Stent grafts and graft placement devices

Abstract

To provide a stent which can achieve both of stably locking a stent graft to a graft detention device and detaining the stent graft to a desired portion in a living body lumen in a less invasive manner.SOLUTION: A stent graft 100 comprises: a tubular graft 90; and a skeleton part 10. The skeleton part 10 has a plurality of wound parts 15. The plurality of wound parts 15 includes an end wound part which is located on one end in an axial direction. The end wound part includes a plurality of crest parts 24. A portion other than the crest parts 24 in the end wound part is fixed with sewing to the tubular graft 90. The crest parts 24 are not fixed to the tubular graft 90. In such a state that a diameter of the stent graft 100 shrinks, the plurality of crest parts 24 becomes in a protruding state of protruding in the axial direction from one end of the tubular graft 90. In such a state that the diameter of the stent graft 100 expands, the plurality of crest parts 24 becomes in a non-protruding state of being stored in the tubular graft 90.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a stent graft and a graft placement device.

Background Art

[0002] As a stent graft that is transported to a desired site in a biological lumen by a graft placement device (described as a delivery system in the same document) and is placed and used at the desired site, for example, there is one described in Patent Document 1. The stent graft of Patent Document 1 includes a tubular graft (described as a membrane in the same document) and an end winding portion (described as an end skeleton in the same document) disposed at one end in the axial direction of the tubular graft. The end winding portion of Patent Document 1 includes a plurality of ridges, and the plurality of ridges protrude axially from one end of the tubular graft in both the reduced diameter state and the expanded diameter state of the stent graft. The stent graft is connected to the delivery device via the plurality of ridges. Therefore, the stent graft is placed in the biological lumen in a state where these plurality of ridges protrude axially from one end of the tubular graft.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] According to the study of the inventor of the present application, the stent graft of Patent Document 1 has room for improvement from the viewpoint of realizing low invasiveness when placed in a biological lumen.

Means for Solving the Problems

[0005] According to the present invention, there is provided a stent graft to be placed in a biological lumen, A tubular graft formed from graft material, A skeletal structure made of wire, the skeletal structure being arranged coaxially with the tubular graft, Equipped with, The skeletal portion has a plurality of winding portions that are each wound around the circumferential direction of the tubular graft and are positioned at mutually offset locations in the axial direction of the tubular graft. The plurality of winding portions include an end winding portion located at one end in the axial direction, The end winding portion has multiple V-shaped peaks that are convex toward one side, and opposite to the one side. On the other hand It includes a plurality of V-shaped valleys that are convex toward the side, and is formed in a zigzag shape in which the peaks and valleys are arranged alternately in the circumferential direction. The end winding portion is fixed to the tubular graft by sewing in the portion of the end winding portion other than the peak portion, while the peak portion is not fixed to the tubular graft. When the stent graft is in a reduced diameter state, the multiple peaks protrude axially from one end of the tubular graft. When the stent graft is in an expanded state, the multiple peaks are housed within the tubular graft and are in a non-protruding state. the law of nature, When switching from the protruding state to the non-protruding state, the multiple peaks maintain a convex position toward one side, while receding toward the other side relative to the tubular graft in the axial direction. When switching from the non-protruding state to the protruding state, the multiple peaks maintain a convex position toward one side and advance toward the one side relative to the tubular graft in the axial direction. Tent grafts are provided. Furthermore, according to the present invention, a stent graft that is placed in a biological lumen, A tubular graft formed from graft material, A skeletal structure made of wire, the skeletal structure being arranged coaxially with the tubular graft, Equipped with, The skeletal portion has a plurality of winding portions that are each wound around the circumferential direction of the tubular graft and are positioned at mutually offset locations in the axial direction of the tubular graft. The plurality of winding portions include an end winding portion located at one end in the axial direction, The end winding portion includes a plurality of V-shaped peaks that are convex toward one side and a plurality of V-shaped valleys that are convex toward the opposite side of the one side, and is formed in a zigzag shape in which the peaks and valleys are arranged alternately in the circumferential direction. The end winding portion is fixed to the tubular graft by sewing in the portion of the end winding portion other than the peak portion, while the peak portion is not fixed to the tubular graft. When the stent graft is in a reduced diameter state, the multiple peaks protrude axially from one end of the tubular graft. When the stent graft is in an expanded state, the multiple peaks are housed within the tubular graft and are in a non-protruding state. The end winding portion further comprises strut portions that connect adjacent peaks and valleys to each other. The valley portion is fixed to the tubular graft by stitching, and as a result, it cannot be displaced in the axial direction relative to the tubular graft. The provided stent graft is constructed such that the strut portion is displaceable in the axial direction relative to the tubular graft and swingable relative to the tubular graft, and is sewn to the tubular graft.

[0006] Further, according to the present invention, there is provided a stent graft of the present invention and a delivery system for delivering the stent graft to an indwelling site in a biological lumen, and a graft indwelling device for indwelling the stent graft in the biological lumen, wherein in a state where the stent graft is reduced in diameter, the peak portions protrude axially from one end of the tubular graft in a protruding state, and the plurality of peak portions are locked to the delivery system; in a state where the stent graft is expanded in diameter, the peak portions are in a non-protruding state housed in the tubular graft, and there is provided a graft indwelling device in which the plurality of peak portions are detached from the delivery system.

Advantages of the Invention

[0007] According to the present invention, it is possible to achieve both stably locking the stent graft to the graft indwelling device and indwelling the stent graft in the indwelling site of the biological lumen with less invasiveness.

Brief Description of the Drawings

[0008] [Figure 1] It is a schematic plan view of a stent graft according to an embodiment, showing a state where the stent graft is expanded in diameter. [Figure 2] It is a perspective view of an end winding portion in an embodiment, showing a state where the stent graft is expanded in diameter. [Figure 3] It is a partially enlarged view of the tip portion of a stent graft according to an embodiment, showing a state where the stent graft is flattened and expanded in diameter. [Figure 4] It is a partially enlarged view of the tip portion of a stent graft according to an embodiment, showing a state where the stent graft is flattened and reduced in diameter. [Figure 5] It is a partially enlarged view of an end winding portion in an embodiment, showing a state where the end winding portion is flattened and expanded in diameter. [Figure 6] It is a diagram showing the graft indwelling device according to the embodiment, and shows the tip portion of the outer sheath and its peripheral structure. [Figure 7] It is a schematic diagram showing a state where the stent graft according to the embodiment is indwelling in a living body lumen. [Figure 8] It is a partial enlarged view of the tip portion of the stent graft according to Modification 1, and shows a state where the stent graft is flattened and a state where the stent graft is expanded in diameter. [Figure 9] It is a schematic plan view of the stent graft according to Modification 2, and shows a state where the stent graft is expanded in diameter.

Mode for Carrying Out the Invention

[0009] Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1 to 7. In all the drawings, the same components are denoted by the same reference numerals, and the description will be omitted as appropriate. The axial direction of the stent graft 100 (the axial direction of the tubular graft 90) is the vertical direction in FIG. 1. FIGS. 3 and 4 are diagrams showing a state where the stent graft 100 is cut along its axial direction and developed at one location in the circumferential direction, and the left-right direction in FIGS. 3 and 4 corresponds to the circumferential direction of the stent graft 100. Similarly, FIG. 5 is a diagram showing a state where the end winding portion is cut along its axial direction and flattened and developed at one location in the circumferential direction, and the up-down direction in FIG. 5 corresponds to the circumferential direction of the stent graft 100. Further, in FIGS. 1, 3, 4, and 6, the region inside the outer contour line of the tubular graft 90 is represented by a shading of a plurality of dots arranged at equal intervals.

[0010] As shown in FIG. 1, the stent graft 100 according to the present embodiment is a stent graft 100 indwelling in a living body lumen, and includes a tubular graft 90 formed of a graft material and a skeleton portion 10 constituted by a wire 13, the skeleton portion 10 being arranged coaxially with the tubular graft 90. The skeletal portion 10 has a plurality of winding portions 15, each wound around the circumferential direction of the tubular graft 90 and positioned at mutually offset locations in the axial direction of the tubular graft 90. The multiple winding sections 15 include an end winding section (in this embodiment, the first winding section 21, which will be described later) located at one end in the axial direction (in this embodiment, the tip 91a, which will be described later). As shown in Figure 2, the end winding portion includes a plurality of V-shaped peaks 24 that are convex toward one side and a plurality of V-shaped valleys 28 that are convex toward the opposite side, and is formed in a zigzag shape in which the peaks 24 and valleys 28 are arranged alternately in the circumferential direction. Furthermore, as shown in Figure 3, the end winding portion is fixed to the tubular graft 90 by sewing to the portion other than the peak portion 24, while the peak portion 24 is not fixed to the tubular graft 90. When the stent graft 100 is reduced in diameter, multiple peaks 24 protrude axially from one end of the tubular graft 90 (see Figures 4 and 6), and when the stent graft 100 is expanded in diameter, multiple peaks 24 are housed within the tubular graft 90 and are not protruding (see Figures 1 and 3).

