JP2009240614A - In vivo indwelling stent and living organ dilator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a stent that has a sufficient rigidity during the work to be inserted into a body cavity, can be inserted into even an classified in vivo region, and has excellent flexibility and dilation maintainability after dilating the region where it is inserted. <P>SOLUTION: In the stent 1, there are arranged a plurality of annular bodies 2 each having the pluralities of one-end side bent parts 4a, the other-end side bent parts 5a and clearance parts 7a, 7b. The stent has three or more regions, relative to the central axis of the stent 1, in each of which the one-end side bent part 4a of one of the two adjacent annular bodies 2 has neared the other-end side bent part 5a of the other annular body 2. The stent has an adjacent region deformation control part at minimum three adjacent regions, each including a first protrusion line part 6a entering the clearance part 7a of the other annular body spread along one side of the adjacent region from one adjacent annular body, and a second protrusion line part 6b entering the clearance part 7b of one annular body spread along the other side of the adjacent region from the other adjacent annular body. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an in-vivo indwelling stent and a biological organ dilator used to improve a stenosis or occlusion in a biological lumen such as a blood vessel, a bile duct, a trachea, an esophagus, or a urethra.

In-vivo stents are used 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. In general, it is a tubular medical device.
Since the stent is inserted into the body from outside the body, the diameter is small at that time. The stent is expanded at the target stenosis or occlusion site to increase the diameter, and the lumen is held as it is.

As the stent, a metal wire or a cylindrical shape obtained by processing a metal tube is generally used. It is attached to a catheter or the like in a thin state, inserted into a living body, expanded by a certain method at a target site, and closely adhered to and fixed to the inner wall of the lumen to maintain the lumen shape. Stents are classified into self-expandable stents and balloon expandable stents according to function and placement method. 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.
In a stenosis site where a stent is to be placed, calcification has progressed and may be quite hard, and a stent that can be inserted into such a site is desired.

  For example, Japanese Patent Publication No. 2005-501654 (Patent Document 1) discloses an expandable stent including a tubular body composed of a number of separated tubular elements (1) aligned along a common longitudinal axis. Each tubular element (1) includes a number of rhombus-shaped occlusion cell elements (2) connected by a peripherally extending connecting member (3) to expand the tubular element and hence the stent itself The closed cell element (2) is expandable so that in the longitudinal direction of the stent, there is an enlarged loop (30) with a constricted portion (33) at the tip of each closed cell element, Tubular elements are thereby disclosed in which the interlock is closed to create a stable structure, at least when in an unexpanded state.

JP 2005-501654 A

  In Patent Document 1, a number of separated tubular elements are interlocked when placed on a balloon. For this reason, when mounted on a balloon, the rigidity is high, and insertion into a calcified lesion site is possible. The stent is then stretched to release the interlock between a number of separated tubular elements. However, each tubular element can be individually deformed and the flexibility between the tubular elements is good. However, since the individual tubular elements are short and small, there is a possibility that they will move individually when the expansion force is reduced, and there is a possibility that the intended target site cannot be continuously expanded. In addition, due to the difference in partial hardness difference such as calcification of the indwelling target site, there may be partial expansion failure in the stent. In the expansion failure portion, the interlock is not released, and the stent after placement is Therefore, it is possible that undesired deformation directionality is manifested and that it may cause restenosis.

  It is an object of the present invention to have sufficient rigidity at the time of insertion into a body cavity, can be inserted into a hard in vivo site such as calcification, and has an undesired deformation direction after expansion. Therefore, the present invention provides an in-vivo indwelling stent having sufficient flexibility and expansion maintaining force, and a living organ dilator having the same.

What achieves the above object is as follows.
(1) An in-vivo indwelling stent that is in close contact with in-vivo tissue by being deformed during an in-vivo indwelling operation, wherein the stent is formed in an annular shape by linear components, and a plurality of one-end-side bent portions and A plurality of annular bodies having a plurality of other end-side bent portions and a plurality of gap portions extending between adjacent bent portions are arranged in the axial direction, and the adjacent annular bodies are connected by a connecting portion. In the stent, three adjacent portions where the one end side bent portion of one of the adjacent annular bodies and the other end side bent portion of the other annular body are close to each other are at least approximately equiangular with respect to the central axis of the stent. In addition, the stent extends from any one of the adjacent annular bodies, passes through one side of the adjacent portion, and enters the gap portion of the adjacent annular body. A second projecting linear portion and a second one that extends from one of the adjacent annular bodies, passes through the other side of the adjacent portion, and enters the gap portion of the adjacent annular body. Proximity part deformation suppression parts comprising projecting linear parts are provided in at least two of the proximate parts, and the stent has at least the gap into which the projecting linear part has entered during the indwelling operation. The in-vivo indwelling stent, wherein the protruding linear portion is separated from the linear component forming the gap portion by being deformed in the opening direction of the bent portion forming the terminal end of the portion.

(2) The in-vivo indwelling stent according to (1), wherein the proximity part deformation suppressing unit is provided in at least two adjacent parts that do not face the central axis of the stent.
(3) The stent possesses four adjacent portions at an interval of approximately 90 degrees with respect to the central axis of the stent, and includes at least two adjacent portions that do not face each other. A stent for in-vivo placement according to 1).
(4) The stent possesses three neighboring sites at an interval of approximately 120 degrees with respect to the central axis of the stent, and includes the neighboring site deformation suppressing portions at two or more neighboring sites (1) The stent for in-vivo indwelling.
(5) The in-vivo placement according to any one of (1) to (3), wherein each of the adjacent portions is located between the first protruding linear portion and the second protruding linear portion. Stent.
(6) The first protruding linear portion extends from the one adjacent annular body toward the other annular body, and the second protruding linear portion is the other adjacent annular body. The stent for in-vivo placement according to any one of the above (1) to (5), which extends in the direction of the one annular body.

(7) The above-mentioned bent portions that form the end of the gap portion into which the protruding linear portion intrudes are larger than the other bent portions when the stent is expanded (1) to (6) The stent for indwelling in any one of (4).
(8) The protruding linear portion has a starting end at or near the bent portion of one of the annular bodies and a free end that terminates in the gap portion of the other annular body ( 1) The stent for indwelling in any one of (7).
(9) The protruding linear portion has a starting end inside the bending portion located on the side of the bending portion forming the proximity portion, and a free end that terminates in the gap portion of the other annular body. The stent for in-vivo placement according to any one of (1) to (7) above.

(10) Each of the annular bodies includes a plurality of the one end side bent portions having apexes on one end side in the axial direction of the stent and a plurality of the other end side bent portions having apexes on the other end side in the axial direction of the stent. And any one of the above (1) to (9), which is an endless annular body that is continuous in an annular shape and has a plurality of connecting linear portions connecting the one end-side bent portions and the other end-side bent portions. In vivo indwelling stent.
(11) The living body according to any one of (1) to (10), wherein the one-end-side bent portion and the other-end-side bent portion in the proximity portion are located slightly shifted in the circumferential direction of the stent. Indwelling stent.
(12) The in-vivo indwelling device according to any one of (1) to (10), wherein the one-end-side bent portion and the other-end-side bent portion in the proximity portion face each other in the axial direction of the stent. Stent.

