of the artificial blood vessel VE is clamped between the uneven portion 212a and the elastic member 5 in the radial direction between the ferrule 4 and the second cylindrical portion 212, and the artificial blood vessel VE and the connector 2 are liquid-tightly connected. The material of the elastic member 5 is not particularly limited, but for example, biocompatible rubber or elastomer can be used.

7 and 12, the elastic member 5 is disposed radially outside the uneven portion 212a and radially inside the ferrule 4. Here, "the elastic member 5 is disposed radially outside the uneven portion 212a" means that the elastic member 5 may be disposed radially outside at least a portion of the area in which the uneven portion 212a is provided. Therefore, the elastic member 5 may be provided so as to cover the entire uneven portion 212a, or may be provided so as to cover only a portion of the uneven portion 212a. In this embodiment, the elastic member 5 is provided along the uneven portion 212a in the axial X direction. Here, "provided along the uneven portion 212a in the axial X direction" means that when the elastic member 5 is pressed, it is provided by being deformed to follow the uneven shape of the surface of the uneven portion 212a over a predetermined area in the axial X direction. In this case, when the elastic member 5 is pressed radially inward, the artificial blood vessel VE arranged on the outside of the uneven portion 212a and the surface of the uneven portion 212 come into close contact over a predetermined area in the axial direction X. Therefore, the blood leakage resistance of the artificial blood vessel connection structure 1 is improved.

The width of the elastic member 5 in the axial direction is not particularly limited, but can be, for example, 80 to 120% of the width of the uneven portion 212a in the axial direction (the area where the protruding portion of the uneven portion 212a is provided). It is more preferable that the width of the elastic member 5 in the axial direction is the same as the width of the uneven portion 212a in the axial direction, or is larger than the width of the uneven portion 212a in the axial direction. In this case, the elastic member 5 is disposed radially outward over the entire uneven portion 212a, so that the inner surfaces of the peaks M and valleys V of the artificial blood vessel VE disposed along the entire surface of the uneven portion 212a are pressed by the elastic member 5 and tightly adhere to the entire surface of the uneven portion 212a without any gaps. Therefore, the blood leakage resistance of the artificial blood vessel connection structure 1 can be further improved.

The elastic member 5 may be arranged radially outward of the uneven portion 212a before the ferrule 4 is connected to the connector 2, or may be arranged radially outward of the uneven portion 212a when the elastic member 5 is arranged on the inner surface of the ferrule 4 (elastic member arrangement region R) and configured to move in the axial direction X together with the ferrule 4 to the radially outward direction of the uneven portion 212a.

In this embodiment, the elastic material 5 is formed in a ring (tubular) shape having a predetermined width, as shown in FIG. 2. The outer diameter and inner diameter of the elastic member 5 are not particularly limited as long as the elastic member 5 can be disposed radially outside the uneven portion 212a and radially inside the ferrule 4. In this embodiment, the inner diameter of the elastic member 5 is configured to be larger than the portion of the uneven portion 212a with the largest outer diameter (preferably the portion with the largest outer diameter when the artificial blood vessel VE is disposed outside the uneven portion 212a). In this case, it is possible to easily dispose the elastic member 5 radially outside the uneven portion 212a. In addition, the inner diameter of the elastic member 5 is set to a size such that it comes into contact with the artificial blood vessel VE disposed in the uneven portion 212a when the leg portion 41 is displaced radially inward and the elastic member 5 is pressed. In this embodiment, the elastic member 5 is inclined so that the outer diameter becomes larger toward the other side in the axial X direction, as shown in FIG. 10.

As shown in Figures 10, 12 and 13, when the leg 41 is displaced radially inward by the pressing portion 33, the elastic member 5 is pressed toward the uneven portion 212a by the inner surface of the ferrule 4 and elastically deformed. This makes it possible to improve the leakage resistance of the artificial blood vessel connection structure 1 in a state where the artificial blood vessel VE is connected to the connector 2 with a simple structure. This point will be explained in detail below.