[0011] Furthermore, as shown in Figure 6, the graft placement device 200 according to this embodiment comprises the stent graft 100 and a delivery system 210 for delivering the stent graft 100 to the placement site in the biological lumen, and is a graft placement device for placing the stent graft 100 in the biological lumen. When the stent graft 100 is in a reduced diameter state, the peaks 24 protrude axially from one end of the tubular graft 90, and multiple peaks 24 are locked to the delivery system. When the stent graft 100 is in an expanded state, the peaks 24 are housed within the tubular graft 90 and are in a non-protruding state, and multiple peaks 24 detach from the delivery system.

[0012] The contracted state of the stent graft 100 means that the stent graft 100 is compressed radially to the extent that it can exist within the outer sheath 220. The expanded state of the stent graft 100 means that it is at least expanded in diameter than the contracted state, for example, the natural state of the stent graft 100. The stent graft 100 is in a reduced diameter state while it is housed within the tip 211 of the outer sheath 220 (see Figure 6) of the graft placement device 200. When the tip 221 of the outer sheath 220 containing the stent graft 100 is delivered to the placement site in the biological lumen, and the stent graft 100 is detached from the outer sheath 220, the stent graft 100 elastically recovers from its reduced diameter state to its expanded diameter state. In this way, the stent graft 100 can be transported and placed in the placement site in the biological lumen.

[0013] According to this embodiment, when the stent graft 100 is in a reduced diameter state, the multiple peaks 24 protrude axially from one end of the tubular graft 90, allowing the multiple peaks 24 to be locked to the delivery system 210 of the graft implantation device 200. That is, the multiple peaks 24 restrain the delivery system 210 (the tip 240 described later) from the outside, thereby locking the multiple peaks 24 and, consequently, the stent graft 100 to the delivery system 210. Therefore, the stent graft 100 can be delivered to the implantation site in the biological lumen while being stably locked to the delivery system 210. On the other hand, when the stent graft 100 is in an expanded state, the multiple peaks 24 move away from the delivery system 210 outward, releasing the delivery system 210 from its constraints, thus allowing the multiple peaks 24 (and consequently the stent graft 100) to be detached from the delivery system 210. Furthermore, when the stent graft 100 is in an expanded state, the multiple peaks 24 are housed within the tubular graft 90 and remain in a non-protruding state. In other words, the stent graft 100 is placed in the implantation site within the biological lumen in a non-protruding state with the multiple peaks 24 housed within the tubular graft 90. This allows the tubular graft 90 to protect the biological tissue from multiple peaks 24, enabling the stent graft 100 to be placed in the biological lumen in a less invasive manner. Thus, according to this embodiment, it is possible to achieve both the stable locking of the stent graft 100 to the graft placement device 200 and the less invasive placement of the stent graft 100 in the placement site of the biological lumen. Furthermore, since the multiple peaks 24 are housed within the tubular graft 90 in a non-protruding state and placed within the biological lumen, as shown in Figure 7, the stent graft 100 can be positioned near the opening of another biological lumen branching from the said biological lumen, and at a location where interference of the peaks 24 with the opening can be suppressed.

[0014] In the following explanation, the circumferential direction of the tubular graft 90 may be simply referred to as the circumferential direction, and the axial direction of the tubular graft 90 may be simply referred to as the axial direction. Also, for convenience, one side in the axial direction (one end (upward direction in Figure 1)) will be referred to as the tip side, and the other side in the axial direction (the other end (downward direction in Figure 1)) will be referred to as the base end. Furthermore, unless otherwise specified, the positional relationships and shapes of the various parts of the stent graft 100 are described in the context of the stent graft 100 in its expanded diameter state.

[0015] In this embodiment, the skeletal portion 10 is composed of a plurality of rings 16 arranged coaxially with the tubular graft 90 and spaced apart from each other in the axial direction of the tubular graft 90, with each of the plurality of rings 16 constituting a winding portion 15. Note that in Figures 1 and 7, the shapes of the plurality of rings 16 (multiple winding portions 15) are shown in a simplified manner. Furthermore, as shown in Figure 1, the skeletal portion 10 has a plurality of winding portions 15, including a first winding portion 21 located at the tip portion 91 of the tubular graft 90, a plurality of fourth winding portions 51 located at the base portion 92 of the tubular graft 90, and a plurality of second winding portions 31 and a plurality of third winding portions 41 located between the first winding portion 21 and the plurality of fourth winding portions 51. More specifically, in the tubular graft 90, the first winding portion 21, the plurality of second winding portions 31, the plurality of third winding portions 41 and the plurality of fourth winding portions 51 are arranged in this order from the tip side in the axial direction. Each of the multiple winding sections 15 is formed, for example, in a substantially annular shape. The multiple winding sections 15 (the first winding section 21 to the multiple fourth winding sections 51) are formed, for example, with the same diameter, arranged coaxially, and spaced apart from each other in the axial direction. Here, "spaced apart" means that the multiple winding sections 15 are spaced apart in the axial direction at each position in the circumferential direction, and as shown in Figure 1, it is permissible for the entirety of one winding section 15 to overlap in the axial direction with the entirety of another winding section 15 adjacent to that winding section 15. In this embodiment, among the multiple winding sections 15, the first winding section 21 located at the tip 91 of the tubular graft 90 constitutes the end winding section. That is, in this embodiment, the end winding section is located at the tip in the axial direction.

[0016] As shown in Figure 2, the wire 13 constituting the end winding section (first winding section 21) is, for example, two wires 13. The wires 13 constituting the other winding sections 15 are, for example, one wire each. However, each of the multiple winding sections 15 may be composed of one wire or multiple wires. The material of wire 13 is not particularly limited and may be a metal material or a resin material. The wire diameter (outer diameter) of wire 13 is not particularly limited, but is preferably, for example, 0.05 mm or more and 0.55 mm or less.

[0017] As shown in Figures 1 and 2, the first winding section 21 includes a plurality (e.g., six) of peaks 24 and a plurality (e.g., six) of valleys 28, and is formed in a zigzag shape in which the peaks 24 and valleys 28 are arranged alternately in the circumferential direction. Each of the multiple peaks 24 includes a first inclined portion 22 extending in a first inclination direction (upward to the right in Figure 3) and a second inclined portion 23 extending in a second inclination direction opposite to the first inclination direction (upward to the left in Figure 3). Each of the multiple peaks 24 is formed in a convex V shape toward the tip by the first inclined portion 22 and the second inclined portion 23. In addition, in each peak 24, the vertex of the corner at the boundary between one end of the first inclined portion 22 and one end of the second inclined portion 23 constitutes the vertex 24a of the peak 24. Each of the multiple valleys 28 includes a third inclined portion 26 extending in a third inclination direction (downward to the right in Figure 3) and a fourth inclined portion 27 extending in a fourth inclination direction opposite to the third inclination direction (downward to the left in Figure 3). Each of the multiple valleys 28 is formed in a convex V shape toward the base end by the third inclined portion 26 and the fourth inclined portion 27. As shown in Figures 1 and 3, in the axial direction, each of the multiple peaks 24 is positioned closer to the tip than each of the multiple valleys 28. Furthermore, in this embodiment, the multiple peaks 24 are arranged at approximately equal positions in the axial direction, and the multiple valleys 28 are also arranged at approximately equal positions. Furthermore, for example, in the circumferential direction, multiple peaks 24 are arranged at approximately equal intervals from one another, and multiple valleys 28 are also arranged at approximately equal intervals from one another.

[0018] As shown in Figure 3, the first inclined portion 22, the second inclined portion 23, the third inclined portion 26, and the fourth inclined portion 27 are each formed in a substantially straight shape, for example. However, in the present invention, the first inclined portion 22, the second inclined portion 23, the third inclined portion 26, and the fourth inclined portion 27 may each be formed in a curved shape. Furthermore, the corners of each peak 24 (the corners at the boundary between one end of the first inclined section 22 and one end of the second inclined section 23) and the corners of each valley 28 (the corners at the boundary between one end of the third inclined section 26 and one end of the fourth inclined section 27) are formed in a rounded shape.

