JP2008086464A - Self-expandable indwelling stent - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a self-expandable indwelling stent which has sufficient expansion force and excellent follow-up ability to the deformation of a blood vessel. <P>SOLUTION: The indwelling stent 1 is roughly cylindrically and integrally formed by removing parts other than a linear part constituting the stent from a metal pipe capable of being given superelastic characteristics. Then, the stent 1 indicates the superelastic characteristics both before and after insertion into a living body, also each line width of the linear part of the stent 1 is 100 to 170 μm, and the thickness of the linear part is 180 to 230 μm. For the stent, a compression load for compressing the axial direction length of the stent for 20% is 10 to 20 gf. In other words, the stent can be compressed for 20% in the axial direction by the compression load of 10 to 20 gf. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an in-vivo stent for use in the treatment of stenosis or occlusion occurring in lumens of blood vessels, bile ducts, trachea, esophagus, urethra, and other organs.

  Stents are tubular tubes that are placed to expand the stenosis or occlusion site and secure the lumen to treat various diseases caused by stenosis or occlusion of blood vessels or other in vivo lumens. It is a medical device. Since the stent is inserted from the outside of the body into the body, the diameter is small at the time of insertion. The stent is expanded or restored at a target stenosis or occlusion site to increase the diameter, and the lumen is held in a large state. Stents are classified into self-expandable stents and balloon expandable stents according to function and expansion mode. The balloon expandable stent has no expansion function in the stent itself. After inserting the stent into the target site, the balloon is positioned in the stent to expand the balloon, and the stent is expanded (plastic deformation) by the expansion force of the balloon. Fix it in close contact with the inner surface of the lumen.

  This type of stent requires the above-described stent expansion operation. On the other hand, self-expandable stents are basically made of an elastic material and are sized in an expanded final shape. In order to introduce a stent into the body, a self-expandable stent is folded into a small part and placed in a member (mostly a plastic tube) that constrains its shape, and the entire member, ie, the tube, is introduced into the body. When the stent is released from the tube at the target site, the stent expands by itself due to its elasticity.

  As a self-expandable stent, an annular body formed in a substantially zigzag pattern in which a plurality of struts are connected by a plurality of loops is connected to each other by a connecting part to form a substantially cylindrical shape. Has become the mainstream.

JP-T-2006-501942 Special table 2000-506753 gazette Japanese National Patent Publication No. 11-505441 Special table 2003-512888 gazette

The stents of the above-described Patent Documents 1 to 4 are sufficient as vasodilator force, but are not sufficient to follow the deformation of blood vessels.
An object of the present invention is to provide a self-expanding in-vivo stent that has sufficient expansion force and has good followability to deformation of blood vessels.

What achieves the above object is as follows.
(1) A self-expanding in-vivo stent that is substantially cylindrical and integrally formed by removing other than the linear portion constituting the stent from a metal pipe capable of imparting superelastic characteristics, The stent exhibits superelastic characteristics both before and after insertion into the living body, and each line width of the linear portion of the stent is 100 to 170 μm. The stent has a thickness of 180 to 230 μm, and the stent is a self-expanding in-vivo stent having a compressive load of 10 to 20 gf for compressing the axial length of the stent by 20%.
(2) The stent includes a plurality of wavy annular bodies made of the linear portions in the axial direction, and the wavy annular bodies have a plurality of one end sides having apexes on one end side in the axial direction of the stent. The wavy line-shaped annular body having a bent portion and a plurality of other bent portions having apexes on the other end side in the axial direction of the stent and adjacent to the proximal end side in the axial direction of the stent is formed in the axial direction of the stent. A common end having a starting end at or near one apex of the other end side bend in the wavy annular body at one end, and an end between the apex of the other end bend and the apex of the one end bend The in vivo indwelling stent according to (1), wherein the stent has a linear portion, and adjacent wavy annular bodies are integrated by the shared linear portion.
(3) The stent according to (2), wherein the stent includes a start end branch portion formed by the start end portion of the shared linear portion and a terminal branch portion formed by the end portion of the shared linear portion. In vivo indwelling stent.
(4) The indwelling stent according to (2) or (3), wherein a plurality of shared linear portions are provided between the adjacent wavy annular bodies.
(5) A plurality of shared linear portions are provided between the adjacent wavy annular bodies, and the plurality of shared linear portions are opposed to or substantially equiangular with respect to the central axis of the stent. The in-vivo indwelling stent according to any one of (2) to (4), which is formed to be

(6) The apex of the one end side bent portion of the wavy annular body penetrates into a space formed between the other end side bent portions of the adjacent one of the wavy annular bodies, and the other end of the wavy annular body The in vivo indwelling stent according to any one of (2) to (5), wherein the apex of the side bent portion enters a space formed between the one end bent portions of the other adjacent wavy annular body.
(7) The stent includes a first pattern shared linear portion extending obliquely at a predetermined angle with respect to a central axis of the stent, and an inclined portion of the first pattern shared linear portion with respect to the central axis of the stent. The stent for in-vivo indwelling in any one of (2) thru | or (6) provided with the 2nd pattern shared linear part extended in a different direction.
(8) The in-vivo indwelling stent according to (7), wherein the first pattern-sharing linear portion and the second pattern-sharing linear portion are arranged so as to alternate with respect to the axial direction of the stent. .
(9) The second pattern shared linear portion is disposed at a position shifted in an outer peripheral direction of the stent with respect to an arrangement position of the first pattern shared linear portion. In vivo indwelling stent.

(10) One end of the stent is located at the start or end of the shared linear portion of the wavy annular body, and the other end is shared by the wavy annular body adjacent to the wavy annular body on the axial base end side. The in vivo indwelling according to any one of (2) to (9), comprising a bent linear portion that is located at the start or end of the linear portion and has one end-side bent portion and / or the other end-side bent portion. Stent.
(11) The stent for in-vivo placement according to any one of (2) to (10), wherein the stent includes a connecting portion that connects a wavy annular body located at both ends and a neighboring wavy annular body. .
(12) In the stent, between the wavy annular bodies adjacent to the wavy annular bodies located at both ends, more shared linear portions are provided than between the other portions of the wavy annular bodies (2). Thru | or the stent for indwelling in any one of (11).
(13) The stent includes a contrast marker provided at an end portion of the stent, and an end portion of the contrast marker placement portion does not protrude from the end portion of the stent (1) to (12) The stent for in-vivo in any one of Claims.
(14) The stent includes a contrast marker provided at an end of the stent, and further includes two legs that extend from the marker placement site toward the center of the stent and are spaced apart from each other. The indwelling stent according to any one of (1) to (13), wherein, in the contracted state, the two leg portions are substantially parallel to the linear portions that are separated and close to each other.

The in vivo indwelling stent of the present invention is a self-expanding in vivo indwelling substantially cylindrical and integrally formed by removing other than the linear part constituting the stent from a metal pipe capable of imparting superelastic characteristics. The stent has superelastic characteristics both before and after insertion into the living body, and each line width of the linear portion of the stent is 100 to 170 μm. Yes, the thickness of the linear portion is 180 to 230 μm, and the stent has a compressive load of 10 to 20 gf for compressing the axial length of the stent by 20%.
For this reason, since it has sufficient expansion force and is deformed in the axial direction with a low load, it is easy to expand and contract in the axial direction of the stent, and has good followability to the deformation of the blood vessel. For example, it is particularly suitable for implantation into a rapidly expanding or contracting blood vessel such as a superficial femoral artery or a lower limb artery such as a popliteal artery.

A self-expanding in-vivo stent according to an embodiment of the present invention will be described with reference to the embodiments shown in the drawings.
FIG. 1 is a front view of a self-expanding in-vivo stent according to an embodiment of the present invention. FIG. 2 is a development view of the stent shown in FIG. FIG. 3 is a development view of the stent in a state where the diameter of the stent shown in FIG. 1 is reduced.

The stent 1 for self-expanding in-vivo of the present invention is substantially cylindrical and integrally formed by removing other than the linear portion constituting the stent from a metal pipe capable of imparting superelastic characteristics. The stent 1 exhibits superelastic characteristics both before and after insertion into the living body, and each line width of the linear portion of the stent 1 is 100 to 170 μm. The thickness is 180-230 μm.
Furthermore, the stent has a compressive load of 10 to 20 gf for compressing the axial length of the stent by 20%. In other words, the stent of the present invention can compress the stent 20% in the axial direction by a compressive load of 10 to 20 gf.
In addition, as a stent of this invention, it is preferable that a stent can be compressed 20% to an axial direction by the compressive load of 12-14gf. Moreover, it is preferable that the stent of this invention can compress a stent 20% or more to an axial direction with the compressive load of 10-20 gf.

As shown in FIGS. 1 to 3, the self-expanding in-vivo stent 1 of this embodiment includes a plurality of wavy annular bodies 2 in the axial direction, and the wavy annular body 2 is the axis of the stent 1. A plurality of one-end bent portions having apexes 2a on one end side in the direction and a plurality of other end-side bent portions having apexes 2b on the other end side in the axial direction of the stent 1; The wavy annular body 2 adjacent to the side has a starting end 22 at or near one vertex 2b of the other end side bent portion of the wavy annular body 2 on one end side in the axial direction of the stent 1, and the other end side bent portion. Between the vertices 2b and the vertices 2a of the one-end-side bent portion, the shared linear portion 21 having a terminal end 23, and the adjacent undulated annular bodies are integrated by the shared linear portion 21.
In the stent of this embodiment, by having a partially shared portion, it is composed of a plurality of annular bodies in which adjacent wavy annular bodies are integrated, and does not include a portion provided only as a so-called connection portion, However, since it is a part that exhibits an expansion force and is configured only by a part that can be deformed at the time of compression, compression by a low load is possible.
The stent of this embodiment is a so-called self-expanding stent that is formed in a substantially cylindrical shape, is reduced in diameter when inserted into a living body, and can be restored to a shape before being reduced in diameter when placed in the living body. The external shape at the time of expansion of the stent 1 is shown.
The number of wavy annular bodies 2 forming the stent 1 is 11 in the case shown in FIG. The number of wavy annular bodies 2 varies depending on the length of the stent, but is preferably 2 to 150, and more preferably 5 to 100.

