JP2009178228A - In vivo indwelling stent and biological organ dilator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an in vivo indwelling stent having flexibility between respective annular members in the indwelling form of the stent in vivo, preventing the large movement of the stent caused by the separation of the respective annular members adjacent to each other in the axial direction of the stent and capable of well and succeedingly improving the constricted part of a target region in which the stent is arranged. <P>SOLUTION: The in vivo indwelling stent 1 is composed of large number of isolated annular members 2 each of which is formed into an annular shape by a linear constituent element and which are arranged in the axial direction of the stent, and a joint mechanism 3 for connecting the adjacent annular members 2 in the indwelling form of the stent in vivo so as to make them non-separable but slightly movable in the axial direction of the stent is provided between the annular members 2 adjacent in the axial direction of the stent. <P>COPYRIGHT: (C)2009,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.
The purpose of stent placement is to prevent and reduce restenosis that occurs after a procedure such as PTCA. And in recent years, a bioactive substance is carried on the stent so that the bioactive substance can be locally released over a long period of time at the indwelling site of the lumen to reduce the restenosis rate. .

For example, Japanese Patent Application Publication No. 2004-516885 (Patent Document 1) discloses a radially expandable cylindrical ring that is aligned on a common axis and interconnected by one or more links. And at least some of the links are formed of a polymeric material and provide sufficient longitudinal and bending flexibility to the stent, while at the same time sufficient to separate the rings along the longitudinal axis. A stent that maintains column strength is disclosed.
JP 2005-501654 (Patent Document 2) discloses an expandable stent including a tubular body composed of a number of separate tubular elements (1) aligned along a common longitudinal axis. The tubular element (1) comprises a number of diamond-shaped occlusion cell elements (2) connected by a peripherally extending connecting member (3), allowing the tubular element and hence the stent itself to expand. Thus, the occluded cell elements (2) are expandable, and in the longitudinal axis of the stent, there is an enlarged loop (30) with a constricted portion (33) at the tip of each occluded cell element, thereby Tubular elements are disclosed that are interlocked to create a stable structure, at least when in an unexpanded state.

JP-T-2004-516885 JP 2005-501654 A

In Patent Document 1, the radially expandable cylindrical rings are connected by a link formed of a polymer material. For this reason, the space between the cylindrical rings is more flexible than that in which all the links are made of metal. However, since the cylindrical rings are connected so as not to be separated by the links, the adjacent cylindrical rings are also affected by one of the deformations, and the flexibility between them is not sufficient.
In Patent Document 2, a large number of separated tubular elements are interlocked in a state where they are arranged on a balloon, but the interlock between the large number of separated tubular elements is released by stretching. . For this reason, each tubular element can be individually deformed and the flexibility between the annular elements is good. However, since the individual annular 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 region cannot be continuously expanded.

  An object of the present invention is a stent formed of a plurality of isolated annular bodies formed in an annular shape by linear components and arranged in the axial direction of the stent, and in the indwelling form of the stent, In-vivo indwelling stent that has flexibility between annular bodies, prevents large movements between the annular bodies adjacent in the axial direction, and can continuously improve the narrowed portion of the target site disposed therein. A biological organ dilator is provided.

What achieves the above object is as follows.
(1) A stent for in-vivo indwelling that adheres to in-vivo tissue by being deformed during in-dwelling operation,
The stent is formed of a plurality of isolated annular bodies formed in an annular shape by linear components and arranged in the axial direction of the stent, and further, between each annular body adjacent in the axial direction. In the indwelling form of the stent in the living body, a joint mechanism for connecting the stent in the axial direction is provided, and the joint mechanism includes a first joint portion having a locking portion, and the annular body. A stent for indwelling in vivo, comprising a second joint portion that engages with the locking portion when the stent moves in the axial direction.

(2) The in-vivo indwelling stent according to (1), wherein the joint mechanism is configured to connect the adjacent annular bodies so as not to be detached in an indwelling form of the stent.
(3) The locking portion is a bulging portion, and the second joint portion accommodates the bulging portion and engages with the bulging portion when the annular body moves in the axial direction of the stent. The stent for in-vivo placement according to the above (1) or (2), which prevents the withdrawal.
(4) The in-vivo stent according to any one of (1) to (3), wherein the joint mechanism includes three or more joint portions formed between adjacent annular bodies.
(5) The in-vivo stent according to any one of (1) to (4), wherein the joint mechanism substantially prevents twisting of adjacent annular bodies in the circumferential direction.

