JP2002172176A - In vivo indwelling stent and implement for dilating organism - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an in vivo indwelling stent which is provided with flexibility in a vertical direction concerning an axial direction and by which a cylindrical shape in the whole stent is kept against extension/contraction in the axial direction. SOLUTION: The stent 1 is constituted of circular units 4 having first waveform circular bodies 12a which are formed to be circular by waveform elements, second waveform circular bodies 12b which are arranged in the axial direction of the stent 1 to permit each chevron part to be close to each valley part in the first waveform circular bodies 12a and formed to be circular by the waveform elements and more than one connection parts 6 for connecting the valley parts of the first circular bodies 12a to the chevron parts of the second circular bodies 12b. The circular units 4 are provided with connection parts 7 which are arrayed in the axial direction of the stent 1 so as to connect the adjacent circular units at each connection part forming part. The connection parts 7 are arranged at facing positions to each unit 4 or arranged to have nearly same angle concerning the center axis of the stent.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stent for indwelling a living body and a living organ dilatation used for improving a stenosis or an obstruction in a living body lumen such as a blood vessel, a bile duct, a trachea, an esophagus, and a urethra. Equipment related.

[0002]

2. Description of the Related Art Stents are used to expand a stenosis or occlusion site and secure the lumen to treat various diseases caused by stenosis or occlusion of a blood vessel or other body lumen. It is a generally tubular medical device to be placed there. Since the stent is inserted into the body from outside the body, the diameter of the stent at that time is small. The stent is expanded at a target stenosis or occlusion site to increase the diameter, and the lumen is kept as it is.

[0003] As a stent, a metal wire or a cylindrical shape obtained by processing a metal tube is generally used. Attached in a thin state to a catheter etc., inserted into the living body,
The luminal shape is maintained by expanding it at a target site by any method, and closely contacting and fixing the luminal inner wall. The stent is
According to the function and the placement method, a self-expandable stent and a balloon expandable stent are distinguished. The balloon expandable stent has no expansion function in the stent itself. After inserting the stent into the target site, the balloon is positioned inside the stent to expand the balloon, and the stent is expanded (plastic deformation) by the expansion force of the balloon. Closely fix the inner surface of the lumen. In the case of this type of stent, the operation of expanding the stent as described above is required. The balloon expand type occupies most of the stent used for the treatment of the internal vascular system, particularly the coronary artery. And as a stent,
An axially flexible structure is required to accommodate more cases.

[0004]

The stent needs to be deformed about 2-3 times in diameter. In order to enable the above-mentioned deformation, a current stent using a metal material has a structure bent along the circumferential direction, and a structure in which the diameter of the stent is expanded and contracted by expanding and contracting the bent portion. There is. Furthermore, in order to have flexibility perpendicular to the axial direction, it is necessary that the portion connecting the expandable structural parts has a degree of freedom for bending. That is, it is necessary to design the connecting part itself to have flexibility or to reduce the number of connecting parts as much as possible. However, when flexibility is given to the connecting portion itself, the structure becomes easy to extend in the axial direction. Also, if the number of the connecting portions is too small or the arrangement position is biased, the flexibility may have directivity or the structure may be weak against tension in the axial direction. Conversely, increasing the number of connecting portions increases the strength in the axial direction, but reduces flexibility. As a result, it is necessary to arrange an appropriate number of connecting portions in a well-balanced manner. An object of the present invention is to provide a stent for indwelling a living body which has flexibility in a direction perpendicular to the axial direction and can maintain the cylindrical shape of the entire stent against expansion and contraction in the axial direction. .

[0005]

Means for achieving the above object are as follows: (1) It is formed in a substantially tubular body, has a diameter for insertion into a lumen in a living body, and has a radial direction from the inside of the tubular body. A stent that is expandable when a force is applied that spreads over a first wavy ring formed by a wavy element in an annular shape, and a crest at a valley of the first wavy annular body. A second wavy annular body formed in an annular shape by wavy elements arranged in the axial direction of the stent so as to be close to each other; a valley of the first wavy annular body; and a crest of the second wavy annular body. A plurality of annular units each including a plurality of connecting portions for connecting the plurality of connecting portions are arranged in the axial direction of the stent, and include a connecting portion that connects adjacent annular units at the connecting portion forming site and is not continuous in the axial direction of the stent. , And the connecting portion is formed with an adjacent annular unit. It is indwelling stent which is provided so as to be equiangular arranged about the central axis of the plurality and facing position or the stent between and.

(2) In the above (1), at least one of the plurality of connecting portions of the annular unit includes a valley portion of the first wavy annular body and a peak of the second wavy annular body. It is preferable that the portion is an integrated portion and the other connection portion is a fine wire connection portion. (3) In the above (2), at least one of the plurality of connecting portions provided between the adjacent annular units is for connecting the integrated portions of the adjacent annular units to each other. Is preferably for connecting the thin line-shaped connecting portion forming portions of the adjacent annular units to each other. (4) In any of the above (1) to (3),
It is preferable that the connecting portion is inclined at a predetermined angle with respect to the central axis of the stent, and that the connecting portions adjacent to each other in the axial direction of the stent have different inclination directions. (5) In any of the above (1) to (4),
The connection part, the connection part and the connection part adjacent to the stent in the axial direction are shifted by a predetermined angle with respect to the central axis of the stent, and are arranged so that the connection part has a spiral shape that is intermittent. preferable. (6) In any one of the above (1) to (4),
The plurality of connection portions, the plurality of connection portions, and the plurality of connection portions adjacent to each other in the axial direction of the stent are shifted by a predetermined angle with respect to the central axis of the stent, and have a plurality of spiral shapes in which the connection portions are interrupted. It is preferable that they are arranged as follows. (7) In any of the above (1) to (4),
The plurality of connecting portions are arranged at positions facing each other,
The plurality of connecting portions and the plurality of connecting portions adjacent in the axial direction of the stent are displaced by about 60 degrees with respect to the central axis of the stent, and are arranged such that the connecting portions form a plurality of intermittent spirals. Is preferred.

In order to achieve the above object, (8) a substantially tubular body having a diameter for insertion into a living body lumen, and a force spreading radially from inside the tubular body. An expandable stent when applied, wherein the stent comprises a plurality of substantially polygonal linear bodies having a plurality of linear bends and openings that expand when the radially expanding force is applied. A plurality of annular units connected by a plurality of connecting portions are arranged in the axial direction of the stent, and a connecting portion that connects adjacent annular units at the connecting portion and is not continuous in the axial direction of the stent, The connecting portion is a stent for indwelling in a living body provided between a plurality of adjacent annular units so as to be arranged at a plurality of positions facing each other or at substantially the same angle with respect to the central axis of the stent.