[0019] In this embodiment, when the stent graft 100 is in a reduced diameter state, at least several (for example, three or more) of the peaks 24 of the stent graft 100 protrude beyond the tip 91a of the tubular graft 90, and preferably all of the peaks 24 protrude. Furthermore, in the reduced diameter state of the stent graft 100, at least a portion of the protruding peak 24 protrudes beyond the tip 91a of the tubular graft 90. Preferably, in the reduced diameter state of the stent graft 100, at least one-third of the axial length of the protruding peak 24 protrudes beyond the tip 91a of the tubular graft 90, more preferably at least half of the axial length of the peak 24 protrudes beyond the tip 91a of the tubular graft 90, and even more preferably the entire peak 24 protrudes beyond the tip 91a of the tubular graft 90. Similarly, in this embodiment, when the stent graft 100 is in an expanded diameter state, at least several (for example, three or more) of the peaks 24 of the stent graft 100 are housed within the tubular graft 90 and are in a non-protruding state, preferably all of the peaks 24 are in a non-protruding state. Furthermore, in the expanded diameter state of the stent graft 100, the non-protruding peaks 24 are housed within the tubular graft 90 (positioned towards the proximal end than the tip 91a of the tubular graft 90) compared to the contracted diameter state of the stent graft 100. Preferably, in the expanded diameter state of the stent graft 100, at least one-third of the axial length of the non-protruding peaks 24 are housed within the tubular graft 90, more preferably at least half of the axial length of the peaks 24 are housed within the tubular graft 90, and even more preferably the entire peaks 24 are housed within the tubular graft 90. Note that "the entire peaks 24 are housed within the tubular graft 90" includes the state in which the apex 24a of the peaks 24 is at the same axial position as the tip 91a of the tubular graft 90.

[0020] Furthermore, as shown in Figures 2 and 3, the end winding section (in this embodiment, the first winding section 21) includes, for example, a strut section 29 that connects adjacent peaks 24 and valleys 28 to each other. The strut portion 29 includes a first strut portion 29a that connects one end 24b of the peak portion 24 to one end 28a of the valley portion 28 adjacent to one side of the peak portion 24, and a second strut portion 29b that connects the other end 24c of the peak portion 24 to the other end 28b of the valley portion 28 adjacent to the other side of the peak portion 24. The first winding section 21 has a shape in which the first strut section 29a, the peak section 24, the second strut section 29b, and the valley section 28 are repeated in this order from left to right in Figure 3. In this embodiment, the strut portion 29 (first strut portion 29a and second strut portion 29b) is formed in a straight line. Furthermore, the strut portion 29 (same as above) is inclined in a direction that displaces toward the tip as it moves from the valley portion 28 side toward the peak portion 24 side. More specifically, the first strut portion 29a is inclined in the upward-right direction in Figure 3, for example, from one end 28a of the corresponding valley portion 28 toward one end 24b of the peak portion 24. The second strut portion 29b is inclined in the upward-left direction in Figure 3, for example, from the other end 28b of the corresponding valley portion 28 toward the other end 24c of the peak portion 24. Each of the multiple peak portions 24 is positioned towards the tip of the strut portion 29. Furthermore, using a virtual line 401 (see Figure 5) perpendicular to the axis of the tubular graft 90 as a reference, the inclination angle of the strut portion 29 (R2 shown in Figure 5) is smaller than the inclination angles of the first inclined portion 22 and the second inclined portion 23 of the peak portion 24. Note that the inclination angle here refers to the inclination angle when the stent graft 100 is cut along its axial direction at one point in the circumferential direction and laid flat (see Figures 3 and 5, etc.). In the axial direction, each first strut portion 29a is positioned at approximately the same location as each other, and each second strut portion 29b is also positioned at approximately the same location as each other.

[0021] In the present invention, for example, in each peak 24, the first inclined portion 22 and the second inclined portion 23 may be set to have equivalent lengths (dimensions in the extending direction) and inclination angles, or they may be set to have different lengths and inclination angles. Similarly, the first inclined portion 22 of each peak 24 may be set to have equivalent lengths and inclination angles, or they may be set to have different lengths and inclination angles. In this embodiment, in each peak 24, the length dimension of the first inclined portion 22 and the length dimension of the second inclined portion 23 are set to be the same length. Furthermore, the first inclined portion 22 of each peak 24 is set to the same length, and the second inclined portion 23 of each peak 24 is also set to the same length. Furthermore, in each individual peak 24, the inclination angle of the first inclined portion 22 with respect to the axis of the tubular graft 90 and the inclination angle of the second inclined portion 23 with respect to the axis are set to be equivalent inclination angles. Furthermore, the first inclined portion 22 of each peak 24 is set to have an equivalent inclination angle, and the second inclined portion 23 of each peak 24 is also set to have an equivalent inclination angle. Similarly, in the present invention, for example, in each valley 28, the third inclined portion 26 and the fourth inclined portion 27 may be set to have equivalent length dimensions (dimensions in the extending direction) and inclination angles, or they may be set to have different length dimensions and inclination angles. Also, the third inclined portion 26 of each valley 28 may be set to have equivalent length dimensions and inclination angles, or they may be set to have different length dimensions and inclination angles. Similarly, the fourth inclined portion 27 of each valley 28 may be set to have equivalent length dimensions and inclination angles, or they may be set to have different length dimensions and inclination angles. In this embodiment, in each valley 28, the length dimension of the third inclined portion 26 and the length dimension of the fourth inclined portion 27 are set to, for example, equivalent lengths. Furthermore, the third inclined portion 26 of each valley 28 is set to the same length, and the fourth inclined portion 27 of each valley 28 is also set to the same length. Furthermore, in each valley 28, the inclination angle of the third inclined portion 26 with respect to the axis of the tubular graft 90 and the inclination angle of the fourth inclined portion 27 with respect to the axis are set to be equivalent inclination angles. Furthermore, the third inclined section 26 of each valley 28 is set to the same inclination angle as the others, and the fourth inclined section 27 of each valley 28 is also set to the same inclination angle as the others.

[0022] Furthermore, in the present invention, for example, each first strut portion 29a and each second strut portion 29b may be set to have the same length dimensions (dimensions in the extending direction) and inclination angles, or they may be set to have different length dimensions and inclination angles. Also, each first strut portion 29a may be set to have the same length dimensions and inclination angles, or they may be set to have different length dimensions and inclination angles. Similarly, each second strut portion 29b may be set to have the same length dimensions and inclination angles, or they may be set to have different length dimensions and inclination angles. In this embodiment, the length dimensions of each first strut portion 29a and each second strut portion 29b are set to be, for example, equivalent in length. Furthermore, each first strut section 29a is set to have the same length dimension as each second strut section 29b. Furthermore, the inclination angle of the first strut section 29a and the inclination angle of the second strut section 29b, with respect to a virtual line 401 (see Figure 5) perpendicular to the axis of the tubular graft 90, are set to be equivalent dimensions. Furthermore, each first strut section 29a is set to have an equivalent inclination angle, and each second strut section 29b is also set to have an equivalent inclination angle.

[0023] Each of the multiple second winding sections 31 has a zigzag shape in which, for example, a first extending section 33 extending in the upward direction to the right in Figure 1 and a second extending section 34 extending in the opposite direction to the extending direction of the first extending section 33 (downward direction to the right in Figure 1) are alternately repeated. In the multiple second winding sections 31, the corner of the boundary between one end of the first extending section 33 and one end of the second extending section 34 adjacent to one side of the first extending section 33 is convex toward the tip, and the corner of the boundary between the other end of the first extending section 33 and the other end of the second extending section 34 adjacent to the other side of the first extending section 33 is convex toward the base end. Furthermore, the multiple third winding sections 41 and the multiple fourth winding sections 51 are, for example, substantially the same shape and dimensions as the second winding section 31. Therefore, the multiple third winding sections 41 and the multiple fourth winding sections 51 also have a zigzag shape in which the first extending section 33 and the second extending section 34 are alternately repeated. In this invention, the second winding section 31, the multiple third winding sections 41, and the multiple fourth winding sections 51 may be formed in different shapes from each other. Furthermore, in this embodiment, the second winding portion 31, the multiple third winding portions 41, and the multiple fourth winding portions 51 are always contained within the tubular graft 90 (i.e., regardless of whether the stent graft 100 is in a reduced diameter state or an expanded diameter state). That is, the second winding portion 31, the multiple third winding portions 41, and the multiple fourth winding portions 51 are located in the axial direction between the tip 91a and the base end 92a of the tubular graft 90.

