JP2005110778A - Stent and stent graft - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a stent and a stent graft facilitating insertion work into a sheath or the like by appropriately deflecting a wire rod and easily adjusting the length at an operation site. <P>SOLUTION: The wire rod 210 is made to advance while bending to the left/right along the circumferential direction, when there is a crossing portion 230, forms a weave and runs the circle, at least, twice to form a circumferential unit 221. After forming the single circumferential unit, the wire rod 210 is axially moved to form a circumferential unit 222 in a position adjacent to the previously formed circumferential unit in the same way as before, and the wire rods are entangled with each other in folds of the adjoining circumferential units to form an assembled part 240. The wire rods form overlapped parts 250 when the wire rods are axially moved, so that joint parts 260 are formed in the overlapped parts. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a stent and a stent graft that are prevented from stenosis or occlusion of a tubular organ, rupture of an aneurysm, etc. by being placed in a tubular organ in the body such as a biliary tract, a blood vessel, an esophagus, or a trachea.

  Various stents formed by knitting a metal wire having elasticity into a cylindrical shape have been proposed. For example, the following Patent Document 1 includes a continuous elastic knitting line, both ends have a knitting line folding point, and a spiral line wound from one end and the other end folding. There is disclosed a luminal stent characterized in that a knitted wire spirally wound from a point intersects by periodically changing the upper and lower positions of the knitted wire.

  Further, in Patent Document 2 below, in the stent for body cavity expansion composed of a single-length filament formed from a cylindrical shape having a large number of zigzag bands, the band includes a large number of straight portions, peak portions, and valley shapes. The peak portion and the valley portion are arranged in the circumferential direction of the stent and on the same plane, and the peak portion of the adjacent lower band is twisted in the valley portion forming the band. A stent for expanding a body cavity is disclosed in which the filaments of the adjacent lower bands are filaments that extend downward from the straight end portion of the adjacent bands.

Further, in Patent Document 3 below, a shape memory alloy wire is wound in a zigzag pattern along the outer periphery of the mandrel, and when one hoop is formed, it moves in the axial direction along the axis of the mandrel. Then, the next continuous hoop is formed, and after winding the wire in a cylindrical shape along the outer periphery of the mandrel, annealing is performed at a high temperature, and the apexes of each hoop are fixed with polypropylene filaments to form a stent. It is described to do.
JP-A-9-173469 JP-A-10-272190 JP-T 9-511160

  However, in the stent described in the above-mentioned Patent Document 1, it is considered that the knitted wires are likely to be misaligned because they are formed by crossing the spirally wound knitted wires.

  Further, in the stent described in Patent Document 2, it is considered that the peak portions of the adjacent lower band are connected to the valley-shaped portion forming the upper band by the twist method, so that the wires are not easily displaced.

  Furthermore, in the stent described in Patent Document 3, it is considered that the vertices of the respective hoops are fixed with polypropylene filaments, so that the wires are not easily displaced.

  If the stent wires tend to be misaligned, the stent may be reduced in diameter and inserted into the sheath, and the wires may be biased and difficult to insert. Also, if the wires are not easily misaligned, it may be difficult to reduce the diameter. there were.

  Also, in actual surgery, it may be necessary to adjust the length of the stent on the spot according to the condition of the patient's treatment site, but for conventional stents, the length can be easily changed. I could not.

  Accordingly, it is an object of the present invention to provide a stent and a stent graft in which the wire is appropriately displaced, the insertion operation into a sheath or the like is easy, and the length can be easily adjusted at a surgical site or the like. is there.

In order to achieve the above object, a first aspect of the present invention is a stent formed by braiding one or more wires into a cylindrical shape,
The wire rod is advanced while being folded back to the left and right along the circumferential direction, and in the case of crossing, forming a weave, forming a circumferential unit by at least two rounds,
After forming one circumferential unit, the wire is moved in the axial direction to form a circumferential unit at the position adjacent to the previously formed circumferential unit, and adjacent circumferential direction A plurality of circumferential units are knitted by connecting them in the axial direction by interlacing the wires with each other at the folded part between the units,
When the wire is moved in the axial direction, a portion where the wire is overlapped is formed, and joint portions are provided at a plurality of locations including at least a knitting start portion and a knitting end portion of the wire in the portion where the wire is overlapped. A stent characterized by the above is provided.