Each wavy-line annular body 2 includes a plurality of one end side bent portions having apexes on one end side in the axial direction of the stent 1 and a plurality of other end side bent portions having apexes on the other end side in the axial direction of the stent 1. And an endless wavy body that is continuous in an annular shape. The one end side bent portions and the other end side bent portions in the annular body 2 are alternately formed, and the numbers thereof are the same. The number of one-end-side bent portions (other-end-side bent portions) in one wavy-line annular body 2 is eight in the case shown in FIG. The number of one-end-side bent portions and the other-end-side bent portions is preferably 4 to 20, and particularly preferably 6 to 12. And the linear body which forms the wavy-line annular body 2 in the stent of Example 1 is always curved, and has very few linear portions. For this reason, since the linear body which forms the annular body 2 has a sufficient length, it exhibits a high expansion force during expansion. In addition, the axial length of the wavy annular body 2 is preferably 1 to 10 mm, and particularly preferably 1.5 to 5 mm.
The wavy annular body 2 adjacent to the proximal end side in the axial direction of the stent 1 has a starting end 22 at or near one vertex 2b of the other end side bent portion of the wavy annular body 2 on one axial end side of the stent 1. And has a shared linear portion 21 having a terminal end 23 between the apex 2a of the other end side bent portion and the apex 2b of the one end side bent portion, and the adjacent wavy annular bodies are integrated by the shared linear portion 21. ing.

Specifically, as shown in FIGS. 1 and 2, the shared linear portion 21 has one apex 2 b of the other end side bent portion in the wavy annular body 2 on one end side in the axial direction of the stent 1 as the start end 22. The start end 22 and the vertex 2b are the same. Further, the shared linear portion 21 has a terminal end 23 between the apexes 2a of the one end side bent portion continuous with the apex 2b (which is also the start end 22). In particular, in this embodiment, the shared linear portion 21 has a terminal end in the vicinity of the middle point between the vertex 2a of the one end side bent portion that is continuous with the vertex 2b (also the starting end 22). The end 23 is preferably located at the midpoint, but it is 1/100 to 49/49 of the total length between the apex 2b (which is also the start 22) and the apex 2a of the one end side bent portion. The position may be on the apex side of about 100. In this case, it is preferable that the position of the terminal end 23 is shifted from the middle point toward the vertex 2a.
Since the stent 1 has the above-described configuration, the stent 1 has a start end branch portion formed by the start end portion of the shared linear portion 21 and a terminal branch portion formed by the end portion of the shared linear portion 21. Specifically, the starting end branching portion is bifurcated toward the one end side with the starting end 22 as a branching point, and the terminal branching portion is directed toward the other end side with the terminal end 23 as a branching point. It has a form that branches into two.

Further, in the stent 1 of this embodiment, as shown in FIG. 2, each wavy-line annular body 2 includes a short line-shaped portion 26 that connects between the terminal end 23 of the shared line-shaped portion 21 and the apex 2a of the one end side bent portion. Have. In addition, the annular body 2 integrated by the annular body 2 having the short linear portion 26 and the shared linear portion 21 is, as shown in FIG. 2, the start end 22 and the other end side bent portion of the shared linear portion 21. It has the short line part 25 which connects between the vertexes 2b, and the long line part 24 which connects between the terminal end 23 of the shared linear part 21, and the other vertex 2b of the other end side bending part.
In this stent, there is no so-called connection portion, and there is no bending failure or expansion force reduction due to the connection portion, and the entire stent exhibits a uniform expansion holding force.
And in the stent 1 of this Example, the some shared linear part 21 is provided between adjacent wavy-line annular bodies. Specifically, two shared linear portions 21 are provided between adjacent wavy annular bodies. The two shared linear portions 21 are formed so as to substantially face the central axis of the stent 1.

Further, as shown in FIG. 2, the apex 2a of the one end side bent portion of the wavy annular body 2 enters the space formed between the apexes 2b of the other end side bent portion of one adjacent wavy annular body. The apex 2b of the other end side bent portion of the wavy annular body 2 penetrates into the space formed between the apexes 2a of the one end side bent portion of the other adjacent wavy annular body.
Furthermore, in the stent 1 of this embodiment, in the contracted state shown in FIG. 3, there are almost no gaps in the circumferential direction, and the elements are arranged. For this reason, it has high coverage.
Moreover, it is preferable to provide the contrast marker 11 like the stent of the Example shown in FIG. 10 thru | or 13 mentioned later. The contrast marker 11 is preferably provided on the end side of the stent. In particular, it is preferable to provide the both ends. Specifically, it is preferable to provide a plurality of markers 11 on both ends of the stent.

In this stent 1, two adjacent annular bodies 2 are integrated by two shared linear portions 21 (first pattern shared linear portions) or two shared linear portions 41 (second pattern shared linear portions). Has been. The two shared linear portions 21 are provided at positions facing the central axis of the stent. Similarly, the two shared linear portions 41 are also provided at positions facing each other with respect to the central axis of the stent.
In this stent 1, the first pattern shared linear portion 21 and the second pattern shared linear portion 41 are arranged so as to alternate with respect to the axial direction of the stent, and the first pattern shared linear portion 21 and the 2nd pattern shared linear part 41 are arrange | positioned so that it may not continue in an axial direction. Specifically, the second pattern shared linear portion 41 is arranged at a position shifted in the outer peripheral direction of the stent with respect to the arrangement position of the first pattern shared linear portion 21.
Further, in the stent 1, the first pattern shared linear portion 21 and the second pattern shared linear portion 41 extend obliquely with respect to the axial direction of the stent, and the directions of both are different.
Specifically, in the stent 1, one annular body 2 has two large wave portions, and the two large wave portions are provided at positions facing the central axis of the stent. Furthermore, two adjacent annular bodies 2 are integrated by two shared linear portions. Furthermore, in this stent 1, the terminal end of the first pattern shared linear portion 21 is connected to the bent portion on the other end side by the linear portion 24. Similarly, the second pattern shared linear portion The terminal end 41 is also connected to the bent portion on the other end side by the linear portion 24. The linear portion 24 is slightly longer than the other linear portions.

In the stent 1, the second pattern shared linear portion 41 adjacent to the first pattern shared linear portion 21 in the axial direction of the stent includes one one end side bent portion and one other end side bent portion. It is provided at a shifted position. Then, the two first pattern sharing linear portions 21 and the two second pattern sharing linear portions 41 adjacent to the proximal end side in the axial direction of the stent are arranged at substantially equal angles with respect to the central axis of the stent 1. It is in a state. For this reason, the stent can express a substantially uniform expansion force as a whole.
Further, in this stent 1, as shown in FIG. 2, the first pattern shared linear portion 21 is arranged so as to be spiral with respect to the axial direction of the stent. The 2nd pattern shared linear part 41 is also arrange | positioned so that it may become spiral shape with respect to the axial direction of a stent.
In addition, as shown in FIG. 2, the stent 1 includes eleven wavy annular bodies arranged in the axial direction of the stent. The first pattern shared linear portion 21 is arranged so as to be spiral with respect to the axial direction of the stent, and similarly, the second pattern shared linear portion 41 is also formed on the stent. It is arranged so as to be spiral with respect to the axial direction. Specifically, every other wavy line-shaped annular body adjacent to each other is connected by two first pattern shared linear portions 21, and each first pattern shared linear portion 21 extends in the axial direction of the stent. It arrange | positions so that it may become a spiral shape. For this reason, two spirals are formed by the first pattern shared linear portion 21. One spiral is composed of five first pattern sharing linear portions 21. Similarly, every other wavy line-shaped annular body (not connected by the first pattern shared linear portion 21) is connected by two second pattern shared linear portions 41, and The 2nd pattern shared linear part 41 is arrange | positioned so that it may become a spiral in the axial direction of a stent. For this reason, two spirals are formed by the second pattern sharing linear portion 41. One spiral is composed of five second pattern sharing linear portions 41.

In addition, as described above, the first pattern shared linear portion 21 and the second pattern shared linear portion 41 extend obliquely with respect to the axial direction of the stent and have different directions. It is preferable that the directions of both are substantially symmetric with respect to the central axis of the stent. By doing so, the stent can develop a substantially uniform expansion force as a whole.
In addition, in the stent 1 of this embodiment, as shown in FIG. 2, the wavy line-shaped annular body 2 is a short line-shaped portion that connects between the terminal end 23 of the first pattern shared line-shaped portion 21 and the apex 2a of the one end side bent portion. 26. The wavy annular body adjacent to the wavy annular body in the axial direction includes a short linear portion 25 that connects between the start end 22 of the first pattern sharing linear portion 21 and the apex 2b of the bent portion on the other end side, It has the short line-shaped part 47 which connects between the terminal 41b of the 2 pattern shared linear part 41, and the vertex of one end side bending part.

As shown in FIGS. 1 and 3, the stent 1 has one end positioned at the start or end of the shared linear portion of the wavy annular body 2 and the other end of the wavy annular body 2 and the axial proximal end. And a bent linear portion that is located at the start or end of the shared linear portion of the wavy-line annular body adjacent to the side and has one end-side bent portion and / or the other end-side bent portion.
The stent 1 according to this embodiment has the above-described configuration, so that the resistance to axial expansion / contraction is small, and the followability to the deformation of blood vessels is good.
Specifically, as shown in FIGS. 1 and 3, the stent 1 of this embodiment has one end positioned at the starting end 22 of the shared linear portion (first pattern shared linear portion 21) of the wavy annular body 2. And the other end is located at the start end 41a of the shared linear portion (second pattern shared linear portion 41) of the wavy annular body adjacent to the wavy-shaped annular body having the shared linear portion and the axial base end side. A bent linear portion (first pattern bent linear portion) 28 is provided. The bent linear portion 28 includes a plurality of bent portions (specifically, four bent portions, more precisely, two one-end-side bent portions and two other-end-side bent portions).
Further, as shown in FIGS. 1 and 3, the stent 1 of this embodiment has one end positioned at the terminal end 23 of the shared linear portion (first pattern shared linear portion 21) of the wavy annular body 2, and the like. A bent linear portion 29 (second pattern) whose end is located at a terminal end 41b of a shared linear portion (second pattern shared linear portion 41) of the wavy annular body adjacent to the wavy annular body on the axial base end side. A bent linear portion). The bent linear portion 29 includes a plurality of bent portions (specifically, one one end side bent portion and one other end side bent portion).
Therefore, the wavy annular body 2 positioned adjacent to the one end of the stent and the axially proximal end side of the wavy annular body 2 has the bent linear portion 28 and the bent linear portion 29 described above.
In addition, as shown in FIGS. 1 and 3, the stent 1 is arranged such that bent linear portions 28 and bent linear portions 29 are alternately arranged in the outer peripheral direction of the stent at one end of the stent. Yes.

