JP2013192861A - In-vivo indwelling stent and biological organ dilator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an in-vivo indwelling stent having excellent dilation maintenance force after dilation and arrival easiness at a target region, and not having deformation directionality.SOLUTION: In a stent 1, a plurality of annular bodies 2 are arranged in the axial direction, and are connected by connection parts 3. Each annular body 2 has a plurality of one end side curve parts 21 and the other end side curve parts 22. One set or a plurality of sets of the adjacent annular bodies 2 has: a first projection part 4 formed in the other end side curve part 22a of one annular body 2a of the adjacent annular bodies 2 approaching each other in time of dilation; and a second projection part 5 formed in the one end side curve part 21a of the other annular body 2b. The first projection part 4 and the second projection part 5 form a post-stent-dilation diameter reduction restriction part allowing getting-over and, after the getting-over, abutting when force in a compression direction is imparted to the stent.

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 lumen in a living body such as a blood vessel, a bile duct, a trachea, an esophagus, or a urethra.

In order to treat various diseases caused by stenosis or occlusion of blood vessels or other in-vivo lumens, stents are generally expanded in the stenosis or occlusion site and placed there to secure the lumen. Specifically, it is a tubular medical device.
Since the stent is inserted from outside the body into the body, the diameter is small at the time of insertion. 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. A stent is attached to a catheter or the like in a thin state, inserted into a living body, expanded in some way at a target site, and tightly 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 does not have an expansion function in the stent itself. After the stent mounted on the balloon is inserted into the target site, the balloon is expanded, and the stent is expanded (plastic deformation) by the expansion force of the balloon, so that the inner surface of the target lumen Fix in close contact. This type of stent requires the above-described stent expansion operation.
The majority of stents used for endovascular treatment, particularly coronary artery treatment, are balloon-expanded. And as a stent, it is desirable that the shape after expansion can be maintained, that is, so-called expansion maintenance force is high.

In order to provide a high expansion maintaining force, the following stent having a locking mechanism has been proposed.
Japanese Patent Application Laid-Open No. 7-531 (Patent Document 1) has a plurality of rings having at least one pair of overlap edges and a plurality of teeth provided on at least one of the overlap edges. Disclosed is a stent that can be expanded from the ring first diameter to an adjustable expandable diameter, whereby the teeth engage in an interlocking relationship to hold the ring in the expanded diameter configuration. ing.
Japanese Patent Laid-Open No. 10-113397 (Patent Document 2) discloses a stent that is positioned in a blood vessel and includes a plurality of mutually connected tubular bands, and at least one of the bands is a second one. A first end that overlaps the end of the first end and is movable relative to the second end so as to re-form the band between at least a contracted configuration and a fully expanded configuration; and one vicinity of the end And at least one receiving means disposed on the first edge and a first tab protruding from the first edge near the other of the ends, with respect to the central axis of the band A receiving portion located in a generally vertical plane, the receiving portion engaging the receiving means and including a first tab shaped to prevent the band from returning toward a retracted configuration Stent characterized by It has been disclosed.

  Further, the applicant of the present application has proposed Japanese Patent Application Laid-Open No. 2009-160098 (Patent Document 3). The stent 1 of Patent Document 3 includes a plurality of annular units 2 arranged in the axial direction, and a connecting portion 3 that connects adjacent annular units. The annular unit 2 includes a linear ring portion 4 extending in the axial direction of the stent 1 in the circumferential direction of the plurality of stents. Each of the linear ring portions expands in the circumferential direction and contracts in the axial direction when the stent is expanded, and is deformed into a reduced diameter suppressing form having spring elasticity without inhibiting the expansion of the stent. A diameter-reducing linear portion 7 that restricts deformation of the portion in the circumferential reduction direction is provided.

JP 7-531 A Japanese Patent Laid-Open No. 10-113397 JP 2009-160098 A

In the thing of the said patent document 1 and the patent document 2, the high expansion maintenance force after expansion can be anticipated. However, the thing of patent document 1 has an overlap part, and the thing of patent document 2 has an overlap part, and the mechanical characteristic as a whole stent is not a homogeneous thing, and with respect to deformation | transformation of indwelling sites, such as a blood vessel. The follow-up is not good and the direction is difficult to deform. In the thing of patent document 3, although a mechanical characteristic is entirely uniform and does not have a deformation directionality, it is effective, but all the linear ring parts 4 are provided with the diameter-reducing suppression linear part 7. Therefore, as a whole that retains a certain degree of elastic deformability, it has high rigidity. Therefore, when inserting into the target site, it becomes difficult to pass a bent blood vessel or the like, and the target site may not be reached.
Therefore, the present invention provides a stent for indwelling in vivo that has a good expansion maintaining force after expansion, reachability to a target site, and does not have deformation directionality, and a living organ expansion device using the same. It is to provide.