  According to the stent of the present invention, since it has a portion assembled between the circumferential units and a joint portion in a portion where the wire overlaps, the wire is kept in a certain positional relationship while being moderately maintained. Can shift. As a result, when the diameter is reduced and accommodated in a sheath or the like, the wire does not become unevenly inserted and it is difficult to reduce the diameter, and shape conformability in the tubular organ is also improved.

  In addition, the stent can be easily divided in the axial direction by cutting one part where the wire overlaps and extracting the wire constituting the circumferential unit of the cut part. The length of the stent can be adjusted to a length corresponding to the treatment site of the patient.

  A second aspect of the present invention is the stent according to the first aspect, wherein the wire is formed by braiding the wire in the same direction along the circumferential direction, and a portion where the wires overlap is formed in a spiral shape. Is to provide.

  According to the above invention, since the portion where the wires are overlapped and the rigidity is increased is formed in a spiral shape, linearity in the axial direction is imparted to the entire stent.

  According to a third aspect of the present invention, in the first aspect, after forming the circumferential unit while the wire is advanced in one direction along the circumferential direction, the wire is moved in the axial direction and formed first. A stent in which a wire is advanced in a direction opposite to the circumferential unit to form a next circumferential unit, and the portion where the wires overlap is formed in a zigzag shape along the axial direction. It is to provide.

  According to the above invention, since the overlapping portion of the wire is formed in a zigzag shape along the axial direction, the highly rigid portion is formed like a spine along the axial direction of the stent. A directionality can be imparted to the ease, thereby imparting a characteristic that easily adapts to the treatment site.

  According to a fourth aspect of the present invention, in the first aspect of the present invention, the wire rod is advanced along the circumferential direction to make one round, and then the second round is advanced in the opposite direction to make one round. A circumferential unit is formed, and then the wire is moved in the axial direction to travel in the same direction as the traveling direction of the second round of the previously formed circumferential unit to make one round, and then the opposite direction The stent is braided by repeating the operation of forming the next circumferential unit by making it go around once, and the portion where the wires overlap is formed in a zigzag shape along the axial direction. It is to provide.

  Also in the above-described invention, since the highly rigid portion is formed like a spine along the axial direction of the stent, the directionality is given to the bendability of the stent, thereby easily adapting to the treatment site. Can be granted.

  According to a fifth aspect of the present invention, in the first aspect of the present invention, the wire rod is advanced along the circumferential direction to make one round, and then the second round is advanced in the opposite direction to make one round. A circumferential unit is formed, and then the wire is moved in the axial direction to travel in the opposite direction to the traveling direction of the second round of the previously formed circumferential unit to make one round, and then in the opposite direction The stent is braided by repeating the operation of forming the next circumferential unit by making it go around once, and the portion where the wires overlap is formed in a zigzag shape along the axial direction. It is to provide.

  Also in the above-described invention, since the highly rigid portion is formed like a spine along the axial direction of the stent, the directionality is given to the bendability of the stent, thereby easily adapting to the treatment site. Can be granted.

  A sixth aspect of the present invention provides the stent according to any one of the first to fifth aspects, wherein the stent is formed so as to form a zigzag pattern when the wire is advanced while being folded back to the left and right along the circumferential direction. To do.

  According to the above invention, an intersection is formed between the folded portions of the wire, for example, where the first and second wires cross in a cross shape, and the wire is easily displaced due to the large number of intersections. The degree can be increased.

  A seventh aspect of the present invention is the method according to any one of the first to fifth aspects, wherein the upper side and both side sides of the trapezoid are made continuous when the wire is advanced while being folded back left and right along the circumferential direction. Thus, a stent formed by proceeding as described above is provided.

  According to the above invention, it is possible to form a shape in which three wire rods are combined and knitted at the corners of the trapezoidal pattern, and the wire rods are less likely to be displaced due to the large number of combined portions, thus improving the shape restoration property. be able to.

  In addition, when three wire rods are combined at the corners of the trapezoidal pattern, by connecting the sides of the trapezoid to each other, the corners bent into a V shape are directed toward the outer periphery of the stent, When the stent is bent, the corners of the wire can be prevented from protruding to the inner periphery of the stent.

  According to an eighth aspect of the present invention, there is provided a stent graft comprising the stent according to any one of the first to seventh aspects of the present invention and a graft covering the inner periphery and / or outer periphery of the stent.