(6) Any of the above (1) to (5), wherein the adjacent annular bodies include adjacent bent vertex portions, and the joint mechanism is formed between adjacent bent vertex portions of adjacent annular bodies. The stent for in-vivo indwelling.
(7) The two adjacent annular bodies each have a linear portion extending in the direction of the other annular body, and the joint mechanism is formed between the opposing end portions of the linear portion. (5) The stent for in-vivo indwelling in any one of.
(8) Each of the annular bodies includes an endless first wavy annular body that is annularly continuous, and a second that is arranged in an axial direction so that a peak portion is close to a trough of the first wavy annular body. Said (1) thru | or which has a corrugated annular body and at least 1 junction part which connects the said peak part of the said 2nd corrugated annular body which adjoins the said trough part of a said 1st corrugated annular body. (7) The in-vivo indwelling stent according to any one of (7).
(9) Each of the annular bodies is an annular body in which linear ring portions that are long in the axial direction of the stent are arranged so as to surround the central axis of the plurality of stents, and adjacent linear ring portions are connected at a joint portion. The stent for in-vivo placement in any one of said (1) thru | or (7) which consists of.

(10) Any of the above (1) to (7), wherein each of the annular bodies is a wavy annular body having a plurality of one-end bending apexes of the stent and a plurality of the other-end bending apexes of the stent. The stent for in-vivo indwelling.
(11) 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 (10) above.
(12) The stent according to (1) to (1), 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 the shape before compression. (10) The indwelling stent according to any one of (10).

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 (11), which is expanded by expansion.
(14) A sheath, the stent of (12) housed in the distal end portion of the sheath, and an inner tube for slidably inserting the sheath and discharging the stent from the distal end of the sheath A living organ expansion device provided.

The stent for in-vivo indwelling of the present invention is in close contact with the in-vivo tissue by being deformed during in-dwelling operation. The stent is formed of a plurality of isolated annular bodies formed in an annular shape by linear components and arranged in the axial direction of the stent. Further, between the annular bodies adjacent in the axial direction, In the indwelling form of the stent in the living body, a joint mechanism for connecting the stent in the axial direction is provided, and the joint mechanism includes a first joint portion having a locking portion and an axial direction of the annular stent. And a second joint portion that engages with the locking portion when moved to the position.
For this reason, in this stent, in the indwelling form of the stent, in other words, since each annular body is isolated when placed in the living body, the first joint portion is in the axial direction of the stent. And the second joint part can be slightly moved until they are engaged, and can move individually in other directions (for example, the direction perpendicular to the axis of the stent). The deformability between them is good, and the entire stent has good flexibility. Furthermore, since changes in one annular body are rarely transmitted to adjacent annular bodies, the adjacent annular bodies have individual deformability, and each annular body is affected by the adjacent annular bodies. It exhibits good vasodilator power without any problems. Moreover, since the adjacent annular bodies are not integrated, damage due to fatigue is less likely to occur compared to an integrated connector.

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 developed view of the in-vivo indwelling stent of FIG. 1 when it is expanded. FIG. 4 is a partially enlarged view of FIG. FIG. 5 is a partially enlarged perspective view of FIG. FIG. 6 is a partially enlarged view of an in-vivo stent according to another embodiment of the present invention.

  The in vivo indwelling stent 1 of the present invention is a stent that adheres to an in vivo tissue by being deformed during the indwelling operation. The stent 1 is formed of a plurality of isolated annular bodies 2 formed in an annular shape by linear components and arranged in the axial direction of the stent 1, and further, between the annular bodies 2 adjacent in the axial direction. In the indwelling form of the stent in the living body, a joint mechanism 3 is provided for connecting the stent so as to be movable in the axial direction. The joint mechanism 3 includes a first joint portion 31 having a locking portion 33 and a second joint portion 32 that engages with the locking portion when the annular body 2 moves in the axial direction of the stent.

The in vivo indwelling stent 1 of the present invention is a stent that adheres to an in vivo tissue by being deformed during the indwelling operation. The stent 1 is formed of a plurality of isolated annular bodies 2 formed in an annular shape by linear components and arranged in the axial direction of the stent, and further, between each annular body 2 adjacent in the axial direction. In the indwelling form of the stent, a joint mechanism 3 is provided that connects the adjacent annular bodies 2 so that they cannot be detached and can be slightly moved (separated and approached) in the axial direction of the stent.
The stent 1 of this embodiment is a stent that 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 that extends radially from the inside of the tubular body is applied. Yes, a so-called balloon expandable stent. The stent of the present invention is not limited to such a balloon expandable stent, and may be a self-expandable stent.