What achieves the above object is as follows.
(1) A stent for in vivo placement in which a plurality of annular bodies formed in an annular shape by linear components are arranged in an axial direction and adjacent annular bodies are connected by a connecting portion,
Each annular body has 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 one or a plurality of sets of adjacent annular bodies include a first protrusion provided at the other-end-side bent portion of the adjacent one of the adjacent annular bodies at the time of expansion, and the other adjacent annular body. A second projecting portion provided on the one-end-side bent portion, and the first projecting portion and the second projecting portion are able to get over when the stent is expanded, and after getting over the stent, A stent for indwelling in vivo, which forms a diameter-restricting portion after stent expansion that can contact when force is applied.

(2) The in vivo indwelling stent according to (1), wherein the first protrusion and the second protrusion extend in a circumferential direction of the annular body and in different directions.
(3) The one end side bent portion, which is connected to the other end side bent portion provided with the first protruding portion by a linear portion and is positioned in the circumferential direction in which the first protruding portion extends, is easily deformable. The other end side bent portion, which is connected to the one end side bent portion provided with the second projecting portion and the linear portion, and is located in the circumferential direction in which the second projecting portion extends, The in-vivo indwelling stent according to (2), wherein the stent is an easily deformable bent portion.
(4) One end side bent portion connected to the other end side bent portion provided with the first protruding portion by a linear portion and positioned in the circumferential direction in which the first protruding portion extends, and the one end side The other end-side bent portion that is connected by the bent portion and the linear portion and is positioned in the circumferential direction in which the first protruding portion extends is an easily deformable bending portion, and has an annular shape having the first protruding portion. The body according to (2) or (3), wherein the body includes an easily deformable linear portion formed by the two easily deformable bent portions and a linear portion that connects the two easily deformable bent portions. In vivo indwelling stent.
(5) The other end side bent portion connected to the one end side bent portion provided with the second projecting portion and the linear portion, and located in the circumferential direction in which the second projecting portion extends, and the other end One end side bent portion that is connected by a side bent portion and a linear portion and is positioned in the circumferential direction in which the second protruding portion extends is an easily deformable bent portion, and an annular shape having the second protruding portion. Any of (2) to (4) above, wherein the body has an easily deformable linear portion formed by the two easily deformable bent portions and a linear portion connecting the two easily deformable bent portions. The stent for in-vivo indwelling.
(6) The first projecting portion and the second projecting portion include a meshing portion that extends in a separating direction before getting over, and extends in a close direction after getting over and can be meshed. (1) The stent for indwelling in any one of (5).
(7) The first protrusion and the second protrusion have inclined sides for contacting and riding on when the stent is expanded, and the inclined side of the first protrusion and the second protrusion The indwelling stent according to any one of the above (1) to (6), wherein the inclined side is inclined with respect to the central axis of the stent and is substantially parallel.
(8) The meshing portion of the first projecting portion and the meshing portion of the second projecting portion have a meshing inclined side for meshing after getting over, and the meshing inclined side of the first projecting portion; The indwelling stent according to any one of (1) to (7), wherein the meshing inclined side of the second projecting portion is inclined and substantially parallel to the central axis of the stent.
(9) Any of the above (2) to (8), wherein the first projecting portion and the second projecting portion have a substantially triangular shape extending in a circumferential direction and different directions of the annular body. The stent for in-vivo indwelling.
(10) The in-vivo body according to any one of (1) to (9), wherein the diameter-reducing restriction portion after stent expansion is provided in at least one pair of the annular bodies facing each other located in a central portion of the stent. Indwelling stent.
(11) The in-vivo body according to any one of (1) to (10), wherein the diameter-reducing restriction portion after stent expansion is provided in the annular body facing each other at one end and the other end of the stent. Indwelling stent.
(12) The stent (1) is a stent that is formed into a substantially tubular body, has a diameter for insertion into a living body lumen, and is expandable when a force that expands radially from the inside is applied. ) To the in vivo stent according to any one of (11) to (11).

Moreover, what achieves the said objective is as follows.
(13) A tubular shaft main body, a foldable and expandable balloon provided at the distal end of the shaft main body, and a balloon mounted on the balloon so as to enclose the balloon in a folded state. A living organ dilator comprising the stent according to (12) that is expanded by expansion.

In the indwelling stent of the present invention, a plurality of annular bodies formed in an annular shape by linear components are arranged in the axial direction, adjacent annular bodies are connected by a connecting portion, and each annular body is further connected. The body has 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 adjacent annular bodies of the set are provided at the first projecting portion provided at the other end-side bent portion of the adjacent one of the adjacent annular bodies and the one end-side bent portion of the other adjacent annular body at the time of expansion. A second protrusion, and the first protrusion and the second protrusion can be overcome when the stent is expanded, and can be contacted when a force in the compression direction is applied to the stent after the extension. A reduced diameter restricting portion is formed after stent expansion.
In particular, the diameter-restricting restricting portion after stent expansion comes into contact when a force in the compression direction is applied to the stent, and thus has a good expansion maintaining force after expansion. Since it is in a non-contact state before expansion, it does not hinder bending between adjacent annular bodies, and when inserting a stent into a target site, it can easily pass through a bent blood vessel, etc. It is possible to reach. Further, this stent has substantially uniform mechanical characteristics as a whole, and does not impart deformation directionality to the stent unfavorably, including the diameter-reducing restriction portion after stent expansion.