(9) In the above (8), the connecting portion is inclined at a predetermined angle with respect to a central axis of the stent, and connecting portions adjacent to each other in the axial direction of the stent have different inclination directions. Preferably, it is (10) In the above (8) or (9), the connection part and the connection part adjacent to the connection part in the axial direction of the stent are shifted by a predetermined angle with respect to the central axis of the stent, and the connection part is intermittent. It is preferable to arrange them so as to form a spiral shape. (11) In the above (8) or (9), the plurality of connecting portions, and the plurality of connecting portions and the plurality of connecting portions adjacent in the axial direction of the stent are shifted by a predetermined angle with respect to the central axis of the stent. At the same time, it is preferable that the connecting portions are arranged so as to form a plurality of intermittent spirals. (12) In the above (8) or (9), the plurality of connecting portions are arranged at positions facing each other, and the plurality of connecting portions and the plurality of connecting portions adjacent to each other in the axial direction of the stent are connected to the stent. It is preferable that the connecting portion is arranged so as to be displaced by about 60 degrees with respect to the central axis, and to have a plurality of intermittent spiral shapes. (13) In any one of the above (1) to (12), it is preferable that the wavy ends of the adjacent annular units penetrate into the space formed between the adjacent wavy elements of the annular unit.

In order to achieve the above object, (14) a tubular shaft main body, a foldable and expandable balloon provided at a distal end of the shaft main body, and the balloon in a folded state And a stent that is mounted so as to encapsulate the stent and that is expanded by expanding the balloon, wherein the stent is the stent according to any one of (1) to (13) above. This is a living organ dilator.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A stent according to the present invention will be described with reference to an embodiment shown in the drawings. FIG. 1 is a front view of one embodiment of the stent of the present invention. FIG. 2 is a partially enlarged view of the stent shown in FIG. FIG. 3 is a development view of the stent shown in FIG. 1 before expansion. The stent 1 of this embodiment is
The stent is formed in a substantially tubular body, has a diameter for insertion into a body lumen, and is expandable when a force that spreads radially from inside the tubular body is applied. The stent 1 includes a first wavy annular body 12a formed in an annular shape by a wavy element having a large number of bent portions 5a, and a first wavy annular body 12a.
A second wavy annular body 12b, which is arranged in the axial direction of the stent 1 so that the peaks are close to the valleys and is annularly formed by a wavy element having the linear bent portion 5a, The annular unit 4 includes a plurality of connecting portions 6 connecting the valleys of the body 12a and the peaks of the second wavy annular body 12b. Further, the annular units 4 are arranged in a plurality in the axial direction of the stent 1. And a connecting portion 7 for connecting adjacent annular units at a connecting portion forming portion. Further, the connecting portions 7 are provided so as to be arranged at a plurality of positions facing each other between the adjacent annular units 4 or substantially equiangularly with respect to the center axis of the stent.

The stent 1 is a so-called balloon expandable stent. As shown in FIGS. 1 to 3, the stent 1 includes a plurality of annular units 4 arranged so as to be substantially linear in the axial direction of the stent 1, and a corrugated element (corrugated circular body) of adjacent circular units. 1
2b and 12a) are provided at the connecting portion 6 at the connecting portion. From a different point of view, the stent 1 is a tubular body formed by connecting a number of annular units 4 by connecting portions 7. The annular units 12a and 12b of the stent 1 have six peaks and valleys of substantially the same pitch and are formed of an endless wavy body that is annularly continuous, as shown in FIG. I have. The number of peaks (or valleys) of the annular unit is 4
7 are preferable. The second wavy annular body 12b, which is arranged in the axial direction so that the crest is close to the valley of the first wavy annular body 12a, is formed by the valley of the first wavy annular body and the second wavy annular body. The ridges of the body are connected by a plurality of short connecting portions 6 to form one annular unit 4. In this embodiment, all the valleys of the first wavy annular body 12a and all the valleys of the second wavy annular body 12b are connected by the connecting portion 6, and one annular unit 4 has six ( (The number of peaks or valleys of the annular unit).

The annular units 4 configured as described above are arranged in a plurality (12 in this embodiment) in the axial direction of the stent 1 and include a connecting portion 7 for connecting adjacent annular units. As a result, a cylindrical stent 1 is formed. And the connection part 7
It is provided so that adjacent annular units 4 may be connected at a plurality of locations. The number of connecting portions provided between two adjacent annular units is preferably 2 to 4. Furthermore, the connection part 7 is arrange | positioned so that it may not be continuous with an adjacent connection part. In the stent 1, two connecting portions 7 are provided between the adjacent annular units 4 as shown in FIGS. 1 to 3. That is, the adjacent annular units 4 are connected at two places.

At least one of the plurality of connecting portions of the annular unit 4 is connected to the first wavy annular body 12.
The valley of a and the crest of the second wavy annular body 12b form an integrated part 4a. The other connecting portions 6 are thin connecting portions. At least one connecting portion 7a of the plurality of connecting portions provided between the annular units connects the integrated portions 4a of the adjacent annular units 4 to each other. Further, another connecting portion 7b connects the portions of the adjacent annular units 4 where the thin wire connecting portions 6 are formed. That is, in the stent of this embodiment, the adjacent annular units are the first wavy annular bodies 12a of the respective annular units.
Are connected to each other by the integrated portion 4a in which the valley portion of the second wavy annular body 12b is integrated, and the units 4 have a sufficient connection strength. Further, the adjacent annular units are provided with another (second) connecting portion 7b for connecting the forming portions of the thin wire connecting portions 6 to each other. For this reason, it is possible to suppress the extension of the stent after being placed in the living body, and
Since it is not a connection in the integrated portion, it does not become a bending obstacle.

The plurality of connecting portions 7 connecting the annular units 4 are inclined at a predetermined angle with respect to the central axis of the stent 1. In other words, in a state where the stent is cut in the longitudinal direction parallel to the central axis of the stent and deployed, the connecting portion is inclined at a predetermined angle with respect to the longitudinal direction of the stent. Further, in the stent 1 of the embodiment shown in the drawings, the connecting portions connecting two identical adjacent annular units are inclined in the same direction and at substantially the same angle. In the stent 1 of this embodiment, the connecting portions adjacent to each other in the axial direction of the stent have different inclination directions. Furthermore, the connection part 7 is arrange | positioned so that it may not be continuous with an adjacent connection part. Also, the connecting portion 7 (7a, 7b)
The connecting portions 7 (7a, 7b) and the connecting portions 7 (7a, 7b) adjacent to each other in the axial direction of the stent 1 are shifted by a predetermined angle with respect to the central axis of the stent 1, so that the connecting portions 7
(7a, 7b) are arranged so as to form an intermittent spiral shape. In other words, the plurality of connecting portions 7a, 7b and the plurality of connecting portions 7a, 7b adjacent to the plurality of connecting portions 7a, 7b in the axial direction of the stent are formed at a predetermined angle with respect to the central axis of the stent (see FIG. 3). In the example, the connection portions 7a and 7b are arranged so as to be shifted by about 60 degrees).
It is arranged so as to form a plurality of (two) intermittent spirals.

As described above, in the stent 1, as shown in FIG. 3, the connecting portions 7a and 7b are not continuous in the axial direction of the stent and are arranged in two spirals. Further, the connecting portions at positions adjacent to each other in the axial direction have different inclination directions. Further, the integrated portion is in a state of being spirally arranged. As a result, the stent can be satisfactorily deformed as a whole without having a bending direction. Having no bending direction means having no easily deformable direction and hardly deformable direction. By making the connecting portion discontinuous in the axial direction of the stent, the load when one annular unit 4 changes so as to follow the deformation of the blood vessel is directly (or linearly) applied to the adjacent annular units 4. ) Can be suppressed, and the independent extension function of each annular unit is exhibited. Furthermore, if the arrangement of the connecting portions is spiral when viewed from the entire stent 1, it is less likely to be affected by the non-adjacent annular units.