  According to the above invention, it is possible to provide a stent graft that can be easily reduced in diameter and inserted into a sheath or the like, and whose length can be adjusted by dividing the stent in the axial direction as necessary.

  The stent of the present invention can be appropriately displaced while maintaining a predetermined positional relationship between the wires, so that it can be easily inserted into a sheath or the like with a reduced diameter, and the shape conformity in the tubular organ is also good. . Further, the length can be adjusted by dividing in the axial direction as necessary. Furthermore, by setting the overlapping portions of the wire materials in accordance with the purpose, it is possible to provide characteristics such as a direction in which the wire is easily bent. Therefore, by using the stent and stent graft of the present invention, it is possible to easily and accurately perform the operation of inserting the stent or stent graft into the tubular organ.

1 to 6 show a stent graft according to a first embodiment of the present invention.
As shown in FIGS. 1 and 2, the stent graft 100 is configured by covering the outer periphery of a stent 200 formed by braiding a wire material 210 into a cylindrical shape with a graft 300 that is a cylindrical cover. The graft 300 may be coated on the inner periphery of the stent 200, or may be coated on both the inner periphery and the outer periphery.

  As a material of the wire 210 forming the stent 200, a metal wire is preferable, and in particular, a shape memory alloy imparted with a shape memory effect and superelasticity by heat treatment is preferably employed. However, stainless steel, tantalum, titanium, platinum, gold, tungsten, or the like may be used depending on the application. As the shape memory alloy, Ni—Ti, Cu—Al—Ni, Cu—Zn—Al, and the like are preferably used. Further, the surface of the metal wire may be coated with gold, platinum or the like by means such as plating. Although the thickness of a metal wire is not specifically limited, For example, in the case of a blood vessel stent etc., 0.08-1 mm is preferable. Note that a synthetic resin fiber or the like can also be used as the wire 210.

  As the graft 300, a thermoplastic resin formed into a cylindrical shape processed by a molding method such as extrusion molding or blow molding, a knitted fabric of thermoplastic resin fibers formed into a cylindrical shape, or a thermoplastic resin formed into a cylindrical shape. A resin non-woven fabric, a flexible resin sheet formed in a cylindrical shape, a porous sheet, or the like can be used. As the knitted fabric, known knitted fabrics and woven fabrics such as plain weave and twill weave can be used. Moreover, the thing with a crimp, such as crimping, can also be used.

  Among these, as the graft 300, in particular, a knitted fabric of thermoplastic resin fibers formed in a cylindrical shape, and a plain woven fabric of thermoplastic resin fibers formed in a cylindrical shape, strength, porosity, productivity Is preferable because it is excellent.

  Examples of the thermoplastic resin include polyolefins such as polyethylene, polypropylene, and ethylene-α-olefin copolymers, polyamides, polyurethanes, polyethylene terephthalates, polybutylene terephthalates, polycyclohexane terephthalates, polyesters such as polyethylene-2,6-naphthalate, poly A resin having a low durability and a tissue reaction such as a fluororesin such as fluorinated ethylene or polyfluorinated propylene can be used.

  In particular, polyesters such as polyethylene terephthalate, fluorine resins such as polyfluorinated ethylene and polyfluorinated propylene, which are chemically stable and have high durability and little tissue reaction, can be preferably used.

  As the graft 300, the fibers constituting the graft, and the wire 210 constituting the stent 200, those coated with an antithrombotic material such as haparin, collagen, acetylsalicylic acid, and gelatin can be used.

  The graft 300 is connected to the stent 200 by means such as sewing, adhesion, and welding. In this case, the graft 300 needs to be covered and connected so as not to affect the expansion and contraction of the stent 200. The connecting portion between the graft 300 and the stent 200 can be appropriately provided at both end portions or an intermediate portion of the stent 200. Although the entire graft 300 may be connected to the stent 200 at a predetermined interval, only the both ends of the graft 300 and the stent 200 or only one end of the graft 300 and the stent 200 may be connected. In particular, as will be described later, when the stent 200 is divided in the axial direction, the graft 300 and the stent 200 are connected to each other only at one end, and the graft 300 is connected to the stent 200 like a blow-off. It is preferable that

  The stent graft 100 of the present invention preferably has an outer diameter of 2 to 50 mm and a length of about 1 to 50 cm when expanded.