The wavy line-shaped body 2 having the bent line-shaped portion 28 and the bent line-shaped portion 29 and the wavy-shaped ring-shaped body 2 adjacent to the proximal end in the axial direction are shared linear portions of the wavy-shaped ring-shaped body 2 at one end. A wavy line-shaped annular body that is located at the start end 41a of the (first pattern shared line-shaped portion 41) and whose other end is adjacent to the base end side in the axial direction. A bent linear portion 31 (third pattern bent linear portion) located at the start end 22 of the first pattern shared linear portion 21) is provided, and one end is a shared linear portion (second pattern) of the wavy annular body 2 The shared linear part 41) is located at the end 41b of the shared linear part 41), and the other end of the shared linear part (first pattern shared linear part 21) of the wavy annular object adjacent to the wavy annular object on the axial base end side. A bent linear portion 32 (fourth pattern bent linear portion) located at the end 23 is provided. Therefore, the wavy line-shaped body 2 having the bent line-shaped portion 28 and the bent line-shaped portion 29 described above and the wavy-shaped ring-shaped body 2 adjacent to the base end side in the axial direction include the bent line-shaped portion 31 and the bent line-shaped portion described above. 32.
The bent linear portion 31 (third pattern bent linear portion) includes a plurality of bent portions (specifically, one one end side bent portion and one other end side bent portion), and the bent linear portion 32 ( The fourth pattern bent linear portion) includes a plurality of bent portions (specifically, four bent portions, more precisely two one-end-side bent portions and two other-end-side bent portions).
In addition, as shown in FIGS. 1 and 3, the stent 1 is arranged such that the bent linear portions 31 and the bent linear portions 32 are alternately arranged in the outer peripheral direction of the stent.
Then, the wavy line-shaped body 2 having the above-described bent line-shaped portion 31 and the bent line-shaped portion 32 and the wavy-shaped ring-shaped body 2 adjacent to the base end side in the axial direction include the above-described bent line-shaped portion 28 and the bent line-shaped portion. 29. In the wavy annular body on the axial base end side from the wavy annular body, the above pattern is repeated.

Further, the stent 10 may have a pattern as shown in FIGS. FIG. 4 is a front view of another embodiment of the stent of the present invention. FIG. 5 is a development view of the stent shown in FIG. 4. FIG. 6 is a development view of the stent in a state where the diameter of the stent shown in FIG. 4 is reduced.
The stent 10 and the stent 1 described above are the same in the basic configuration. In this stent 10, each shared line portion 21 (first pattern shared line portion) is aligned in a substantially straight line with respect to the axial direction of the stent. The part 41 (second pattern shared linear part) is also in a state of being aligned substantially linearly with respect to the axial direction of the stent.
In this stent 10, the number of one-end-side bent portions and the other-end-side bent portions in one annular body 2 is the same as that of the stent 1 (specifically, 9), and 13 annular bodies are arranged in the axial direction. It has been arranged. Two adjacent annular bodies 2 are integrated by three shared linear portions 21 (first pattern shared linear portions) or three shared linear portions 41 (second pattern shared linear portions). The three shared linear portions 21 are provided at substantially equal angles with respect to the central axis of the stent. Similarly, the three shared linear portions 41 are also provided at substantially equal angles with respect to the central axis of the stent.

Further, in the stent 10, the shared linear portion 21 (first pattern shared linear portion) and the shared linear portion 41 (second pattern shared linear portion) extend obliquely with respect to the axial direction of the stent, and both The direction of is different.
More specifically, in the stent 10, the end of the first pattern shared linear portion 21 is connected to the other end side bent portion (not the shared linear portion) by the linear portion 24. Similarly, the terminal end of the second pattern shared linear portion 41 is also connected to the other end side bent portion (not the shared linear portion) by another linear portion. In addition, the linear part 24 connected with a shared linear part is not a clear long linear part compared with the stent 1 mentioned above. The linear portion 24 is slightly longer than the other linear portions. The linear portion 24 may be a long linear portion.

In the stent 10, the second pattern shared linear portion 41 adjacent to the first pattern shared linear portion 21 in the axial direction of the stent has one one end side bent portion and one other end side bent portion. It is provided at a shifted position. Then, the two first pattern shared linear portions 21 and the two second pattern shared linear portions 41 adjacent to each other in the axial direction of the stent are arranged at substantially equal angles with respect to the central axis of the stent 10. ing. For this reason, the stent can express a substantially uniform expansion force as a whole.
Further, as shown in FIG. 5, the stent 10 includes 13 wavy-line annular bodies arranged in the axial direction of the stent. The first pattern shared linear portion 21 is arranged so as to be spiral with respect to the axial direction of the stent, and similarly, the second pattern shared linear portion 41 is also formed on the stent. It is arranged so as to be spiral with respect to the axial direction.
Specifically, one end side wavy annular body (first wavy annular body) and a neighboring wavy annular body (second wavy annular body) are connected by three first pattern sharing linear portions 21. The other end side wavy annular body and the wavy annular body adjacent to the other end side in one end direction are connected by three second pattern sharing linear portions 41. The adjacent wavy-line annular bodies excluding both end portions are continuously connected by three second pattern shared linear portions 41 from one end side, and three first pattern shared linear portions The pattern that two states connected by 21 are continuous is repeated.

Specifically, the wavy annular body (third wavy annular body) adjacent to the second wavy annular body and the wavy annular body (fourth wavy annular body) adjacent to the third wavy annular body are: The three first pattern sharing linear portions 41 are connected. The wavy annular body (fifth wavy annular body) adjacent to the fourth wavy annular body and the wavy annular body (sixth wavy annular body) adjacent to the fifth wavy annular body are the three They are connected by one pattern shared linear portion 21. And said pattern is repeated toward the proximal end direction of a stent.
In addition, in this stent 10, there are six rows formed of a plurality of (specifically, three) first pattern shared linear portions 21 positioned substantially linearly in the axial direction. The six first pattern shared linear portion rows are substantially equiangular with respect to the central axis of the stent. Similarly, in the stent 10, six rows each formed of a plurality (specifically, three) of second pattern shared linear portions 41 positioned substantially linearly in the axial direction are formed. In addition, the six second pattern shared linear portion rows are substantially equiangular with respect to the central axis of the stent.

In addition, as described above, the first pattern shared linear portion 21 and the second pattern shared linear portion 41 extend obliquely with respect to the axial direction of the stent, and both have different directions. In particular, it is preferable that the directions of both are substantially symmetric with respect to the central axis of the stent. By doing so, the stent can develop a substantially uniform expansion force as a whole.
Speaking of the arrangement in the axial direction of the stent, first, three first pattern shared linear portions 21 are present uniformly in the circumferential direction, and in the next stent axial direction, three second pattern shared linear portions 41 are present. It exists evenly in the circumferential direction. In the next stent axial direction, three second pattern shared linear portions 41 are evenly present in the circumferential direction.
In the next stent axial direction, three first pattern shared linear portions 21 are present uniformly in the circumferential direction. If it repeats, it is the characteristic that it has arranged in 21,41,41,21,21,41,41 ....
And the stent 10 of this Example is provided with the above-described form, so that the resistance to axial expansion and contraction is small, and the followability to the deformation of blood vessels is good.

Further, as shown in FIGS. 4 to 6, the stent 10 includes a wavy annular body 2 adjacent to the distal wavy annular body 2 on the axial base end side, and one end of the stent 10 is a shared line of the wavy annular body 2. Of the wavy line-shaped annular body that is located at the start end 22 of the line-shaped part (first pattern shared line-shaped part 21) and whose other end is adjacent to the axial base end side. Bend linear portion (first pattern bend linear portion) 28 located at the start end 41a of the portion (second pattern share linear portion 41), and one end of the common line portion (first pattern share) of the wavy annular body 2 The end of the linear portion 21) and the other end of the shared linear portion (second pattern shared linear portion 41) of the wavy annular body adjacent to the wavy annular body on the axial base end side. A bent linear portion 29 (second pattern bent linear portion) located at 41b is provided. Therefore, the wavy annular body 2 adjacent to the front end wavy annular body 2 and the axially proximal end side has a bent linear portion 28 and a bent linear portion 29.
In the stent 10 of this embodiment, the bent linear portion 28 includes a plurality of bent portions (specifically, one one-end-side bent portion and one other-end-side bent portion). A plurality of bent portions (specifically, one one-end bent portion and one other-end bent portion) are provided. The bent linear portions 28 and the bent linear portions 29 are arranged alternately in the outer peripheral direction of the stent.

The wavy line-shaped body 2 having the bent line-shaped portion 28 and the bent line-shaped portion 29 and the wavy-shaped ring-shaped body 2 adjacent to the proximal end in the axial direction are shared linear portions of the wavy-shaped ring-shaped body 2 at one end. The shared line-shaped portion (second pattern shared line) of the wavy-shaped ring-shaped body 2 that is located at the end 41b of the (first pattern shared line-shaped portion 41) and whose other end is adjacent to the wavy-shaped ring-shaped body and the axial base end side. A bent linear portion 31 (third pattern bent linear portion) located at the starting end 41a of the linear portion 41), and one end thereof is a shared linear portion (second pattern shared linear portion 41) of the wavy annular body 2. ) At the start end 41a, and the other end is located at the end 41b of the shared linear portion (second pattern shared linear portion 41) of the wavy annular body adjacent to the wavy annular body on the axial base end side. A bent linear portion 32 (fourth pattern bent linear portion) is provided. Accordingly, the wavy annular body 2 having the curved portion 28 and the bent linear portion 29 and the wavy annular body 2 adjacent to the axial base end side have the bent linear portion 31 and the bent linear portion 32.
The bent linear portion 31 and the bent linear portion 32 include a plurality of bent portions (specifically, one one end side bent portion and one other end side bent portion).
In addition, as shown in FIGS. 4 to 6, the stent 10 is arranged such that the bent linear portions 31 and the bent linear portions 32 are alternately arranged in the outer peripheral direction of the stent.