And in the stent 1 of this Example, the annular body 2 includes a plurality of peak portions (one end side bent portion) 81 located on one end side of the stent and a plurality of valley portions (other end side bent portion) located on the other end side. ) 82, a plurality of peaks (one end side bent portion) 91 located on one end side of the stent, and a plurality of valleys (other end side bent portion) located on the other end side. The second wavy annular body 9 having 92, and the joint portion 5 that connects the first wavy annular body 8 and the second wavy annular body 9.
Specifically, the second corrugated annular body 9 is arranged in the axial direction of the stent 1 so that the peak portion 91 is close to the trough portion 82 of the first corrugated annular body 8, and the adjacent first corrugated annular body 9 is arranged. The trough portion 82 of the annular body 8 and the peak portion 91 of the second wavy annular body 9 are connected by the short joint portion 5 to form an integrated annular body 2. In the stent 1, a plurality of annular bodies 2 are linearly arranged in the axial direction of the stent 1, and adjacent annular bodies 2 are connected by a joint mechanism 3.

  The corrugated annular body in the stent 1 of this embodiment has an endless corrugated body having a plurality of crests and troughs with substantially the same pitch as shown in FIG. It is comprised by. In addition, 4-10 are suitable for the number of the peaks (or valleys) of the wavy annular body. In the stent 1 of this embodiment, a plurality of (specifically, two) joint portions 5 are provided between the first wavy annular body 8 and the second wavy annular body 9. In addition, although it is preferable to provide two or more joining parts 5 between the 1st wavy annular body 8 and the 2nd wavy annular body 9, you may provide only one. Furthermore, all the trough portions 82 of the first wavy annular body 8 and all the crest portions 91 of the second wavy annular body 9 may be connected by the joint portion 5.

  The stent according to the present invention is arranged in the axial direction of the stent such that the peak portion is close to the first wavy annular body and the valley portion of the first wavy annular body as in the stent 1 described above. The second wavy annular body formed in a ring shape by the corrugated elements, and the joint formed by connecting the valley portion of the first wavy annular body and the crest portion of the second wavy annular body. It is not something.

  In the stent 1 of this embodiment, the adjacent annular bodies 2 are adjacent bent portions (specifically, the valley portion 92 of the second wavy annular body 9 and the peak portion 81 of the first wavy annular body 8. ), And the joint mechanism 3 is between the adjacent bent portions of adjacent annular bodies (specifically, between the valley portion 92 of the second wavy annular body 9 and the crest portion 81 of the first wavy annular body 8). Is formed.

  Furthermore, in this stent 1, the joint mechanism 3 is constituted by three or more joint portions 30 formed between adjacent annular bodies. In the indwelling form of the stent, when one of the adjacent annular bodies is moved in a direction perpendicular to the central axis of the stent, the stent can be moved slightly in the axial direction and moved by a predetermined amount. Then, since any one of the joint portions 30 comes into contact, the joint mechanism connects the adjacent annular bodies so as not to be detached. Further, the joint mechanism is configured such that when the adjacent annular bodies are twisted in one circumferential direction, the joint portion 30 comes into contact, and substantially prevents the adjacent annular bodies from being twisted. ing.

  In particular, in the stent 1, one of the adjacent annular bodies is moved in a direction orthogonal to the central axis of the stent even during compression (in other words, when attached to the living organ dilator) shown in FIGS. 1 and 2. In some cases, the stent can be slightly moved in the axial direction, and when it moves a predetermined amount, one of the joint portions 30 comes into contact, so the joint mechanism connects the adjacent annular bodies so as not to be detached. Further, the joint mechanism is configured such that when the adjacent annular bodies are twisted in one circumferential direction, the joint portion 30 comes into contact, and substantially prevents the adjacent annular bodies from being twisted. ing.

  And it is preferable that each joint part 30 is provided so that it may become substantially equiangular arrangement with respect to the center axis | shaft of a stent. That is, in the stent 1 of this embodiment, the three joint portions are arranged at intervals of about 120 degrees. Further, four or more joint portions may be provided, and also in this case, each joint portion is preferably provided so as to be arranged at substantially equal angles with respect to the central axis of the stent. In addition, it is preferable that each joint part 30 is provided so that it may become substantially equiangular arrangement | positioning with respect to the center axis | shaft of a stent, However, It comprises three or more joint parts, and at least 2 of them is the center of a stent. It is good also as what does not face an axis.

And in the stent 1 of this Example, as shown in FIG.4 and FIG.5, the joint part 30 accommodates the 1st joint part 31 which has the bulging part 33 which is a latching part, and the bulging part 33. As shown in FIG. In addition, the annular body 2 is configured by a second joint portion 32 that engages with the bulging portion 33 and prevents detachment when the stent 1 moves in the axial direction.
Specifically, the first joint portion 31 is a linear portion extending in the other end direction of the stent from the valley portion 92 of the second wavy annular body 9 constituting the annular body 2, and a bulging portion is formed at the distal end portion thereof. (Locking portion) 33 is formed. Specifically, the first joint portion 31 includes a linear portion 37 and a bulging portion 33 formed at the tip portion thereof. The bulging portion 33 is a part of the first joint portion 31 and is wider than the linear portion 37.