(13) The annular bodies are arranged so that linear ring portions that are long in the axial direction of the stent having the one end side bent portion and the other end side bent portion surround the central axis of the plurality of stents, and are adjacent to each other. The in vivo indwelling stent according to any one of the above (1) to (9), wherein the linear ring portion is composed of an annular body connected at a joint portion.
(14) The protruding linear portion has a starting end in the vicinity of the joint portion of one of the annular bodies and a free end that terminates in the gap portion of the other annular body. The stent for in-vivo indwelling.

  (15) The stent is formed in a substantially tubular body, has a diameter for insertion into a lumen in a living body, and expands when a force spreading in the radial direction from the inside of the stent is applied. The in-vivo stent according to any one of (1) to (14) above.

Moreover, what achieves the said objective is as follows.
(16) A tube-shaped shaft main body, a foldable and expandable balloon provided at the distal end of the shaft main body, and a foldable balloon mounted on the balloon. A living organ dilator comprising the stent according to (15), which is expanded by expansion.

  (17) The stent is formed in a substantially cylindrical shape, is compressed in the central axis direction when inserted into a living body, and expands outward when placed in the living body to restore the shape before compression. (14) The stent for in-vivo indwelling in any one of.

Moreover, what achieves the said objective is as follows.
(18) A sheath, the stent of (17) housed in the distal end portion of the sheath, and an inner tube for slidably passing through the sheath and pushing out the stent from the distal end of the sheath. Biological organ dilator.

  The in-vivo indwelling stent of the present invention includes three or more adjacent portions provided at substantially the same angle with respect to the central axis of the stent, and the at least two adjacent portions include the first protruding linear portion and the first portion. It was sandwiched between the two protruding linear parts and had sufficient rigidity because it was restrained from deforming between the annular bodies during insertion into the body cavity, and became hard like calcification It can be inserted into a body part. Then, at the time of indwelling operation in the living body, the protruding linear part is separated from the linear component forming the gap part by deforming at least the bent part that forms the terminal end of the gap part. Has sufficient flexibility and expansion maintaining power without exhibiting undesired deformation directionality.

The in-vivo indwelling stent of the present invention will be described using the following preferred embodiments.
FIG. 1 is a front view of an in-vivo stent according to an embodiment of the present invention. FIG. 2 is a development view of the in-vivo stent of FIG. FIG. 3 is a partially enlarged view of FIG. 4 is a front view of the in-vivo indwelling stent of FIG. 1 when expanded. FIG. 5 is a developed view of the in-vivo indwelling stent of FIG. 1 during expansion.

  The in-vivo indwelling stent 1 of the present invention is an in-vivo indwelling stent that is in close contact with an in-vivo tissue by being deformed during an in-vivo indwelling operation. The stent 1 is formed in an annular shape by linear components, and includes a plurality of one end side bent portions 4a and 4b, a plurality of other end side bent portions 5a and 5b, and a plurality of gap portions 7a and 7b extending between adjacent bent portions. The annular bodies 2 are arranged in a plurality of axial directions, and the adjacent annular bodies 2 are connected by a connecting portion 3. Further, the stent 1 is configured such that the adjacent portion 9 where the one end side bent portion 4a of the adjacent one annular body 2 and the other end side bent portion 5a of the other annular body 2 are close to each other is at least substantially equal to the central axis of the stent 1. There are more than 3 locations at an angle.

  Furthermore, the stent 1 extends from any one of the adjacent annular bodies 2, passes through one side of the adjacent portion 9, and enters the gap 7 a of the adjacent annular body 2. A second protruding linear shape extending from one of the annular portions of the annular portion 6a and the adjacent annular body 2, passing through the other side portion of the adjacent portion 9 and entering the gap portion 7b of the adjacent annular body 2 The proximity part deformation | transformation suppression part which consists of a part 6b is provided. And this proximity part deformation | transformation suppression part is equipped with the proximity part 9 of at least 2 places. Further, the stent 1 is deformed in the direction in which the bent portions 4a and 5a forming the terminal ends of the gap portions 7a and 7b into which the protruding linear portions 6a and 6b have entered at the time of indwelling operation in the living body. The protruding linear portions 6a and 6b are separated from the linear components forming the portions 7a and 7b.

The stent 1 of this embodiment is formed in a substantially tubular body, has a diameter for insertion into a lumen in a living body, and is expandable when a force spreading radially from the inside of the tubular body is applied. This is a so-called balloon expandable stent. The stent of the present invention is not limited to a balloon expandable stent.
As shown in FIG. 1 to FIG. 5, the stent 1 of this embodiment has a configuration in which a plurality of wavy annular bodies 2 are arranged so as to be adjacent in the axial direction and are connected to each other.
Each wavy-line annular body 2 includes a plurality of one end side bent portions 4a and 4b having apexes on one end side in the axial direction of the stent 1 and a plurality of other end sides having apexes on the other end side in the axial direction of the stent 1. It has bending portions 5a and 5b and a plurality of gap portions 7a and 7b extending between adjacent bending portions, and is constituted by an endless linear constituent element (specifically, a wavy linear body) that is annularly continuous. .

In the stent 1 of this embodiment, as shown in FIGS. 1 to 5, the annular body 2 includes a plurality of one end side bent portions 4a and 4b located on one end side of the stent and a plurality of others located on the other end side. It has a connecting line-shaped part that connects the end-side bent parts 5a and 5b. And in the stent 1 of this Example, the connection linear part is a linear part. The gap portions 7a and 7b extend in the axial direction of the stent between adjacent bent portions.
The annular body 2 adjacent in the axial direction includes the other end side bent portion 5b of the annular body 2 located on one end side of the stent and the one end side bent portion 4b of the annular body 2 located on the other end side. Connected by.
The stent 1 is inserted into the living body in the state shown in FIG. 1, and expands to the state shown in FIG. 4 when a force spreading radially from the inside of the stent is applied. In the developed view, the state of FIG. 2 is changed to the state of FIG. And at the time of said deformation | transformation, the one end side bending parts 4a and 4b and the other end side bending parts 5a and 5b deform | transform in the opening direction.

As shown in FIGS. 1 and 2 and FIG. 3 which is a partially enlarged view thereof, the corrugated annular body 2 in the stent 1 of this embodiment has a plurality of one end side bent portions 4a and 4b and other end side bent portions having substantially the same pitch. It has portions 5a and 5b and a connecting line-shaped portion, and is an endless wavy body that is continuous in an annular shape. In addition, 4-10 are suitable for the number of the peaks (or valleys) of the wavy annular body.
Further, in the annular body 2 in the stent 1, a first one end side bent portion 4 a located on one end side in each annular body 2 and a second end located slightly on the other end side from the first one end side bent portion. One end side bent portions 4b are provided, and they are arranged alternately. Similarly, in the annular body 2 in the stent 1, the first other-end-side bent portion 5 a positioned on the other end side in each annular body 2 and slightly positioned on the one-end side from the first other-end-side bent portion. The second other-end bending portion 5b is provided, and they are arranged so as to alternate.

  In the adjacent annular body, the first one-end-side bent portion 4a of the annular body 2 on the other end side and the first other-end-side bent portion 5a of the annular body 2 on the one-end side are close to each other, Forming. In this stent 1, the first one end side bent portion 4a and the first other end side bent portion 5a at the adjacent portion are not in a state of facing each other but slightly shifted in the circumferential direction of the stent. Then, as shown in FIG. 2, four adjacent portions 9 are formed at approximately 90 ° intervals with respect to the central axis of the stent 1. Note that at least three adjacent portions 9 may be possessed at substantially the same angle with respect to the central axis of the stent 1, or may be provided at five or more locations.