And the wavy line-shaped annular body 2 having the bent line-shaped part 31 and the bent line-shaped part 32 described above and the wavy-shaped ring-shaped body 2 adjacent to the axial base end side are shared linear parts of the wavy-shaped ring-shaped body 2 at one end. The shared line-shaped portion (first pattern shared line) of the wavy-shaped ring-shaped body 2 that is located at the terminal end 41b of the (second pattern shared line-shaped portion 41) and whose other end is adjacent to the wavy-shaped ring-shaped body and the axial base end side. A bent line-shaped portion 33 (fifth pattern bent line-shaped portion) located at the terminal end 23 of the wavy-shaped ring portion 2, and one end of which is a shared line-shaped portion (second pattern shared line-shaped portion 41) of the wavy ring-shaped body 2. ) Is located at the start end 41a, and the other end is located at the start end 22 of the shared linear portion (first pattern shared linear portion 21) of the wavy annular body adjacent to the wavy annular body on the axial base end side. A bent linear portion 34 (sixth pattern bent linear portion) is provided. Therefore, the wavy line-shaped body 2 having the bent line-shaped portion 31 and the bent line-shaped portion 32 described above and the wavy-shaped ring-shaped body 2 adjacent to the base end side in the axial direction are the bent line-shaped portion 33 and the bent line-shaped portion described above. 34.
The bent linear portion 33 and the bent portion 34 include a plurality of bent portions (specifically, one one end side bent portion and one other end side bent portion).
Further, as shown in FIGS. 4 to 6, the bent linear portions 33 and the bent linear portions 34 described above are arranged alternately in the outer peripheral direction of the stent.

And the wavy-line annular body 2 which adjoins the wavy-line annular body 2 which has the bending line-shaped part 33 and the bending-line-shaped part 34 mentioned above, and an axial direction base end side is a common linear part of the wavy-line annular body 2 at one end. (First pattern shared line portion 21) The shared line portion (first pattern shared line) of the wavy line ring body 2 is located at the start end 22 of the (first pattern shared line portion 21) and the other end is adjacent to the wavy ring body and the axial base end side. A bent linear portion 35 (seventh pattern bent linear portion) located at the terminal end 23 of the linear portion 21), and one end of the shared linear portion (the first pattern shared linear portion 21) of the wavy annular body 2 is provided. ) And the other end is located at the start end 22 of the shared linear portion (the first pattern shared linear portion 21) of the wavy annular body adjacent to the wavy annular body on the axial base end side. A bent linear portion 36 (eighth pattern bent linear portion) is provided. Therefore, the wavy line-shaped body 2 having the bent line-shaped portion 33 and the bent line-shaped portion 34 described above and the wavy-shaped ring-shaped body 2 adjacent to the base end side in the axial direction are the bent line-shaped portion 35 and the bent line-shaped portion described above. 36.
The bent linear portion 35 and the bent linear portion 36 include a plurality of bent portions (specifically, one one-end bent portion and one other-end bent portion). Further, as shown in FIGS. 4 to 6, the bent linear portions 35 and the bent linear portions 36 described above are arranged alternately in the outer peripheral direction of the stent.
Then, the wavy line-shaped body 2 having the above-described bent line-shaped portion 35 and the bent line-shaped portion 36 and the wavy-shaped ring-shaped body 2 adjacent to the base end side in the axial direction have the above-described pattern of the bent line-shaped portion 28 and the bent line. A shaped portion 29 is provided.

The stent 20 may have a pattern as shown in FIGS. 7 to 9. FIG. 7 is a front view of another embodiment of the stent of the present invention. FIG. 8 is a development view of the stent shown in FIG. FIG. 9 is a development view of the stent in a state where the diameter of the stent shown in FIG. 7 is reduced.
In this stent 20, the number of one end side bent portions and the other end side bent portions in one annular body 2 is 9, and 10 annular bodies are arranged in the axial direction. Two adjacent annular bodies 2 are integrated by three shared linear portions 21 (first pattern shared linear portions) or three shared linear portions 41 (second pattern shared linear portions). The three shared linear portions 21 are provided at substantially equal angles with respect to the central axis of the stent. Similarly, the three shared linear portions 41 are also provided at substantially equal angles with respect to the central axis of the stent.

  In this stent 20, the shared linear portions 21 (first pattern shared linear portions) and the shared linear portions 41 (second pattern shared linear portions) are arranged alternately with respect to the axial direction of the stent. In addition, the shared linear portion 21 (first pattern shared linear portion) and the shared linear portion 41 (second pattern shared linear portion) are arranged so as not to be continuous in the axial direction. Specifically, the shared linear portion 41 (second pattern shared linear portion) is shifted in the outer peripheral direction of the stent with respect to the arrangement position of the shared linear portion 21 (first pattern shared linear portion). Is arranged. Further, the shared linear portions 21 (first pattern shared linear portions) are arranged on a substantially straight line with respect to the axial direction of the stent. Similarly, the shared linear portions 41 (second pattern shared linear portions) are also arranged on a substantially straight line with respect to the axial direction of the stent.

Further, in the stent 20, the shared linear portion 21 (first pattern shared linear portion) and the shared linear portion 41 (second pattern shared linear portion) extend obliquely with respect to the axial direction of the stent, Both directions are different.
More specifically, in the stent 20, the end of the first pattern shared linear portion 21 is connected to the bent portion on the other end side by the linear portion 24. Similarly, the second pattern The end of the shared linear portion 41 is also connected to the bent portion on the other end side by the linear portion 24. The linear portion 24 is slightly longer than the other linear portions. The linear portion 24 may be a long linear portion.

Further, in this stent 20, the second pattern shared linear portion 41 adjacent to the first pattern shared linear portion 21 in the axial direction of the stent includes one one end side bent portion and one other end side bent portion. It is provided at a shifted position. The two first pattern shared linear portions 21 and the two second pattern shared linear portions 41 adjacent to each other in the axial direction of the stent are in a state of being arranged at substantially equal angles with respect to the central axis of the stent 20. ing. For this reason, the stent can express a substantially uniform expansion force as a whole.
In addition, as described above, the first pattern shared linear portion 21 and the second pattern shared linear portion 41 extend obliquely with respect to the axial direction of the stent and have different directions. It is preferable that the directions of both are substantially symmetric with respect to the central axis of the stent. In this way, the stent can develop a substantially uniform expansion force as a whole. In terms of the arrangement in the axial direction of the stent, first, three 1-pattern shared linear portions 21 are present evenly in the circumferential direction, and three second-pattern shared linear portions 41 are present in the next stent axial direction. It exists evenly in the circumferential direction. In the next stent axial direction, three first pattern shared linear portions 21 are present uniformly in the circumferential direction.
In the next stent axial direction, three second pattern shared linear portions 41 are evenly present in the circumferential direction. Repeatedly, 21, 41, 21, 41, 21, 41, 21... Are characteristic.

The stent 20 according to this embodiment has a small resistance to expansion and contraction in the axial direction, and has good followability to the deformation of blood vessels.
In addition, in the stent 20 of this Example, as shown in FIG. 8, the wavy line-shaped annular body 2 has a short line-shaped portion that connects between the terminal end 23 of the first pattern shared line-shaped portion 21 and the apex 2a of the one end side bent portion. 26. The wavy line-shaped annular body adjacent to the wavy line-shaped circular body includes a short line-shaped portion 25 that connects between the apex of the first end 22 of the first pattern shared line-shaped portion 21 and the bent portion on the other end side, and the second pattern shared line. It has the short line-shaped part 47 which connects between the terminal end 41b of the shape part 41, and the vertex of the one end side bending part.

As in the stent 1 described above, the stent 20 has one end at the start end 22 of the shared linear portion (the first pattern shared linear portion 21) of the wavy annular body 2, as shown in FIGS. At the start end 41a of the shared linear part (second pattern shared linear part 41) of the wavy annular object adjacent to the axially proximal end side and the wavy annular object having the other end of the shared linear part The bent linear portion (first pattern bent linear portion) 28 and one end are located at the end 23 of the shared linear portion (first pattern shared linear portion 21) of the wavy annular body 2, and the other end is A bent linear portion 29 (second pattern bent line) located at a terminal end 41b of the shared linear portion (second pattern shared linear portion 41) of the wavy annular member adjacent to the wavy annular member on the axial base end side. Shaped part). Therefore, the wavy annular body 2 positioned adjacent to the one end of the stent and the axially proximal end side of the wavy annular body 2 has the bent linear portion 28 and the bent linear portion 29 described above. Further, the bent linear portions 28 and the bent linear portions 29 are arranged so as to alternate in the outer peripheral direction of the stent.
The wavy line-shaped body 2 having the bent line-shaped portion 28 and the bent line-shaped portion 29 and the wavy-shaped ring-shaped body 2 adjacent to the proximal end in the axial direction are shared linear portions of the wavy-shaped ring-shaped body 2 at one end. A wavy line-shaped annular body that is located at the start end 41a of the (first pattern shared line-shaped portion 41) and whose other end is adjacent to the base end side in the axial direction. A bent linear portion 31 (third pattern bent linear portion) located at the start end 22 of the first pattern shared linear portion 21) is provided, and one end is a shared linear portion (second pattern) of the wavy annular body 2 The shared linear part 41) is located at the end 41b of the shared linear part 41), and the other end of the shared linear part (first pattern shared linear part 21) of the wavy annular object adjacent to the wavy annular object on the axial base end side. A bent linear portion 32 (fourth pattern bent linear portion) located at the end 23 is provided. Therefore, the wavy line-shaped body 2 having the bent line-shaped portion 28 and the bent line-shaped portion 29 described above and the wavy-shaped ring-shaped body 2 adjacent to the base end side in the axial direction include the bent line-shaped portion 31 and the bent line-shaped portion described above. 32. The bent linear portions 31 and the bent linear portions 32 described above are alternately arranged in the outer peripheral direction of the stent.
Each of the bent linear portions 28, 29, 31, and 32 includes a plurality of bent portions (specifically, one one-end bent portion and one other-end bent portion).
Then, the wavy line-shaped body 2 having the above-described bent line-shaped portion 31 and the bent line-shaped portion 32 and the wavy-shaped ring-shaped body 2 adjacent to the base end side in the axial direction include the above-described bent line-shaped portion 28 and the bent line-shaped portion. 29.