  The second joint portion 32 is formed at the peak portion 81 of the first wavy annular body 8 constituting the annular body 2. The second joint portion 32 is positioned at the lower portion of the notch portion 81a through which the linear portion 37 of the first joint portion 31 is slidably inserted, and accommodates the locking portion (bulging portion) 33. A storage portion 81b is provided. The width of the opening of the storage part 81 b (in other words, the width of the cutout part 81 a) is slightly smaller than the width of the bulging part 33. For this reason, when the two adjacent annular bodies 2 move in a direction away from each other in the axial direction of the stent 1, the bulging portion 33 and the cutout portion 81 a (opening portion of the storage portion 81 b) engage with each other. Prevent withdrawal. And the 2nd joint part is provided with the partition part 81c which divides the storage part 81b, and the storage part 81b is a part enclosed by the vertex of the peak part 81 and this partition part. Since there is a slight gap between the bulging portion 33 and the partitioning portion 81c, the adjacent two annular bodies 2 can be slightly moved in the axial direction of the stent.

  And in the stent 1 of this Example, as shown in FIG.4 and FIG.5, the latching | locking part (bulging part) 33 and the accommodating part 81b become a substantially rectangular thing. Both shapes are not limited to the above. For example, the locking part and the storage part may be substantially circular. Further, the locking portion and the storage portion are not limited to the rectangular shape and the circular shape described above, but may be a polygonal shape or an elliptical shape. Different things, for example, a bulging part may be circular, an ellipse, and a polygon, and a storage part may be a rectangular shape. Moreover, the form of a 1st joint part and a 2nd joint part may be reverse.

Further, as shown in FIG. 5, the first joint portion 31 and the second joint portion 32 constituting the joint portion 30 have a predetermined thickness, so that the adjacent annular bodies are somewhat in a direction perpendicular to the axis of the stent. Even if it moves, both will not leave.
Furthermore, the stent 1 of this embodiment is provided with a concave portion 81d for suppressing deformation of the joint portion 30 when the stent is expanded. In particular, in the stent 1 of this embodiment, two concave portions 81d are provided so as to face the side portion of the partition portion of the second joint portion 32. For this reason, even if it deform | transforms into the state opened between the two linear parts 8a and 8a following the partition part 81c at the time of expansion of a stent, the joint part 30 does not deform | transform substantially but maintains the state mentioned above. . In addition, although it is preferable to provide the above recessed part, you may not have a recessed part like the joint part 30a in the stent 1a shown in FIG.

Further, the stent of the present invention may be a stent 10 as shown in FIG. FIG. 7 is a developed view of the in-vivo stent according to another embodiment of the present invention.
The stent 10 of this embodiment is a stent that 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. Yes, a so-called balloon expandable stent.
In the stent 10 of this embodiment, each annular body is a wavy annular body having a plurality of one-end-side bent apex portions and a plurality of other-end-side bent apex portions.

As shown in FIG. 7, the annular body 12 in the stent 10 of this embodiment has a plurality of crests (one-end-side bending vertex) and valleys (other-end-side bending vertex) having substantially the same pitch. It is an endless wavy body continuous. In addition, 4-10 are suitable for the number of the peaks (or valleys) of the wavy annular body.
And in the stent 10 of this Example, the adjacent annular body 12 is equipped with the adjacent bending part (specifically, the trough part 14 and the peak part 13 of an adjacent annular body), and the joint mechanism 3 is adjacent. It is formed between the adjacent bent portions of the annular body (specifically, between the valley portion 14 and the mountain portion 13 of the adjacent annular body).

  Further, in this stent 10, the joint mechanism 3 is constituted by three or more joint portions 30 formed between adjacent annular bodies. For this reason, when one of the adjacent annular bodies is moved in a direction perpendicular to the central axis of the stent, one of the joint portions 30 abuts, so that the joint mechanism connects the adjacent annular bodies so as not to be detached. . The joint portions 30 are preferably provided so as to be arranged at substantially equal angles with respect to the central axis of the stent. That is, in the stent 10 of this embodiment, the three joint portions are arranged at intervals of about 120 degrees. Further, four or more joint portions may be provided, and also in this case, each joint portion is preferably provided so as to be arranged at substantially equal angles with respect to the central axis of the stent. In addition, it is preferable that each joint part 30 is provided so that it may become substantially equiangular arrangement | positioning with respect to the center axis | shaft of a stent, However, It comprises three or more joint parts, and at least 2 of them is the center of a stent. It is good also as what does not face an axis. And the structure of the joint mechanism in the stent 10 of this Example is the same as that of the stent 1 mentioned above.