Further, in this stent 1, the apex portion of the bent portion 5a of the corrugated annular body of the adjacent annular unit may enter the space formed between the adjacent bent portions of one annular unit. preferable. By doing so, the stent 1 is in a state where the corrugated annular body partially overlaps when viewed in the axial direction of the stent 1. When the stent 1 is expanded, even if the individual components are shortened in the axial direction of the stent 1, the increase in the gap on the side surface of the stent 1 is small, and the stenotic portion of the blood vessel can be more reliably expanded, and Can be pressed without gaps.

The stent 1 has a non-expanded diameter of 0.8
About 1.8 mm is preferable, and especially 0.9 to 1.4 mm.
mm is more preferable. Further, the length of the stent 1 when not expanded is preferably about 9 to 40 mm. The length of one wavy annular body 12a, 12b is 0.7 to 2.0 mm
The degree is preferred, and the length of one annular unit is:
A thickness of about 5 to 4.0 mm is suitable, and in particular, 2.0 to 3.0 mm.
0 mm is more preferable. Also, one wavy annular body 12
The number of peaks of a and 12b (in other words, the number of valleys) is 4 to
8 is preferred, and 5-7 is particularly preferred. Further, the length of the fine wire-like connecting portion 6 is preferably about 0.01 to 0.5 mm. Further, the width of the fine wire-shaped connection portion is preferably 0.02 to 0.04 mm, more preferably 0.0
25 to 0.035 mm. In addition, the width of the thin wire connection portion is 0.06 to 0.15 mm when not broken,
More preferably, it is 0.08 to 0.13 mm. And the width | variety of an integrated part is 0.06-0.15 mm, More preferably, it is 0.08-0.13 mm.

The number of the annular units is preferably from 3 to 50. In addition, the length at which the components (annular units) of adjacent annular units overlap in the axial direction of the stent 1 is as follows:
0.5-1 mm is preferred. The center-to-center distance between the annular units is preferably 1.3 to 2.5 mm. The length of the connecting portion 7 is preferably from 1.4 to 2.7 mm. Further, the inclination angle of the connecting portion with respect to the central axis of the stent 1 (the inclination angle with respect to the longitudinal direction as viewed in a developed view) is 0 ° to 45 °.
Degree is preferable, and in particular, 5 ° to 25 ° is preferable.
The diameter of the stent 1 at the time of molding (before compression) is 1.
A thickness of about 5 to 3.5 mm is preferable, and in particular, 2.0 to 3.5 mm.
0 mm is more preferable. Further, the thickness of the stent 1 is preferably about 0.05 to 0.15 mm, particularly preferably 0.08 to 0.12 mm, and the width of the corrugated element is 0.07 to 0.15 mm. The degree is preferable, and particularly, 0.08 to 0.13 mm is preferable.

The stent 1 of the above-described embodiment is of a type in which adjacent annular units are connected by two connecting portions. For this reason, the connecting portion is disposed at a position facing the central axis of the stent.
However, the present invention is not limited to this embodiment.
4) to 4) may be provided. In this case, the connecting portions are provided so as to be substantially equiangular with respect to the central axis of the stent. That is, when three connecting parts are provided between adjacent annular units, the arrangement is about every 120 degrees, and when four connecting parts are provided, the arrangement is about every 90 degrees. In addition, even when three or more connecting portions are provided between adjacent annular units, it is preferable that one annular unit includes only one integrated portion. That is, it is preferable that only one connecting portion connects the integrated portions of the adjacent annular units, and that the other two or more connecting portions connect the thin wire connecting portion forming portions.

As a material for forming the stent 1, 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-based alloy or the like can be considered. Further, after forming the stent shape, noble metal plating (gold, platinum) may be performed. As stainless steel, SUS316L, which has the highest corrosion resistance, is preferable.

The stent 1 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. The chemical polishing is preferably performed by dipping in a stainless chemical polishing liquid. As stainless steel chemical polishing liquid,
Any material capable of dissolving stainless steel may be used.For example, a mixed solution of hydrochloric acid and nitric acid is used as a basic component, and an organic sulfur compound and a surfactant for dissolution rate adjustment, smoothing and gloss imparting are added thereto. Are preferred.

Furthermore, it is preferable to anneal the stent 1 after the final shape is prepared. 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 with the case where the annealing is not performed, the force for restoring the stent 1 to the pre-expansion shape after the expansion, particularly the force for returning to the linear shape developed when the stent 1 is expanded at the bent vascular site is reduced, The physical stimulus applied to the bent blood vessel inner wall is reduced, and the cause of restenosis can be reduced. Annealing can be 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, a stent according to another embodiment of the present invention will be described with reference to the drawings. FIG. 4 is a front view of one embodiment of a stent according to another embodiment of the present invention. FIG.
FIG. 5 is a partially enlarged view of the stent shown in FIG. 4. FIG. 6 is a development view of the stent shown in FIG. The stent 10 of this embodiment is formed in a substantially tubular body, has a diameter for insertion into a body lumen, and is expandable when a force that spreads radially from the inside of the tubular body is applied. is there. The stent 10 is formed by connecting a plurality of substantially polygonal linear bodies 13 having a large number of linear bent portions and openings which are expanded when a force spreading in a radial direction is applied thereto by a plurality of connecting portions 16 so as to form an annular shape. A plurality of units 14 are arranged in the axial direction of the stent, and are provided with connecting portions 15 that connect adjacent annular units 14 at connecting portions and are not continuous in the axial direction of the stent. It is provided so as to be arranged at a plurality of positions facing each other or at substantially equiangular positions with respect to the central axis of the stent.

This stent is a so-called balloon expandable stent. As in the stent of this embodiment, it is preferable that the substantially polygonal linear body 13 has a shape that is long and flat in the axial direction of the stent. further,
As in the stent of this embodiment, the substantially polygonal linear bodies 13 located at both ends of the stent preferably have substantially semi-elliptical outer portions. Further, like the stent of this embodiment, the space formed between the bent portions 11a of the substantially polygonal linear bodies 13 adjacent to each other in the annular unit has substantially polygonal linear bodies of the other adjacent annular units 14. It is preferable that the apex portion of the 13 bent portion 11a is penetrated.

As shown in FIG. 4, FIG. 5 and FIG. 6, which is a developed view of FIG. 4, the stent 10 is a substantially polygonal line which is long in the axial direction of the stent 10 and has a linear bent portion 11a and a central opening. The linear bodies 13 are arranged on the circumference at substantially equiangular positions with respect to the central axis of the stent, and a connection portion is formed between adjacent parts (side parts) of the substantially polygonal linear bodies 13 in the circumferential direction. The annular unit 14 is connected at 16, and a plurality of annular units 14 are arranged in the axial direction of the stent 10. Further, the connecting portion 16 of one annular unit 14 and the connecting portion 16 of the adjacent annular unit 14 are connected by a connecting portion 15 in at least two places. Stent 10
From a different point of view, is a tubular body formed by connecting a number of annular units 14 by connecting portions 15.