Moreover, as a stent, the stent 30 of a pattern as shown to FIG. 10 and FIG. 11 may be sufficient. FIG. 10 is a development view of another embodiment of the stent of the present invention. FIG. 11 is a development view of the stent in a state where the diameter of the stent shown in FIG. 10 is reduced.
The difference between the stent 30 and the above-described stent 1 is a marker provided at both ends and a connecting portion provided in a wavy body located at both ends. The basic configuration of the stent 30 is the same as that of the stent 1 described above, and differences will be mainly described.
In this stent 30, the number of one end side bent portions and the other end side bent portions in one annular body 2 is 8, and 11 annular bodies are arranged in the axial direction. They are integrated by two adjacent annular bodies 2, two shared linear portions 21 (first pattern shared linear portions) or two shared linear portions 41 (second pattern shared linear portions). The two shared linear portions 21 are provided at positions facing the central axis of the stent. Similarly, the two shared linear portions 41 are also provided at positions facing each other with respect to the central axis of the stent.
In this stent 30, the first pattern shared linear portion 21 and the second pattern shared linear portion 41 are arranged so as to alternate with respect to the axial direction of the stent, and the first pattern shared linear portion 21 and the 2nd pattern shared linear part 41 are arrange | positioned so that it may not continue in an axial direction. Specifically, the second pattern shared linear portion 41 is arranged at a position shifted in the outer peripheral direction of the stent with respect to the arrangement position of the first pattern shared linear portion 21.

In this stent 30, as shown in FIGS. 10 and 11, a contrast marker 11 is provided. The contrast marker 11 is preferably provided at the end of the stent. In particular, it is preferable to provide both ends. Specifically, as shown in FIGS. 10 and 11, it is preferable to provide a plurality of markers 11 at both ends. The stent 30 of this embodiment has an opening 27 formed at the apex located at the end of the stent, and the marker 11 is fixed so as to close the opening 27.
As a marker, for example, a disk-shaped member of an X-ray contrast medium having a portion slightly smaller and larger than this small opening is placed in a small opening formed in the stent and pressed from both sides to form a rivet shape. It is preferable that it is attached by crimping.
The contrast marker may be any one such as for X-ray contrast and ultrasonic contrast. The marker is formed of a contrast material such as an X-ray contrast material or an ultrasound contrast material. As the marker forming material, for example, gold, platinum, tungsten, tantalum, iridium, palladium, or an alloy thereof, gold-palladium alloy, platinum-iridium, NiTiPd, NiTiAu, or the like is preferable.
And the outer side edge of the opening part 27 is the same position as the outer side edge of the other vertex part located in the edge part of a stent, as shown in FIG.10 and FIG.11. That is, in this stent 30, the outer end of the opening 27 where the marker is provided does not protrude from the outer end of the other apex portion located at the end of the stent. By aligning the end portions of the stent, the stent can be reliably pushed out even when the stent is bent.
In addition, the stent has two legs that extend from the marker placement site toward the center of the stent and are spaced apart. As shown in FIG. 11, in the contracted state (when mounted), these two legs are substantially parallel to the linear portions that are separated and close to each other.

Specifically, in this stent 30, the two leg portions extending from the opening portion 27 in the bent portion having the opening portion 27 in which the marker is disposed are inner portions of the stent of the opening portion 27 and separated by a predetermined distance. The two positions start from the inner end of the stent. For this reason, the shape near the marker forming portion (opening 27) is stabilized. Then, the vicinity of the start end portions of the two leg portions extending from the opening 27 is separated. Thus, by separating the two legs extending from the opening 27, the shape in the vicinity of the marker forming portion (opening 27) becomes more stable. For this reason, even if a strong force (during stent extrusion) is applied near the marker forming portion (opening 27), the stent is not deformed. For this reason, a stent can be extruded reliably.
In particular, in this stent 30, the two leg portions extending from the opening portion 27 in the bent portion having the opening portion 27 extend inward in the axial direction of the stent starting from two positions separated by a predetermined distance in the opening portion 27. It has become. And this stent 30 has the three opening parts 27 in the both ends of the stent, The edge part of the two leg parts extended from the two opening parts 27 of them is spaced apart. Further, the end portions of the leg portions extending from the remaining one opening portion are close to each other.

Furthermore, in this stent 30, as shown in FIGS. 10 and 11, the wavy annular body 2 located at both ends has a connecting portion 81 that connects the wavy annular body 2 and the adjacent wavy annular body 2. Is provided. In the stent 30, two connecting portions 81 are provided between the wavy annular body 2 located at both ends and the adjacent wavy annular body 2. In addition, in the stent 30, the connection part 81 is provided only between two wavy-line annular bodies located in both ends. The two connecting portions 81 are provided at positions facing each other with respect to the central axis of the stent.
As shown in FIGS. 10 and 11, at one end (upper end) of the stent 30, the two shared linear portions 21 and the above-described two connecting portions 81 are approximately the center axis of the stent. It arrange | positions so that it may become equiangular. Similarly, at the other end portion (lower end portion) of the stent 30, the two shared linear portions 41 and the two connecting portions 81 described above are substantially equiangular with respect to the central axis of the stent. Has been placed.
As described above, since the stent 30 has the connecting portions together with the shared linear portions at both ends of the stent, the shape stability of both ends after the expansion of the stent is good. In addition, in the stent 30 of the Example mentioned above, although it has two connection parts in the both ends of a stent, it is not limited to this, One or three may be sufficient.
Since the stent 30 of this embodiment is different in structure from the stent 1 described above, the resistance to the axial expansion and contraction is small, and the followability to the deformation of the blood vessel is good.

Moreover, as a stent, the stent 40 of a pattern as shown in FIG. 12 and FIG. 13 may be sufficient. FIG. 12 is a development view of another embodiment of the stent of the present invention. FIG. 13 is a development view of the stent in a state where the diameter of the stent shown in FIG. 12 is reduced.
The difference between the stent 40 and the stent 1 described above is the number of shared linear portions that integrate adjacent annular bodies, the arrangement and orientation of the shared linear portions, the markers provided at both ends, and the like.
The basic configuration of the stent 40 and the above-described stent 1 is the same.
In this stent 40, the number of one-end-side bent portions and other-end-side bent portions in one annular body 2 is the same as the stent 1 (specifically, 8 each), and 21 in the axial direction. The annular body is arranged. In the stent 40, the two adjacent annular bodies 2, the shared linear portion 51 (first pattern shared linear portion) or the shared linear portion 52 (second pattern shared linear portion) are integrated. In the stent 40, two adjacent annular bodies 2 are integrated by at least two shared linear portions. The two shared linear portions 51 are provided at positions facing each other with respect to the central axis of the stent. Similarly, the two shared linear portions 52 are also provided at positions facing each other with respect to the central axis of the stent.

In this stent 40, as shown in FIGS. 12 and 13, the wavy annular body 2 located at both ends and the adjacent wavy annular body 2 are integrated by four shared linear portions. And in the one end part (upper end part) of the stent 40, the four shared linear parts 51 mentioned above are arrange | positioned so that it may become a substantially equal angle with respect to the center axis | shaft of a stent. Similarly, at the other end portion (lower end portion) of the stent 40, the above-described four shared linear portions 52 are disposed so as to be substantially equiangular with respect to the central axis of the stent.
Thus, since the stent 40 has more shared linear portions than the other portions only at both ends of the stent, the shape stability of both ends after the expansion of the stent is good.
And in this stent 40, the 1st pattern shared line part 51 and the 2nd pattern shared line part 52 are arrange | positioned so that it may become alternate with respect to the axial direction of a stent, and 1st pattern shared line The portion 51 and the second pattern sharing linear portion 52 are arranged so as not to be continuous in the axial direction. Specifically, the second pattern shared linear portion 52 is arranged at a position shifted in the outer peripheral direction of the stent with respect to the arrangement position of the first pattern shared linear portion 51.

Further, in the stent 40, the first pattern shared linear portion 51 and the second pattern shared linear portion 52 extend obliquely with respect to the axial direction of the stent, and both have different directions.
Further, in the stent 40, the second pattern shared linear portion 52 adjacent to the first pattern shared linear portion 51 in the axial direction of the first pattern shared linear portion 51 except for both ends of the stent 40 is one end-side bent portion. And the other end side bent portion is provided at a shifted position. Then, the two first pattern shared linear portions 51 and the two second pattern shared linear portions 52 adjacent to each other in the axial direction of the stent are arranged at substantially equal angles with respect to the central axis of the stent 40. ing. For this reason, the stent can express a substantially uniform expansion force as a whole.
Further, in this stent 40, as shown in FIG. 12, the first pattern shared linear portion 51 is arranged so as to be spiral with respect to the axial direction of the stent. The 2nd pattern shared linear part 52 is also arrange | positioned so that it may become spiral shape with respect to the axial direction of a stent.

In addition, the stent 40 includes 21 wavy annular bodies arranged in the axial direction of the stent, as shown in FIG. The first pattern shared linear portion 51 is arranged so as to be spiral with respect to the axial direction of the stent. Similarly, the second pattern shared linear portion 52 is also formed of the stent. It is arranged so as to be spiral with respect to the axial direction. Specifically, every other wavy line-shaped annular body adjacent to each other is connected by two first pattern shared linear portions 51, and each first pattern shared linear portion 51 is in the axial direction of the stent. It arrange | positions so that it may become a spiral shape. For this reason, two spirals are formed by the first pattern sharing linear portion 51. Similarly, every other wavy line-shaped annular body (not connected by the first pattern sharing linear part 51) is connected by two second pattern sharing linear parts 52, The 2nd pattern shared linear part 52 is arrange | positioned so that it may become a spiral in the axial direction of a stent. For this reason, two spirals are formed by the second pattern sharing linear portion 52.
In addition, as described above, the first pattern shared linear portion 51 and the second pattern shared linear portion 52 extend obliquely with respect to the axial direction of the stent, and both have different directions. It is preferable that the directions of both are substantially symmetric with respect to the central axis of the stent. By doing so, the stent can develop a substantially uniform expansion force as a whole.

In addition, in the stent 40 of this Example, as shown in FIG. 12, the wavy line-shaped annular body 2 is a short line-shaped portion that connects between the terminal end 51b of the first pattern shared linear portion 51 and the apex 2a of the one end side bent portion. 26. And the wavy line-shaped annular body adjacent to this wavy-shaped ring-shaped body includes a short line-shaped portion 25 connecting the start end 22 of the first pattern shared line-shaped portion 51 and the apex 2b of the other end side bent portion, and the second pattern sharing The linear part 52 has a linear part that connects the end 52b and the apex of the bent part on one end side.
In this stent 40, as shown in FIGS. 12 and 13, a contrast marker 11 is provided. The contrast marker 11 is preferably provided at the end of the stent. In particular, it is preferable to provide both ends. Specifically, as shown in FIGS. 12 and 13, it is preferable to provide a plurality of markers 11 at both ends. The stent 40 of this embodiment has an opening 27 formed at the apex located at the end of the stent, and the marker 11 is fixed so as to close the opening 27. The contrast marker is the same as that described in the stent 30.