And between adjacent annular bodies, as shown in FIG.2 and FIG.3, it extends in the direction of an adjacent annular body from any annular body of the adjacent annular body 2, and is located in one side part of the adjacent part 9 A first protruding linear portion 6a that enters the gap portion 7a, and a gap portion that extends in the direction of the adjacent annular body from any one of the adjacent annular bodies 2 and is located on the other side of the adjacent portion 9 The proximity part deformation | transformation suppression part which consists of the 2nd protrusion linear part 6b which penetrates 7b is provided in the proximity part 9 of at least 2 places. And it is preferable that the proximity site | part deformation | transformation suppression part is provided in the 2 proximity site which does not face at least with respect to the center axis | shaft of a stent.
For example, as in the case of the stent 1 of this embodiment, in the case where four adjacent portions 9 are owned at an interval of approximately 90 degrees with respect to the central axis of the stent 1, at least two adjacent portion deformation suppressing portions are not opposed to each other. It is preferable to provide in the proximity part. Moreover, you may provide a proximity | contact part deformation | transformation suppression part in three or more places, and also all the proximity | contact parts. In addition, when the stent has three adjacent portions at intervals of approximately 120 degrees with respect to the central axis of the stent, since they do not face each other in the axial direction, the adjacent portion deformation suppressing portions are located at any two locations. What is necessary is just to provide. Moreover, it is good also as what is provided in the proximity | contact part of 2 or more places (in other words, all).

In the stent 1 of this embodiment, the first protruding linear portion 6a extends in the direction of the other annular body from the adjacent one of the annular bodies 2, and the second protruding linear portion 6b It extends in the direction of one annular body from the annular body. In the stent of this embodiment, the protruding linear portions 6a and 6b have free ends that end in the vicinity of the bent portion of one annular body 2 and terminate in the gap portions 7a and 7b of the other annular body. It has become.
Specifically, as shown in FIG. 3, the first protruding linear portion 6 a is located at the center of the stent 1 from the first other-end-side bent portion 5 a of the one-side annular body 2 that forms the proximity portion 9. Passes through the side of the first one-end-side bent portion 4a of the annular body 2 on the other end side that extends substantially parallel to the axis and forms the proximity portion, and enters the gap 7a of the annular body 2 on the other end side, Moreover, it terminates without reaching the bent portion 5a which is the end of the gap 7a. Further, the second protruding linear portion 6b extends substantially parallel to the central axis of the stent 1 from the first one-end bent portion 4a of the annular body 2 on the other end side that forms the proximity portion 9, and the proximity portion 9 Bend that passes through the side of the first other-end-side bent portion 5a of the annular body 2 on one end side, enters the gap 7b of the annular body 2 on one end-side, and serves as the end of the gap 7b The terminal ends without reaching the portion 4a. As shown in FIG. 3, the two bent portions 4a and 5a that form the adjacent portion 9 between the adjacent annular bodies are provided with protruding linear portions 6a and 6b that invade into the opposing gap portions 7a and 7b. , Nested. For this reason, the first protruding linear portion 6a that has entered the gap of the annular body 2 on the other end side suppresses deformation of the annular body 2 on the other end side, and similarly, the gap between the annular body 2 on the one end side. The deformation of the annular body 2 on one end side is suppressed by the second protruding linear portion 6b that has entered the inside.

As shown in FIG. 2, four adjacent portions 9 are formed at approximately 90 ° intervals with respect to the central axis of the stent 1, and each of the adjacent portions 9 has the first protruding linear shape described above. Proximal part deformation suppressing parts including the part 6a and the second protruding linear part 6b are provided. For this reason, the non-expanded stent 1 is hardly bent in substantially any direction and has sufficient rigidity.
And in this stent 1, the 2nd other end side bending part 5b of the annular body of the one end side mentioned above and the 2nd one end side bending part 4b of the annular body of the other end side are connected by the connection part 3. Thus, the adjacent annular bodies are connected. In the stent 1 of this embodiment, a plurality of (specifically, two) connecting portions 3 are provided between adjacent annular bodies. In particular, in the stent 1 of this embodiment, two connecting portions 3 are provided so as to be substantially opposed to the central axis of the stent. Three or more connecting portions 3 may be provided so as to be equiangular with respect to the central axis of the stent 1.

  Furthermore, in the stent 1 of this embodiment, as shown in FIG. 3, the terminal end of the gap portion 7a into which the first protruding linear portion 6a enters is located on the other end side from the second other end side bent portion 5b. It becomes the 1st other end side bending part 5a to do. Each annular body 2 is the same as the linear portion 8a that connects the first other-end-side bent portion 5a and the first one-end-side bent portion 4a located on one end side from the second one-end-side bent portion 4b. The linear part 8b which connects the 1st other end side bending part 5a and the 2nd one end side bending part 4b is provided, and the gap | interval part 7a is formed between the linear part 8a and the linear part 8b. For this reason, the linear body constituting the gap portion 7a is long, and the first other-end-side bent portion 5a that forms the end of the gap portion 7a is surely and sufficiently formed by the stress during expansion of the stent. It is something that opens.

  Similarly, the end of the gap portion 7b into which the second protruding linear portion 6b enters is a first one end side bent portion 4a located on one end side from the second one end side bent portion 4b. Each annular body 2 has a linear portion 8a that connects the first other-end-side bent portion 4a and the first other-end-side bent portion 5a located on the other end side from the second other-end-side bent portion 5b. And a linear portion 8c that connects the same first end-side bent portion 4a and the second other-end-side bent portion 5b, and a gap portion 7b is formed between the linear portion 8a and the linear portion 8c. Yes. For this reason, the linear body constituting the gap 7b is long, and as shown in FIGS. 4 and 5, the first end that forms the end of the gap 7b due to the stress during expansion of the stent. The side bent portion 4a is surely and sufficiently opened.

In other words, in the stent 1 of this embodiment, the bent portions 4a and 5a that form the ends of the gap portions 7a and 7b into which the protruding linear portions 6a and 6b invade open wider than other bent portions when the stent is expanded. It has become a thing. For this reason, when the stent 1 is expanded, the protruding linear portions 6a and 6b are surely separated from the linear components forming the gap portions 7a and 7b, and the protruding linear portions do not hinder the deformation of the annular body.
In the stent 1 described above, the protruding linear portions 6a and 6b have a starting end at the apex of the bent portions 4a and 5a. However, the protruding linear portions 6a and 6b only have to have a starting end near the bent portion or the bent portion. .
Moreover, it is preferable that the penetration | invasion length to the gap | interval parts 7a and 7b of the cyclic | annular body which the protrusion linear parts 6a and 6b adjoin is 0.2-1.5 mm.

Next, an in-vivo stent according to another embodiment of the present invention will be described.
FIG. 6 is a developed view of a stent for in vivo placement according to another embodiment of the present invention.
The basic configuration of the stent 10 of the embodiment shown in FIG. 6 and the above-described stent 1 is the same. In the stent 10 of this embodiment, the protruding linear portions 16a and 16b have start ends on the inner sides of the bent portions 14 and 15 located on the sides of the bent portions 14 and 15 forming the adjacent portion, and the other annular body. It has a free end that terminates in the gaps 17a, 17b.