In this embodiment, the annular unit 14 comprises six substantially polygonal linear bodies 13 arranged at substantially equal angular intervals.
Having. One substantially polygonal linear body 13 is the stent 1
0 is formed in a substantially rhombic shape which is long in the axial direction, and the center thereof is opened in a substantially rhombic shape corresponding to the shape of the substantially polygonal linear body 13, and both ends in the axial direction of the stent are linear bent portions 11a. It has become. As described above, each of the substantially polygonal linear bodies 13 has a shape that forms an independent closed system, in other words, each of the substantially polygonal linear bodies 13 is a ring-shaped element that opens on the side surface of the stent 10. Since the substantially polygonal linear body 13 has such a shape, it exhibits a strong expanded holding force. Further, each of the substantially polygonal linear bodies 13 is curved in the circumferential direction so that the whole is substantially equidistant from the central axis of the stent 10.

The substantially polygonal linear body 13 is a connecting portion in which the center of the axial side of the stent 10 and the center of the axial side of the other substantially polygonal linear body 13 adjacent in the radial direction are short. 16
Connected by That is, the connection portion 16 connects the substantially polygonal linear bodies 13 in the circumferential direction. Since the connecting portion 16 does not substantially change even when the stent 10 is expanded, a force at the time of expansion is likely to be applied to the center of each substantially polygonal linear body 13, and each substantially polygonal linear body 13 is uniformly formed. It can be extended (deformed). The number of the substantially polygonal linear bodies 13 is
The number is not limited to six, but preferably four to eight. In addition, the shape of the substantially polygonal linear body 13 is preferably a polygonal shape having vertices facing in the axial direction of the stent, and may be particularly a rhombus, hexagon, octagon, or the like.
Preferably, the shape is substantially rhombic from the viewpoint of the stability of deformation when the stent is expanded.

The connecting portion 16 of the annular unit 14 and the connecting portion 16 of the adjacent annular unit 14 are relatively long (longer than the connecting portion) and are connected by the connecting portion 15 formed parallel to the axial direction of the stent 10. Are linked. In particular,
The annular unit 14 and the adjacent annular unit 14 are connected by a connecting portion 15 connecting between the connecting portions 16. These connectors 15 do not change substantially when the stent 10 is expanded. The connecting portion 15 and the connecting portion 16
Since the expansion of the stent 10 does not substantially change, the overall length of the entire stent 10 hardly changes before and after expansion, and the stent does not become extremely short after expansion. In other words, the connecting portion 16 connecting the expansion elements does not move in the axial direction even when the stent is expanded, and the connecting portion is connected by the connecting portion 15 parallel to the axis. It does not shorten. The connecting portion 15 is provided so as to connect the adjacent annular units 14 at a plurality of locations. The number of connecting portions provided between two adjacent annular units is preferably two to three, and particularly preferably two. Further, the connecting portion 15
It is arranged so as not to be continuous with the connecting part adjacent in the axial direction,
In addition, the directions (angles) are shifted from each other.

The plurality of connecting portions connecting the annular units are inclined at a predetermined angle with respect to the central axis of the stent 10. In other words, in a state where the stent is cut and deployed in the longitudinal direction parallel to the central axis of the stent,
The connecting portion is inclined at a predetermined angle with respect to the longitudinal direction of the stent. And in the stent 10 of this embodiment,
The connecting portions connecting the same adjacent annular units are inclined in the same direction. Further, in the stent 10 of the embodiment shown in the drawings, the connecting portions connecting the same adjacent annular units are inclined in the same direction and at substantially the same angle. Also,
The connecting portions adjacent to each other in the axial direction of the stent have different inclination directions. Further, the connecting portion 15 is arranged so as not to be continuous with the adjacent connecting portion. Further, the connecting portion 15 and the connecting portion 15 adjacent to the connecting portion 15 in the axial direction of the stent 1 are shifted by a predetermined angle with respect to the central axis of the stent 10 so that the connecting portion 15 has a spiral shape that is intermittent. Are located in That is, a plurality of connecting portions 1
5, the plurality of connecting portions 15 and the plurality of connecting portions 15 adjacent in the axial direction of the stent are arranged so as to be shifted by a predetermined angle (about 60 degrees in the embodiment shown in FIG. 6) with respect to the central axis of the stent. As a result, the connecting portions 15 are arranged so as to form a plurality of (two) intermittent spirals.

As described above, in the stent 10, as shown in FIG. 6, the connecting portions 15 are not continuous in the axial direction of the stent and are arranged in two spirals. The connecting portions at positions adjacent to each other in the axial direction have different inclination directions. As a result, the stent can be satisfactorily deformed as a whole without having a bending direction. Having no bending direction
It means that it has no easily deformable direction and hardly deformable direction. By making the connection part discontinuous in the axial direction of the stent, the load when one annular unit 14 changes so as to follow the deformation of the blood vessel is directly (or linearly) applied to the adjacent annular units 14. ) Can be suppressed, and the independent extension function of each annular unit is exhibited. Further, the arrangement of the connecting portion is different from that of the stent 10.
If it is spiral as a whole, it is less susceptible to the effects of non-adjacent annular units.

The outer portion 13b of the substantially polygonal linear body 13 located at both ends of the stent 10 has a substantially semi-elliptical shape. By doing so, the expansion force at the end can be made sufficient, and damage to the indwelling blood vessel inner wall and the balloon can be reduced. Also, all the substantially polygonal linear bodies 13 are:
So that the whole is almost equidistant from the central axis of the stent,
It is curved in the circumferential direction. Further, in the stent 10, the space formed between the bent portions of two adjacent substantially polygonal linear bodies 13 of the annular unit 14 includes the bent portions of the substantially polygonal linear bodies 13 of the adjacent annular unit 14. It is preferable that the top portion of 11a is penetrated. By doing so, in the stent 10, the annular units partially overlap when viewed in the axial direction of the stent. Even when each of the substantially polygonal linear bodies 13 is shortened in the axial direction of the stent 10 when the stent 10 is expanded, the increase in the gap on the side surface of the stent 10 is small, and the stenotic portion of the blood vessel can be more reliably expanded. And the maintenance will be higher.

The non-expanded diameter of the stent 10 is preferably about 0.6 to 1.8 mm.
1.6 mm is more preferred. Further, the length of one annular unit, in other words, the length of one substantially polygonal linear body in the axial direction is preferably about 1.5 to 4.0 mm, and particularly preferably 2.0 to 3.0 mm. 0 mm is more preferable. Further, the number of the annular units is 3 to 10, preferably 3 to 8. The thickness of the annular unit at the center of the stent 10 is preferably about 0.05 to 0.12 mm,
In particular, 0.06 to 0.10 mm is preferable. The thickness of the stent is preferably about 0.05 to 0.09 mm. The diameter of the stent 10 at the time of molding (before compression) is preferably about 1.5 to 3.5 mm.
0 to 3.0 mm is more preferable.