[0024] In the present invention, for example, in each of the second winding sections 31 to the fourth winding section 51, the first extending section 33 and the second extending section 34 may be set to have equivalent length dimensions (dimensions in the extending direction) and inclination angles, or they may be set to have different length dimensions and inclination angles. Similarly, each first extending section 33 may be set to have equivalent length dimensions and inclination angles, or they may be set to have different length dimensions and inclination angles. In this embodiment, in each of the second winding sections 31 to the fourth winding section 51, the length dimension of each first extension section 33 and the length dimension of each second extension section 34 are set to, for example, equivalent lengths. Furthermore, each first extension portion 33 is set to have the same length dimension as each second extension portion 34. Furthermore, in each of the second winding sections 31 to the fourth winding section 51, the inclination angle of the first extension section 33 with respect to the axis of the tubular graft 90 and the inclination angle of the second extension section 34 with respect to the axis are set to the same dimensions. Furthermore, the inclination angles of each first extension 33 are set to be the same as those of each other, and the inclination angles of each second extension 34 are also set to be the same as those of each other.

[0025] In this invention, the number of winding portions 15 of the skeletal portion 10 is not particularly limited and can be appropriately changed according to the desired dimensions and applications of each part of the stent graft 100.

[0026] As described above, the stent graft 100 includes a tubular graft 90 formed of graft material in addition to the skeletal portion 10. In this embodiment, the skeletal portion 10 is formed to have the same diameter as the tubular graft 90. The tubular graft 90 is formed, for example, in a cylindrical shape. Furthermore, the tubular graft 90 is configured to decrease in diameter as the stent graft 100 decreases in diameter, and to increase in diameter as the stent graft 100 increases in diameter. As shown in Figure 1, in this embodiment, for example, the first winding portion 21, the multiple second winding portions 31, and the multiple fourth winding portions 51 are each fixed to the inner surface (inside) of the tubular graft 90, and each of the multiple third winding portions 41 is fixed to the outer surface (outside) of the tubular graft 90. That is, of the multiple winding portions 15, the winding portions 15 located at the tip portion 91, the proximal portion 92, and their vicinity of the tubular graft 90 are fixed to the inner surface (inside) of the tubular graft 90. This allows the tip portion 91 and the proximal portion 92 of the tubular graft 90 to adhere well to the inner wall surface of the biological lumen when the stent graft 100 is implanted. Note that in Figures 3, 4, and 6, the multiple winding portions 15 are shown with solid lines for convenience. Here, the phrase "formed to have the same diameter as the tubular graft 90" means that if the skeletal part 10 is fixed inside the tubular graft 90, the outer diameter of the skeletal part 10 and the inner diameter of the tubular graft 90 are equal to each other, and if the skeletal part 10 is fixed outside the tubular graft 90, the inner diameter of the skeletal part 10 and the outer diameter of the tubular graft 90 are equal to each other. In this invention, the stent graft 100 comprises two (double) tubular grafts 90, and the skeletal portion 10 may be positioned between the inner circumferential surface of the outer tubular graft 90 and the outer circumferential surface of the inner tubular graft 90.

[0027] The material constituting the tubular graft 90 can be any material that does not allow blood flow to pass through, and examples include natural fibers such as cellulose fibers, cotton, linters, kapok, flax, hemp, ramie, silk, and wool; chemical fibers such as nylon (polyamide), tetron, rayon, cupro, acetate, vinylon, acrylic, polyethylene terephthalate (polyester), polypropylene, polyethylene, PTFE, and silicone; or combinations of two or more of these natural and chemical fibers (such as blends).

[0028] In this embodiment, the valley portion 28 is fixed to the tubular graft 90 by stitching, and as a result, it cannot be displaced axially relative to the tubular graft 90. On the other hand, the strut portion 29 (first strut portion 29a and second strut portion 29b) is sewn to the tubular graft 90 in such a way that it can be displaced in the axial direction relative to the tubular graft 90 and can swing relative to the tubular graft 90. In this context, "impossible to displace" means that the valleys 28 are substantially imposable relative to the tubular graft 90 in the axial direction. More specifically, each valley 28 is more firmly fixed to the tubular graft 90 than the struts 29, and the amount of displacement of the valleys 28 in the axial direction is at least less than the amount of displacement of the peaks 24. In other words, slight displacement of the valleys 28 relative to the tubular graft 90 in the axial direction is permitted. With this configuration, when the stent graft 100 shrinks in diameter, the strut portion 29 swings and moves forward relative to the tubular graft 90 (towards the tip), so that the amount of protrusion of the peak portion 24 can be sufficiently secured. Also, when the stent graft 100 expands in diameter, the strut portion 29 swings and moves backward relative to the tubular graft 90 (towards the base), so that the peak portion 24 can be more reliably housed in the tubular graft 90.

[0029] Furthermore, as shown in Figure 3 and other figures, in this embodiment, the boundary portions of the strut portion 29 with the peak portion 24 (hereinafter referred to as peak-side boundary portions 25a and 25b) are sewn to the tubular graft 90. With this configuration, sufficient distance can be secured from the stitching points of the valley portion 28 (multiple second stitching points 66 described later) to the stitching points of the strut portion 29 (first stitching points 61a, 61b described later). Therefore, the behavior of the strut portion 29 when the stent graft 100 shrinks in diameter can be performed stably, and the amount of protrusion of each peak portion 24 can be set to the desired amount. In other words, the oscillation angle and forward distance of the strut portion 29 when it moves forward (moves toward the tip) while swinging relative to the tubular graft 90 can be made reproducible, and this operation can be performed stably.

[0030] In this embodiment, as shown in Figures 3 and 5, one stitched portion (hereinafter referred to as the first stitched portion 61a) is formed in each first strut portion 29a. More specifically, the first stitched portion 61a is formed at the boundary portion (peak-side boundary portion 25a) of the first strut portion 29a with the peak portion 24. Similarly, one stitched portion (hereinafter referred to as the first stitched portion 61b) is formed in each second strut portion 29b. The first stitched portion 61b is formed at the boundary portion (peak-side boundary portion 25b) of the second strut portion 29b with the peak portion 24. That is, stitched portions (first stitched portions 61a, 61b) are formed on both ends of each peak portion 24. On the other hand, for example, no stitched portions are formed at the boundary portions (hereinafter referred to as valley-side boundary portions 25c, 25d) of the strut portion 29 with the valley portion 28. Furthermore, no stitching is formed at each individual peak 24, and they are not fixed to the tubular graft 90. Therefore, as the strut portion 29 swings and moves back and forth, each peak 24 can also be displaced axially relative to the tubular graft 90. The first stitched portion 61a is formed, for example, in an I-shape. The first stitched portion 61a is inclined in the opposite direction to the inclination direction of the first strut portion 29a (upward to the left in Figure 3). Similarly, the first stitched portion 61b is formed, for example, in an I-shape. The first stitched portion 61b is inclined in the opposite direction to the inclination direction of the second strut portion 29b (upward to the right in Figure 3). In this embodiment, each first strut portion 29a is displaceable and swingable in the axial direction relative to the first stitched portion 61a between the two ends of the corresponding first stitched portion 61a. Similarly, each second strut portion 29b is displaceable and swingable in the axial direction relative to the first stitched portion 61b between the two ends of the corresponding first stitched portion 61b. With this configuration, compared to cases where the stitching portion is formed in an X shape, it is possible to suppress the occurrence of twisting and wrinkling in the formation area of ​​each stitching portion and its vicinity in the tubular graft 90 when the diameter of the tubular graft 90 decreases in conjunction with the diameter of the stent graft 100. As a result, when each peak 24 and strut portion 29 retracts relative to the tubular graft 90 as the diameter of the stent graft 100 decreases, it is possible to suppress the occurrence of twisting and wrinkling in the formation area of ​​each stitching portion and its vicinity in the tubular graft 90.