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 development view of the in-vivo indwelling stent of FIG. FIG. 4 is a partially enlarged view of FIG. FIG. 5 is an explanatory view for explaining a cross-sectional form of the first projecting portion and the second projecting portion of the in-vivo indwelling stent of the present invention. FIG. 6 is an explanatory view for explaining a cross-sectional configuration of the first protrusion and the second protrusion of the in-vivo stent according to another embodiment of the present invention. FIG. 7 is a developed view of the in-vivo indwelling stent of FIG. 1 at the time of expansion. FIG. 8 is a development view of the in-vivo indwelling stent according to another embodiment of the present invention. FIG. 9 is an explanatory diagram for explaining a state when the in-vivo indwelling stent shown in FIG. 8 is expanded. FIG. 10 is a development view at the time of manufacturing an in-vivo stent according to another embodiment of the present invention. FIG. 11 is a development view at the time of manufacturing a stent for in vivo placement according to another embodiment of the present invention. FIG. 12 is a developed view of the in-vivo indwelling stent according to another embodiment of the present invention. FIG. 13 is a front view of the living organ dilator according to the present invention. FIG. 14 is an enlarged partial cross-sectional view of the distal end portion of the biological organ dilator shown in FIG. FIG. 15 is an explanatory diagram for explaining the operation of the living organ dilator according to the embodiment of the present invention.

The in-vivo stent according to the present invention will be described using the following preferred embodiments.
In the indwelling stent 1 of the present invention, a plurality of annular bodies 2 formed in an annular shape by linear components are arranged in the axial direction, and adjacent annular bodies 2 are connected by a connecting portion 3. Each annular body 2 has a plurality of one end side bent portions 21 having apexes on one end side in the axial direction of the stent 1 and a plurality of other end side bent portions 22 having apexes on the other end side in the axial direction of the stent, Further, one or a plurality of sets of adjacent annular bodies 2 includes a first projecting portion 4 provided on the other end side bent portion 22a of the adjacent one of the annular bodies 2a adjacent to each other and the other adjacent one. And a second projecting portion 5 provided at one end-side bent portion 21a of the annular body 2b. The first projecting portion 4 and the second projecting portion 5 are capable of getting over when the stent 1 is expanded, and after the expansion, the diameter of the stent after the stent expansion can be contacted when a force in the compression direction is applied to the stent. It forms a regulation part.

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 FIGS. 1 to 3, the stent 1 of this embodiment has a configuration in which a plurality of annular bodies 2 are arranged so as to be adjacent in the axial direction and are connected to each other.
Each annular body 2 includes a plurality of one end side bent portions 21 having apexes on one end side in the axial direction of the stent 1 and a plurality of other end side bent portions 22 having apexes on the other end side in the axial direction of the stent 1. And 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 3, the annular body 2 includes a plurality of one end side bent portions 21 located on one end side of the stent and a plurality of other end sides located on the other end side. The wave-like annular body includes a bent portion 22, a one-end-side bent portion 21, and a linear portion connecting the other-end-side bent portion 22. And the linear part is a substantially linear part. The annular body 2 adjacent in the axial direction has the other end side bent portion 22 of the annular body 2 positioned on one end side of the stent and the one end side bent portion 21 of the annular body 2 positioned on the other end side, and Are arranged so as to face each other (in other words, aligned in the axial direction of the stent), and are connected by the connecting portion 3.
Then, the stent 1 is inserted into the living body in the state shown in FIG. 1, and expands by applying a force spreading in the radial direction from the inside of the stent.
As shown in FIG. 1 and FIG. 2 which is a developed view thereof, the annular body in the stent 1 of this embodiment includes a plurality of one end side bent portions 21, other end side bent portions 22 and linear portions having substantially the same pitch. It is an endless wavy body that has an annular shape and is continuous. In addition, 4-10 are suitable for the number of the one end side bending parts (or other end side bending parts) in each annular body. And in the stent 1 of this Example, the one connection part 3 is provided between the adjacent annular bodies.