Further, the stent of the present invention may be a stent 20 as shown in FIGS. FIG. 8 is a developed view of the in-vivo stent according to another embodiment of the present invention. FIG. 9 is a partially enlarged view of FIG.
In this stent 20, each annular body 2 is arranged so that linear ring portions 4 that are long in the axial direction of the stent 20 surround the central axis of the plurality of stents 20, and adjacent linear ring portions 4 are joined portions 6. It is connected with.

  In the stent 20 of this embodiment, the annular body 2 includes a linear ring portion 4 and a joint portion 6 that connects the side portions of the linear ring portion 4. Specifically, the annular body 2 has a configuration in which linear ring portions 4 that are long in the axial direction of the stent 20 are provided in the circumferential direction of the plurality of stents, and these are joined at the side portions by the joint portion 6. The linear ring portion 4 has a substantially rhombus shape, and includes two circumferential corner portions 43 and 44 facing the circumferential direction of the stent 20, and two axial corner portions 41 and 42 facing the axial direction of the stent 20. Four diagonal lines are provided to connect the four corners 41, 42, 43, 44. And the junction part 6 has connected the circumferential direction corner | angular part 43 of the one adjacent linear ring part, and the circumferential direction corner | angular part 44 of the other linear ring part. Moreover, 4-10 are suitable for the number of the linear ring parts 4 in the one annular body 2. 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. 8, the stent 20 includes a joint mechanism 3 that connects a plurality of annular bodies 2 so that the annular bodies 2 are arranged substantially linearly in the axial direction of the stent 20. Yes.
And in the stent 20 of this Example, as shown to FIG. 8 and FIG. 9, both adjacent annular bodies have the linear parts 34 and 35 extended in the other annular body direction, It is formed between the opposite ends of the linear portions 34 and 35.
Specifically, as shown in FIGS. 8 and 9, the stent 20 includes a plurality of annular bodies 2 arranged in a substantially linear shape in the axial direction of the stent 20, and the adjacent annular bodies 2. A joint mechanism 3 for connecting the joints 6 is provided. And the joint mechanism is comprised by the some joint part 30b. Moreover, in the stent 20 of this Example, the joint mechanism 3 is located in the intermediate part of the adjacent annular body 2. As shown in FIG.

  As shown in FIG. 9, the stent 20 includes a first linear portion 34 extending in the axial direction of the stent toward the annular body 2 on the other end side adjacent to the annular body 2 on the one end side, and an annular body on the other end side. 2 is provided with a second linear portion 35 extending in the axial direction of the stent toward the annular body 2 on the one end side. And the free end part of the 1st linear part 34 and the free end part of the 2nd linear part 35 are adjoining. Further, as shown in FIG. 9, a first joint portion 31 b having a bulging portion 33 b is formed at the free end portion of the first linear portion 34, and the free end portion of the second linear portion 35 is formed. Is formed with a second joint portion 32b that accommodates the bulging portion 33b and engages with the bulging portion 33b to prevent separation when the stent 20 of the annular body 2 moves in the axial direction. The bulging part 33b is a part of the linear part that forms the first joint part 31b, and is a part having a larger width than the other part. The second joint portion 32 b is configured by a notch portion and a storage portion formed at the free end portion of the second linear portion 35. The second joint portion 32b includes a storage portion 81b that stores the bulging portion 33b of the first joint portion 31b, and a cutout portion 81a that is located at the upper portion of the storage portion and restricts the detachment of the bulging portion 33b. And the width | variety of the opening part of the notch part 81a is a little smaller than the width | variety of the bulging part 33b. For this reason, when the two adjacent annular bodies 2 move in a direction away from each other in the axial direction of the stent 20, the bulging portion 33 b and the opening of the notch portion 81 a engage with each other, thereby preventing the detachment of both. . And in the stent 20 of this Example, the bulging part 33b and the accommodating part 81b are circular. Both shapes are not limited to the above. The bulging portion and the storage portion that form the joint portion are not limited to the circular shape described above, and may be rectangular, polygonal, or elliptical. The shape may be different, for example, the bulging portion may be circular, elliptical, or polygonal, and the storage portion may be rectangular. Moreover, the form of a 1st joint part and a 2nd joint part may be reverse.

Further, the stent of the present invention may be a stent 40 as shown in FIGS.
FIG. 10 is a front view of an in-vivo stent according to another embodiment of the present invention. FIG. 11 is a developed view of the in-vivo stent of FIG. FIG. 12 is a partially enlarged view of FIG.
The stent 40 of this embodiment is a stent that 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. Yes, a so-called balloon expandable stent.