[0031] On the other hand, in each valley 28, both the third inclined portion 26 and the fourth inclined portion 27 are sewn to the tubular graft 90. In this embodiment, multiple sewing portions (hereinafter referred to as second sewing portions 66) are formed in each of the third inclined portion 26 and the fourth inclined portion 27. As an example, four second sewing portions 66 are formed in each third inclined portion 26, one of which is formed at the boundary portion 26a on the strut portion 29 side of the third inclined portion 26. Similarly, four second sewing portions 66 are formed in each fourth inclined portion 27, one of which is formed at the boundary portion 27a on the strut portion 29 side of the fourth inclined portion 27. In addition, one second sewing portion 66 is formed at the corner of the boundary between the third inclined portion 26 and the fourth inclined portion 27. Each of the multiple second stitching portions 66 is formed in an I-shape. More specifically, among the multiple second stitching portions 66, the second stitching portions 66 formed at the boundary portion 26a and the third inclined portion 26 are inclined, for example, in the opposite direction to the inclination direction of the third inclined portion 26 (upward to the right in Figure 3). Among the multiple second stitching portions 66, the second stitching portions 66 formed at the boundary portion 27a and the fourth inclined portion 27 are inclined, for example, in the opposite direction to the inclination direction of the fourth inclined portion 27 (upward to the left in Figure 3). Furthermore, the second stitching portion 66 formed at the corner of the boundary between the third inclined portion 26 and the fourth inclined portion 27 extends in the axial direction. Each second stitching portion 66 formed on the third inclined portion 26 and each second stitching portion 66 formed on the fourth inclined portion 27 are arranged in a substantially symmetrical shape with respect to each other in the axial direction. In this way, each valley 28 is fixed to the tubular graft 90 by suture at multiple locations within the valley 28.

[0032] For example, each stitched section (first stitched sections 61a, 61b and multiple second stitched sections 66) is formed by stitching together using a single thread member (not shown). Both ends of the thread member forming each stitched section form a knot (not shown) and are fixed to the tubular graft 90. Note that in Figures 1 and 6, the individual stitched sections are omitted for convenience. However, in the present invention, the shape of each stitched portion is not particularly limited and can be set appropriately according to the wire diameter of the wire 13, the material of the tubular graft 90, and so on. Furthermore, the width dimension (W1 shown in Figure 3) of the first stitched portions 61a and 61b is greater than the wire diameter of the strut portion 29. Preferably, the width dimension W1 of the first stitched portions 61a and 61b is 1.5 times or more and 10 times or less the wire diameter of the strut portion 29, and more preferably 2 times or more and 5 times or less the wire diameter. In this embodiment, as an example, the width dimension W1 of the first stitched portions 61a and 61b is 1 mm or more and 2 mm or less. This ensures a degree of freedom of movement for the strut portion 29 relative to the stitched portion (first stitched portion 61a, 61b), thereby ensuring sufficient oscillation angle and movement distance of the strut portion 29 when it moves forward and backward while oscillating relative to the tubular graft 90. Furthermore, the width dimension (W2 shown in Figure 3) of each second stitched portion 66 is equal to or smaller than the width dimension W1 of the first stitched portions 61a and 61b. More specifically, it is preferable that the width dimension W2 of each second stitched portion 66 is smaller than the width dimension W1 of the first stitched portions 61a and 61b. For example, the width dimension W2 of each second stitched portion 66 may be 1 / 2 or less of the width dimension W1 of the first stitched portions 61a and 61b. In this embodiment, as an example, the width dimension W2 of each second stitched portion 66 is 0.2 mm or more and 1 mm or less. This allows each valley portion 28 to be fixed more firmly to the tubular graft 90 than the strut portion 29.

[0033] In this embodiment, when the stent graft 100 shrinks in diameter, the first strut portion 29a pivots at the vertex 30a of the corner of the boundary between the first strut portion 29a and the corresponding valley portion 28, and moves forward relative to the tubular graft 90 while swinging counterclockwise in a direction that rises towards the tip (along the axis of the tubular graft 90). Similarly, the second strut portion 29b pivots at the vertex 30b of the corner of the boundary between the second strut portion 29b and the corresponding valley portion 28, and moves forward relative to the tubular graft 90 while swinging clockwise in a direction that rises towards the tip. As a result, each peak portion 24 moves forward relative to the corresponding first strut portion The ridge portion 24 is pushed upward toward the tip by the ridge portion 29a and the second strut portion 29b, and moves forward relative to the tubular graft 90. At this time, in the circumferential direction, each stitched portion (first stitched portion 61a, 61b and second stitched portion 66) is displaced in a direction that brings them closer together as the diameter of the tubular graft 90 decreases. In addition, each of the first inclined portion 22 and the second inclined portion 23 of the ridge portion 24 also swings in a direction along the axis of the tubular graft 90, with the apex 24a as the pivot point. That is, each of the multiple ridge portions 24 undergoes elastic deformation in a direction that narrows its apex angle (R1 shown in Figure 5). As a result, the multiple ridge portions 24 protrude outward from the tip 91a of the tubular graft 90. Furthermore, as the stent graft 100 expands in diameter, the first strut portion 29a pivots clockwise in a direction perpendicular to the axis of the tubular graft 90 (a direction perpendicular to the axis of the tubular graft 90), with its apex 30a as the pivot point, and retracts relative to the tubular graft 90. Similarly, the second strut portion 29b pivots counterclockwise in a direction perpendicular to the axis of the tubular graft 90, with its apex 30b as the pivot point, and retracts relative to the tubular graft 90. As a result, each crest portion 24 is pulled toward the base by the corresponding first strut portion 29a and second strut portion 29b, and retracts relative to the tubular graft 90. At this time, in the circumferential direction, each stitched portion is displaced away from each other as the tubular graft 90 expands in diameter. Furthermore, the first inclined portion 22 and the second inclined portion 23 of the peak portion 24 also oscillate in a direction perpendicular to the axis of the tubular graft 90, with the apex 24a as the pivot point. That is, each of the multiple peak portions 24 elastically deforms in a direction that widens its apex angle R1. As a result, the multiple peak portions 24 become non-protruding and housed within the tubular graft 90.

[0034] In this embodiment, as described above, the strut portion 29 is formed in a straight line and is inclined in a direction that causes it to displace to one side (in this embodiment, the tip side) as it moves from the valley portion 28 side to the peak portion 24 side. This allows the behavior of the strut portion 29 (the movement of the strut portion 29 as it oscillates and moves forward relative to the tubular graft 90) to be smooth when the stent graft 100 is reduced in diameter. Furthermore, since the strut portion 29 is formed in a straight line, the strut portion 29 can swing and move back and forth smoothly relative to the tubular graft 90 regardless of which part of the strut portion 29 the first stitching portion 61a and 61b is formed in the extending direction of the strut portion 29.

[0035] Furthermore, as an example, when the stent graft 100 is in an expanded state, the distance from the boundary portion (boundary portion 25a, 25b on the ridge side) to one end of the tubular graft 90 (tip 91a in this embodiment) (D1 shown in Figure 3) is greater than the dimension of the ridge portion 24 in the axial direction (L1 shown in Figures 3 and 5). This ensures that, when the stent graft 100 is in an expanded state, the multiple peaks 24 are more reliably contained within the tubular graft 90, resulting in a non-protruding state. In particular, when the stent graft 100 is placed in the implantation site in the biological lumen, the multiple peaks 24 can be more reliably kept in a non-protruding state.

[0036] Furthermore, as shown in Figure 3, it is preferable that the apex angle R1 of the peak portion 24 is 45 degrees or more when the stent graft 100 is in an expanded state. With this configuration, when the stent graft 100 shrinks in diameter, each peak 24 elastically deforms in a direction that narrows its apex angle R1, as described above, but it is possible to ensure a sufficient amount of protrusion of each peak 24 due to this deformation. Furthermore, in the expanded state of the stent graft 100, it is preferable that the apex angle R1 of the peak 24 exceeds 90 degrees. With this configuration, the amount of protrusion of each peak 24 when the stent graft 100 is reduced in diameter can be further ensured. The apex angle R1 of the mountain section 24 here refers to the angle when the stent graft 100 is cut along its axial direction at one point in the circumferential direction and unfolded (see Figures 3 and 5, etc.).