As shown in FIG. 6, the stent 10 of this embodiment has a configuration in which a plurality of wavy annular bodies 12 are arranged so as to be adjacent in the axial direction and are connected to each other.
Each wavy annular body 12 includes a plurality of one end side bent portions 14 having apexes on one end side in the axial direction of the stent 10 and a plurality of other end side bent portions having apexes on the other end side in the axial direction of the stent 10. 15 and a plurality of gaps 17a and 17b extending between adjacent bent portions, and an endless linear component (specifically, a wavy body) that is annularly continuous.
The annular body 12 adjacent in the axial direction includes the other end side bent portion 15 of the annular body 12 positioned on one end side of the stent and the one end side bent portion 14 of the annular body 12 positioned on the other end side. Connected by.

In the adjacent annular body 12, the one end side bent portion 14 of the other end side annular body 12 and the other end side bent portion 15 of the one end side annular body 12 face each other in the axial direction of the stent and form an adjacent portion. is doing. As shown in FIG. 6, eight adjacent portions are formed at approximately 45 degree intervals with respect to the central axis of the stent 10.
Between the adjacent annular bodies, as shown in FIG. 6, a gap 17 a that extends in the direction of the adjacent annular body from any of the adjacent annular bodies 12 and is located on one side of the adjacent portion. A first protruding linear portion 16a that intrudes into the gap and a gap portion 17b that extends from one of the adjacent annular bodies 12 in the direction of the adjacent annular body and is located on the other side of the adjacent portion. The proximity part deformation | transformation suppression part which consists of two protrusion linear parts 16b is provided in each proximity part.

  In the stent 10 of this embodiment, the first protruding linear portion 16a extends in the direction of the other annular body from one adjacent annular body, and the second protruding linear portion 16b extends from the other adjacent annular body. It extends in the direction of one annular body from the annular body. Further, in the stent of this embodiment, the protruding linear portions 16a and 16b have free ends that end in the gap portions 17a and 17b of the other annular body having a starting end near the bent portion of the one annular body 12. It has become.

  Specifically, as shown in FIG. 6, the first protruding linear portion 16 a is one end-side bent portion located on the side of the other end-side bent portion 15 of the one-end-side annular body 12 that forms the proximity portion. 14 has a starting end, extends substantially parallel to the central axis of the stent 10, passes through a side portion of the one end side bent portion 14 of the annular body 12 on the other end side, and forms an adjacent portion, and has an annular shape on the other end side. The body 12 enters the gap 17a of the body 12 and ends without reaching the bent portion 15 which is the end of the gap 17a. Further, the second protruding linear portion 16b has a start end inside the other end side bent portion 15 located on the side of the one end side bent portion 14 of the annular body 12 on the other end side forming the proximity portion, Extends substantially parallel to the central axis of the stent 10, passes through the side of the bent portion 15 on the other end side of the annular body 12 on one end side that forms a proximity portion, enters the gap 17 b of the annular body 12 on the one end side, Moreover, it terminates without reaching the bent portion 14 which is the end of the gap 17b.

For this reason, the other end side bent portion 15 of the one-end-side annular body 12 and the one end-side bent portion 14 of the other-end-side annular body 12 that form the proximity portion are the first protruding linear portion 16a and the second protruding portion. It is in a state sandwiched between the linear portions 16b. For this reason, the first protruding linear portion 16a that has entered the gap of the annular body on the other end side suppresses deformation of the annular body on the other end side, and similarly enters the gap of the annular body on the one end side. The deformation of the annular body on one end side is suppressed by the second protruding linear portion 16b. The unexpanded stent 10 is hardly bent in any direction and has sufficient rigidity.
And in this stent 10, the other end side bending part 15 of the annular body of the one end side mentioned above and the one end side bending part 14 of the annular body of the other end side are connected by the connection part 3, and thereby the adjacent annular parts The body is connected. In the stent 10 of this embodiment, a plurality of (specifically, two) connecting portions 3 are provided between adjacent annular bodies. In particular, in the stent 10 of this embodiment, two connecting portions 3 are provided so as to be substantially opposed to the central axis of the stent. Three or more connecting portions 3 may be provided so as to be equiangular with respect to the central axis of the stent 10.
And it is preferable that the penetration | invasion length to the gap | interval parts 17a and 17b of the adjacent annular body of the protrusion linear parts 16a and 16b is 0.2-1.5 mm.

Next, an in-vivo stent according to another embodiment of the present invention will be described.
FIG. 7 is a developed view of the in-vivo stent according to another embodiment of the present invention.
In this stent 20, each annular body 22 is arranged so that a linear ring portion 21 that is long in the axial direction of the stent 20 having the one end side bent portion 24 and the other end side bent portion 25 surrounds the central axis of the plurality of stents 20. And the adjacent linear ring part 21 is connected by the junction part 28. FIG.
In the stent 20 of this embodiment, the annular body 22 includes a linear ring portion 21 and a joint portion 28 that connects the side portions of the linear ring portion 21. Specifically, the annular body 22 has a linear ring portion 21 that is long in the axial direction of the stent 20 in the circumferential direction of the plurality of stents, and these are joined by a joint portion 28 at the side portion. The linear ring portion 21 has a substantially rhombus shape, and connects the two bent portions 24 and 25 facing the axial direction of the stent 20, the two bent portions facing the circumferential direction of the stent 20, and four. It has a skewed linear portion of the book. And the junction part 28 has connected the circumferential direction bending part of the one linear ring part which adjoins and adjoins, and the circumferential direction bending part of the other linear ring part. Moreover, 4-10 are suitable for the number of the linear ring parts 21 in one annular body 22. FIG. The shape of the linear ring portion may be a rectangular shape, a polygonal shape having five or more corners that are long in the axial direction, an elliptical shape, or the like.

As shown in FIG. 7, the stent 20 includes a plurality of annular bodies 22 arranged so as to be substantially linear in the axial direction of the stent 20, and a connecting portion 23 that connects adjacent annular bodies 22. Yes.
And in the stent 20 of this Example, as shown in FIG. 7, the one end side bending part 24 and the other end side bending part 25 of an adjacent annular body adjoin, and form the proximity | contact part. Further, the one end side bent portion 24 and the other end side bent portion 25 of the adjacent annular bodies face each other in the axial direction of the stent. As shown in FIG. 7, eight adjacent portions are formed at approximately 45 degree intervals with respect to the central axis of the stent 20.

  As shown in FIG. 7, a gap portion 27 a that extends in the direction of the adjacent annular body from one of the adjacent annular bodies 22 and is located on one side of the adjacent portion is provided between the adjacent annular bodies. A first protruding linear portion 26a that intrudes into the gap and a gap portion 27b that extends from one of the adjacent annular bodies 22 in the direction of the adjacent annular body and that is located on the other side of the adjacent portion. The proximity part deformation | transformation suppression part which consists of two protrusion linear parts 26b is provided in each proximity part.