In the stent 40 of this embodiment, the annular body 12 includes a plurality of peaks (one end side bent portion) 13 located on one end side of the stent and a plurality of valleys (other end side bent portion) located on the other end side. ) 14.
As shown in FIGS. 10 and 11, the annular body 12 in the stent 40 of this embodiment is an endless corrugated body having a plurality of crests and troughs with substantially the same pitch, and being annularly continuous. In addition, 4-10 are suitable for the number of the peaks (or valleys) of the wavy annular body.

As shown in FIGS. 10 and 11, in the stent 40, the plurality of annular bodies 12 are arranged so as to be substantially linear in the axial direction of the stent 40, and the joint mechanism 3 that connects adjacent annular bodies 12. It has. In particular, the stent 40 of this embodiment is connected by the joint mechanism 3 formed between the bent portions of the adjacent annular bodies (specifically, between the crests 13 of the adjacent annular bodies).
As shown in FIGS. 10 and 11, the stent 40 has a plurality of annular bodies 12 arranged so as to be substantially linear in the axial direction of the stent 40, and a joint mechanism that connects adjacent annular bodies 12. 3 is provided. The joint mechanism 3 includes three joint portions 30c as in the above-described embodiment.

  As shown in FIGS. 10 to 12, the stent 40 has a linear portion extending in the axial direction of the stent from the crest portion 13 of the annular body 12 on one end side toward the crest portion 13 of the annular body 12 on the other end side. 36. The crest portion 13 of the annular body 12 on the other end side adjacent to the free end portion of the linear portion 36 is close. And as shown in FIG. 12, the 1st joint part 31c is formed in the free end part of the linear part 36, and the 2nd joint part 32c is formed in the peak part 13 of the annular body 12 of the other end side. Is formed. The joint portion 30c accommodates the first joint portion 31c having the bulging portion 33, and the bulging portion 33, and engages with the bulging portion 33 when the annular body 12 moves in the axial direction of the stent 40, thereby preventing separation. And the second joint portion 32c. The bulging part 33 is a part of the linear part which forms the 1st joint part 31c, and is a part with a larger width | variety than another part. The second joint portion 32 c is configured by a cutout portion formed in the peak portion 13 of the annular body 12 and a storage portion. The second joint portion 32c includes a storage portion 81b that stores the bulging portion 33 of the first joint portion 31c, and a cutout portion 81a that is located at the upper portion of the storage portion and restricts the detachment of the bulging portion 33. The width of the opening of the notch 81 a is slightly smaller than the width of the bulging portion 33. For this reason, when the two adjacent annular bodies 12 move in the direction away from each other in the axial direction of the stent 40, the bulging portion 33 and the opening of the notch portion 81a are engaged with each other, thereby preventing the detachment of both. . And in the stent 40 of this Example, the bulging part 33 and the accommodating part 81b are a rectangular thing. Both shapes are not limited to the above. For example, like the joint part 30b shown in FIG. 9, a 1st joint part may be provided with a substantially circular bulging part, and a 2nd joint part may have a circular accommodating part. Furthermore, the bulging part and the storage part that form the joint part are not limited to the rectangular shape or the circular shape described above, but may be a polygon or an ellipse. The shape may be different, for example, the bulging portion may be circular, elliptical, or polygonal, and the storage portion may be rectangular. Moreover, the form of a 1st joint part and a 2nd joint part may be reverse.

  And in this stent 40, the joint mechanism 3 is comprised by the three or more joint parts 30c formed between the adjacent annular bodies. For this reason, when one of the adjacent annular bodies is moved in a direction orthogonal to the central axis of the stent, one of the joint portions 30c comes into contact, so that the joint mechanism connects the adjacent annular bodies so as not to be detached. . The joint portions 30c are preferably provided so as to be arranged at substantially equal angles with respect to the central axis of the stent. That is, in the stent 40 of this embodiment, the three joint portions are arranged at intervals of about 120 degrees. Further, four or more joint portions may be provided, and also in this case, each joint portion is preferably provided so as to be arranged at substantially equal angles with respect to the central axis of the stent. In addition, it is preferable that each joint part 30c is provided so that it may become substantially equiangular arrangement | positioning with respect to the center axis | shaft of a stent, However, It comprises three or more joint parts, and at least 2 of them is the center of a stent. It is good also as what does not face an axis.