[0037] The following shows an example of preferred dimensions for each part of the stent graft 100 according to this embodiment. The outer diameter of the stent graft 100 is preferably, for example, 12 mm or more and 26 mm or less, and more preferably 22 mm or more and 36 mm or less. The distance D1 from the mountain-side boundary portions 25a and 25b to one end (tip 91a) of the tubular graft 90 is preferably, for example, 1 mm or more and 9 mm or less, and more preferably 3 mm or more and 7 mm or less. The dimension L2 of the end winding portion (first winding portion 21) in the axial direction (see Figure 5) is preferably 5 mm or more and 10 mm or less, and more preferably 7 mm or more and 8 mm or less. The dimension L1 of each peak 24 in the axial direction is preferably, for example, 1 mm or more and 10 mm or less, and more preferably 2 mm or more and 5 mm or less. The apex angle R1 of the mountain section 24 is preferably, for example, 45 degrees or more and 120 degrees or less, and more preferably 60 degrees or more and 100 degrees or less. The inclination angle R2 of the strut portion 29 is preferably, for example, 5 degrees or more and 25 degrees or less, and more preferably 12 degrees or more and 14 degrees or less. The apex angle R3 of the valley 28 is preferably, for example, 20 degrees or more and 45 degrees or less, and more preferably 25 degrees or more and 40 degrees or less. The distance D2 (see Figure 5) from the mountain-side boundary portion 25b (or mountain-side boundary portion 25a) to the peak 24a of the mountain portion 24 is preferably 1.5 mm or more and 15 mm or less, and more preferably 2.5 mm or more and 8 mm or less. The distance D3 (see Figure 5) between the circumferential boundary portions 25a and 25b on the peak side and the vertex 24a of the peak 24 is preferably, for example, 0.7 mm or more and 3.8 mm or less, and more preferably 1.7 mm or more and 2.8 mm or less. The distance D4 between the peak-side boundary portion 25a and the valley-side boundary portion 25c in the circumferential direction (the distance between the peak-side boundary portion 25b and the valley-side boundary portion 25d) (see Figure 5) is preferably, for example, 2.2 mm or more and 5 mm or less, and more preferably 2.7 mm or more and 4.5 mm or less. The distance D5 from the mountain-side boundary portion 25a to the valley-side boundary portion 25c (distance from the mountain-side boundary portion 25b to the valley-side boundary portion 25d) (see Figure 5) is preferably, for example, 1.5 mm or more and 15 mm or less, and more preferably 3.5 mm or more and 8.0 mm or less. The sum of the above-mentioned distances D2 and D5 (the dimension of the portion that contributes to the elongation of the end winding portion when the stent graft 100 shrinks in diameter) is preferably 3 mm or more and 30 mm or less, and more preferably 6.0 mm or more and 16 mm or less. The distance D6 (see Figure 5) from the peak 24a of the peak 24 to the boundary portions 26a and 27a in the axial direction is preferably 3 mm or more and 7 mm or less, and more preferably 4 mm or more and 6 mm or less. The distance D7 (see Figure 3) from the tip 91a of the tubular graft 90 to the apex 24a of the peak 24 in the axial direction is preferably 0.5 mm or more and 5 mm or less, and more preferably 1 mm or more and 4 mm or less.

[0038] In this invention, the number of peaks 24 and valleys 28 in the end winding portion is not particularly limited and can be appropriately set according to the desired dimensions of each part of the stent graft 100. For example, the number of peaks 24 in the end winding portion may be 8, and the number of valleys 28 in the end winding portion may be 8. In this case, an example of preferred dimensions for each part of the stent graft 100 is as follows. The outer diameter of the stent graft 100 is preferably 45 mm or more and 51 mm or less, and more preferably 38 mm or more and 46 mm or less. The distance D1 from the mountain-side boundary portions 25a and 25b to one end (tip 91a) of the tubular graft 90 is preferably, for example, 1 mm or more and 9 mm or less, and more preferably 3 mm or more and 7 mm or less. The dimension L2 of the end winding portion (first winding portion 21) in the axial direction is preferably 5 mm or more and 10 mm or less, and more preferably 7 mm or more and 8 mm or less. The dimension L1 of each peak 24 in the axial direction is preferably, for example, 1 mm or more and 10 mm or less, and more preferably 2 mm or more and 5 mm or less. The apex angle R1 of the mountain section 24 is preferably, for example, 45 degrees or more and 120 degrees or less, and more preferably 60 degrees or more and 100 degrees or less. The inclination angle R2 of the strut portion 29 is preferably, for example, 4 degrees or more and 20 degrees or less, and more preferably 9 degrees or more and 11 degrees or less. The apex angle R3 of the valley 28 is preferably, for example, 20 degrees or more and 45 degrees or less, and more preferably 25 degrees or more and 40 degrees or less. The distance D2 from the mountain-side boundary portion 25b (or mountain-side boundary portion 25a) to the peak 24a of the mountain portion 24 is preferably 1.5 mm or more and 15 mm or less, and more preferably 2.5 mm or more and 8 mm or less. The distance D3 between the circumferential boundary portions 25a and 25b on the peak side and the vertex 24a of the peak 24 is preferably, for example, 1.4 mm or more and 2.8 mm or less, and more preferably 1.9 mm or more and 2.3 mm or less. The distance D4 between the mountain-side boundary portion 25a and the valley-side boundary portion 25c in the circumferential direction (the distance between the mountain-side boundary portion 25b and the valley-side boundary portion 25d) is preferably, for example, 3.0 mm or more and 5.9 mm or less, and more preferably 4.0 mm or more and 4.9 mm or less. The distance D5 from the mountain-side boundary portion 25a to the valley-side boundary portion 25c (the distance from the mountain-side boundary portion 25b to the valley-side boundary portion 25d) is preferably, for example, 2.5 mm or more and 15 mm or less, and more preferably 4.0 mm or more and 10 mm or less. Furthermore, the sum of the above-mentioned distances D2 and D5 (the dimension of the portion that contributes to the elongation of the end winding portion when the stent graft 100 shrinks in diameter) is preferably 4.0 mm or more and 30 mm or less, and more preferably 6.5 mm or more and 18 mm or less. The distance D6 from the vertex 24a of the peak 24 to the boundary portions 26a and 27a in the axial direction is preferably 3 mm or more and 7 mm or less, and more preferably 4 mm or more and 6 mm or less. The distance D7 from the tip 91a of the tubular graft 90 to the apex 24a of the peak 24 in the axial direction is preferably 0.5 mm or more and 5 mm or less, and more preferably 1 mm or more and 4 mm or less.

[0039] The delivery system 210 of the graft placement device 200 includes, for example, an outer sheath 220 formed in the shape of a tube, an inner catheter 230 inserted axially so as to be slidable through the outer sheath 220, and an operating part (not shown) provided at the proximal end of the outer sheath 220. In Figure 6, the outer sheath 220 is shown in a cross-sectional view along its axial direction for convenience, in order to illustrate its internal structure. The outer sheath 220 and the inner catheter 230 are both long, hollow, tubular members. As shown in Figure 6, the inner catheter 230 is inserted into the lumen of the outer sheath 220, and the outer sheath 220 is slidable in its axial direction relative to the inner catheter 230. The tip of the inner catheter 230 constitutes a placement section in which the stent graft 100 is positioned, and the stent graft 100 is housed within the tip 221 of the outer sheath 220 while extrapolated into this placement section. By manipulating the control section, the outer sheath 220 is retracted relative to the inner catheter 230 towards the proximal end, thereby exposing the tip of the inner catheter 230, and consequently the stent graft 100, from the outer sheath 220 and allowing it to be placed in the biological lumen. Here, as described above, when the stent graft 100 is in a reduced diameter state, multiple peaks 24 protrude axially from the tip 91a of the tubular graft 90. This allows a portion of the inner circumferential surface of the tip 221 of the outer sheath 220 to contact the multiple peaks 24 rather than the outer circumferential surface of the tubular graft 90 when the stent graft 100 is housed in the outer sheath 220. As a result, the frictional resistance (release resistance) between the stent graft 100 and the outer sheath 220 when the outer sheath 220 is retracted toward the proximal end can be reduced.