  Further, an X-ray opaque material may be fixed to an appropriate place of the stent 200, for example, at both ends. As the X-ray opaque material, for example, gold, platinum, iridium, tantalum, tungsten, silver, or an alloy containing them is preferably used. The radiopaque material can be fixed to the stent 200 by means of soldering, brazing, welding, adhesion, caulking, or the like.

  As shown in FIG. 3, the stent 200 is formed by knitting a wire 210 in the procedure shown by an arrow in the drawing. The knitting operation can be performed while winding the wire 210 in a predetermined pattern around the outer periphery of a mandrel (not shown).

  That is, along the circumferential direction of the mandrel, the wire 210 is advanced in a zigzag pattern while being folded back to the left and right to form the first loop 211.

  When the wire 210 has made one round, the loop 212 is formed so as to form a zigzag pattern while folding back left and right in the same direction. At that time, in the portion 230 that intersects with the loop 211 of the first round, the upper and lower portions of the loop 211 are alternately passed so as to form a weave. By forming the second loop 212 in this way, the first circumferential pattern 221 is formed.

  After forming the first circumferential pattern 221, the wire 210 is moved in the axial direction so that a zigzag pattern is formed while folding back left and right along the circumferential direction at a position adjacent to the first circumferential pattern 221. The third loop 213 is formed in the same direction as the loops 211 and 212. At that time, the assembled portion 240 is formed by entwining the wire 210 at the folded portion of the first circumferential pattern 221.

  In the present invention, it is preferable that the assembly portion 240 is formed by hooking the wire rods 210 only once, thereby allowing the shift without allowing the wire rods 210 to be fixed and allowing flexibility and shape conformity. Can be increased.

  After forming the third loop 213, the fourth loop 214 is formed at the same position. The loop 214 on the fourth turn alternately passes above and below the loop 213 so as to form a weave at a portion 230 intersecting with the loop 213 on the third turn. Further, the assembled portion 240 is formed by being entangled with the folded portion of the first circumferential pattern 221.

  Thus, the second circumferential pattern 222 connected in the axial direction of the first circumferential pattern 221 is formed by the loop 213 on the third circumference and the loop 214 on the fourth circumference.

  After forming the loop 214 of the fourth circumference, the wire 210 is moved in the axial direction, and at the position adjacent to the second circumferential pattern 222, the zigzag pattern is formed while folding back left and right along the circumferential direction. Advancing in the same direction as the loops 211 to 214, a fifth loop 215 is formed. At this time, the assembled portion 240 is formed by entwining the wire 210 at the folded portion of the second circumferential pattern 222.

  After forming the fifth loop 215, the sixth loop 216 is formed at the same position. The loop 216 on the sixth turn alternately passes above and below the loop 213 so as to form a weave at a portion 230 intersecting with the loop 215 on the fifth turn. Further, the assembled portion 240 is formed by being entangled with the folded portion of the first circumferential pattern 221.

  Thus, the third circumferential pattern 223 connected in the axial direction of the second circumferential pattern 222 is formed by the loop 215 on the fifth circumference and the loop 216 on the sixth circumference.

  In the same manner, by sequentially forming the fourth circumferential pattern 224, the fifth circumferential pattern 225, the sixth circumferential pattern 226, etc., and selecting the number of circumferential patterns connected in the axial direction, A stent 200 having a desired length can be obtained.

  In the stent 200 thus obtained, a portion 250 in which two wires 210 overlap each other is formed in a spiral shape. And in this invention, the junction part 260 which binds the overlapped wire 210 is formed in the multiple places of this overlapping part 250. In FIG. The joint 260 can be formed by, for example, a method of binding with a synthetic resin thread or wire, fixing with an adhesive, or brazing. The joining portion 260 has essential ends of the winding start and end of the wire 210, and can be provided at an intermediate portion as necessary. It is preferable to provide the joint portion 260 in the assembled portion 240 on the overlapping portion 250 of the wire material, in addition to the winding wire end portion and the winding end portion.

  As shown in FIGS. 1 and 2, this stent 200 has a wire 210 knitted in a cylindrical shape with the above structure, and a portion 250 where two wires 210 overlap each other is formed in a spiral shape. And the said junction part 260 is formed in the multiple places of this overlapped part 250. FIG. The joining portion 260 prevents the wire 210 from being displaced, and the rigidity of the overlapping portion 250 can be increased.