In the stent 20 of this embodiment, the first protruding linear portion 26a extends in the direction of the other annular body from one adjacent annular body, and the second protruding linear portion 26b extends from the other adjacent annular body. It extends in the direction of one annular body from the annular body. Further, in the stent of this embodiment, the protruding linear portions 26a and 26b have a starting end in the vicinity of the joint portion 28 of one annular body 22, and are free to terminate in the gap portions 27a and 27b of the other annular body. It has an end.
Specifically, as shown in FIG. 7, the first protruding linear portion 26 a is formed on the joint portion 28 located on the side of the other end side bent portion 25 of the annular body 22 on one end side that forms the proximity portion. It has a start end, extends substantially parallel to the central axis of the stent 20, passes through the side of the one end side bent portion 24 of the other end side annular body 22 that forms a proximity portion, and the gap between the other end side annular body 22. It enters into the portion 27a and terminates without reaching the joint portion 28 that is the end of the gap portion 27a. The second protruding linear portion 26b has a starting end at a joint portion 28 located on the side of the one-end-side bent portion 24 of the annular body 22 on the other end side that forms the proximity portion, and the central axis of the stent 20 And passes through the side of the bent portion 25 on the other end side of the annular body 22 on one end side that forms a proximity portion, enters the gap portion 27b of the annular body 22 on one end side, and the gap portion 27b It terminates without reaching the joint portion 28 which is the end of.

  For this reason, the other end side bent portion 25 of the one-end-side annular body 22 and the one end-side bent portion 24 of the other-end-side annular body 22 that form the proximity portion are the first protruding linear portion 26a and the second protruding portion. It is in a state sandwiched between the linear portions 26b. For this reason, the first protruding linear portion 26a that has entered the gap of the annular body on the other end side suppresses deformation of the annular body on the other end side, and similarly enters the gap of the annular body on the one end side. The deformation of the annular body on one end side is suppressed by the second protruding linear portion 26b. The unexpanded stent 20 is hardly bent in any direction and has sufficient rigidity.

And in this stent 20, the other end side bending part 25 of the annular body of the one end side mentioned above and the one end side bending part 24 of the annular body of the other end side are connected by the connecting part 23, so The body is connected. In the stent 20 of this embodiment, a plurality of (specifically, two) connecting portions 23 are provided between adjacent annular bodies. In particular, in the stent 20 of this embodiment, two connecting portions 23 are provided so as to be substantially opposed to the central axis of the stent. Three or more connecting portions 23 may be provided so as to be equiangular with respect to the central axis of the stent 20.
And it is preferable that the penetration | invasion length to the gap | interval parts 27a and 27b of the adjacent annular body of the protrusion linear parts 26a and 26b is 0.2-1.5 mm.

  In all of the above-described embodiments, the protruding linear portion has a starting end in one annular body facing the first protruding linear portion entering the gap portion of the other annular body and the other annular facing. The body has a starting end and a second protruding linear portion that enters the gap portion of one annular body. However, as the protruding linear portion, only one that has a starting end in one (or the other) annular body and enters the gap portion of the other (or one) annular body as in the stent 30 shown in FIG. It may be configured. In this case, the other-end-side bent portion 15 of the one-end-side annular body 12 and the one-end-side bent-portion 14 of the other-end-side annular body 12 that form the proximity portion are sandwiched between the two protruding linear portions 16. It becomes a state.

The stent of the present invention is a so-called balloon that is formed into a substantially tubular body, has a diameter for insertion into a lumen in a living body, and expands when a force that extends radially from the inside of the stent is applied. An expandable stent is preferred.
The material for forming the stent in the balloon expandable stent preferably has a certain degree of biocompatibility. As a material for forming the stent, for example, stainless steel, tantalum or a tantalum alloy, platinum or a platinum alloy, gold or a gold alloy, a cobalt base alloy, or the like can be considered. Moreover, after producing the stent shape, precious metal plating (gold, platinum) may be performed. As stainless steel, SUS316L having the most corrosion resistance is suitable.

The stent is preferably chamfered. As a method for chamfering a stent, after forming the stent into a final shape, it can be performed by chemical polishing, electrolytic polishing or mechanical polishing. The chemical polishing is preferably performed by dipping in a stainless chemical polishing solution. The stainless steel chemical polishing liquid is not particularly limited as long as it can dissolve stainless steel. For example, a mixed liquid composed of hydrochloric acid and nitric acid is used as a basic component, and an organic sulfur compound for adjusting the dissolution rate, smoothing, and imparting gloss. And those to which a surfactant is added are preferred.
Furthermore, it is preferable to anneal after producing the final shape of the stent. By performing the annealing, the flexibility and plasticity of the entire stent are improved, and the indwellability in the bent blood vessel is improved. Compared to the case without annealing, the force that tries to restore the shape before expansion after expanding the stent, especially the force that tries to return to the linear shape when it expands at the bent blood vessel site, is reduced. The physical stimulation applied to the inner wall of the blood vessel can be reduced, and the factor of restenosis can be reduced. Annealing is performed by heating to 900 to 1200 ° C. in an inert gas atmosphere (for example, a mixed gas of nitrogen and hydrogen) and then slowly cooling so that an oxide film is not formed on the stent surface. preferable.

  The stent of the present invention is a so-called self-expanding stent that is formed in a substantially cylindrical shape, is compressed in the direction of the central axis when inserted into the living body, and expands outward when in vivo to restore the shape before compression. There may be. And also as a self-expanding stent, the form of the stent of all the Examples mentioned above can be used.

As a constituent material of the self-expanding stent, a super elastic metal is suitable. As the superelastic metal, a superelastic alloy is preferably used. The superelastic alloy here is generally called a shape memory alloy, and exhibits superelasticity at least at a living body temperature (around 37 ° C.). Particularly preferably, a Ti—Ni alloy of 49 to 53 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, A super elastic metal body such as Si, Sn, Al, Ga), Ni-Al alloy of 36-38 atomic% Al is preferably used. Particularly preferred is the Ti—Ni alloy described above. Further, a Ti—Ni—X alloy in which a part of the Ti—Ni alloy is substituted with 0.01 to 10.0% X (X = Co, Fe, Mn, Cr, V, Al, Nb, W, B, etc.) Or a Ti—Ni—X alloy (X = Cu, Pb, Zr) in which a part of the Ti—Ni alloy is substituted by 0.01 to 30.0% atoms, and the cold work rate Alternatively, mechanical characteristics can be appropriately changed by selecting conditions for final heat treatment. 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 (yield stress during loading) of the superelastic alloy used is 5 to 200 kg / mm ² (22 ° C.), more preferably 8 to 150 kg / mm ^2. Restoring stress (yield stress during unloading) ) Is 3 to 180 kg / mm ² (22 ° C.), more preferably 5 to 130 kg / mm ² . Superelasticity here means that even if it is deformed (bending, pulling, compressing) to a region where normal metal is plastically deformed at the operating temperature, it will recover to its almost uncompressed shape without the need for heating after the deformation is released. It means to do.

  And in the stents of all the embodiments described above, the diameter of the stent when unexpanded (or compressed) is preferably about 0.8 to 1.8 mm, and particularly 0.9 to 1.4 mm. More preferred. The length of the stent when not expanded (or when not compressed) is preferably about 9 to 40 mm. The length of one annular body is preferably about 0.7 to 2.0 mm. Further, the number of bent portions on one end side and the other end side of one annular body is preferably 4-8, and particularly preferably 5-7. Moreover, as a number of cyclic bodies, 4-20 are suitable. The diameter of the stent during molding (before compression) is preferably about 1.5 to 3.5 mm, and more preferably 2.0 to 3.0 mm. Further, the thickness of the stent is preferably about 0.05 to 0.15 mm, particularly preferably 0.08 to 0.12 mm, and the width of the linear component is 0.07 to 0.00. About 15 mm is preferable, and 0.08 to 0.13 mm is particularly preferable.