[0040] Furthermore, a tip 240 is provided at the very front of the inner catheter 230. The proximal end of the tip 240 gradually decreases in diameter towards the proximal end. In this embodiment, as an example, the stent graft 100 is secured to the delivery system 210 by wrapping a plurality of peaks 24 around the base end of the tip 240 with a string member 71 (see Figure 6). One end of the string member 71 is led out of the delivery system 210 from the tip side to the base end side through the lumen of the outer sheath 220. Note that in Figure 6, the winding portion of the string member 71 is selectively shown for convenience. Furthermore, as described above, when the stent graft 100 is in a reduced diameter state, the multiple peaks 24 protrude axially from one end of the tubular graft 90. In this embodiment, the multiple peaks 24 are arranged at approximately equal intervals in the circumferential direction. Therefore, the string member 71 can circumferentially restrain the multiple peaks 24 and, consequently, the tip of the stent graft 100. When the multiple peaks 24 are circumferentially restoring by the string member 71, the elastic recovery from a contracted state to an expanded state is restricted at least at the tip of the stent graft 100. With this configuration, even after the stent graft 100 is detached from the outer sheath 220, the contracted state can be maintained at least at the tip of the stent graft 100. Therefore, after accurately positioning the stent graft 100 exposed from the outer sheath 220 at the implantation site in the biological lumen, the string member 71 can be removed from the peaks 24, and the stent graft 100 can be expanded. In other words, the stent graft 100 can be implanted more reliably at the desired site. Furthermore, since the string member 71 can be wound around multiple peaks 24 located on the inner surface of the tubular graft 90 rather than the outer circumference of the tubular graft 90, the outer diameter of the stent graft 100 in its reduced diameter state can be made smaller. Therefore, the stent graft 100 can be delivered to the implantation site in the biological lumen in a less invasive manner.

[0041] Furthermore, the base end of the tip 240 has, for example, a plurality of protrusions (not shown) that project radially outward. The plurality of protrusions are arranged in a circumferential direction, and a plurality of peaks 24 engage with each of the protrusions. In this embodiment, the length dimension of each projection of the tip 240 (the dimension in the axial direction of the tip 240) is preferably 0.3 mm or more and 1 mm or less, and more preferably 0.5 mm or more and 0.8 mm or less. Furthermore, as described above, if the end winding portion has eight peaks 24 and eight valleys 28, the length dimension of each projection of the tip 240 (same as above) is preferably 0.4 mm or more and 1 mm or less, and more preferably 0.6 mm or more and 0.9 mm or less.

[0042] The following describes an example of how to use the graft implantation device 200 of this embodiment. In the following section, we will describe an example in which the graft placement device 200 is used in a procedure to implant a stent graft 100 in the aortic arch 310 and the descending aorta 330 at a site corresponding to an aortic aneurysm 320 (see Figure 7). First, the delivery system 210 is introduced into the biological lumen along a guidewire (not shown). More specifically, the inner catheter 230 is slid from the proximal end to the distal end along the axial direction of the guidewire, while the tip 221 of the outer sheath 220 is advanced to the implantation site (aortic aneurysm 320 and its vicinity). Next, once the tip 221 of the outer sheath 220 has been inserted to the implantation site, the stent graft 100 is implanted. More specifically, first, the outer sheath 220 is retracted towards the proximal end, exposing at least the tip of the stent graft 100 from the outer sheath 220. Then, with the stent graft 100 positioned in the desired location, the string member 71 wrapped around the multiple peaks 24 is removed. This releases the delivery system 210 from the constraints of the multiple peaks 24, and the tip of the stent graft 100 changes from a contracted state to an expanded state. Next, by exposing the entire stent graft 100 from the outer sheath 220, the entire stent graft 100 changes from a reduced diameter state to an expanded diameter state. However, in the present invention, the string member 71 may be removed from the multiple peaks 24 after the entire stent graft 100 has been exposed from the outer sheath 220. In this way, the stent graft 100 is placed in the location of the tubular lumen. In this invention, as described above, the multiple peaks 24 are housed within the tubular graft 90 and placed in the biological lumen in a non-protruding state. Therefore, as shown in Figure 7, interference between the multiple peaks 24 and the openings of the branch vessels 340 branching from the aortic arch 310 can be suppressed. As a result, even with the stent graft 100 in place, procedures on the branch vessels 340 can be performed smoothly.

[0043] <Example 1> Next, we will explain the stent graft 100 according to modified example 1 using Figure 8. The stent graft 100 according to Modification 1 of this embodiment differs from the stent graft 100 according to the above embodiment in the points described below, and is otherwise configured the same as the stent graft 100 according to the above embodiment. Figure 8 shows the stent graft 100 cut along its axial direction at one point in the circumferential direction and unfolded flat. Therefore, the left-right direction in Figure 8 corresponds to the circumferential direction of the stent graft 100. Also, in Figure 8, the tubular graft 90 is represented by a shading of multiple dots arranged at equal intervals.

[0044] In this modified example, as shown in Figure 8, when the stent graft 100 is in an expanded state, the distance D2 from the boundary portion (mountain-side boundary portions 25a, 25b) to the apex 24a of the mountain portion 24 is greater than the distance D1 from the boundary portion to one end of the tubular graft 90 (the tip 91a in this embodiment). With this configuration, the hypotenuse of each peak 24 is sufficiently large compared to the distance D1 from the boundary portion (peak-side boundary portions 25a, 25b) to one end of the tubular graft 90. As a result, when each peak 24 elastically deforms in the direction in which its apex angle R1 narrows (when the stent graft 100 shrinks in diameter), as described above, a sufficient amount of protrusion of the peak 24 due to the deformation can be ensured. In other words, when the stent graft 100 is in a reduced diameter state, a configuration in which multiple peaks 24 protrude axially from one end of the tubular graft 90 can be more reliably realized.

[0045] <Modification 2> Next, a modified example of the embodiment 2, the stent graft 100, will be described using Figure 9. The stent graft 100 according to Modification 2 of this embodiment differs from the stent graft 100 according to the above embodiment in the respects described below, and is otherwise configured the same as the stent graft 100 according to the above embodiment. In Figure 9, the tubular graft 90 is represented by a shading of multiple dots arranged at equal intervals.

[0046] As shown in Figure 9, in this modified example, the skeletal part 10 is formed in a spiral shape. More specifically, in this modified example, the multiple winding sections 15 are formed, for example, by the wire 13 being wound spirally while oscillating in a zigzag pattern in the axial direction. More specifically, the skeletal section 10 is formed by the wire 13 extending around multiple times, sequentially changing stages. The wire 13 extends approximately one turn in the circumferential direction at each stage, each constituting a winding section 15. The spiral skeletal portion 10 extends from the tip 91 to the base 92 of the tubular graft 90, and the winding portion 15 located furthest towards the tip among the multiple winding portions 15 constitutes the end winding portion. The end winding portion, similar to the embodiment, has a plurality of peaks 24, a plurality of valleys 28, and strut portions 29 (first strut portion 29a and strut portion 29b). In this modified example, it is preferable that the multiple peaks 24 are positioned at approximately equal positions in the axial direction, and that the multiple valleys 28 are also positioned at approximately equal positions. Furthermore, it is preferable that the first strut portions 29a are positioned at approximately equal positions in the axial direction, and that the second strut portions 29b are also positioned at approximately equal positions. For example, in this modified example, the entire spiral skeletal portion 10 is fixed to the inner circumferential surface of the tubular graft 90. However, even in this modified example, the stent graft 100 may comprise two (double) tubular grafts 90, with the skeletal portion 10 positioned between the two tubular grafts 90. This configuration allows for the stable attachment of the stent graft 100 to the graft placement device 200, while also enabling less invasive placement of the stent graft 100 in the placement site of the biological lumen.

[0047] The present invention is not limited to the embodiments described above, and includes various modifications, improvements, and other forms as long as the objectives of the present invention are achieved.

[0048] For example, in the present invention, the skeletal portion 10 only needs to have an end winding portion that includes at least a plurality of peaks 24 and a plurality of valleys 28, and the shape of the other winding portions 15 is not limited to the shapes shown in Figures 1 and 10.

[0049] Furthermore, although the above description illustrates an example in which the end winding portion includes a strut portion 29, in the present invention, the end winding portion only needs to include at least a plurality of peaks 24 and a plurality of valleys 28, and does not necessarily need to include a strut portion 29.

[0050] Furthermore, although the above describes an example in which both the multiple valleys 28 and the strut portions 29 are sewn to the tubular graft 90, the present invention is not limited to this example, and it is sufficient if at least one of the strut portions 29 and the valleys 28 is sewn to the tubular graft 90.