And the outer side edge of the opening part 27 is the same position as the outer side edge of the other vertex part located in the edge part of the stent 40, as shown in FIG.12 and FIG.13. That is, in this stent 40, the outer end of the opening 27 where the marker is provided does not protrude from the outer end of the other apex portion located at the end of the stent. By aligning the end portions of the stent, the stent can be reliably pushed out even when the stent is bent.
Further, in this stent 40, the two leg portions extending from the opening portion 27 in the bent portion having the opening portion 27 extend in the axially inward direction of the stent, starting from two positions separated by a predetermined distance in the opening portion 27. It has become a thing. For this reason, the shape near the marker forming portion (opening 27) is stabilized. And in this stent 40, it has the three opening parts 27 at the both ends of the stent, The edge part of the two leg parts extended from one opening part 27 of them is spaced apart. Further, the end portions of the leg portions extending from the other two openings 27 are close to each other.

In this stent 40, as shown in FIG. 12, the wavy annular body 2 located at one end of the stent and the wavy annular body 2 adjacent to the axial base end side share one end of the wavy annular body 2. A bent linear part (first pattern) located at the start end 51a of the linear part (first pattern shared linear part) 51 and the other end located at the terminal end 51b of the other shared linear part 51 in the same wavy annular body (Bent linear portion) 53 is provided. A plurality of the bent linear portions 53 are arranged in the outer peripheral direction of the stent. In particular, this stent 40 has four shared linear portions 51 at one end of the stent, and correspondingly, the wavy annular body 2 positioned at one end of the stent and the axial proximal end side. The wavy line-shaped annular body 2 adjacent to each other has four bent line-shaped portions 53. The four bent linear portions 53 are arranged so as to be substantially equiangular with respect to the central axis of the stent.
Further, in this stent 40, as shown in FIG. 12, the end 51b of the shared linear portion 51 of the wavy annular body 2 at one end and the shared linear shape of the wavy annular body 2 adjacent to the wavy annular body 2 at one end. A linear portion 57 (specifically, a short connection portion) that directly connects the end 52b of the portion 52 (adjacent to the shared linear portion) is provided. Therefore, the wavy annular body at the one end (first wavy annular body) and the third wavy annular body (the third wavy annular body) from the one end are connected by the linear portion 57 described above. ing. Also, the wavy annular body at the one end (first wavy annular body) and the third wavy annular body from the one end (third wavy annular body) are the second wavy annular body from the one end (second wavy annular body). Ring-shaped body) and the shared linear portion. Therefore, the stent 40 has a high expansion holding force at one end.
Similarly, in this stent 40, as shown in FIG. 12, the end 52b of the shared linear portion 52 of the other end of the wavy line 2 and the wavy line 2 adjacent to the other end of the wavy line 2 are connected. A linear portion 58 (specifically, a short connection portion) that directly connects the terminal end 51b of the shared linear portion 51 (adjacent to the shared linear portion) is provided. For this reason, the wavy annular body at the other end (the other end-side first wavy annular body) and the third wavy-shaped annular body (the other end-side third wavy annular body) from the other end are the above-described linear portions. 58 is connected. In addition, the wavy annular body at the other end (first wavy annular body at the other end) and the third wavy annular body at the other end (third wavy annular body at the other end) are second from the other end. It is connected to the wavy annular body (the second wavy annular body on the other end side) by the shared linear portion. Therefore, the stent 40 has a high expansion holding force at the other end.
Then, the wavy-line annular body 2 adjacent to the wavy-line annular body 2 having the bent linear-shaped portion 53 and the axially proximal end side thereof has one end shared line-shaped portion (second pattern shared line) of the wavy-line annular body 2. A bent linear portion 54 (second pattern bent linear portion) which is located at the terminal end 52b of the linear portion 52) and whose other end is located at the start end 52a of the other shared linear portion 52 in the same wavy annular body. Yes. A plurality of the bent linear portions 54 are arranged in the outer peripheral direction of the stent. In particular, the stent 40 has two shared linear portions 52 between adjacent wavy annular bodies, and correspondingly, the wavy annular body 2 having the bent linear portions 53 and The wavy line-shaped annular body 2 adjacent to the axial base end side includes two bent line-shaped portions 54. The two bent linear portions 54 are arranged so as to be substantially opposite to the central axis of the stent.

Then, the wavy-line annular body 2 adjacent to the wavy-line annular body 2 having the bent linear-shaped portion 54 and the axially proximal end side thereof has one end shared line-shaped portion (first pattern shared line) of the wavy-line annular body 2. A bent linear portion 55 (third pattern bent linear portion) located at the start end 51a of the linear portion 51) and the other end positioned at the end 51b of the other shared linear portion 51 in the same wavy annular body. Yes. A plurality of the bent linear portions 55 are arranged in the outer peripheral direction of the stent. In particular, the stent 40 has two shared linear portions 51 between adjacent wavy annular bodies, and correspondingly, the wavy annular body 2 having the bent linear portions 54 and The wavy-line annular body 2 adjacent to the axial base end side includes two bent linear portions 55. The two bent linear portions 53 are arranged so as to be substantially opposed to the central axis of the stent.
The wavy annular body 2 having the bent linear portion 55 and the wavy annular body 2 adjacent to the proximal end in the axial direction have the two bent linear portions 54 described above. The process is repeated up to one wavy annular body on the tip side of the end wavy annular body.
The wavy annular body 2 located at the proximal end of the stent 40 has four shared linear portions (second pattern shared linear shapes) between the wavy annular bodies on the distal end side of the proximal wavy annular body. Part 52), and one end is located at the end 52b of the shared line-shaped part (second pattern shared line-shaped part) 52 of the wavy line-shaped annular body 2 on the one end side of the wavy-shaped annular body at the base end, The other end is provided with a bent linear portion (fourth pattern bent linear portion) 56 located at the start end 52a of another shared linear portion 52 in the same wavy annular body. A plurality of the bent linear portions 56 are arranged in the outer peripheral direction of the stent. In particular, in the stent 40, the proximal end portion of the stent has the four shared linear portions 52 as described above, and is provided with the four bent linear portions 56 corresponding thereto. . The four bent linear portions 56 are arranged so as to be substantially equiangular with respect to the central axis of the stent.

  The stent of the present invention varies depending on the indwelling site, but generally has an outer diameter of 2.0 to 30 mm, preferably 2.5 to 20 mm, when expanded (non-reduced diameter, restored) The thickness (thickness of the linear portion) is 180 to 230 μm, preferably 190 to 210 μm, and the length is 10 to 150 mm, more preferably 15 to 100 mm. In particular, in the case of an intravascular placement stent, the outer diameter is 2.0 to 14 mm, preferably 2.5 to 12 mm, and the wall thickness (the thickness of the linear portion) is 180 to 230 μm. It is 190-210 micrometers, and length is 5-100 mm, More preferably, it is 10-80 mm.

  And the outer side edge of the opening part 27 is the same position as the outer side edge of the other vertex part located in the edge part of a stent, as shown in FIG.12 and FIG.13. That is, in this stent 40, the outer end of the opening 27 where the marker is provided does not protrude from the outer end of the other apex portion located at the end of the stent. By aligning the end portions of the stent, the stent can be reliably pushed out even when the stent is bent.

In this stent 40, as shown in FIG. 12, the wavy annular body 2 located at one end of the stent and the wavy annular body 2 adjacent to the axial base end side share one end of the wavy annular body 2. A bent linear part (first pattern) located at the start end 51a of the linear part (first pattern shared linear part) 51 and the other end located at the terminal end 51b of the other shared linear part 51 in the same wavy annular body (Bent linear portion) 53 is provided. A plurality of the bent linear portions 53 are arranged in the outer peripheral direction of the stent. In particular, this stent 40 has four shared linear portions 51 at one end of the stent, and correspondingly, the wavy annular body 2 positioned at one end of the stent and the axial proximal end side. The wavy line-shaped annular body 2 adjacent to each other has four bent line-shaped portions 53. The four bent linear portions 53 are arranged so as to be substantially equiangular with respect to the central axis of the stent.
Then, the wavy-line annular body 2 adjacent to the wavy-line annular body 2 having the bent linear-shaped portion 53 and the axially proximal end side thereof has one end shared line-shaped portion (second pattern shared line) of the wavy-line annular body 2. Bend line portion 54 (second pattern bend linear portion) located at the end 52b of the common wire portion 52 at the other end of the same wavy annular body. ing. A plurality of the bent linear portions 54 are arranged in the outer peripheral direction of the stent. In particular, the stent 40 has two shared linear portions 52 between adjacent wavy annular bodies, and correspondingly, the wavy annular body 2 having the bent linear portions 53 and The wavy line-shaped annular body 2 adjacent to the axial base end side includes two bent line-shaped portions 54. The two bent linear portions 54 are arranged so as to be substantially opposite to the central axis of the stent.

  Then, the wavy-line annular body 2 adjacent to the wavy-line annular body 2 having the bent linear-shaped portion 54 and the axially proximal end side thereof has one end shared line-shaped portion (first pattern shared line) of the wavy-line annular body 2. A bent linear portion 55 (third pattern bent linear portion) located at the start end 51a of the linear portion 51) and the other end positioned at the end 51b of the other shared linear portion 51 in the same wavy annular body. Yes. A plurality of the bent linear portions 55 are arranged in the outer peripheral direction of the stent. In particular, the stent 40 has two shared linear portions 51 between adjacent wavy annular bodies, and correspondingly, the wavy annular body 2 having the bent linear portions 54 and The wavy-line annular body 2 adjacent to the axial base end side includes two bent linear portions 55. The two bent linear portions 53 are arranged so as to be substantially opposed to the central axis of the stent.