Next, the living organ dilator according to the present invention will be described with reference to embodiments shown in the drawings.
FIG. 9 is a front view of the living organ dilator according to the embodiment of the present invention. FIG. 10 is an enlarged partial cross-sectional view of the distal end portion of the living organ dilator shown in FIG. FIG. 11 is an explanatory diagram for explaining the operation of the living organ dilator according to the embodiment of the present invention.
The living organ dilator 100 of the present invention encloses a tubular shaft main body 102, a foldable and expandable balloon 103 provided at the distal end of the shaft main body 102, and a balloon 103 in a folded state. And a stent 1 that is expanded by expansion of the balloon 103.

And as the stent 1, the stent 1 mentioned above and the stent of all the examples mentioned above can be used.
A living organ expanding device 100 of this embodiment includes the above-described stent 1 and a tube-shaped living organ expanding device main body 101 to which the stent 1 is attached.
The living organ expanding instrument main body 101 includes a tube-shaped shaft main body 102 and a foldable and expandable balloon 103 provided at the distal end of the shaft main body. The stent 1 includes the balloon 103 in a folded state. It is mounted so as to be encapsulated and expanded by expansion of the balloon 103.
As the stent 1, the stents of all the embodiments described above can be used. The stent used here is a so-called balloon expandable stent that has a diameter for insertion into a lumen in a living body and is expandable when a force that expands radially from the inside of the tubular body is applied. Used.

In the living organ dilator 100 of this embodiment, as shown in FIG. 10, the shaft main body 102 has one end opened at the tip of the shaft main body 102 and the other end at the rear end of the shaft main body 102. An opening guide wire lumen 115 is provided.
The living organ expanding instrument main body 101 includes a shaft main body 102 and a stent expansion balloon 103 fixed to the distal end of the shaft main body 102, and the stent 1 is mounted on the balloon 103. The shaft body 102 includes an inner tube 112, an outer tube 113, and a branch hub 110.

  As shown in FIG. 10, the inner tube 112 is a tube body including a guide wire lumen 115 for inserting a guide wire therein. The inner tube 112 has a length of 100 to 2500 mm, more preferably 250 to 2000 mm, and an outer diameter of 0.1 to 1.0 mm, more preferably 0.3 to 0.7 mm, and a wall thickness of 10 to 10. It is 250 micrometers, More preferably, it is 20-100 micrometers. The inner tube 112 is inserted into the outer tube 113, and the tip of the inner tube 112 protrudes from the outer tube 113. A balloon expanding lumen 116 is formed by the outer surface of the inner tube 112 and the inner surface of the outer tube 113, and has a sufficient volume. The outer tube 113 is a tube body in which the inner tube 112 is inserted and the tip is located at a portion slightly retracted from the tip of the inner tube 112.

The outer tube 113 has a length of 100 to 2500 mm, more preferably 250 to 2000 mm, and an outer diameter of 0.5 to 1.5 mm, more preferably 0.7 to 1.1 mm, and a wall thickness of 25 to 25 mm. It is 200 μm, more preferably 50 to 100 μm.
In the living organ dilator 100 of this embodiment, the outer tube 113 is formed by the distal end side outer tube 113a and the main body side outer tube 113b, and both are joined. The distal end side outer tube 113a has a tapered diameter at a portion closer to the distal end than the joint portion with the main body side outer tube 113b, and the distal end side has a smaller diameter than the tapered portion.
The outer diameter at the small diameter portion of the distal end side outer tube 113a is 0.50 to 1.5 mm, preferably 0.60 to 1.1 mm. Further, the base end portion of the distal end side outer tube 113a and the outer diameter of the main body side outer tube 113b are 0.75 to 1.5 mm, preferably 0.9 to 1.1 mm.

The balloon 103 has a front end side joint portion 103a and a rear end side joint portion 103b. The front end side joint portion 103a is fixed at a position slightly rear end side from the front end of the inner tube 112, and the rear end side joint portion 103b. Is fixed to the tip of the outer tube. The balloon 103 communicates with the balloon expansion lumen 116 in the vicinity of the proximal end portion.
As a material for forming the inner tube 112 and the outer tube 113, a material having a certain degree of flexibility is preferable. For example, polyolefin (for example, polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, etc.) Further, thermoplastic resins such as polyvinyl chloride, polyamide elastomer and polyurethane, silicone rubber, latex rubber and the like can be used, preferably the above-mentioned thermoplastic resin, more preferably polyolefin.

As shown in FIG. 10, the balloon 103 is foldable, and can be folded on the outer periphery of the inner tube 112 when not expanded. As shown in FIG. 10, the balloon 103 has an expandable portion that is a cylindrical portion (preferably, a cylindrical portion) having substantially the same diameter so that the attached stent 1 can be expanded. The substantially cylindrical portion may not be a perfect cylinder, but may be a polygonal column. As described above, the balloon 103 is liquid-tightly fixed to the inner tube 112 with the front end side joint portion 103a and the rear end side joint portion 103b to the front end of the outer tube 113 with an adhesive or heat fusion. . Further, in this balloon 103, the space between the expandable portion and the joint portion is formed in a tapered shape.
The balloon 103 forms an expansion space 103 c between the inner surface of the balloon 103 and the outer surface of the inner tube 112. The expansion space 103c communicates with the expansion lumen 116 on the entire periphery at the rear end. In this way, the rear end of the balloon 103 communicates with the expansion lumen having a relatively large volume, so that the expansion fluid can be reliably injected into the balloon from the expansion lumen 116.

As a material for forming the balloon 103, a material having a certain degree of flexibility is preferable. For example, polyolefin (for example, polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, cross-linked ethylene-vinyl acetate). Copolymer), polyvinyl chloride, polyamide elastomer, polyurethane, polyester (for example, polyethylene terephthalate), thermoplastic resin such as polyarylene sulfide (for example, polyphenylene sulfide), silicone rubber, latex rubber, and the like. In particular, a stretchable material is preferable, and the balloon 103 is preferably biaxially stretched having high strength and expansion force.
As the size of the balloon 103, the outer diameter of the cylindrical portion (expandable portion) when expanded is 2 to 4 mm, preferably 2.5 to 3.5 mm, and the length is 10 to 50 mm, preferably 20-40 mm. Moreover, the outer diameter of the front end side joint portion 103a is 0.9 to 1.5 mm, preferably 1 to 1.3 mm, and the length is 1 to 5 mm, preferably 1 to 1.3 mm. Moreover, the outer diameter of the rear end side joint portion 103b is 1 to 1.6 mm, preferably 1.1 to 1.5 mm, and the length is 1 to 5 mm, preferably 2 to 4 mm.