[0051] This embodiment encompasses the following technical concepts. (1) A stent graft that is placed in the lumen of a living organism, A tubular graft formed from graft material, A skeletal structure made of wire, the skeletal structure being arranged coaxially with the tubular graft, Equipped with, The skeletal portion has a plurality of winding portions that are each wound around the circumferential direction of the tubular graft and are positioned at mutually offset locations in the axial direction of the tubular graft. The plurality of winding portions include an end winding portion located at one end in the axial direction. The end winding portion includes a plurality of V-shaped peaks that are convex toward one side and a plurality of V-shaped valleys that are convex toward the opposite side of the one side, and is formed in a zigzag shape in which the peaks and valleys are arranged alternately in the circumferential direction. The end winding portion is fixed to the tubular graft by sewing in the portion of the end winding portion other than the peak portion, while the peak portion is not fixed to the tubular graft. When the stent graft is in a reduced diameter state, the multiple peaks protrude axially from one end of the tubular graft. In the expanded state of the stent graft, the multiple peaks are housed within the tubular graft, resulting in a non-protruding stent graft. (2) The stent graft according to (1), wherein the end winding portion further comprises strut portions that connect adjacent peaks and valleys to each other. (3) The valley portion is fixed to the tubular graft by sewing, so that it cannot be displaced in the axial direction relative to the tubular graft. The stent graft according to (2), wherein the strut portion is sutured to the tubular graft in such a manner that it is displaceable in the axial direction relative to the tubular graft and swingable relative to the tubular graft. (4) The stent graft according to (3), wherein the boundary portion of the strut portion with the peak portion is sutured to the tubular graft. (5) The stent graft according to (3) or (4), wherein the strut portion is formed in a straight line and is inclined in a direction that displaces to one side as it moves from the valley side to the peak side. (6) The stent graft according to (4) or (5), wherein, in the expanded state of the stent graft, the distance from the boundary portion to one end of the tubular graft is greater than the dimension of the peak portion in the axial direction. (7) The stent graft according to (4) or (5), wherein, in the expanded state of the stent graft, the distance from the boundary portion to the peak of the peak is greater than the distance from the boundary portion to one end of the tubular graft. (8) The skeletal portion is composed of a plurality of rings arranged coaxially with the tubular graft and spaced apart from each other in the axial direction of the tubular graft, A stent graft according to any one of (1) to (4), wherein each of the plurality of rings constitutes the winding portion. (9) The stent graft according to any one of (1) to (4), wherein the skeletal portion is formed in a spiral shape. (10) A stent graft according to any one of (1) to (4), wherein, when the stent graft is in an expanded state, the apex angle of the peak portion is 45 degrees or more. A graft placement device for placing the stent graft in a biological lumen, comprising a stent graft described in any one of items (1) to (4) and a delivery system for delivering the stent graft to a placement site in a biological lumen, When the stent graft is in a reduced diameter state, the peaks protrude axially from one end of the tubular graft, and the multiple peaks are locked to the delivery system. A graft placement device in which, when the stent graft is in an expanded state, the peaks are housed within the tubular graft and in a non-protruding state, and the multiple peaks detach from the delivery system. [Explanation of Symbols]

[0052] 10 Skeletal parts 13 wires 15 Multiple winding sections 15 16 Multiple rings 21. First winding section (end winding section) 22 1st slope part 23 2nd slope part 24 Yamabe 24a Vertex 24b One end 24c Other end 25a, 25b Mountain side boundary area 25c, 25d Valley side boundary area 26 Third slope 26a Boundary site 27 4th slope 27a Boundary site 28 Tanibe 28a One end 28b Other end 29 Strut section 29a First strut section 29b Second strut section Vertices 30a and 30b 31 Volume 2 Part 33 1st extension part 34 Second extension part 41 Volume 3 Part 51 Volume 4 Part 61a, 61b 1st sewing part 66 Multiple second seams 71 String component 90 Tubular grafts 91 Tip 91a Tip 92 Proximal end 92a proximal end 100 stent grafts 200 Graft Placement Device 210 Delivery System 220 Outer Sheath 221 Tip 230 Inner Catheter 240 tip tips 310 Aortic arch 320 Aortic aneurysm 330 Descending aorta 340 branch vessels 401 virtual line

Claims

1. A stent graft that is placed in the lumen of a living organism, A tubular graft formed from graft material, A skeletal structure made of wire, the skeletal structure being arranged coaxially with the tubular graft, Equipped with, The skeletal portion has a plurality of winding portions that are each wound around the circumferential direction of the tubular graft and are positioned at mutually offset locations in the axial direction of the tubular graft. The plurality of winding portions include an end winding portion located at one end in the axial direction. The end winding portion includes a plurality of V-shaped peaks that are convex toward one side and a plurality of V-shaped valleys that are convex toward the other side opposite to the one side, and is formed in a zigzag shape in which the peaks and valleys are arranged alternately in the circumferential direction. The end winding portion is fixed to the tubular graft by sewing in the portion of the end winding portion other than the peak portion, while the peak portion is not fixed to the tubular graft. When the stent graft is in a reduced diameter state, the multiple peaks protrude axially from one end of the tubular graft. When the stent graft is in an expanded state, the multiple peaks are housed within the tubular graft and are in a non-protruding state. When switching from the protruding state to the non-protruding state, the multiple peaks maintain a convex position toward one side, while receding toward the other side relative to the tubular graft in the axial direction. When switching from the non-protruding state to the protruding state, the plurality of peaks maintain a convex position toward one side while the stent graft advances toward the one side relative to the tubular graft in the axial direction.

2. The stent graft according to claim 1, wherein the end winding portion further comprises strut portions that connect adjacent peaks and valleys to each other.

3. A stent graft that is placed in the lumen of a living organism, A tubular graft formed from graft material, A skeletal structure made of wire, the skeletal structure being arranged coaxially with the tubular graft, Equipped with, The skeletal portion has a plurality of winding portions that are each wound around the circumferential direction of the tubular graft and are positioned at mutually offset locations in the axial direction of the tubular graft. The plurality of winding portions include an end winding portion located at one end in the axial direction. The end winding portion includes a plurality of V-shaped peaks that are convex toward one side and a plurality of V-shaped valleys that are convex toward the opposite side of the one side, and is formed in a zigzag shape in which the peaks and valleys are alternately arranged in the circumferential direction. The end winding portion is fixed to the tubular graft by sewing in the portion of the end winding portion other than the peak portion, while the peak portion is not fixed to the tubular graft. When the stent graft is in a reduced diameter state, the multiple peaks protrude axially from one end of the tubular graft. When the stent graft is in an expanded state, the multiple peaks are housed within the tubular graft and are in a non-protruding state. The end winding portion further comprises strut portions that connect adjacent peaks and valleys to each other. The valley portion is fixed to the tubular graft by stitching, and as a result, it cannot be displaced in the axial direction relative to the tubular graft. The strut portion is a stent graft sutured to the tubular graft in such a state that it is displaceable in the axial direction relative to the tubular graft and swingable relative to the tubular graft.

4. The stent graft according to claim 3, wherein the boundary portion of the strut portion with the peak portion is sutured to the tubular graft.

5. The stent graft according to claim 3 or 4, wherein the strut portion is formed in a straight line and is inclined in a direction that causes it to displace to one side as it moves from the valley side to the peak side.

6. The stent graft according to claim 4, wherein, in the expanded state of the stent graft, the distance from the boundary portion to one end of the tubular graft is greater than the dimension of the peak portion in the axial direction.

7. The stent graft according to claim 4, wherein, in the expanded state of the stent graft, the distance from the boundary portion to the peak of the peak is greater than the distance from the boundary portion to one end of the tubular graft.

8. The skeletal portion is composed of a plurality of rings arranged coaxially with the tubular graft and spaced apart from each other in the axial direction of the tubular graft. The stent graft according to any one of claims 1 to 4, wherein each of the plurality of rings constitutes the winding portion.

9. The stent graft according to any one of claims 1 to 4, wherein the skeletal portion is formed in a spiral shape.

10. A stent graft according to any one of claims 1 to 4, wherein, when the stent graft is in an expanded state, the apex angle of the peak portion is 45 degrees or more.

11. A graft placement device for placing the stent graft in a biological lumen, comprising a stent graft according to any one of claims 1 to 4, and a delivery system for delivering the stent graft to a placement site in a biological lumen, When the stent graft is in a reduced diameter state, the peaks protrude axially from one end of the tubular graft, and the multiple peaks are locked to the delivery system. A graft placement device in which, when the stent graft is in an expanded state, the peaks are housed within the tubular graft and in a non-protruding state, and the multiple peaks detach from the delivery system.

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