7 and 12, when the legs 41 of the ferrule 4 are pressed radially inward by the pressing portion 33 of the locking member 3, the legs 41 are displaced radially inward. As the legs 41 are displaced radially inward, the inner surface of the ferrule 4 is displaced radially inward to approach the axis X. As a result, the elastic member 5 is pressed radially inward by the inner surface of the ferrule 4. At this time, as shown in FIGS. 12 and 13, the elastic member 5 comes into contact with the outer surface of the artificial blood vessel VE arranged radially outside the uneven portion 212a, and presses the artificial blood vessel VE toward the uneven portion 212a. As a result, as shown in FIGS. 12 and 13, the artificial blood vessel VE, in which the peaks M and valleys V are arranged, is arranged in close contact along the surface of the uneven portion 212a. 12 and 13, the elastic member 5 deforms and enters the space on the outside of the artificial blood vessel VE where the valleys V are provided between adjacent peaks M. Therefore, the gap between the inner surface of the artificial blood vessel VE and the outer surface of the second tubular portion 212 (uneven portion 212a) and the gap between the inner surface of the elastic member 5 and the outer surface of the artificial blood vessel VE are sealed, and the sealed gap becomes an uneven path in the axial direction X, improving the resistance to blood leakage.

In this embodiment, the elastic member 5 is disposed between the locking portion 44 and the step portion ST in the axial X direction, as shown in Figs. 7, 12, and 13. The elastic member 5 is configured to be compressed in the axial X direction when the ferrule 4 is pressed in the axial X direction against the connector 2 by the locking member 3 and moves in the axial X direction (see Figs. 10, 12, and 13). When the elastic member 5 is pressed in the axial X direction, the elastic member 5 has no escape route due to the step portion ST and the locking portion 44 on both sides in the axial X direction, and due to the inner surface of the ferrule 4 on the radially outer side. Therefore, the elastic member 5, which has no escape route, deforms radially inward toward the gap between the protruding portion of the uneven portion 212a and the adjacent protruding portion (in this embodiment, the gap between the ridge portion M and the ridge portion M of the artificial blood vessel VE disposed outside the uneven portion 212a). Therefore, in addition to being displaced radially inward by the legs 41, the elastic member 5 is compressed in the axial direction X, and is deformed radially inward, pressing the artificial blood vessel VE radially inward. This causes the artificial blood vessel VE to be compressed against the uneven portion 212a with a stronger force, further improving the resistance to blood leakage.

In this embodiment, when the locking member 3 is connected to the connector 2 (see FIG. 12), the distance in the axial direction between the step portion ST and the engaging portion 44 is configured to be shorter than the length in the axial direction of the elastic member 5 in an unloaded state. This allows the elastic member 5 to be compressed in the axial direction.

Next, a method for connecting an artificial blood vessel VE will be described using the artificial blood vessel connection structure 1 of this embodiment as an example. Note that the following description is merely an example, and the artificial blood vessel connection structure 1 is not limited to the following description.

First, an artificial blood vessel VE (see FIG. 8) is prepared with peaks M and valleys V formed up to the end. The locking member 3, ferrule 4, and elastic member 5 are attached to the outside of this artificial blood vessel VE in that order (in FIGS. 2 to 4, the connector 2 is removed). Next, as shown in FIGS. 2 to 4 and 8, the end of the artificial blood vessel VE (shown by a two-dot chain line in FIGS. 2 to 4) is attached to the second tubular portion 212 of the connector 2. At this time, the artificial blood vessel VE is moved so that the end of the artificial blood vessel VE reaches a position outside the uneven portion 212a (see FIG. 8). In this state, as shown in FIG. 8, the peaks M and valleys V of the artificial blood vessel VE are arranged along the unevenness of the uneven portion 212a, and the artificial blood vessel VE is less likely to move in the direction of detachment from the second tubular portion 212 (to the right in FIG. 8). Therefore, before the ferrule 4 and locking member 3 are attached to the connector 2, the artificial blood vessel VE is less likely to come off the second cylindrical portion 212, making it easier to attach the ferrule 4 and locking member 3.

Next, the elastic member 5 is moved in the direction of axis X to a position radially outside the uneven portion 212a. After the elastic member 5 is moved radially outside the uneven portion 212a, the ferrule 4 is moved in the direction of axis X toward the connector 2 until the insertion portion 43 of the ferrule 4 is inserted into the inserted portion 211c of the first cylindrical portion 211 of the connector 2 (see FIG. 10). When the insertion portion 43 of the ferrule 4 is inserted into the inserted portion 211c, rotation of the ferrule 4 about axis X relative to the connector 2 is restricted.