As shown in FIGS. 10 and 11, the living organ dilator 100 has two Xs fixed to the outer surface of the shaft main body at both ends of the cylindrical portion (expandable portion) when expanded. Line contrast members 117 and 118 are provided. In addition, it is good also as what has two X-ray contrast contrast members fixed to the outer surface of the shaft main-body part 102 (in this embodiment, the inner pipe | tube 112) of the position which becomes the both ends of the predetermined length of the center part of the stent 1. FIG. Furthermore, it is good also as what provides the single X-ray contrast property member fixed to the outer surface of the shaft main-body part of the position used as the center part of a stent.
The X-ray contrast members 117 and 118 are preferably ring-shaped members having a predetermined length, or those obtained by winding a linear body in a coil shape, and the forming material is, for example, gold, platinum, tungsten, or the like. Those alloys or silver-palladium alloys are suitable.

  The stent 1 is attached so as to encapsulate the balloon 103. The stent is manufactured by processing a metal pipe having a smaller diameter than that at the time of stent expansion and an inner diameter larger than the outer diameter of the folded balloon. Then, a balloon is inserted into the manufactured stent, and a uniform force is applied to the outer surface of the stent inward to reduce the diameter, thereby forming a product-state stent. That is, the above stent 1 is completed by compression mounting on the balloon.

  A linear rigidity imparting body (not shown) may be inserted between the inner tube 112 and the outer tube 113 (within the balloon expansion lumen 116). The rigidity imparting body prevents extreme bending of the main body 102 of the living organ expanding device 100 at the bent portion without significantly reducing the flexibility of the living organ expanding device 100, and the distal end of the living organ expanding device 100. Easy to push the part. It is preferable that the tip of the rigidity imparting body has a smaller diameter than other parts by a method such as polishing. Moreover, it is preferable that the rigidity imparting body has the tip of the small diameter portion extending to the vicinity of the tip of the outer tube 113. The rigidity imparting body is preferably a metal wire, and is preferably an elastic metal such as stainless steel having a wire diameter of 0.05 to 1.50 mm, preferably 0.10 to 1.00 mm, a superelastic alloy, etc. Is a high-strength stainless steel for springs and a superelastic alloy wire.

In the living organ dilator 100 of this embodiment, as shown in FIG. 9, a branch hub 110 is fixed to the proximal end. The branch hub 110 has a guide wire inlet 109 that communicates with the guide wire lumen 115 to form a guide wire port, and communicates with the inner tube hub fixed to the inner tube 112 and the balloon expansion lumen 116, and the injection port 111. And an outer tube hub fixed to the outer tube 113. The outer tube hub and the inner tube hub are fixed to each other. As a material for forming the branch hub 110, a thermoplastic resin such as polycarbonate, polyamide, polysulfone, polyarylate, and methacrylate-butylene-styrene copolymer can be preferably used.
Note that the structure of the living organ dilator is not limited to the above, and may have a guide wire insertion port communicating with the guide wire lumen at an intermediate portion of the living organ dilator.

FIG. 12 is a partially omitted front view of a living organ dilator according to another embodiment of the present invention. FIG. 13 is an enlarged vertical cross-sectional view of the vicinity of the distal end portion of the living organ dilator shown in FIG.
The living organ dilator 200 of this embodiment is configured to slidably pass through the sheath 202, the stent 201 housed in the distal end portion of the sheath 202, and to release the stent 201 from the distal end of the sheath 202. The inner tube 204 is provided.
As the stent 201, the above-described self-expanding stent is used which is formed in a cylindrical shape, is compressed in the direction of the central axis when inserted into the living body, and is expanded outwardly when being placed in the living body and can be restored to the shape before compression. The
As shown in FIG. 12, the living organ dilator 200 of this embodiment includes a sheath 202, a self-expanding stent 201, and an inner tube 204.

As shown in FIGS. 12 and 13, the sheath 202 is a tubular body, and the front end and the rear end are open. The distal end opening functions as a discharge port of the stent 201 when the stent 201 is placed in a stenosis in the body cavity. When the stent 201 is released from the distal end opening, the stress load is released and the stent 201 expands and is restored to the shape before compression. The distal end portion of the sheath 202 is a stent housing part 222 that houses the stent 201 therein. The sheath 202 includes a side hole 221 provided on the proximal end side with respect to the storage part 222. The side hole 221 is for leading the guide wire to the outside.
The outer diameter of the sheath 202 is preferably about 1.0 to 4.0 mm, and particularly preferably 1.5 to 3.0 mm. Further, the inner diameter of the sheath 202 is preferably about 1.0 to 2.5 mm. The length of the sheath 202 is preferably 300 to 2500 mm, particularly about 300 to 2000 mm.

A sheath hub 206 is fixed to the proximal end portion of the sheath 202 as shown in FIG. The sheath hub 206 includes a sheath hub main body and a valve body (not shown) that is housed in the sheath hub main body and that holds the inner tube 204 in a slidable and liquid-tight manner. The sheath hub 206 includes a side port 261 that branches obliquely rearward from the vicinity of the center of the sheath hub body. The sheath hub 206 is preferably provided with an inner tube locking mechanism that restricts the movement of the inner tube 204.
As shown in FIGS. 12 and 13, the inner tube 204 includes a shaft-shaped inner tube main body 240, a tip 247 provided at the tip of the inner tube main body 240 and protruding from the tip of the sheath 202, and the inner tube And an inner tube hub 207 fixed to the base end portion of the main body 240.

  The tip 247 preferably protrudes from the tip of the sheath 202 and is formed in a tapered shape that gradually decreases in diameter toward the tip, as shown in FIG. By forming in this way, the insertion into the constricted portion is facilitated. Moreover, it is preferable that the inner tube 204 includes a stopper that is provided on the distal end side of the stent 201 and prevents the sheath from moving in the distal direction. The proximal end of the distal end portion 247 of the inner tube 204 can be brought into contact with the distal end of the sheath 202, and functions as the stopper.

  Further, as shown in FIG. 13, the inner tube 204 includes two protrusions 243 and 245 for holding the self-expanding stent 201. The protrusions 243 and 245 are preferably annular protrusions. On the proximal end side of the distal end portion 247 of the inner tube 204, a stent holding projection 243 is provided. A stent release protrusion 245 is provided on the proximal side of the stent holding protrusion 243 by a predetermined distance. The stent 201 is disposed between the two protrusions 243 and 245. The outer diameters of these protrusions 243 and 245 are large enough to abut on a compressed stent 201 described later. For this reason, the movement of the stent 201 to the distal end side is restricted by the protruding portion 243, and the movement to the proximal end side is restricted by the protruding portion 245. Further, when the sheath 202 moves to the proximal end side, the stent 201 stays at the position by the protruding portion 245, is exposed from the sheath 202, and is discharged. Furthermore, it is preferable that the proximal end side of the stent release protrusion 245 is a tapered portion 246 that gradually decreases in diameter toward the proximal end side, as shown in FIG. Similarly, the proximal end side of the stent holding projection 243 is preferably a tapered portion 244 that gradually decreases in diameter toward the proximal end side, as shown in FIG. In this way, when the inner tube 204 protrudes from the distal end of the sheath 202 and the stent 201 is released from the sheath, the protruding portion is caught by the distal end of the sheath when the inner tube 204 is re-stored in the sheath 202. To prevent that. Moreover, the protrusions 243 and 245 may be formed of different members from an X-ray contrast material. Thereby, the position of the stent can be accurately grasped under X-ray contrast, and the procedure becomes easier.