In the stent 1 of the present invention, one or a plurality of sets of adjacent annular bodies 2 are first projecting portions provided on the other end side bent portion 22a of the adjacent one of the annular bodies 2a when expanded. 4 and a second protrusion 5 provided at one end-side bent portion 21a of the other adjacent annular body 2b. The first projecting portion 4 and the second projecting portion 5 are capable of getting over when the stent 1 is expanded, and after the expansion, the diameter of the stent after the stent expansion can be contacted when a force in the compression direction is applied to the stent. It forms a regulation part.
The diameter-restricting restricting portion after stent expansion (in other words, the first projecting portion 4 and the second projecting portion 5 facing each other) may be provided between at least one pair of facing annular bodies located in the central portion of the stent. preferable. In addition, the diameter-restricting restricting portion after stent expansion (in other words, the first projecting portion 4 and the second projecting portion 5 facing each other) are provided between facing annular bodies located at one end and the other end of the stent. It is preferable. In particular, the diameter-restricting restricting portion after stent expansion (in other words, the first projecting portion 4 and the second projecting portion 5 facing each other) are arranged between at least one pair of facing annular bodies located at the center of the stent and one end of the stent. It is preferable that it is provided in both between the annular bodies located in a part and an other end part.

In the stent 1 of this embodiment, the annular body 2a having the first protruding portion 4 at the other end side bent portion 22a and the annular body 2b having the second protruding portion at the one end side bent portion 21a are arranged in the axial direction. They are arranged alternately. The annular body 2a is located on one end side, the annular body 2b is located on the other end side, the annular body 2a and the annular body 2b face each other, and the first protrusion 4 and the second protrusion 5 are also substantially It has become something to face. Further, in the stent 1 of this embodiment, the annular body 2b is located on one end side, the annular body 2a is located on the other end side, and between the annular bodies facing each other, the first protrusion 4 and the second The protrusion 5 is not provided. For this reason, in this stent 1, the diameter-restriction restricting portion after stent expansion formed by the first protrusion 4 and the second protrusion 5 is provided between every other annular body 2 facing each other. ing.
And the 1st protrusion part 4 and the 2nd protrusion part 5 are extended in the circumferential direction and different direction of the stent 1 (annular body 2). Specifically, as shown in FIGS. 1 to 3, the first projecting portion 4 of the annular body 2 a is located on the right side in the circumferential direction of the annular body and obliquely downward to the right so as to be close to the opposing annular body 2 b. It is an extension. Further, as shown in FIGS. 1 to 3, the second projecting portion 5 of the annular body 2 b extends diagonally to the left so as to be close to the circumferentially facing annular body 2 a in the left direction of the annular body. It has become. And in the stent 1 of this Example, the 1st protrusion part 4 and the 2nd protrusion part 5 are a thing of the substantially triangular shape extended in the circumferential direction and different direction of an annular body. For this reason, the 1st protrusion part 4 and the 2nd protrusion part 5 are narrow toward the front-end | tip, and also the front-end | tip part of the protrusion parts 4 and 5 has a rounded shape. .

Further, the first projecting portion 4 and the second projecting portion 5 extend in a separating direction before one projecting portion gets over the other projecting portion (the state shown in FIG. 3), and face each other after getting over. Engaging portions 42 and 52 that can be engaged are provided. Furthermore, the 1st protrusion part 4 and the 2nd protrusion part 5 have the inclined sides 41 and 51 for contacting and riding on at the time of expansion of a stent. The inclined side 41 of the first protrusion 4 and the inclined side 51 of the second protrusion 5 are inclined at a predetermined angle with respect to the central axis of the stent and are substantially parallel to each other.
Moreover, in this stent 1, the meshing part 42 of the 1st protrusion part 4 and the meshing part 52 of the 2nd protrusion part 5 are formed of the meshing inclination side for meshing after getting over. The meshing inclined side (meshing part) 42 of the first protrusion and the meshing inclined side (meshing part) 52 of the second protrusion are inclined with respect to the central axis of the stent and substantially parallel to each other. It has become.
Further, in the stent 1 of this embodiment, the other end side bent portion 22a provided with the first projecting portion 4 is connected by a linear portion, and one end located in the circumferential direction in which the first projecting portion 4 extends. The side bent portion 21b is an easily deformable bent portion. Similarly, the other-end-side bent portion 22b that is connected to the one-end-side bent portion 21a provided with the second protruding portion 5 by a linear portion and is positioned in the circumferential direction in which the second protruding portion 5 extends is also easy. It is a deformed bent part. The easily deformable portion bent portion is configured by making the width of the linear portion narrower than other bent portions. The other end side bent portion 22a provided with the first protruding portion 4 and the one end side bent portion 21a provided with the second protruding portion 5 are not easily deformable bent portions, Unexpected deformation of the first protrusion 4 and the second protrusion 5 is prevented.