In this state, the locking member 3 is moved in the direction of axis X toward the connector 2. When the locking member 3 moves in the direction of axis X toward the connector 2, as shown in FIG. 11, the inclined surface SL of the pressing portion 33 of the locking member 3 comes into contact with the pressed portion 45 of the ferrule 4. When the locking member 3 is moved in the direction of axis X in this state, the pressed portion 45 of the ferrule 4 is pressed by the pressing portion 33 of the locking member 3, causing the leg portion 41 to bend slightly radially inward and the ferrule 4 to move in the direction of axis X. When the engaging portion 31 of the locking member 3 reaches the position of the engaged portion 211a of the connector 2, the locking member 3 is rotated about axis X to screw the locking member 3 into the connector 2. When the locking member 3 is screwed into the connector 2, the locking member 3 moves further in the direction of axis X while rotating about axis X. As a result, the pressed portion 45 of the ferrule 4 receives a further radially inward force from the pressing portion 33 of the locking member 3, the leg 41 is further bent with the base end as a fulcrum, and the tip side of the leg 41 is further displaced radially inward. This bending of the leg 41 displaces the inner surface of the ferrule 4 radially inward, thereby pressing the elastic member 5 radially inward (see arrow AR1 in FIG. 13). Therefore, the peaks M and valleys V of the artificial blood vessel VE arranged along the uneven portion 212a are in close contact with the surface of the uneven portion 212a, and there is almost no gap between the artificial blood vessel VE and the uneven portion 212a. In this embodiment, the locking member 3 moves in the axial direction X, and the ferrule 4 also moves in the axial direction X, as described above. As a result, the locking portion 44 provided on the inner surface of the ferrule 4 presses the elastic member 5 in the axial direction X (see arrow AR2 in FIG. 13). The elastic member 5 sandwiched between the step portion ST and the locking portion 44 in the axial direction is deformed radially inwardly so as to fill the space between the crests M of the artificial blood vessel VE arranged along the uneven portion 212a while being compressed in the axial direction. As a result, the gap between the inner surface of the artificial blood vessel VE and the outer surface of the second tubular portion 212 (uneven portion 212a) and the gap between the inner surface of the elastic member 5 and the outer surface of the artificial blood vessel VE are sealed. As shown in FIG. 13, the sealed gap becomes an uneven path in the axial direction, and blood is less likely to move in the axial direction, improving the blood leakage resistance of the artificial blood vessel connection structure 1. In this embodiment, the elastic member arrangement region R is inclined so that the inner diameter becomes larger as it moves in the other direction in the axial direction, and the elastic member 5 is inclined so that the outer diameter becomes larger as it moves in the other direction in the axial direction, and is configured so that the radial thickness becomes larger as it moves in the other direction in the axial direction. Therefore, when the leg 41 of the ferrule 4 is bent radially inward, the pressing force from the elastic member arrangement region R to the elastic member 5 (arrow AR1 in FIG. 13) tends to act uniformly over the entire length of the elastic member 5 in the axial X direction (it is possible to reduce the deviation of the pressing force at the position in the axial X direction). The sealing performance of the elastic member 5 is proportional to the length in the axial X direction, so it may be set appropriately according to the desired performance. In this embodiment, the inner diameter of the elastic member 5 is configured to be constant in the axial X direction, but the inner diameter of the elastic member 5 may be configured to increase toward the other side in the axial X direction.

In addition, as shown in Figs. 7 and 12, when the locking member 3 is screwed into the connector 2, the artificial blood vessel VE is pressed radially inward by the holding portion 46 having an uneven structure provided on the tip side of the leg portion 41. The holding portion 46 having an uneven structure fits the surface of the peaks M and valleys V of the artificial blood vessel VE, and can effectively improve blood leakage resistance. Thus, in this embodiment, the artificial blood vessel VE is clamped by the elastic member 5 and the uneven portion 212a at the tip of the artificial blood vessel VE, and is clamped by the holding portion 46 and the second tubular portion 212 at a portion a predetermined distance away from the tip. Therefore, blood leakage resistance can be further improved.

The artificial blood vessel connection structure 1, with the artificial blood vessel VE connected in this liquid-tight manner, is then connected to the connection part Ca of the auxiliary artificial heart, which is the connection object C. This connects the artificial blood vessel VE to the connection object C, making it possible to significantly reduce blood leakage at the connection point between the artificial blood vessel VE and the connection object C.