  The portion 250 in which the two wires 210 overlap each other is formed in a spiral shape, so that a highly rigid portion is formed in a spiral shape, and the rigidity that enhances the linearity of the stent 200 in the axial direction. Is granted. As a result, when the straight state of FIG. 5A is changed to the bent state of FIG. 5B, the stent 200 is bent on average as a whole.

  In addition, as shown in FIG. 4A, when the stent 200 is cut at one place A where the two wires 210 overlap each other, as shown in FIG. 4B, the cut place A belongs. The wire 210 of the circumferential pattern 222 can be extracted, thereby dividing the portion made of the circumferential pattern 221 and the portion made of the circumferential patterns 223 to 226. In FIG. 4 (b), the cutting steps a1 and a2 and the cutting ends b1 and b2 are connected to each other. In addition, it is preferable to join the edge part of the cut | disconnected wire 210 by the method similar to the above.

  In addition, when the length of the stent 200 is changed, it is preferable to adjust the length of the graft 300 in FIG. For this reason, it is preferable that the graft 300 is connected to only one end portion of the stent 200 and connected to the stent 200 like a windsock.

  The stent graft 100 is inserted into a tubular organ in the body through a catheter or the like (not shown). FIG. 6 shows a state in which the aneurysm C is treated by being inserted into the inner periphery of the aneurysm C of the blood vessel B. That is, by disposing the stent graft 100 so as to cover the inner circumference of the aneurysm C of the blood vessel B, blood flows through the inner circumference of the stent graft 100 and does not flow into the aneurysm C, thereby avoiding the danger caused by the aneurysm C. be able to.

  7 and 8 show a stent according to a second embodiment of the present invention. The stent 201 is different from the stent 200 in the first embodiment in the knitting pattern of the wire 210 as follows.

  That is, as shown in FIG. 7, in the circumferential direction of a mandrel (not shown), the wire 210 is advanced in a zigzag pattern while being folded back to the left and right to form the first loop 211. When the wire 210 has made one round, the loop 212 is formed so as to form a zigzag pattern while folding back left and right in the same direction. At that time, in the portion 230 that intersects with the loop 211 of the first round, the upper and lower portions of the loop 211 are alternately passed so as to form a weave. By forming the second loop 212 in this way, the first circumferential pattern 221 is formed.

  After forming the first circumferential pattern 221, the wire 210 is moved in the axial direction. At that time, as shown by an arrow D in FIG. 7, the wire 210 is reversed to reverse the traveling direction. Then, at the position adjacent to the first circumferential pattern 221, the loop 213 for the third round is formed while forming the assembly 240 with respect to the first circumferential pattern 221, as in the first embodiment. Then, a loop 214 of the fourth turn is formed. Thus, the second circumferential pattern 222 connected in the axial direction of the first circumferential pattern 221 is formed by the loop 213 on the third circumference and the loop 214 on the fourth circumference.

  After forming the loop 214 of the fourth turn, the wire 210 is moved in the axial direction. At that time, as shown by an arrow E in FIG. 7, the wire 210 is reversed again to reverse the traveling direction. Then, at a position adjacent to the second circumferential pattern 222, it is advanced so as to form a zigzag pattern while being folded back to the left and right along the circumferential direction, thereby forming a loop 215 for the fifth cycle and a loop 216 for the sixth week. . Thus, the third circumferential pattern 223 connected in the axial direction of the second circumferential pattern 222 is formed by the loop 215 on the fifth circumference and the loop 216 on the sixth circumference.

  In the same manner, by sequentially forming the fourth circumferential pattern 224, the fifth circumferential pattern 225, the sixth circumferential pattern 226, etc., and selecting the number of circumferential patterns connected in the axial direction, A stent 201 having a desired length can be obtained.

  In this embodiment, the portion 250 where the wire 210 overlaps is formed in a zigzag shape along the axial direction of the stent 201. And the junction part 260 is formed in the several location on the part 250 with which the wire 210 overlapped. In the case of this embodiment, the joint portion 260 is formed at the beginning and end of winding of the wire 210 at both ends of the stent 201 and the assembled portion 240 in the second to fifth circumferential patterns 222 to 225.