Further, in the stent 1 of this embodiment, the other end side bent portion 22a provided with the first projecting portion 4 is connected by a linear portion, and one end located in the circumferential direction in which the first projecting portion 4 extends. The side bent portion 21b is connected to the one end side bent portion 21b by a linear portion, and the other end side bent portion 22b located in the circumferential direction in which the first protrusion 4 extends is an easily deformable bent portion. The annular body 2a having the first projecting portion 4 is an easily deformable linear portion formed by two easily deformable bent portions 21b and 22b and a linear portion connecting the two easily deformable bent portions 21b and 22b. 23.
Similarly, in the stent 1 of this embodiment, the one end side bent portion 21a provided with the second projecting portion 5 is connected to the linear portion, and the second projecting portion 5 extends in the circumferential direction. The end-side bent portion 22b is connected to the other-end-side bent portion 22b by a linear portion, and the one-end-side bent portion 21b located in the circumferential direction in which the second protrusion 5 extends is an easily deformable bent portion. The annular body 2b having the second projecting portion 5 is an easily deformable linear shape formed by a linear portion connecting the two easily deformable bent portions 22b and 21b and the two easily deformable bent portions 22b and 21b. Part 23.

In this stent 1, each of the annular body 2a having the first projecting portion 4 and the annular body 2b having the second projecting portion 5 has the above-described easily deformable linear portion 23, and the easily deformable line of the annular body 2a. The shaped part 23 is located on the projecting direction side of the first projecting part 4, and the easily deformable linear part 23 of the annular body 2 b is located on the projecting direction side of the second projecting part 5. For this reason, the easily deformable linear portion 23 of the annular body 2 a and the easily deformable linear portion 23 of the annular body 2 b extend in different directions in the circumferential direction of the stent 1.
For this reason, in this stent 1, the first projecting portion 4 of the annular body 2 a and the second projecting portion 5 of the annular body 2 b expand to the inclined sides 41 and 51 by expanding at the easily deformable portion 23 during expansion. And the expansion operation is continued, so that one projecting portion gets over the other projecting portion, and as shown in FIG. 7, the first projecting portion 4 of the annular body 2a and the second projecting portion of the annular body 2b. The protruding portion 5 is in a state of being meshed with the meshing inclined sides (meshing portions) 42 and 52. Further, when the expansion is continued, the meshing inclined sides (meshing portions) 42 and 52 are separated from each other, and the meshing state is canceled. However, since a force in the direction of reducing the inner diameter is applied to the expanded stent, the meshing inclined side (meshing portion) 42 of the first projecting portion 4 and the meshing tilt of the second projecting portion 5 are applied. The sides (meshing portions) 52 mesh with each other and suppress further reduction of the diameter of the stent.

  Moreover, as shown in FIG. 5, it is preferable that the end surfaces of the inclined sides 41 and 51 that come into contact when the first protruding portion 4 and the second protruding portion 5 get over are inclined surfaces. In the example shown in FIG. 5, the end surface of the inclined side 41 of the first projecting portion 4 has an inclined surface (inclined surface for getting on and guiding) 41 a inclined in the direction of the outer surface 1 a of the stent, and the second projecting portion. The end surface of the inclined side 51 of 5 has an inclined surface (inclined surface for carrying on) 51a inclined in the direction of the inner surface 1b of the stent. By having such inclined surfaces 41a and 51a, when the first protrusion 4 and the second protrusion 5 abut, the second protrusion 5 rides on the first protrusion 4. Therefore, it is easy to get over the other protrusion of one protrusion. In addition, the formation form of the inclined surfaces 41a and 51a may be reversed. Furthermore, as shown in FIG. 6, a climbing guide inclined surface 41 a is provided only on one of the inclined sides 41, 51 that come into contact with the first projecting portion 4 and the second projecting portion 5. Also good. In this case, as shown in FIG. 6, it is preferable to provide a slip-in guiding inclined surface on the outer surface side of one of the protrusions.

  In the stent 1 of this embodiment, the adjacent annular bodies 2 are connected by the connecting portion 3. The connecting portion 3 connects the other end side bent portion 22 of one adjacent annular body 2 and the one end side bent portion 21 of the other annular body 2. Moreover, the connection part 3 is arrange | positioned so that it may become spiral shape with respect to the axial direction of a stent. In addition, the post-stent expansion diameter-reducing restriction portion constituted by the first protrusion 4 and the second protrusion 5 described above is also spirally arranged in the axial direction of the stent. For this reason, as shown in FIG. 7, in a state where the first projecting portion 4 and the second projecting portion 5 are engaged with each other and the compression deformation regulating function is exhibited, the deformation regulating function exhibiting portion is also linear with respect to the axial direction of the stent. Therefore, the cured portion is dispersed, and as a whole, it has high compression resistance and does not have deformation directionality. Furthermore, in this stent 1, the diameter-restricting restricting portion after stent expansion (in other words, the first protruding portion 4 and the second protruding portion 5 facing each other) and the connecting portion 3 are substantially opposed to the central axis of the stent 1. It has a high compression deformation regulation function at the time of expansion of a stent by cooperation of both.