　Although the embodiment of the present invention has been described above, the present invention is not limited to the above embodiment. Note that the above embodiment mainly describes an invention having the following configuration.

(1) An artificial blood vessel connecting structure for connecting an artificial blood vessel to a connection target, the artificial blood vessel connecting structure comprising:
a connector to be connected to the connection target, the connector comprising: a first tubular portion having an engaged portion; and a second tubular portion disposed on one side of the first tubular portion in the axial direction and fitted inside the artificial blood vessel;
a cylindrical locking member including an engaging portion that engages with the engaged portion of the first cylindrical portion and a locking member cylindrical portion that is disposed radially outward from the second cylindrical portion, the locking member being connected to the connector;
a ferrule provided between the second cylindrical portion of the connector and the locking member cylindrical portion of the locking member in a radial direction of the locking member,
the second cylindrical portion of the connector has an uneven portion on at least a part of an outer periphery of the second cylindrical portion,
The artificial blood vessel connection structure further includes an annular elastic member disposed radially outside the uneven portion and radially inside the ferrule,
The ferrule includes a flexible leg portion that is displaceable radially inward,
the locking member includes a pressing portion on an inner surface of the locking member cylindrical portion, the pressing portion pressing the leg portion radially inward to displace the leg portion,
The elastic member is
When the leg portion is displaced radially inward by the pressing portion, the leg portion is pressed toward the concave-convex portion by an inner surface of the ferrule and elastically deformed.
Artificial blood vessel connection structure.

(2) The uneven portion is provided in a base end region of the second tubular portion, the base end region being on the other side in the axial direction,
The elastic member is provided along the uneven portion in the axial direction.
An artificial blood vessel connection structure as described in (1).

(3) When the locking member moves in the axial direction relative to the connector, the ferrule is pressed in the axial direction relative to the connector by the locking member, and moves in the axial direction,
the ferrule has an engaging portion on an inner surface of the ferrule that is engageable with one end of the elastic member in the axial direction,
An outer diameter of the first cylindrical portion is larger than an outer diameter of the second cylindrical portion, and a step portion is provided between the first cylindrical portion and the second cylindrical portion.
the elastic member is disposed between the locking portion and the step portion in the axial direction,
The artificial blood vessel connection structure according to (1) or (2), wherein when the ferrule is pressed axially against the connector by the locking member and moves in the axial direction, the elastic member is compressed in the axial direction.

(4) The ferrule has a pressed portion on an outer surface of the ferrule that is pressed by the pressing portion,
The artificial blood vessel connecting structure according to any one of (1) to (3), wherein the pressing portion of the locking member and/or the pressed portion of the ferrule have an inclined surface that can convert a force applied to the pressed portion from the pressing portion when the locking member moves in the axial direction relative to the connector into a force that displaces legs of the ferrule radially inward and moves the ferrule in the axial direction.

(5) An artificial blood vessel connection structure according to any one of (1) to (4), in which the leg of the ferrule has a holding portion on the inner surface of the leg that is pressed toward the outer periphery of the second tubular portion so as to hold the outer surface of the artificial blood vessel when the leg is displaced radially inward by the pressing portion.

(6) An artificial blood vessel connection structure according to any one of (1) to (5), in which the holding portion has an uneven structure with unevenness formed in the axial direction.

(7) An artificial blood vessel connection structure according to any one of (1) to (6), in which the uneven portion is composed of a plurality of annular or spiral convex portions extending circumferentially around the second tubular portion.

(8) An artificial blood vessel connection structure according to any one of (1) to (7), in which the first cylindrical portion has an inserted portion into which an insert portion provided at the other end of the ferrule in the axial direction is inserted, and the inserted portion is configured to engage with the insert portion in the axial direction to restrict the ferrule from rotating about the axis relative to the first cylindrical portion.

(9) The artificial blood vessel connection structure further includes an artificial blood vessel,
The artificial blood vessel has peaks and valleys alternately formed over the entire length of the artificial blood vessel,
an end portion of the artificial blood vessel is sandwiched between the concave-convex portion and the elastic member between the ferrule and the second cylindrical portion in the radial direction;
An artificial blood vessel connection structure according to any one of (1) to (8).