  In this stent 201, a portion 250 where the wires 210 overlap each other is formed like a spine along the axial direction, and the portion where the joint 260 is formed is particularly high in rigidity. As a result, as shown in FIG. 8B, when the stent 201 is bent downward with the overlapping portion 250 of the wire 210, the portion where the joint portion 260 is large is difficult to bend and the portion where the joint portion 260 is small Becomes easier to bend.

  Further, when the portion 250 where the wire 210 is overlapped is bent outward, it is easy to bend, but when the portion 250 where the wire 210 is overlapped is bent inside, it is difficult to bend. Thus, since the directionality is brought about in the ease of bending, it is possible to impart bending characteristics that are more easily adapted according to the treatment site of the tubular organ to be applied.

  Further, as in the first embodiment, the stent 201 may be divided in the circumferential direction by cutting one portion of the portion 250 where the wire 210 overlaps and extracting the wire 210 in the circumferential pattern at the cut portion. it can.

  FIG. 9 shows a stent according to a third embodiment of the present invention. The stent 202 differs from the stent 200 in the first embodiment in the knitting pattern of the wire 210 as follows.

  That is, in the circumferential direction of a mandrel (not shown), the wire 210 is moved back and forth so as to form a zigzag pattern, and the first loop 211 is formed. When the wire 210 goes around, as shown by an arrow F in FIG. 9, the wire 210 is reversed and advanced in a zigzag pattern while turning left and right in the opposite direction along the circumferential direction. A circumferential loop 212 is formed. At that time, in the portion 230 that intersects with the loop 211 of the first round, the upper and lower portions of the loop 211 are alternately passed so as to form a weave. By forming the second loop 212 in this way, the first circumferential pattern 221 is formed.

  After forming the first circumferential pattern 221, the wire 210 is moved in the axial direction. Then, at the position adjacent to the first circumferential pattern 221, the loop 213 for the third round is formed while forming the assembled portion 240 with respect to the first circumferential pattern 221. When the third loop 213 is formed, as shown by an arrow G in FIG. 9, the wire 210 is reversed again so as to form a zigzag pattern while turning back and forth in the opposite direction along the circumferential direction. The loop 214 of the 4th round is formed by making it advance. Thus, the second circumferential pattern 222 connected in the axial direction of the first circumferential pattern 221 is formed by the loop 213 on the third circumference and the loop 214 on the fourth circumference.

  In the same manner, a third circumferential pattern 223, a fourth circumferential pattern 224, a fifth circumferential pattern 225, a sixth circumferential pattern 226, etc. are sequentially formed and connected in the axial direction. By selecting the number, it is possible to obtain the stent 201 having a desired length.

  Also in this embodiment, the portion 250 where the wire 210 overlaps is formed in a zigzag shape along the axial direction of the stent 201. And the junction part 260 is formed in the several location on the part 250 with which the wire 210 overlapped. In the case of this embodiment, the joint 260 is formed at the beginning and end of winding of the wire 210 at both ends of the stent 201.

  FIG. 10 shows a stent according to a fourth embodiment of the present invention. The stent 202 differs from the stent 200 in the first embodiment in the knitting pattern of the wire 210 as follows.

  That is, in the circumferential direction of a mandrel (not shown), the wire 210 is moved back and forth so as to form a zigzag pattern, and the first loop 211 is formed. When the wire 210 goes around, as shown by an arrow H in FIG. 10, the wire 210 is reversed and advanced in a zigzag pattern while turning back left and right in the opposite direction along the circumferential direction. A circumferential loop 212 is formed. At that time, in the portion 230 that intersects with the loop 211 of the first round, the upper and lower portions of the loop 211 are alternately passed so as to form a weave. By forming the second loop 212 in this way, the first circumferential pattern 221 is formed.

  After forming the first circumferential pattern 221, the wire 210 is moved in the axial direction. At that time, the wire 10 is reversed as indicated by an arrow I in FIG. Then, at the position adjacent to the first circumferential pattern 221, the loop 213 for the third round is formed while forming the assembled portion 240 with respect to the first circumferential pattern 221. When the third loop 213 is formed, as shown by an arrow J in FIG. 10, the wire 210 is reversed again so that a zigzag pattern is formed while turning back and forth in the opposite direction along the circumferential direction. The loop 214 of the 4th round is formed by making it advance. Thus, the second circumferential pattern 222 connected in the axial direction of the first circumferential pattern 221 is formed by the loop 213 on the third circumference and the loop 214 on the fourth circumference.