Moreover, as a form of the 1st protrusion part and 2nd protrusion part with which the stent of this invention is provided, the thing with which the stent 10 shown in FIG. 8 is provided may be sufficient.
The difference between the stent 10 of this embodiment and the above-described stent 1 is only in the form of the first protrusion and the second protrusion.
In the stent 10 of this embodiment, the first protrusion 14 has a large number of small protrusions 14 a extending in the same direction as the protrusion direction of the first protrusion 14, and the second protrusion 15 is also the second protrusion 15. It has many small protrusions 15a extending in the same direction as the protrusion direction of the protrusions 15. Therefore, the 1st protrusion part 14 and the 2nd protrusion part 15 become a sawtooth-shaped thing which can be engaged. In the stent 10 as well, when the stent is expanded, one projecting portion rides on the other projecting portion. However, in the stent 10 of this embodiment, as shown in FIG. 9, the small protrusion 14a and the small protrusion 15a engage each time one small protrusion is overcome when the stent is expanded. For this reason, even in a state where one protrusion does not completely cover the other protrusion, the small protrusion 14a of the first protrusion 14 and the small protrusion 15a of the second protrusion 15 mesh with each other. Easily exerts the function of restricting diameter reduction. In addition, in a state where the small protrusion 14a of the first protrusion 14 and the small protrusion 15a of the second protrusion 15 are engaged with each other, further expansion of the stent is performed, so that the small protrusion 14a and the small protrusion One of the portions 15a can be over the other. Similarly, even when the small protrusion 14a of the first protrusion 14 and the small protrusion 15a of the second protrusion 15 are engaged with each other, deformation of the stent in the expansion direction is not hindered.

Moreover, as a form of the 1st protrusion part and 2nd protrusion part with which the stent of this invention is provided, what the stent 20 shown in FIG. 10 is provided may be sufficient.
The difference between the stent 20 of this embodiment and the above-described stent 1 is only in the form of the first protrusion and the second protrusion.
In the stent 20 of this example, the protruding directions of the first protruding portion and the second protruding portion that form the diameter-reducing restriction portion after stent expansion are not all the same, The direction is different.
Specifically, in the stent 20, an annular body 2 a having a first protrusion 4 having the same form as the stent 1 of FIG. 1 and an annular body 2 b having a second protrusion 5 having the same form as the stent 1 are provided. An annular body 2a1 having a first projecting portion 4a projecting in a circumferential direction different from the first projecting portion 4 of the stent 1, and a second projecting projecting different from the second projecting portion 5 in the stent 1 It has what has the annular body 2b1 which has the part 5a. In this stent 20, the annular body 2a1, the annular body 2b1, the annular body 2a, and the annular body 2b are arranged in this order from one end side. For this reason, the protrusion directions of the first protrusion and the second protrusion that form the diameter-reducing restriction portion after stent expansion are alternately different.

The stent of the present invention may be a stent 30 of the type shown in FIG.
The basic configuration of the stent 30 of this embodiment is the same as the stent 1 described above. In this stent 30, each annular body has more than the stent 1, specifically, one end side bent portion 21 and the other end side bent portion 22 that are twice that of the stent 1. The adjacent annular bodies 2 are connected by two connecting portions 3. Further, in this stent 30, similarly to the above-described stent 1, the post-expansion reduced diameter regulating portion formed by the first projecting portion 4 and the second projecting portion 5 is provided between every other annular body 2 facing each other. Is provided. However, in this stent, two diameter-reducing restriction portions after stent expansion are provided between the annular bodies facing each other. Similar to the stent 1 described above, the diameter-reducing restriction portion after stent expansion is constituted by the first protrusion 4 and the second protrusion 5. The form of the 1st protrusion part 4 and the 2nd protrusion part 5 is the same as what was mentioned above.
And in this stent 30, many annular bodies 2c are repeated so that the order of the annular body 2c having two first protrusions 4 and the annular body 2d having two second protrusions 5 may be repeated from one end side. 2d are arranged in the axial direction. And also in the stent 30 of this Example, the 1st protrusion part 4 and the 2nd protrusion part 5 which comprise the connection part 3 and a stent expansion diameter-reducing regulation part are linear with respect to the axial direction of a stent ( Not parallel) but spirally. The two connecting portions 3 are arranged so as to be substantially opposed to the central axis of the stent. Similarly, the two diameter-reducing restriction portions after stent expansion are also arranged so as to be substantially opposed to the central axis of the stent. In the stent 30, the two post-expansion diameter-reducing restriction portions and the two connecting portions are arranged so as to be substantially equiangular with respect to the central axis of the stent.