The stent 10 of the above-described embodiment is of a type in which adjacent annular units are connected by two connecting portions.
It is arranged at a position facing the central axis of the stent. However, it is not limited to this embodiment,
Between the adjacent annular units, 3 to 4 (2 to 4 including the above 2) connecting portions may be provided. In this case,
The connecting portions are provided so as to be substantially equiangular with respect to the central axis of the stent. That is, when three connecting portions are provided between adjacent annular units, the arrangement is made at intervals of about 120 degrees. As a material for forming the stent 10, 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-based alloy, or the like can be considered. Further, after forming the stent shape, noble metal plating (gold, platinum) may be performed. As stainless steel, SUS316L, which has the highest corrosion resistance, is preferable.

Furthermore, it is preferable to anneal the stent 10 after the final shape is prepared. 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 for restoring the pre-expansion shape after expanding the stent, especially the force for returning to the linear shape developed when expanded at the bent vascular site is reduced, The physical stimulus given to the vascular inner wall which has been reduced can be reduced, and the cause of restenosis can be reduced. Annealing is preferably performed by heating to 900 to 1200 ° C. in an inert gas atmosphere (eg, argon gas) and then slowly cooling so that an oxide film is not formed on the stent surface.

The stent 10 is preferably chamfered. The chamfering method of the stent 10 can be performed by forming the stent into a final shape and then performing chemical polishing, electrolytic polishing, or mechanical polishing. The chemical polishing is preferably performed by dipping in a stainless chemical polishing liquid. As the stainless chemical polishing liquid, any liquid capable of dissolving stainless steel may be used.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 is used. And what added the surfactant is preferable.

Next, the vascular dilator according to the present invention will be described with reference to an embodiment shown in the drawings. FIG. 7 is a front view of the living organ dilator according to the embodiment of the present invention. FIG. 8 is an enlarged partial cross-sectional view of the distal end portion of the living organ dilator shown in FIG. FIG. 9 is an enlarged cross-sectional view of the rear end of the living organ dilator shown in FIG. In the vasodilator 100 of the present invention,
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 101 which is mounted so as to enclose the stent 101 and is expanded by expansion of the balloon 103.

The stent 101 is formed in a substantially tubular body, has a diameter for insertion into a body lumen, and is expandable when a force spreading radially from the inside of the tubular body is applied. In this case, there is used one having a large number of linear bends that expand when a force that expands in the radial direction is applied, and a portion including the apex of the bend is curved inside the stent. As such a stent 101, for example, the above-described stent 1 or stent 10
Can be used. Further, in the vascular dilatation device 100 of the present invention, the shaft body 102 has one end of the balloon 1.
03 is provided with a balloon expansion lumen communicating with the inside. The living organ dilator 100 is fixed to the outer surface of the X-ray opaque member fixed to the outer surface of the shaft main body at the position of the center of the stent or to the outer surface of the shaft main body at positions at both ends of a predetermined length of the center of the stent. Provided with two X-ray opaque members. Biological organ expansion device 100 of this embodiment
As shown in FIG. 7, the shaft main body 102 includes a guide wire lumen 115 having one end opened at the front end of the shaft main body 102 and the other end opened at the rear end of the shaft main body 102. I have.

The living organ dilator 100 includes a shaft main body 102, a stent expansion balloon 103 fixed to the distal end of the shaft main body 102, and a stent 101 on which the balloon 103 is mounted. The shaft body 102 includes an inner tube 112, an outer tube 113, and a branch hub 110. As shown in FIGS. 8 and 9, the inner tube 112 is a tube body provided with a guide wire lumen 115 for inserting a guide wire therein. The length of the inner tube 112 is 100 to 200.
0 mm, more preferably 150 to 1500 mm, the outer diameter is 0.1 to 1.0 mm, more preferably 0.3 to
0.7 mm, wall thickness 10 to 150 μm, more preferably,
It is 20 to 100 μm. And the inner tube 112
Is inserted through the inside of the outer tube 113, and the distal end of the
13 protrudes. The outer surface of the inner tube 112 and the outer tube 1
A balloon inflation lumen 116 is formed by the inner surface of 13 and has a sufficient volume. The outer tube 113 is
This is a tube body in which the inner tube 112 is inserted and the tip is located at a position slightly retreated from the tip of the inner tube 112. The outer tube 113 has a length of 100 to 2000 mm, more preferably 150 to 1500 mm, and an outer diameter of 0.5 to
1.5 mm, more preferably 0.7 to 1.1 mm, wall thickness 25 to 200 μm, more preferably 50 to 100 μm
m.

In the living organ dilator 100 of this embodiment, the outer tube 113 includes the distal outer tube 113a and the main outer tube 1a.
13b, and both are joined. Then, the distal end side outer tube 113a is tapered in a portion closer to the distal end side than the joint with the main body side outer tube 113b,
The distal end has a smaller diameter than the tapered portion. The outer diameter at the small diameter portion of the distal outer tube 113a is 0.50 to 1.5 m
m, preferably 0.60 to 1.1 mm. The outer diameter of the proximal end of the distal outer tube 113a and the outer diameter of the main outer tube 113b are 0.75 to 1.5 mm, preferably 0.9 to 1.5 mm.
1.1 mm.

The balloon 103 has a distal joint 103a and a rear joint 103b. The distal joint 103a is fixed at a position slightly rearward from the distal end of the inner tube 112. The joint 103b is fixed to the distal end of the outer tube. The balloon 103 communicates with the balloon expansion lumen 116 near the base end. Inner tube 1
The material for forming the outer tube 12 and the outer tube 113 is preferably a material having a certain degree of flexibility, for example, polyolefin (for example, polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, etc.), Thermoplastic resins such as vinyl chloride, polyamide elastomer and polyurethane, silicone rubber, latex rubber and the like can be used, preferably the above-mentioned thermoplastic resins, and more preferably polyolefin.

As shown in FIG. 8, the balloon 103 is foldable and can be folded around the inner tube 112 when not expanded. The balloon 103 is mounted on the stent 10 to be mounted.
1 has an expandable portion which is a cylindrical portion (preferably a cylindrical portion) having substantially the same diameter so as to be expandable. The substantially cylindrical portion does not need to be a perfect cylinder and may be a polygonal column. As described above, the balloon 103 has the distal-side joint portion 103a fixed to the inner tube 112 and the rear-end side joint portion 103b fixed to the distal end of the outer tube 113 in a liquid-tight manner using an adhesive or heat fusion. . In the balloon 103, a portion between the expandable portion and the joint portion is formed in a tapered shape.

The balloon 103 forms an expansion space 103c between the inner surface of the balloon 103 and the outer surface of the inner tube 112. This expansion space 103c communicates with the expansion lumen 116 on the entire periphery at the rear end. As described above, the rear end of the balloon 103 communicates with the expansion lumen having a relatively large volume, so that the inflation 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, a polyolefin (for example, polyethylene, polypropylene, ethylene-
Propylene copolymer, ethylene-vinyl acetate copolymer,
Thermoplastic resins such as cross-linked ethylene-vinyl acetate copolymer), polyvinyl chloride, polyamide elastomer, polyurethane, polyester (eg, polyethylene terephthalate), polyarylene sulfide (eg, polyphenylene sulfide), silicone rubber, and latex rubber Etc. can be used. Particularly, the balloon 103 is preferably a stretchable material, and the balloon 103 is preferably biaxially stretched having high strength and expansion force.