As shown in FIG. 13, the inner tube 204 includes a lumen 241 extending from the distal end to at least the proximal end side of the stent housing portion 222 of the sheath 202, and an inner tube side hole 242 communicating with the lumen 241 on the proximal end side from the stent housing portion. And. In the living organ dilator 200 of this embodiment, the lumen 241 terminates at the side hole 242 formation site. The lumen 241 is for inserting one end of a guide wire from the distal end of the living organ dilator 200, partially passing through the inner tube, and then leading out from the side surface of the inner tube. The inner tube side hole 242 is located slightly on the distal end side of the living organ dilator 200 from the sheath side hole 221. The center of the inner tube side hole 242 is preferably 0.5 to 10 mm from the center of the sheath side hole 221.
Note that the living organ dilator is not limited to the above-described type, and the lumen 241 may extend to the proximal end of the inner tube. In this case, the side hole 221 of the sheath becomes unnecessary.
The inner tube 204 penetrates through the sheath 202 and protrudes from the rear end opening of the sheath 202. As shown in FIG. 12, an inner tube hub 207 is fixed to the proximal end portion of the inner tube 204.

FIG. 1 is a front view of an in-vivo stent according to an embodiment of the present invention. FIG. 2 is a development view of the in-vivo stent of FIG. FIG. 3 is a partially enlarged view of FIG. FIG. 4 is a front view of the in-vivo indwelling stent of FIG. 1 at the time of expansion. FIG. 5 is a developed view of the in-vivo indwelling stent of FIG. 1 during expansion. FIG. 6 is a developed view of a stent for in vivo placement according to another embodiment of the present invention. FIG. 7 is a developed view of the in-vivo stent according to another embodiment of the present invention. FIG. 8 is a developed view of the in-vivo stent according to another embodiment of the present invention. FIG. 9 is a front view of the living organ dilator according to the embodiment of the present invention. FIG. 10 is an enlarged partial cross-sectional view of the distal end portion of the living organ dilator shown in FIG. FIG. 11 is a diagram for explaining the operation of the living organ dilator according to the embodiment of the present invention. FIG. 12 is a partially omitted front view of a living organ dilator according to another embodiment of the present invention. FIG. 13 is an enlarged vertical cross-sectional view of the vicinity of the distal end portion of the living organ dilator shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 In vivo indwelling stent 2 Ring body 3 Connection part 4a, 4b One end side bending part 5a, 5b Other end side bending part 6a, 6b Protruding linear part 7a, 7b Gap part

Claims (18)

A stent for in-vivo indwelling that adheres to in-vivo tissue by being deformed during in-dwelling operation,
The stent is formed in an annular shape by linear components, and an annular body having a plurality of one end side bent portions, a plurality of other end side bent portions, and a plurality of gap portions extending between the adjacent bent portions is provided in the axial direction. A plurality of adjacent annular bodies are connected by a connecting portion, and the stent has one end-side bent portion of one adjacent annular body and the other end-side bent portion of the other annular body. There are at least three adjacent sites at approximately the same angle with respect to the central axis of the stent, and the stent extends from any one of the adjacent annular bodies, and the adjacent site A first protruding linear portion that passes through one side portion of the adjacent annular body and enters the gap portion of the adjacent annular body, and extends from any annular body of the adjacent annular body, and the other of the adjacent portions Pass through the side , At least two of the proximate sites, each having a proximate site deformation suppressing portion that includes a second projecting linear portion that enters the gap between adjacent annular bodies, and the stent further enters the living body. During the indwelling operation, at least the protruding linear portion is deformed in a direction in which the bent portion forming the terminal end of the gap portion into which the protruding linear portion has invaded is deformed to open, so that the protruding linear portion forms the linear portion forming the gap portion. A stent for in-vivo placement, characterized in that 2. The in-vivo indwelling stent according to claim 1, wherein the proximity part deformation suppressing portion is provided in at least two of the proximity parts that do not face the central axis of the stent. 2. The stent according to claim 1, wherein the stent has four neighboring sites at an interval of approximately 90 degrees with respect to the central axis of the stent, and the proximal site deformation suppressing portions are provided at least in two neighboring sites that do not face each other. The stent for in-vivo indwelling described. 2. The stent according to claim 1, wherein the stent has three adjacent portions at approximately 120 degrees intervals with respect to the central axis of the stent, and the proximal portion deformation suppression portions are provided at two or more adjacent portions. In vivo indwelling stent. The in-vivo indwelling stent according to any one of claims 1 to 4, wherein each of the adjacent portions is located between the first protruding linear portion and the second protruding linear portion. The first protruding linear portion extends in the direction of the other annular body from one of the adjacent annular bodies, and the second protruding linear portion is one of the other adjacent annular bodies. The in-vivo stent according to any one of claims 1 to 5, which extends in the annular body direction. The bent portion that forms the terminal end of the gap portion into which the protruding linear portion intrudes is larger than other bent portions when the stent is expanded. In vivo indwelling stent. 8. The protruding linear portion has a starting end at or near the bent portion of one of the annular bodies and a free end that terminates in the gap portion of the other annular body. A stent for in-vivo placement according to any one of the above. The protruding linear portion has a starting end inside the bending portion located on the side of the bending portion forming the proximity portion, and has a free end terminating in the gap portion of the other annular body. The in-vivo indwelling stent according to any one of claims 1 to 7. Each annular body includes a plurality of one end side bent portions having apexes on one end side in the axial direction of the stent, and a plurality of other end side bent portions having apexes on the other end side in the axial direction of the stent, The in vivo indwelling stent according to any one of claims 1 to 9, wherein the stent is an endless annular body that is continuous in an annular shape and has a plurality of connecting linear portions connecting the one end-side bent portions and the other end-side bent portions. . The in-vivo indwelling stent according to any one of claims 1 to 10, wherein the one end side bent portion and the other end side bent portion at the proximity portion are slightly shifted in a circumferential direction of the stent. The in-vivo stent according to any one of claims 1 to 10, wherein the one-end-side bent portion and the other-end-side bent portion in the proximity portion face each other in the axial direction of the stent. Each annular body is arranged such that linear ring portions that are long in the axial direction of the stent having the one end side bent portion and the other end side bent portion surround the central axis of the plurality of stents, and adjacent linear rings. The in-vivo indwelling stent according to any one of claims 1 to 9, wherein the part is composed of an annular body connected by a joint. The raw protruding portion has a starting end in the vicinity of the joint portion of one of the annular bodies and a free end that terminates in the gap portion of the other annular body. Indwelling stent. 2. The stent is formed in a substantially tubular body, has a diameter for insertion into a living body lumen, and expands when a force spreading radially from the inside of the stent is applied. The stent for indwelling in any one of thru | or 14. A tubular shaft main body, a foldable and expandable balloon provided at the distal end of the shaft main body, and a balloon mounted so as to enclose the balloon in a folded state and expanded by expansion of the balloon A living organ dilating device comprising the stent according to claim 15. The stent according to any one of claims 1 to 14, wherein the stent is formed in a substantially cylindrical shape, is compressed in the direction of the central axis when inserted into a living body, and expands outward when placed in the living body to restore a shape before compression. The stent for in-vivo indwelling. 18. A sheath comprising: a sheath; the stent of claim 17 housed in a distal end portion of the sheath; and an inner tube for slidably passing through the sheath and pushing the stent from the distal end of the sheath. Living organ expansion device.

Images