The stent of the present invention may be a stent 40 of the type shown in FIG.
The basic configuration of the stent 40 of this embodiment is the same as the stent 1 described above. In the stent 40, each annular body has more one end side bent portions 21 and other end side bent portions 22 than the stent 1, specifically, twice the stent 1. The adjacent annular bodies 2 are connected by two connecting portions 3. The two connecting portions 3 are arranged so as to be substantially opposed to the central axis of the stent.
In this stent 30, unlike the stents 1 and 30 described above, the post-stent expansion diameter restricting portion formed by the first projecting portion 4 and the second projecting portion 5 is located between all the annular bodies 2 facing each other. Is provided. Specifically, in the stent 40, the annular body at one end is an annular body 2e having only the first protrusion 4 having the same form as the stent 1 of FIG. The second protrusion 5 having the same shape as that of the stent 1 is formed in an annular body 2g having only the second protrusion 5 having the same shape as that of the stent 1 and between the annular body 2e and the annular body 2g. A plurality of annular bodies 2f having both the first protrusions 4 having the same form as the stent 1 are arranged on the other end side. Since this stent 40 has a diameter-reducing restriction portion after stent expansion between all the annular bodies, the stent as a whole exhibits a high diameter-reducing restriction function.
In the stent 40 of this embodiment, as in the stent 20 described above, the protruding directions of the first protruding portion and the second protruding portion that form the diameter-reducing restriction portion after stent expansion are not all the same, and the shaft In the post-stent expansion diameter-reducing restriction portions adjacent to each other in the direction, the directions are different. Specifically, the annular body 2f includes a second projecting portion 5 having the same shape as the stent 1 on one end side, and the first projecting portion 4 of the stent 1 differs in the circumferential direction projecting from the first projecting portion 4 on the other end side. The first protrusion of the stent 1 is provided on the other end side of the type having the protrusion 4a and the second protrusion 5a having a different circumferential direction protruding from the second protrusion 5 of the stent 1 on one end side. The types having the first protrusions 4 having the same form as the portions 4 are alternately arranged.
And also in the stent 40 of this Example, the 1st protrusion part 4 and the 2nd protrusion part 5 which comprise the connection part 3 and a stent expansion diameter-reducing regulation part are linear with respect to the axial direction of a stent ( It is positioned to be spiral rather than parallel).

  In the stents of all the above-described embodiments, the outer diameter of the stent when not expanded (when the balloon is mounted) is preferably about 0.8 to 1.8 mm, and more preferably 0.9 to 1.4 mm. preferable. The length of the stent when it is not expanded (when the balloon is mounted) is preferably about 9 to 40 mm. Moreover, about 0.7-2.0 mm is suitable for the length of one wavy annular body. The number of peaks (in other words, the number of valleys) of one wavy annular body is preferably 4-12. Moreover, as a number of a wave-like annular body, 6-20 are suitable. Further, the outer diameter at the time of forming the stent (before mounting of the balloon) is preferably about 1.5 to 3.5 mm, and more preferably 2.0 to 3.0 mm. Furthermore, 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 portion is 0.07 to 0.15 mm. The degree is preferable, and 0.08 to 0.13 mm is particularly preferable.

As a material for forming the stent, a material having a certain degree of biocompatibility is preferable. For example, stainless steel, tantalum or tantalum alloy, platinum or platinum alloy, gold or gold alloy, cobalt nickel alloy, cobalt chromium 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. The chamfering method of the stent 1 can be performed by forming the stent into a final shape and then performing chemical polishing, electrolytic polishing or mechanical polishing.

  Furthermore, it is preferable to anneal after producing the final shape of the stent 1. By performing annealing, the force to restore the stent 1 to the shape before expansion after expansion, especially the force to return to the linear shape when expanded at the bent blood vessel site is reduced, and the bent blood vessel Physical stimulation applied to the inner wall is 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.

Next, the living organ dilator according to the present invention will be described with reference to embodiments shown in the drawings.
FIG. 13 is a front view of a living organ dilator according to an embodiment of the present invention. FIG. 14 is an enlarged partial cross-sectional view of the distal end portion of the biological organ dilator shown in FIG. FIG. 15 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 body 102, a foldable and expandable balloon 103 provided at the distal end of the shaft 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 stent 1 described above and 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. 14, 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. 14, 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, an outer diameter of 0.1 to 1.0 mm, more preferably 0.3 to 0.7 mm, and a wall thickness of The thickness is 10 to 250 μm, more preferably 20 to 100 μm. 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, an outer diameter of 0.5 to 1.5 mm, more preferably 0.7 to 1.1 mm, and a wall thickness of The thickness is 25 to 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 outer diameter of the rear end portion of the distal end side outer tube 113a and the main body side outer tube 113b is 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 rear end.
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. 14, 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. 15, 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 1.5 to 5.0 mm, preferably 2.0 to 4.5 mm, and the length is 5 to 5 mm. 50 mm, preferably 10 to 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 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.

Then, as shown in FIGS. 14 and 15, this living organ dilator 100 has two Xs fixed to the outer surface of the shaft main body at positions corresponding to both ends of the cylindrical portion (expandable portion) when expanded. Line contrast members 117 and 118 are provided. It should be noted that two X-ray contrast members fixed to the outer surface of the shaft main body portion 102 (in this embodiment, the inner tube 112) at positions that become both ends of the stent 1 may be provided. 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 contrasting 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. Examples of the forming material include gold, platinum, iridium, Tungsten or an alloy thereof, or a silver-palladium alloy is preferable.