The wavy annular body 2 having the bent linear portion 55 and the wavy annular body 2 adjacent to the proximal end in the axial direction have the two bent linear portions 54 described above. The process is repeated up to one wavy annular body on the tip side of the end wavy annular body.
The wavy annular body 2 located at the proximal end of the stent 40 has four shared linear portions (second pattern shared linear shapes) between the wavy annular bodies on the distal end side of the proximal wavy annular body. Part 52), and one end is located at the end 52b of the shared line-shaped part (second pattern shared line-shaped part) 52 of the wavy line-shaped annular body 2 on the one end side of the wavy-shaped annular body at the base end, The other end is provided with a bent linear portion (fourth pattern bent linear portion) 56 located at the start end 52a of another shared linear portion 52 in the same wavy annular body. A plurality of the bent linear portions 56 are arranged in the outer peripheral direction of the stent. In particular, in the stent 40, the proximal end portion of the stent has the four shared linear portions 52 as described above, and is provided with the four bent linear portions 56 corresponding thereto. . The four bent linear portions 56 are arranged so as to be substantially equiangular with respect to the central axis of the stent.

  The stent of the present invention varies depending on the indwelling site, but generally has an outer diameter of 2.0 to 30 mm, preferably 2.5 to 20 mm, when expanded (non-reduced diameter, restored) The thickness is 0.04 to 1.0 mm, preferably 0.06 to 0.5 mm, and the length is 10 to 150 mm, more preferably 15 to 100 mm. In particular, in the case of an intravascular placement stent, the outer diameter is 2.0 to 14 mm, preferably 2.5 to 12 mm, and the wall thickness is 0.04 to 0.3 mm, preferably 0.06 to 0.22 mm. The length is 5 to 100 mm, more preferably 10 to 80 mm.

The stents of all the embodiments described above are formed in a substantially cylindrical shape and integrally by removing portions other than the linear portions constituting the stent from the metal pipe capable of imparting superelastic characteristics.
A so-called superelastic alloy is preferably used as the metal capable of imparting superelastic characteristics. Particularly preferably, a TiNi alloy of 49 to 54 atomic% Ni, a Cu—Zn alloy of 38.5 to 41.5 wt% Zn, and a Cu—Zn—X alloy of 1 to 10 wt% X (X = Be, Si, Sn, Al, Ga), a super elastic metal body such as a 36-38 atomic% Al Ni-Al alloy is preferably used. The TiNi alloy is particularly preferable. Further, a Ti—Ni—X alloy (X = Co, Fe, Mn, Cr, V, Al, Nb, W, B, Au, in which a part of the Ti—Ni alloy is substituted with 0.01 to 10.0% X. , Pd, etc.), or a Ti—Ni—X alloy (X = Cu, Pb, Zr) in which a part of the Ti—Ni alloy is substituted with 0.01 to 30.0% atoms, By selecting the cold working rate or / and the final heat treatment conditions, the mechanical properties can be appropriately changed.

Further, the mechanical characteristics can be appropriately changed by selecting the cold work rate and / or the final heat treatment conditions using the Ti—Ni—X alloy. The buckling strength of the superelastic alloy used (yield stress under load when the superelastic characteristics are expressed) is 5 to 200 kgf / mm ² (22 ° C.), more preferably 8 to 150 kgf / mm ² . The stress (yield stress during unloading) is 3 to 180 kgf / mm ² (22 ° C.), more preferably 5 to 130 kgf / mm ² . Superelasticity here means that even if it is deformed (bending, pulling, compressing) to the region where ordinary metal plastically deforms at the operating temperature, it will recover to its original shape without requiring heating after releasing the load. Means that.
And a stent is produced by removing (for example, cutting, melt | dissolving) a stent non-component part using said metal pipe which can give a superelastic characteristic, Thereby, it is an integral formation. The superelastic metal pipe used for forming the stent of the present invention is melted in an inert gas or vacuum atmosphere to form a superelastic alloy ingot such as a Ti-Ni alloy, and this ingot is mechanically polished. Subsequently, a thick pipe is formed by hot pressing and extrusion, and then a die drawing process and a heat treatment process are sequentially repeated to reduce the diameter of the pipe to a predetermined wall thickness and outer diameter, and finally the surface. It can be produced by chemical or physical polishing. And formation of the stent base material by this superelastic metal pipe can be performed by cutting (for example, mechanical polishing, laser cutting), electric discharge machining, chemical etching, or the like, and may be performed by using them together.
Then, by appropriately performing a heat treatment on the stent formed as described above, the stent exhibits superelastic characteristics both before and after insertion into the living body. Moreover, each line | wire width of the linear part of the stent formed is 100-170 micrometers. The line width is preferably 100 to 140 μm. Further, the thickness of the linear portion (in other words, the thickness of the metal pipe) is 180 to 230 μm. The thickness of the linear portion (in other words, the thickness of the metal pipe) is preferably 190 to 210 μm.
In all the embodiments described above, the stent has a compressive load of 10 to 20 gf for compressing the axial length of the stent by 20%. In other words, the stent of the present invention can compress the stent 20% in the axial direction by a compressive load of 10 to 20 gf. And it is preferable that the stent of this invention can compress a stent 20% to an axial direction by the compressive load of 12-18gf. Furthermore, the stent of the present invention is preferably capable of compressing the stent by 20% or more in the axial direction by a compressive load of 12 to 14 gf.

  In addition, the stent of the present invention may be coated with a biocompatible material on the inner surface or outer surface, and further on both surfaces. The biocompatible material may be a synthetic resin or metal having biocompatibility. Methods for coating the stent surface with an inert metal include gold plating using electroplating, stainless steel plating using vapor deposition, silicon carbide using sputtering, diamond-like carbon, titanium nitride plating, and gold plating. Conceivable. The synthetic resin can be selected from thermoplastic or thermosetting resins. For example, polyolefin (for example, polyethylene, polypropylene, ethylene-propylene copolymer, etc.), polyvinyl chloride, ethylene-vinyl acetate copolymer. Polymers, polyamide elastomers, polyurethanes, polyesters, fluororesins, silicone resins, etc. can be used, preferably polyolefins, polyamide elastomers, polyesters or polyurethanes, silicone resins, and biodegradable resins (for example, polylactic acid, polyglycolic acid) , A copolymer of both). The synthetic resin coating is preferably flexible to the extent that it does not hinder the bending of the frame constituting the stent. The thickness of the synthetic resin coating is 3 to 300 μm, preferably 5 to 100 μm.

As a method of thinly coating the surface of the stent with a synthetic resin, for example, a method in which a stent is inserted into a synthetic resin in a molten state or a solution state, and coating is performed while a monomer is polymerized on the surface of a superelastic metal pipe. Chemical vapor deposition. When an extremely thin resin coating is required, coating using a dilute solution or chemical vapor deposition is preferable. Furthermore, in order to improve the biocompatible material, an antithrombotic material may be coated or fixed on the resin coating. As the antithrombogenic material, various known resins can be used alone or in combination. For example, polyhydroxyethyl methacrylate, a copolymer of hydroxyethyl methacrylate and styrene (for example, HEMA-St-HEMA) Block copolymers) can be used preferably.
In all the embodiments described above, it is preferable to provide a marker 11 as shown in FIGS. The contrast marker 11 is preferably provided on the end side of the stent. In particular, it is preferable to provide the both ends. Specifically, it is preferable to provide a plurality of markers 11 on both ends. The marker is as described above.

Next, specific examples of the stent of the present invention will be described.
(Example 1)
A TiNi alloy (51 atomic% Ni) alloy pipe was cold worked to produce a metal pipe having an outer diameter of about 1.9 mm, a wall thickness of 0.25 mm, and a length of about 100 mm. Then, the metal pipe was set in a jig with a rotary motor with a fastener mechanism so as not to shake the shaft, and further set on an X table capable of numerical control. The X table and the rotary motor were connected to a personal computer, and the output of the personal computer was input to the numerical control controller and the rotary motor of the X table. Drawing software is stored in the personal computer, and a developed drawing of the stent having the composition as shown in FIG. 2 is input here. With such a configuration, the X table and the rotary motor are driven based on the drawing data output from the personal computer.
By irradiating the metal pipe with the laser in this manner, a stent base material having a developed view as shown in FIG. 2 was produced.
The laser processing conditions for the metal pipe were an average output of 5.5 W and a driving speed of 180 mm / min. And the inner surface grinding process was performed to said stent base material.

Next, the diameter of the stent substrate is expanded by inserting a core metal having a diameter slightly larger than that of the stent substrate lumen into the stent substrate lumen, and the stent substrate is heat treated while the core metal is inserted to expand the diameter. The shape was memorized. By this diameter expansion heat treatment step, the stent base material is formed into a shape slightly thicker than the original diameter (original diameter is around +1 mm). For example, a metal such as stainless steel is suitable for the material of the metal core, and the heat treatment temperature is preferably 450 ° C. to 550 ° C., and the time is preferably about 2 minutes to 30 minutes. Subsequently, a slightly thicker core (diameter after diameter expansion + around 2 mm) is inserted into the stent substrate lumen to expand the diameter, and heat treatment is performed. Thus, the stent base material as shown in FIG. 1 is produced by repeating the diameter expansion heat treatment until the stent base material reaches the target outer diameter. In addition, you may perform a chemical polishing process as needed whenever it passes through one heat processing process.
The stent base material molded into the target shape was appropriately subjected to a blasting process, a chemical polishing process, and an electrolytic polishing process, followed by a process of smoothing the surface and imparting a metallic luster.
The stent thus produced has an outer diameter of about 8 mm, a total length of about 45 mm, a wall thickness of about 200 μm, a line width of the linear portion of each annular body of about 113 μm, an axial length of the annular body of about 3 mm, and a shared linear shape. The length of the part was about 1.6 mm.
This stent has a sufficient expansion force and is less likely to cause strain concentration at the connection portion.

(Example 2)
A stent base material as shown in FIG. 4 was produced in the same manner as in Example 1 except that the development drawing of the stent having the composition as shown in FIG. 5 was input to the personal computer. The stent base material molded in the same manner as in Example 1 was appropriately subjected to a blasting process, a chemical polishing process, and an electrolytic polishing process to smooth the surface and impart a metallic luster.
The stent thus produced has an outer diameter of about 8 mm, a total length of about 45 mm, a wall thickness of about 200 μm, a line width of the linear portion of each annular body of about 113 μm, an annular body axial length of about 3 mm, and a shared linear shape. The length of the part was about 1.6 mm.
This stent has a sufficient expansion force and is less likely to cause strain concentration at the connection portion.