As for the size of the balloon 103, the outer diameter of the cylindrical portion (expandable portion) when expanded is 2 to 4 m.
m, preferably 2.5-3.5 mm and a length of 10
５０50 mm, preferably 20-40 mm. Also,
The outer diameter of the distal end side joint portion 103a is 0.9 to 1.5 mm,
Preferably it is 1 to 1.3 mm, the length is 1 to 5 mm,
Preferably it is 1 to 1.3 mm. Further, the outer diameter of the rear end side joint portion 103b is 1 to 1.6 mm, preferably 1.1.
~ 1.5mm, length 1 ~ 5mm, preferably
2 to 4 mm.

The vascular dilatation device 100 is similar to that shown in FIG.
As shown in, the cylindrical part when expanded (expandable part)
And two X-ray opaque members 117 and 118 fixed to the outer surface of the shaft body at positions that are both ends of the shaft body. In addition, the shaft main body 102 (in this embodiment, the inner tube 11
It may be provided with two X-ray opaque members fixed to the outer surface of 2). Further, a single X-ray opaque member fixed to the outer surface of the shaft main body at a position to be the center of the stent may be provided. X-ray contrast member 11
7, 118 are preferably a ring-shaped member having a predetermined length, or a linear member wound in a coil shape, and the forming material is, for example, gold, platinum, tungsten or an alloy thereof, or Silver-palladium alloys and the like are preferred.

As shown in FIG. 9, a linear stiffening member 133 is inserted between the inner tube 112 and the outer tube 113 (in the balloon expansion lumen 116). The rigidity imparting member 133 prevents the main body 102 of the living body organ expansion device 100 from being extremely bent at the bending portion without significantly reducing the flexibility of the living body organ expansion device 100, Easy to push the tip. The distal end of the rigidity imparting member 133 has a smaller diameter than other parts by a method such as polishing. In addition, the rigidity imparting body 133 has a small-diameter portion whose tip is
It is preferable to extend to the vicinity of the front end of the base. The stiffness imparting body is preferably a metal wire and has a wire diameter of 0.0
5 to 1.50 mm, preferably 0.10 to 1.00 mm
Elastic metal such as stainless steel, super-elastic alloy, etc.
Particularly preferred are high-strength stainless steel for springs and superelastic alloy wires.

In the living organ dilator 100 of this embodiment, as shown in FIG. 9, a branch hub 110 is fixed to the base end. The branch hub 110 has a guide wire inlet 109 communicating with the guide wire lumen 115 to form a guide wire port. The branch hub 110 communicates with an inner tube hub 122 fixed to the inner tube 112 and a balloon expansion lumen 116, and an injection port. 111 and an outer tube 113
The outer tube hub 123 is fixed to the outer tube hub 123. The outer tube hub 123 and the inner tube hub 122 are fixed. 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 suitably used.

In this embodiment, a bend preventing tube 150 is provided at the end of the outer tube 113. The bend preventing tube 150 has heat shrinkability, and is formed such that the inner diameter after heat shrinkage is slightly smaller than the outer diameter of the outer tube 113.
0 is fitted to the end of the outer tube 113, and is attached by heating (for example, applying hot air) to contract. The bend preventing tube 150 is fixed to the outer tube hub 123 by a stop pin 152. In this fixing method, the outer diameter of a portion other than the rear end portion of the outer tube 113 is substantially equal to the inner diameter of the outer tube 113, and a stop pin 152 having an enlarged rear end portion is inserted, and the outer tube 113 is fixed to the outer tube 113. Insert the outer tube hub 123 into the outer tube hub 123 from the tip.
The protrusion 154 provided on the inner surface of the lock pin 152 is pushed until the rear end portion of the stop pin 152 is pushed. Further, the outer tube hub 123 and the tube 150 for preventing bending are used.
An adhesive may be applied to the contact surface with the adhesive and fixed.

At the end of the inner tube 112, a tube 160 for preventing bending is provided. This tube 16
Numeral 0 denotes a heat-shrinkable tube which is formed so that the inner diameter after heat-shrinkage is slightly smaller than the outer diameter of the inner tube 112, and covers this heat-shrinkable tube 160 on the end of the inner tube 112. It can be easily attached by fitting, heating (for example, applying hot air), and contracting. The base end of the stiffness imparting body 133 is
60 is fixed to the outer surface of the inner tube 112. Then, the inner tube 1 to which the bending preventing tube 160 is attached
12 is fixed to the inner tube hub 122. In this fixing method, an outer diameter of a portion other than the rear end portion is substantially equal to an inner diameter of the inner tube 112 at a rear end of the inner tube 112, and a stop pin 162 having an enlarged rear end portion is inserted. This is performed by inserting the distal end into the inner tube hub 122 and pushing the protrusion 164 provided on the inner surface of the inner tube hub 122 until the rear end portion of the stop pin 162 exceeds. Further, an adhesive may be applied and fixed to the contact surface between the inner tube hub 122 and the bending preventing tube 160. Outer tube hub, inner tube hub and its forming material include polycarbonate,
Thermoplastic resins such as polyamide, polysulfone, polyarylate, and methacrylate-butylene-styrene copolymer can be suitably used.

Then, the inner tube hub 122 and the outer tube hub 123
And are fixed. This fixing is carried out from the rear end of the outer tube hub 123 attached to the base end of the outer tube 113 to the inner tube 112.
Is inserted from the tip and joined. Also, at this time, by applying an adhesive to the joint between the inner tube hub 122 and the outer tube hub 123, the two can be securely fixed. In addition, the living organ dilator 100
The structure of the base end is not limited to the one described above. The branch hub 110 is not provided, and the guide wire lumen 115 and the balloon expansion lumen 116 are each provided with an opening at the rear end, for example. The tube having the member may be attached in a liquid-tight manner.

[0050]

EXAMPLES Specific examples of the stent of the present invention will be described. (Example 1) A stainless steel (SUS316L) having a diameter of 2.0 mm and a wall thickness of 0.095 mm was changed to a length of 20 m.
A metal pipe cut to m was used. As a laser processing machine, NEC's YAG laser (trade name SL116)
E) was used. The metal pipe was set on a jig with a rotary motor equipped with a chuck mechanism so that the shaft did not move, and this was set on an XY table capable of numerical control. Then, the XY table and the rotary motor were connected to a personal computer, and the output of the personal computer was input to the numerical controller and the rotary motor of the XY table. Drawing software is stored in the personal computer.
The input of the developed drawing of the stent in the composition at the time of molding as shown in FIG. With such a configuration, the XY table and the rotary motor are driven based on the drawing data output from the personal computer, and a laser is irradiated to the XY table and the stent structure is manufactured. Laser processing conditions for the metal pipe were a current value of 25 A, an output of 1.5 W and a driving speed of 10 mm / min. Then, the prepared stent structure is subjected to a chemical polishing solution for stainless steel (trade name: Sunbit 505, manufactured by Sanshin Chemical Industry Co., Ltd.).
A mixture of hydrochloric acid and nitric acid as a basic component to which an organic sulfur compound and a surfactant are added) is heated at about 98 ° C. for about 10 minutes and immersed for about 10 minutes, and chamfered (deburring, chemical polishing) is performed. The stent of the present invention was produced.