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 a bent site such as a blood vessel without significantly reducing the flexibility of the living organ expanding device 100, and also provides the living organ expanding device. The pushing of the tip of 100 is facilitated. It is preferable that the tip of the rigidity imparting body has a smaller diameter than other parts by a method such as polishing. In addition, it is preferable that the distal end of the small diameter portion of the rigidity imparting body extends to the vicinity of the distal end portion of the main body outer tube 113. The rigidity imparting body is preferably a metal wire, particularly preferably an elastic metal wire such as stainless steel having a wire diameter of 0.05 to 1.50 mm, preferably 0.10 to 1.00 mm, and a superelastic alloy wire.

In the living organ dilator 100 of this embodiment, as shown in FIG. 13, a branch hub 110 is fixed to the rear 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.

DESCRIPTION OF SYMBOLS 1 Stent 2 Annular body 3 Connection part 4 1st protrusion part 5 2nd protrusion part

Claims (13)

A plurality of annular bodies formed annularly by linear components are arranged in the axial direction, and an indwelling stent in which adjacent annular bodies are connected by a connecting portion,
Each annular body has 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 one or a plurality of sets of adjacent annular bodies include a first protrusion provided at the other-end-side bent portion of the adjacent one of the adjacent annular bodies at the time of expansion, and the other adjacent annular body. A second projecting portion provided on the one-end-side bent portion, and the first projecting portion and the second projecting portion are able to get over when the stent is expanded, and after getting over the stent, A stent for indwelling in a living body, characterized in that a diameter-restricting portion after stent expansion that can contact when force is applied is formed. The in-vivo stent according to claim 1, wherein the first protrusion and the second protrusion extend in the circumferential direction of the annular body and in different directions. The one end side bent portion, which is connected to the other end side bent portion provided with the first protruding portion by a linear portion and is positioned in the circumferential direction in which the first protruding portion extends, is an easily deformable bent portion. The other end-side bent portion that is connected to the one-end-side bent portion provided with the second protruding portion by a linear portion and that is positioned in the circumferential direction in which the second protruding portion extends is easily deformable The in-vivo indwelling stent according to claim 2, which is a part. One end side bent portion that is connected to the other end side bent portion provided with the first protruding portion by a linear portion, and is positioned in the circumferential direction in which the first protruding portion extends, and the one end side bent portion The other end side bent portion connected by the linear portion and positioned in the circumferential direction in which the first protruding portion extends is an easily deformable bent portion, and the annular body having the first protruding portion is: The in-vivo indwelling stent according to claim 2 or 3, further comprising an easily deformable linear portion formed by the two easily deformable bent portions and a linear portion connecting the two easily deformable bent portions. The other end side bent portion, which is connected to the one end side bent portion provided with the second protruding portion by a linear portion and located in the circumferential direction in which the second protruding portion extends, and the other end side bent portion And the one end side bent portion located in the circumferential direction in which the second projecting portion extends is an easily deformable bent portion, and the annular body having the second projecting portion is The in vivo indwelling device according to any one of claims 2 to 4, further comprising an easily deformable linear portion formed by the two easily deformable bent portions and a linear portion connecting between the two easily deformable bent portions. Stent. The first projecting portion and the second projecting portion include a meshing portion that extends in a separating direction before getting over and extends in a direction in which the first projecting portion and the second projecting portion come close to each other after getting over and can mesh with each other. The stent for in-vivo placement according to any one of 5. The first protruding portion and the second protruding portion have inclined sides for contacting and riding on when the stent is expanded, and the inclined sides of the first protruding portion and the inclined sides of the second protruding portion The indwelling stent according to any one of claims 1 to 6, which is inclined and substantially parallel to the central axis of the stent. The meshing part of the first projecting part and the meshing part of the second projecting part have a meshing sloping side for meshing after getting over, and the meshing sloping side of the first projecting part and the second sloping side. The in-vivo indwelling stent according to any one of claims 1 to 7, wherein the meshing inclined side of the protruding portion is inclined and substantially parallel to the central axis of the stent. The living body according to any one of claims 2 to 8, wherein the first projecting portion and the second projecting portion have a substantially triangular shape extending in a circumferential direction and different directions of the annular body. Indwelling stent. The stent for in-vivo placement according to any one of claims 1 to 9, wherein the diameter-reducing restriction portion after stent expansion is provided in at least one pair of the annular bodies facing each other located in a central portion of the stent. The in-vivo indwelling stent according to any one of claims 1 to 10, wherein the diameter-reducing restriction portion after stent expansion is provided on the annular body facing each other at one end and the other end of the stent. The stent according to any one of claims 1 to 11, wherein the stent is formed into 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 is applied. The stent for in-vivo in any one of Claims. 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 12.

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