(Example 3)
A stent base material as shown in FIG. 7 was produced in the same manner as in Example 1 except that the development drawing of the stent having the composition as shown in FIG. 8 was input to the personal computer. The stent base material molded in the same manner as in Example 1 was appropriately subjected to a blasting process, a chemical polishing process, and an electrolytic polishing process to smooth the surface and impart a metallic luster.
The stent thus produced has an outer diameter of about 8 mm, a total length of about 45 mm, a wall thickness of about 200 μm, a line width of the linear portion of each annular body of about 113 μm, an axial length of the annular body of about 3 mm, and a shared linear shape. The length of the part was about 1.6 mm.
This stent has a sufficient expansion force and is less likely to cause strain concentration at the connection portion.

Example 4
A stent base material was produced in the same manner as in Example 1 except that the development drawing of the stent having the composition as shown in FIG. 10 was input to the personal computer. The stent base material molded in the same manner as in Example 1 was appropriately subjected to a blasting process, a chemical polishing process, and an electrolytic polishing process to smooth the surface and impart a metallic luster.
The stent thus produced has an outer diameter of about 8 mm, a total length of about 45 mm, a wall thickness of about 200 μm, a line width of the linear portion of each annular body of about 113 μm, an axial length of the annular body of about 3 mm, and a shared linear shape. The length of the part was about 1.4 mm.
This stent has a sufficient expansion force and is less likely to cause strain concentration at the connection portion.

(Example 5)
A stent base material was produced in the same manner as in Example 1 except that the development drawing of the stent having the composition as shown in FIG. 12 was input to the personal computer. The stent base material molded in the same manner as in Example 1 was appropriately subjected to a blasting process, a chemical polishing process, and an electrolytic polishing process to smooth the surface and impart a metallic luster.
The stent thus produced has an outer diameter of about 8 mm, a total length of about 45 mm, a wall thickness of about 200 μm, a line width of the linear portion of each annular body of about 113 μm, an axial length of the annular body of about 3 mm, and a shared linear shape. The length of the part was about 1.4 mm.
This stent has a sufficient expansion force and is less likely to cause strain concentration at the connection portion.

(Comparative example)
A stent substrate was produced in the same manner as in Example 1 except that the development drawing of the stent 60 having the composition as shown in FIG. 14 was input to the personal computer. The stent base material molded in the same manner as in Example 1 was appropriately subjected to a blasting process, a chemical polishing process, and an electrolytic polishing process to smooth the surface and impart a metallic luster.
The stent thus produced has an outer diameter of about 8 mm, an overall length of about 45 mm, a thickness of about 200 μm, a line width of each linear body 62 of about 113 μm, an annular body 62 having an axial length of 2 mm, and a connecting portion. The length of 63 was about 0.2 mm.
This stent has a sufficient expansion force and is less likely to cause strain concentration at the connection portion.

(Experiment)
Stents are implanted in various parts of a body lumen, but the required functions differ depending on the location. For example, in the case of the carotid artery, renal artery, etc., it is preferable that the stent has a relatively strong resistance against the axial extension and compression of the stent. The reason is that these blood vessels are less stretched and contracted by the movement of the living body, the stent is less stretched and contracted, and the type that holds the blood vessels firmly is better. In addition, since the iliac artery is a place where the expansion and contraction of the blood vessel due to the movement of the living body is relatively small and the diameter of the blood vessel is relatively large, the type that firmly holds the blood vessel is also preferable. Also, when the blood vessel is calcified and hard, radial force (radial compression resistance) is required, and in the experimental measurement results described later, a stent with a higher radial compression load maintains and expands the blood vessel diameter. It is preferable to be able to.
On the other hand, in the superficial femoral artery and the popliteal artery, the blood vessel greatly expands and contracts due to the movement of the living body, and in many cases the lesion is long, so a long stent needs to be implanted. As a required stent function, it is preferable that the stent is relatively resistant to the axial expansion and contraction of the stent and is flexible in the axial direction. Therefore, as a result of intensive research, we have developed stents with different resistance (flexibility) to axial expansion and contraction even though they have almost the same stent structure.
About the Example and the comparative example, the compressive load (axial compressive load) for compressing 20% of axial length was measured. Specifically, gripping both ends of each stent having an outer diameter of 8 mm and a length of 45 mm, taking an effective length of the stent of 20 mm, compressing in 37 ° C. water at a compression speed of 5 mm / min, and an effective stent length of 16 mm The force at the time of becoming was measured. The results were as shown in Table 1.
About the Example and the comparative example, the radial direction compressive load was measured. Specifically, each stent was placed between two flat plates in water, the flat plate was pressed, and the force when the outer diameter of the stent became 4 mm was measured. The results were as shown in Table 1.

(Table 1)
┌─────┬─────────────┬─────────────┐
│Stent │ Axial compressive load (gf) │ Radial compressive load (gf) │
├─────┼─────────────┼─────────────┤
│Example 1 │ 11.5 │ 70.0 │
├─────┼─────────────┼─────────────┤
│Example 2 │ 18.3 │ 50.5 │
├─────┼─────────────┼─────────────┤
│Example 3 │ 17.3 │ 53.6 │
├─────┼─────────────┼─────────────┤
│Example 4 │ 17.2 │ 63.6 │
├─────┼─────────────┼─────────────┤
│Example 5 │ 13.0 │ 72.5 │
├─────┼─────────────┼─────────────┤
│Comparison example │ 124.1 │ 75.0 │
└─────┴─────────────┴─────────────┘

FIG. 1 is a front view of a stent according to an embodiment of the present invention. FIG. 2 is a development view of the stent shown in FIG. FIG. 3 is a development view of the stent in a state where the diameter of the stent shown in FIG. 1 is reduced. FIG. 4 is a front view of a stent according to another embodiment of the present invention. FIG. 5 is a development view of the stent shown in FIG. 4. FIG. 6 is a development view of the stent in a state where the diameter of the stent shown in FIG. 4 is reduced. FIG. 7 is a front view of a stent according to another embodiment of the present invention. FIG. 8 is a development view of the stent shown in FIG. FIG. 9 is a development view of the stent in a state where the diameter of the stent shown in FIG. 7 is reduced. FIG. 10 is a developed view of a stent according to another embodiment of the present invention. FIG. 11 is a development view of the stent in a state where the diameter of the stent shown in FIG. 10 is reduced. FIG. 12 is a development view of a stent according to another embodiment of the present invention. FIG. 13 is a development view of the stent in a state where the diameter of the stent shown in FIG. 12 is reduced. FIG. 14 is a development view of the stent of the comparative example.

Explanation of symbols

1 Stent 2 Annular 21 Shared linear part

Claims (14)

A self-expanding in-vivo stent that is substantially cylindrical and integrally formed by removing a portion other than a linear portion constituting the stent from a metal pipe capable of imparting superelastic characteristics, In addition, it exhibits superelastic properties both before and after insertion into the living body, and each line width of the linear portion of the stent is 100 to 170 μm, and the thickness of the linear portion is 180-230 μm, and the stent is a self-expanding in-vivo stent, wherein the compressive load for compressing the axial length of the stent by 20% is 10-20 gf. The stent includes a plurality of wavy annular bodies made of the linear portions in the axial direction, and the wavy annular bodies have a plurality of one end side bent portions having apexes on one end side in the axial direction of the stent, and The wavy line-shaped annular body having a plurality of other end side bent portions having apexes on the other end side in the axial direction of the stent and adjacent to the proximal end side in the axial direction of the stent is provided on one end side in the axial direction of the stent. A shared linear portion having a starting end at or near one apex of the other end side bent portion in the wavy annular body, and having an end between the apex of the other end side bent portion and the apex of the one end side bent portion The indwelling stent according to claim 1, wherein adjacent wavy annular bodies are integrated by the shared linear portion. The in-vivo according to claim 2, wherein the stent has a start end branch portion formed by the start end portion of the shared linear portion and a terminal branch portion formed by the end portion of the shared linear portion. Indwelling stent. The stent for in-vivo indwelling of Claim 2 or 3 provided with the some shared linear part between the said adjacent wavy-line annular bodies. A plurality of shared linear portions are provided between the adjacent wavy annular bodies, and the plurality of shared linear portions are opposed to or substantially equiangular with respect to the central axis of the stent. The stent for in-vivo indwelling in any one of Claim 2 thru | or 4 currently formed in. The apex of the one end side bent portion of the wavy annular body enters a space formed between the other end side bent portions of one adjacent wavy annular body, and the other end side bent portion of the wavy annular body The in-vivo indwelling stent according to any one of claims 2 to 5, wherein the apex of is invaded into a space formed between the bent portions on one end side of the other adjacent wavy-line annular body. The stent has a first pattern sharing linear portion extending obliquely at a predetermined angle with respect to the central axis of the stent, and a direction different from the first pattern sharing linear portion obliquely with respect to the central axis of the stent and at a predetermined angle. The stent for in-vivo indwelling in any one of Claims 2 thru | or 6 provided with the 2nd pattern shared linear part extended in. The in-vivo stent according to claim 7, wherein the first pattern shared linear portion and the second pattern shared linear portion are arranged so as to be alternated with respect to an axial direction of the stent. The in-vivo indwelling according to claim 7 or 8 with which said 2nd pattern share linear part is arranged in a position shifted in the perimeter direction of a stent with respect to an arrangement position of said 1st pattern share linear part. Stent. One end of the stent is located at the start or end of the shared linear portion of the wavy annular body, and the other end of the stent is adjacent to the wavy annular body on the axial base end side. The stent for in-vivo indwelling in any one of Claims 2 thru | or 9 provided with the bending linear part which is located in the start end or terminal end of this, and has a one end side bending part or / and the other end side bending part. The in-vivo indwelling stent according to any one of claims 2 to 10, wherein the stent includes a connecting portion that connects a wavy annular body located at both ends and a neighboring wavy annular body. 12. The stent according to claim 2, wherein the shared linear portion is provided between the wavy ring-shaped bodies adjacent to the wavy-shaped ring bodies located at both ends, as compared with the wavy-shaped ring bodies of other portions. The stent for in-vivo in any one of Claims. The said stent is provided with the contrast marker provided in the edge part of this stent, The edge part of this contrast marker arrangement | positioning site | part does not protrude from the edge part of the said stent. In vivo indwelling stent. The stent includes a contrast marker provided at an end portion of the stent, and further includes two legs that extend in the center direction of the stent from the marker placement site and are in a contracted state. The indwelling stent according to any one of claims 1 to 13, wherein the two leg portions are substantially parallel to the linear portions that are separated and close to each other.

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