In all the embodiments described above, the joint mechanism may be the joint mechanism 3a included in the stent 50 shown in FIGS.
FIG. 13 is a developed view of the in-vivo stent according to another embodiment of the present invention. FIG. 14 is a partially enlarged view of FIG.
In the stent 50 of this embodiment, the joint mechanism 3a includes a plurality of joint portions as in the above-described embodiment.

The joint mechanism 3a includes three or more joint portions, one of which is different in form from the other two.
Specifically, as shown in FIG. 14, the first form joint portion 53 a extends from the valley portion 92 of the second wavy annular body 9 constituting the annular body 2 toward the other end of the stent, and the distal end portion is first. The first joint portion 54 having a first locking portion bent in the circumferential direction of 1 and the peak portion 81 of the first wavy annular body 8 constituting the annular body 2 extend in the one end direction of the stent and the distal end portion is first. It is comprised by the 2nd joint part 55 which has the 2nd latching | locking part bent in the 2nd circumferential direction opposite to 1 circumferential direction. As shown in FIG. 14, the first locking portion of the first joint portion 54 and the second locking portion of the second joint portion 55 are in a meshed state. When two adjacent annular bodies 2 move in a direction away from each other in the axial direction of the stent 50, the first locking portion of the first joint portion 54 and the second locking portion of the second joint portion 55 are engaged. This prevents the two from leaving.

And the 2nd form joint part 53b is extended in the other end direction of a stent from the trough part 92 of the 2nd wavy annular body 9 which comprises the annular body 2, and the front-end | tip part is the above-mentioned 2nd as shown in FIG. The third joint portion 56 having a third locking portion bent in the circumferential direction and the peak portion 81 of the first wavy annular body 8 constituting the annular body 2 extend in the one end direction of the stent, and the distal end portion is the above-described portion. The fourth joint portion 57 has a fourth locking portion bent in the first circumferential direction.
And as shown in FIG. 14, the 3rd latching | locking part of the 3rd joint part 56 and the 4th latching | locking part of the 4th joint part 57 are the states which meshed | engaged. That is, the 2nd form joint part 53b becomes a form which reversed the 1st form joint part 53a. For this reason, when the force which rotates in the 1st circumferential direction mentioned above is given to one of the adjacent annular bodies 2, the 1st latching | locking part of the 1st joint part 54 in the 1st form joint part 53a, and 2nd. Engagement of the second locking portion of the joint portion 55 prevents rotation between the two and separation by rotation. Moreover, when the force which rotates in the 2nd circumferential direction mentioned above is provided to one of the adjacent annular bodies 2, the 3rd latching | locking part of the 3rd joint part 56 in the 2nd form joint part 53b, and a 6th joint Engagement of the fourth locking portion of the portion 57 prevents rotation (twist) between the two and separation by rotation.

  In all the above-described stents, the stent preferably has a non-expanded diameter of about 0.8 to 1.8 mm, and more preferably 0.9 to 1.4 mm. The length of the stent when not expanded is preferably about 9 to 40 mm. Further, the length of one wave-like annular body is preferably about 0.7 to 2.0 mm, and the length of one annular body is preferably about 1.5 to 4.0 mm. 0.0-3.0 mm is more preferable. Further, the number of peaks (in other words, the number of valleys) of one wavy annular body is preferably 4-8, and particularly preferably 5-7. Moreover, as a number of annular bodies, 4-15 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. 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 wavy element is about 0.07 to 0.15 mm. Is preferable, and 0.08 to 0.13 mm is particularly preferable.

As a material for forming a stent, a material having a certain degree of biocompatibility is preferable. 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.

Next, the living organ dilator according to the present invention will be described with reference to embodiments shown in the drawings.
FIG. 15 is a front view of a living organ dilator according to an embodiment of the present invention. FIG. 16 is an enlarged partial cross-sectional view of the distal end portion of the living organ dilator shown in FIG. FIG. 17 is an explanatory diagram for explaining the operation of the living organ dilator according to the embodiment of the present invention.
The vasodilator 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 vasodilator 100 according to this embodiment includes the above-described stent 1 and a tube-shaped biological organ dilator 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. 16, 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. 16, 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. 16, 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. 17, 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. 16 and 17, the vasodilator 100 has two X-rays fixed to the outer surface of the shaft main body at the positions corresponding to both ends of the cylindrical portion (expandable portion) when expanded. 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. 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, 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. 15, 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.

The stent according to the present invention is a so-called self-expanding stent that 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. It may be. Even in this case, the forms of all the embodiments described above can be used as the form of the stent.
When the stent is a self-expanding stent, a superelastic metal is suitable as a material for forming the stent. 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.