  In the same manner, a third circumferential pattern 223, a fourth circumferential pattern 224, a fifth circumferential pattern 225, a sixth circumferential pattern 226, etc. are sequentially formed and connected in the axial direction. By selecting the number, it is possible to obtain the stent 201 having a desired length.

  Also in this embodiment, the portion 250 where the wire 210 overlaps is formed in a zigzag shape along the axial direction of the stent 201. And the junction part 260 is formed in the several location on the part 250 with which the wire 210 overlapped. In the case of this embodiment, since the zigzag folding width in the portion 250 where the wire 210 overlaps is narrow, the high-rigidity portion is clearly formed in a line shape along the axial direction, so that the bending characteristics are given more clearly. I can.

  FIG. 11 shows a stent according to a fifth embodiment of the present invention. The stent 204 is different in the knitting pattern of the wire 210 from the stent 200 in the first embodiment as follows.

  That is, in this embodiment, when the wire 210 is advanced while being folded back left and right along the circumferential direction, a pattern in which the upper side and both sides of the trapezoid are continuous (hereinafter referred to as “trapezoidal pattern”) is formed. Make it progress. For example, the first loop 211 is formed by advancing the wire 210 along the circumferential direction of the mandrel so as to form the trapezoidal pattern while being folded back left and right.

  When the wire 210 goes around once, it is advanced to form a trapezoidal pattern while being folded back to the left and right in the same direction to form a loop 212 for the second round. At that time, the loop 211 in the first round and the loop 212 in the second round intersect at the corner of the upper side of the trapezoid, but advance so as to alternately pass above and below the loop 211. By forming the second loop 212 in this way, the first circumferential pattern 221 is formed.

  After forming the first circumferential pattern 221, the wire 210 is moved in the axial direction to form a trapezoidal pattern while being folded back left and right along the circumferential direction at a position adjacent to the first circumferential pattern 221. The third loop 213 is formed by proceeding in the same direction as the loops 211 and 212. At that time, the assembled portion 240 is formed by entwining the wire 210 at the folded portion of the first circumferential pattern 221.

  In this assembled portion 240, a point to be noted is that the V-shaped bent portion V of the circumferential pattern formed in front of the assembled portion 240 is entangled so as to be positioned on the outer peripheral side of the stent 202. Thereby, when the stent 202 is bent, the bent portion V can be prevented from projecting to the inner peripheral side of the stent 202.

  After forming the third loop 213, the fourth loop 214 is formed at the same position. The loop 214 of the fourth circumference is also entangled at the folded portion of the first circumferential pattern 221 to form the assembled portion 240. Thus, the second circumferential pattern 222 connected in the axial direction of the first circumferential pattern 221 is formed by the loop 213 on the third circumference and the loop 214 on the fourth circumference.

  In the same manner, a third circumferential pattern 223, a fourth circumferential pattern 224, a fifth circumferential pattern 225, a sixth circumferential pattern 226, etc. are sequentially formed and connected in the axial direction. By selecting the number, it is possible to obtain the stent 201 having a desired length.

  In the stent 201, a portion 250 where the wire 210 is overlapped is formed in a spiral shape, and joint portions 260 for binding the overlapped wire 210 are formed at a plurality of locations of the overlapped portion 250.

  The stent 204 obtained in this way can be formed into a shape in which three wire rods are combined and knitted at the corners of the trapezoidal pattern. Restorability can be improved.

  In this embodiment as well, similarly to the first embodiment, the stent 201 is wound around by cutting one portion of the portion 250 where the wire 210 overlaps and extracting the wire 210 in the circumferential pattern at the cut portion. It can also be divided into directions.

  FIG. 12 shows a stent according to a sixth embodiment of the present invention. The stent 205 is different from the stent 204 in the fifth embodiment in the knitting pattern of the wire 210 as follows.

  That is, in the circumferential direction of a mandrel (not shown), the wire 210 is advanced in a trapezoidal pattern while being folded back left and right to form the first loop 211. When the wire 210 goes around once, it is advanced to form a trapezoidal pattern while being folded back to the left and right in the same direction to form a loop 212 for the second round. By forming the second loop 212 in this way, the first circumferential pattern 221 is formed.