1 Artificial blood vessel connection structure 2 Connector 21 Connector main body 211 First cylindrical part 211a Engaged part 211b Cylindrical part 211c Inserted part 212 Second cylindrical part 212a Uneven part 213 Third cylindrical part 22 Connecting part 3 Lock member 31 Engagement part 32 Lock member cylindrical part 33 Pressing part 4 Ferrule 41 Leg part 42 Ferrule cylindrical part 43 Insertion part 44 Locking part 45 Pressed part 46 Holding part 5 Elastic member C Connection target Ca Connected part CT Notch part M Mountain Part R Elastic member arrangement area SL Inclined surface ST Step part V Valley part VE Artificial blood vessel X axis

Claims

An artificial blood vessel connecting structure for connecting an artificial blood vessel to a connection target, the artificial blood vessel connecting structure comprising:
a connector to be connected to the connection target, the connector comprising: a first tubular portion having an engaged portion; and a second tubular portion disposed on one side of the first tubular portion in the axial direction and fitted inside the artificial blood vessel;
a cylindrical locking member including an engaging portion that engages with the engaged portion of the first cylindrical portion and a locking member cylindrical portion that is disposed radially outward from the second cylindrical portion, the locking member being connected to the connector;
a ferrule provided between the second cylindrical portion of the connector and the locking member cylindrical portion of the locking member in a radial direction of the locking member,
the second cylindrical portion of the connector has an uneven portion on at least a part of an outer periphery of the second cylindrical portion,
The artificial blood vessel connection structure further includes an annular elastic member disposed radially outside the uneven portion and radially inside the ferrule,
The ferrule includes a flexible leg portion that is displaceable radially inward,
the locking member includes a pressing portion on an inner surface of the locking member cylindrical portion, the pressing portion pressing the leg portion radially inward to displace the leg portion,
The elastic member is
When the leg portion is displaced radially inward by the pressing portion, the leg portion is pressed toward the concave-convex portion by an inner surface of the ferrule and elastically deformed.
Artificial blood vessel connection structure.
The uneven portion is provided in a base end region of the second tubular portion, the base end region being on the other side in the axial direction,
The elastic member is provided along the uneven portion in the axial direction.
The artificial blood vessel connection structure according to claim 1.
the ferrule is configured to be pressed in the axial direction against the connector by the locking member and move in the axial direction when the locking member moves in the axial direction relative to the connector,
the ferrule has an engaging portion on an inner surface of the ferrule that is engageable with one end of the elastic member in the axial direction,
An outer diameter of the first cylindrical portion is larger than an outer diameter of the second cylindrical portion, and a step portion is provided between the first cylindrical portion and the second cylindrical portion.
the elastic member is disposed between the locking portion and the step portion in the axial direction,
2. The artificial blood vessel connection structure according to claim 1, wherein the ferrule is axially pressed against the connector by the locking member, and when the ferrule moves in the axial direction, the elastic member is compressed in the axial direction.
the ferrule has a pressed portion on an outer surface of the ferrule that is pressed by the pressing portion,
4. The artificial blood vessel connecting structure according to claim 3, wherein the pressing portion of the locking member and/or the pressed portion of the ferrule have an inclined surface capable of converting a force applied to the pressed portion from the pressing portion when the locking member moves in the axial direction relative to the connector into a force that displaces legs of the ferrule radially inward and moves the ferrule in the axial direction.
The artificial blood vessel connection structure according to claim 1, wherein the leg of the ferrule has a holding portion on the inner surface of the leg that is pressed toward the outer periphery of the second tubular portion so as to hold the outer surface of the artificial blood vessel when the leg is displaced radially inward by the pressing portion.
The artificial blood vessel connection structure according to claim 5, wherein the holding portion has an uneven structure with unevenness formed in the axial direction.
The artificial blood vessel connection structure according to claim 1, wherein the uneven portion is composed of a plurality of annular or spiral convex portions extending circumferentially around the second tubular portion.
The artificial blood vessel connection structure further includes an artificial blood vessel,
The artificial blood vessel has peaks and valleys alternately formed over the entire length of the artificial blood vessel,
an end portion of the artificial blood vessel is sandwiched between the concave-convex portion and the elastic member between the ferrule and the second cylindrical portion in the radial direction;
The artificial blood vessel connection structure according to any one of claims 1 to 7.