FIG. 18 is a partially omitted front view of a living organ dilator according to another embodiment of the present invention. FIG. 19 is an enlarged longitudinal sectional view of the vicinity of the distal end portion of the biological 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. 18, the living organ expanding device 200 of this embodiment includes a sheath 202, a self-expanding stent 201, and an inner tube 204.
As shown in FIGS. 18 and 19, 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. 18 and 19, 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 distal end portion 247 is preferably formed in a tapered shape that protrudes from the distal end of the sheath 202 and gradually decreases in diameter toward the distal end 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 that 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. 19, the inner tube 204 includes two projecting portions 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. 19, the inner tube 204 has a lumen 241 extending from the distal end to at least the proximal end side of the stent accommodating 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 accommodating 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. 18, 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 developed view of the in-vivo indwelling stent of FIG. 1 when it is expanded. FIG. 4 is a partially enlarged view of FIG. FIG. 5 is a partially enlarged perspective view of FIG. FIG. 6 is a partially enlarged view of an in-vivo stent 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 partially enlarged view of FIG. FIG. 10 is a front view of an in-vivo stent according to another embodiment of the present invention. FIG. 11 is a developed view of the in-vivo stent of FIG. FIG. 12 is a partially enlarged view of FIG. FIG. 13 is a developed view of the in-vivo stent according to another embodiment of the present invention. FIG. 14 is a partially enlarged view of FIG. FIG. 15 is a front view of a living organ dilator according to an embodiment of the present invention. FIG. 16 is an enlarged partial cross-sectional view of the distal end portion of the living organ dilator shown in FIG. FIG. 17 is an explanatory diagram for explaining the operation of the living organ dilator according to the embodiment of the present invention. FIG. 18 is a partially omitted front view of a living organ dilator according to another embodiment of the present invention. FIG. 19 is an enlarged longitudinal sectional view of the vicinity of the distal end portion of the biological organ dilator shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Stent for in-vivo placement 2 Ring body 3 Joint mechanism

Claims (14)

A stent for in-vivo indwelling that adheres to in-vivo tissue by being deformed during in-dwelling operation,
The stent is formed of a plurality of isolated annular bodies formed in an annular shape by linear components and arranged in the axial direction of the stent, and further, between each annular body adjacent in the axial direction. In the indwelling form of the stent in the living body, a joint mechanism for connecting the stent in the axial direction is provided, and the joint mechanism includes a first joint portion having a locking portion, and the annular body. A stent for indwelling in vivo, comprising: a second joint portion that engages with the locking portion when the stent moves in the axial direction. The in-vivo indwelling stent according to claim 1, wherein the joint mechanism connects the adjacent annular bodies so as not to be detached when the stent is in-vivo. The locking portion is a bulging portion, and the second joint portion accommodates the bulging portion and engages and disengages with the bulging portion when the annular body moves in the axial direction of the stent. The stent for in-vivo indwelling according to claim 1 or 2 which stops. The in-vivo stent according to any one of claims 1 to 3, wherein the joint mechanism includes three or more joint portions formed between adjacent annular bodies. The in-vivo indwelling stent according to any one of claims 1 to 4, wherein the joint mechanism substantially prevents twisting of adjacent annular bodies in the circumferential direction. 6. The in-vivo indwelling device according to any one of claims 1 to 5, wherein the adjacent annular bodies include adjacent bent vertex portions, and the joint mechanism is formed between adjacent bent vertex portions of adjacent annular bodies. Stent. 6. Both adjacent said annular bodies have a linear part extended in the other annular body direction, The said joint mechanism is formed between the edge parts which the said linear part opposes. The stent for in-vivo indwelling. Each of the annular bodies includes an endless first wavy annular body that is annularly continuous, and a second wavy annular body that is disposed in the axial direction so that a peak portion is close to a valley portion of the first wavy annular body. And at least one joint for connecting the trough of the first wavy annular body and the crest of the second wavy annular body close to the first wavy annular body. The stent for in-vivo indwelling. Each of the annular bodies is composed of an annular body in which linear ring portions that are long in the axial direction of the stent are arranged so as to surround the central axis of the plurality of stents, and adjacent linear ring portions are connected by a joint portion. The in-vivo stent according to any one of claims 1 to 7. The in vivo body according to any one of claims 1 to 7, wherein each of the annular bodies is a wavy annular body having a plurality of one-end-side bent apexes of the plurality of stents and a plurality of other-end-side bent apexes of the plurality of stents. 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 in-vivo indwelling in any one of thru | or 10. 11. The stent according to any one of claims 1 to 10, wherein 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. The stent for in-vivo indwelling. 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 instrument comprising the stent according to claim 11. 13. A sheath, comprising: a stent according to claim 12 housed in a distal end portion of the sheath; and an inner tube through which the stent is slidably inserted and discharged from the distal end of the sheath. A living organ dilator.

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