The stent formed body thus manufactured has 12 annular units, and has two connecting portions at positions opposed to each other between adjacent annular units, and the axial displacement of the connecting portion in the axial direction of the stent is about 60 degrees. And the total length is 20 mm,
The outer diameter is 2.0 mm, the width of the wavy element (wavy annular body) and the portion constituting the connecting portion is 0.12 mm, and the width of the connecting portion is
0.12 mm, the width of the integrated part is 0.12 mm, the length is 0.1 mm, and the thickness of the entire stent is about 0.08 m
m.

Then, this stent formed body is fitted on the balloon portion of a dilatation catheter (balloon catheter) for PTCA, inserted into a mounting device, and the stent is uniformly compressed from the outer surface of the stent toward the center to obtain an outer diameter. 1.0m
m and mounted in a balloon shape to produce a living organ dilator of the present invention having a structure as shown in FIGS. 7 to 9.

Comparative Example 1 A stent according to a comparative example was manufactured in the same manner as in Example 1 except that the composition input into the personal computer during the molding of the stent was changed as shown in FIG. The stent formed body thus produced has 12 annular units, and has only one connecting portion at a position facing between adjacent annular units, and the axial displacement of the stent at the connecting portion is about 180 degrees. Yes, the total length is 20 mm, the outer diameter is 2.0 mm, the width of the part constituting the wavy element (wavy annular body) and the connecting part is 0.12 mm, and the width of the connecting part is
0.12 mm, the width of the integrated part is 0.12 mm, the length is 0.1 mm, and the thickness of the entire stent is about 0.08 m
m. Then, this stent formed body is fitted on the balloon portion of a dilatation catheter (balloon catheter) for PTCA, inserted into a mounting device, and the stent is uniformly compressed from the outer surface of the stent toward the center to have an outer diameter of 1.0 m.
m, and attached to form a balloon to produce a living organ dilator.

Comparative Example 2 A stent according to a comparative example was manufactured in the same manner as in Example 1 except that the composition at the time of molding the stent input into the personal computer was as shown in FIG. The stent formed body thus produced has 12 annular units, has two connecting portions at positions facing each other between adjacent annular units, and the connecting portions are continuous,
The total length is 20 mm, the outer diameter is 2.0 mm, and the width of the part constituting the wavy element (wavy annular body) and the connecting part is 0.12 m
m, the width of the connection part is 0.12 mm, and the width of the integrated part is
The thickness was 0.12 mm, the length was 0.1 mm, and the total thickness of the stent was about 0.08 mm. Then, this stent formed body is fitted on the balloon portion of a dilatation catheter (balloon catheter) for PTCA, inserted into a mounting device, and the stent is uniformly compressed from the outer surface of the stent toward the center to have an outer diameter of 1.0 mm. Then, it was fitted in a balloon shape to produce a living organ dilator.

(Example 2) Stainless steel (SUS316)
L) having a diameter of 2.0 mm and a wall thickness of 0.095 mm,
A metal pipe cut to a length of 50 mm was used. As a laser processing machine, NEC's YAG laser (trade name S
L116E) was used. The metal pipe was set on a jig with a rotary motor equipped with a chuck mechanism so that the shaft did not move, and this was set on an XY table capable of numerical control. Then, the XY table and the rotary motor were connected to a personal computer, and the output of the personal computer was input to the numerical controller and the rotary motor of the XY table. Drawing software is stored in the personal computer, and here, a developed drawing of the stent in the composition at the time of molding shown in FIG. 6 was input. With such a configuration, the XY table and the rotary motor are driven based on the drawing data output from the personal computer, and a laser is irradiated to the XY table and the stent structure is manufactured. Laser processing conditions for the metal pipe were a current value of 25 A, an output of 1.5 W and a driving speed of 10 mm / min. Then, the prepared stent structure is subjected to a chemical polishing solution for stainless steel (trade name: Sunbit 505, manufactured by Sanshin Chemical Industry Co., Ltd.).
A mixture of hydrochloric acid and nitric acid as a basic component, to which an organic sulfur compound and a surfactant are added) is heated at about 98 ° C. for about 10 minutes, and chamfered (burr removal, chemical polishing). Was.

In this way, a stent formed body was manufactured. The number of annular units in the manufactured stent formed body is 6, and two connecting portions are provided at positions facing each other between adjacent annular units, and the axial displacement of the stent at the connecting portions is about 6
0 degree, the number of substantially polygonal linear bodies constituting the annular unit is 6, the shape is substantially rhombic, and the length of the long axis is 2.6 m
m, the short axis is 0.9 mm, the total length of the stent in the axial direction is 20 mm, and the length of the connecting portion connecting the components in the circumferential direction is 0.35 mm, and the annular units are connected. The length of the connecting part is 0.7 mm and the width is 0.15 m
m. The width of the linear body of the substantially polygonal linear body is 0.2
mm, and the outer diameter of the stent (annular unit) is 2.
It was 0 mm.

Then, this stent-formed body is fitted on the balloon portion of a dilatation catheter (balloon catheter) for PTCA, inserted into a mounting device, and the stent is uniformly compressed from the outer surface to the center of the stent to obtain an outer diameter. 1.0m
m and mounted in a balloon shape to produce a living organ dilator of the present invention having a structure as shown in FIGS. 7 to 9.

(Experiment) An X-ray contrast medium was pressed into the balloon lumen of the living organ dilator of Examples 1 and 2 and Comparative Examples 1 and ² at a pressure of 10 kg / cm ² to expand the balloon.
The stent was expanded to an outer diameter of 3.0 mm. Remove the expanded stent from the living organ dilator, fix both ends, measure the load (tensile strength) applied to the stent when it is pulled 5 mm horizontally and horizontally, and observe the degree of flexibility in the direction perpendicular to the axis. Was. Table 1 shows the results.

[0059]

[Table 1]

[0060]

The stent for indwelling in a living body according to the present invention is formed in a substantially tubular body, has a diameter for insertion into a body lumen, and is provided with a force that spreads radially from inside the tubular body. Claims 1. A stent which is expandable when expanded, comprising: a first corrugated annular body formed by a corrugated element into an annular shape; and a stent having a peak close to a valley of the first corrugated annular body. A second wavy annular body formed in an annular shape by wavy elements disposed in the axial direction, and a plurality of valleys of the first wavy annular body and ridges of the second wavy annular body connected to each other. A plurality of annular units each including a connecting portion are arranged in the axial direction of the stent, and a connecting portion that connects adjacent annular units at the connecting portion forming portion and that is not continuous in the axial direction of the stent, further comprising: Parts are provided between adjacent annular units. It is provided to be equiangularly arranged substantially with respect to the central axis of the position or the stent each other paddle. For this reason, the stent of the present invention has flexibility in a direction perpendicular to the axial direction, and can well maintain the cylindrical shape of the entire stent against expansion and contraction in the axial direction.

The stent for indwelling in a living body of the present invention
A stent formed in a substantially tubular body, having a diameter for insertion into a body lumen, and expandable when a force that expands radially from inside the tubular body is applied, the stent comprising: An annular unit formed by connecting a plurality of substantially polygonal linear bodies having a large number of linear bends and openings which are expanded when the force spreading in the radial direction is applied by a plurality of connecting portions so as to form an annular shape is a shaft of the stent. A plurality of arranged in the direction, and comprises a connecting portion that connects adjacent annular units at the connecting portion and is not continuous in the axial direction of the stent,
The connecting portions are provided so as to be arranged at a plurality of opposed positions between adjacent annular units or substantially equiangularly with respect to the central axis of the stent. For this reason, the stent of the present invention has flexibility in a direction perpendicular to the axial direction, and can well maintain the cylindrical shape of the entire stent against expansion and contraction in the axial direction.

[Brief description of the drawings]

FIG. 1 is a front view of one embodiment of the stent of the present invention.

FIG. 2 is a partially enlarged view of the stent shown in FIG. 1;

FIG. 3 is a development view of the stent shown in FIG. 1;

FIG. 4 is a front view of a stent according to another embodiment of the present invention.

FIG. 5 is a partially enlarged view of the stent shown in FIG. 4;

FIG. 6 is a developed view of the stent shown in FIG. 4;

FIG. 7 is a front view of the living organ dilator according to the present invention.

FIG. 8 is an enlarged partial cross-sectional view of a distal end portion of the living organ dilator shown in FIG. 7;

FIG. 9 is an enlarged cross-sectional view of a rear end portion of the living organ dilator shown in FIG. 7;

FIG. 10 is a development view of a stent of a comparative example.

FIG. 11 is a development view of a stent of another comparative example.

[Explanation of symbols]

 1,10 stent 4 annular unit

Claims (14)

[Claims] 1. A stent formed in a substantially tubular body, having a diameter for insertion into a body lumen, and expandable upon application of a force that extends radially from inside the tubular body. The stent comprises a first wavy annular body formed in an annular shape by the wavy element, and a wavy element arranged in the axial direction of the stent such that a peak is close to a valley of the first wavy annular body. A second wavy annular body formed in an annular shape;
A plurality of annular units each including a plurality of connecting portions for connecting the valleys of the wavy annular body and the ridges of the second wavy annular body are arranged in the axial direction of the stent, and the adjacent annular units are connected to each other. A connecting portion that is connected at the portion forming portion and that is not continuous in the axial direction of the stent, and that the connecting portion is disposed at a plurality of opposed positions between the adjacent annular units or substantially equiangular with respect to the central axis of the stent. A stent for indwelling in a living body, characterized in that the stent is provided so that: 2. An integrated unit in which at least one of the plurality of connecting portions of the annular unit is formed by integrating a valley of the first wavy annular body and a crest of the second wavy annular body. The other connection part is a thin wire connection part.
2. The stent for indwelling in a living body according to item 1. 3. At least one of the plurality of connecting portions provided between the adjacent annular units connects the integrated portions of the adjacent annular units to each other, and the other connecting portion includes the adjacent connecting portion. 3. The stent for indwelling in a living body according to claim 2, wherein the thin line-shaped connecting portion forming portions of the matching annular units are connected to each other. 4. The connecting portion is inclined at a predetermined angle with respect to a central axis of the stent, and connecting portions adjacent to each other in the axial direction of the stent have different inclination directions. 4. The stent for indwelling in a living body according to any one of 1 to 3 above. 5. The connecting portion and the connecting portion which is adjacent to the connecting portion and the stent in the axial direction are displaced by a predetermined angle with respect to the central axis of the stent, and are arranged so that the connecting portion has an intermittent spiral shape. The stent for indwelling in a living body according to any one of claims 1 to 4, wherein the stent is used. 6. The plurality of connecting portions, and the plurality of connecting portions and a plurality of connecting portions which are adjacent in the axial direction of the stent are shifted by a predetermined angle with respect to a central axis of the stent, and the plurality of connecting portions are intermittent. The stent for indwelling in a living body according to any one of claims 1 to 4, wherein the stent is arranged so as to have a spiral shape. 7. The plurality of connection portions are disposed at positions facing each other, and the plurality of connection portions and the plurality of connection portions adjacent in the axial direction of the stent are at an angle of about 60 degrees with respect to the central axis of the stent. The stent for indwelling in a living body according to any one of claims 1 to 4, wherein the stent is arranged so as to be displaced and have a plurality of intermittent spiral shapes. 8. A stent formed in a generally tubular body, having a diameter for insertion into a body lumen, and expandable when a force is applied that extends radially from inside the tubular body. The stent is formed by connecting a plurality of substantially polygonal linear bodies having a large number of linear bent portions and openings extending when the radially expanding force is applied by a plurality of connecting portions so as to form a circular shape. A plurality of units are arranged in the axial direction of the stent, and further include a connecting portion that connects adjacent annular units at the connecting portion and is not continuous in the axial direction of the stent, and further includes a connecting portion between the adjacent annular units. A stent for indwelling in a living body, wherein the stent is provided so as to be arranged at a plurality of positions facing each other or at substantially the same angle with respect to the central axis of the stent. 9. The connecting portion is inclined at a predetermined angle with respect to a central axis of the stent, and connecting portions adjacent to each other in the axial direction of the stent have different inclination directions. 9. The stent for indwelling in a living body according to 8. 10. The connecting portion and the connecting portion which is adjacent to the connecting portion and the stent in the axial direction are arranged so as to be shifted by a predetermined angle with respect to the central axis of the stent, and to have a spiral shape in which the connecting portion is intermittent. The stent for indwelling in a living body according to claim 8 or 9, wherein the stent is used. 11. The plurality of connecting portions and the plurality of connecting portions and a plurality of connecting portions which are adjacent to each other in the axial direction of the stent are shifted by a predetermined angle with respect to a central axis of the stent, and the plurality of connecting portions are intermittent. The stent for indwelling in a living body according to claim 8, wherein the stent is arranged so as to have a spiral shape. 12. The plurality of connecting portions are disposed at positions facing each other, and the plurality of connecting portions and the plurality of connecting portions adjacent in the axial direction of the stent are arranged at about 60 degrees with respect to the central axis of the stent. 10. The connecting part is arranged so as to be shifted and to have a plurality of intermittent spirals.
2. The stent for indwelling in a living body according to item 1. 13. The in-vivo indwelling body according to claim 1, wherein a wavy end of the adjacent annular unit intrudes into a space formed between adjacent wavy elements of the annular unit. Stent. 14. A tubular shaft main body, a foldable and expandable balloon provided at a distal end of the shaft main body, and mounted so as to cover the balloon in a folded state, and A living organ dilator comprising a stent that is expanded by expanding a balloon, wherein the stent is the stent according to any one of claims 1 to 13.