  After forming the first circumferential pattern 221, the wire 210 is moved in the axial direction. At that time, as indicated by an arrow K in FIG. 12, the wire 210 is reversed to reverse the traveling direction. Then, at the position adjacent to the first circumferential pattern 221, the loop 213 for the third round is formed while forming the assembly 240 with respect to the first circumferential pattern 221, as in the first embodiment. Then, a loop 214 of the fourth turn is formed. Thus, the second circumferential pattern 222 connected in the axial direction of the first circumferential pattern 221 is formed by the loop 213 on the third circumference and the loop 214 on the fourth circumference.

  After forming the loop 214 of the fourth turn, the wire 210 is moved in the axial direction. At that time, as indicated by an arrow L in FIG. 12, the wire 210 is reversed again to reverse the traveling direction. Then, at a position adjacent to the second circumferential pattern 222, it proceeds to form a trapezoidal pattern while folding back left and right along the circumferential direction to form a loop 215 for the fifth round and a loop 216 for the sixth week. To do. Thus, the third circumferential pattern 223 connected in the axial direction of the second circumferential pattern 222 is formed by the loop 215 on the fifth circumference and the loop 216 on the sixth circumference.

  In the same manner, by sequentially forming the fourth circumferential pattern 224, the fifth circumferential pattern 225, the sixth circumferential pattern 226, etc., and selecting the number of circumferential patterns connected in the axial direction, A stent 205 having a desired length can be obtained.

  In this embodiment, a portion 250 where the wires 210 overlap is formed in a zigzag shape along the axial direction of the stent 205. And the junction part 260 is formed in the several location on the part 250 with which the wire 210 overlapped.

  FIG. 13 shows a stent according to a seventh embodiment of the present invention. The stent 202 is different in the knitting pattern of the wire 210 from the stent 204 in the fifth embodiment as follows.

  That is, in the circumferential direction of a mandrel (not shown), the wire 210 is advanced in a trapezoidal pattern while being folded back left and right to form the first loop 211. When the wire 210 goes around, as shown by an arrow M in FIG. 13, the wire 210 is reversed and advanced in a zigzag pattern while turning left and right in the opposite direction along the circumferential direction. A circumferential loop 212 is formed. By forming the second loop 212 in this way, the first circumferential pattern 221 is formed.

  After forming the first circumferential pattern 221, the wire 210 is moved in the axial direction. Then, at the position adjacent to the first circumferential pattern 221, the loop 213 for the third round is formed while forming the assembled portion 240 with respect to the first circumferential pattern 221. When the third loop 213 is formed, as shown by the arrow N in FIG. 13, the wire 210 is reversed again so as to form a trapezoidal pattern while turning back and forth in the opposite direction along the circumferential direction. The loop 214 of the 4th round is formed. Thus, the second circumferential pattern 222 connected in the axial direction of the first circumferential pattern 221 is formed by the loop 213 on the third circumference and the loop 214 on the fourth circumference.

  In the same manner, a third circumferential pattern 223, a fourth circumferential pattern 224, a fifth circumferential pattern 225, a sixth circumferential pattern 226, etc. are sequentially formed and connected in the axial direction. By selecting the number, it is possible to obtain the stent 201 having a desired length.

  Also in this embodiment, the portion 250 where the wire 210 overlaps is formed in a zigzag shape along the axial direction of the stent 201. And the junction part 260 is formed in the several location on the part 250 with which the wire 210 overlapped.

  FIG. 14 shows a stent according to an eighth embodiment of the present invention. The stent 202 is different in the knitting pattern of the wire 210 from the stent 204 in the fifth embodiment as follows.

  That is, in the circumferential direction of a mandrel (not shown), the wire 210 is advanced in a trapezoidal pattern while being folded back left and right to form the first loop 211. When the wire 210 goes around, as shown by the arrow O in FIG. 14, the wire 210 is reversed, advanced in the opposite direction along the circumferential direction, and advanced in a trapezoidal pattern while turning back to the left and right, A second loop 212 is formed. By forming the second loop 212 in this way, the first circumferential pattern 221 is formed.

  After forming the first circumferential pattern 221, the wire 210 is moved in the axial direction. At that time, the wire 10 is reversed as indicated by an arrow P in FIG. Then, at the position adjacent to the first circumferential pattern 221, the loop 213 for the third round is formed while forming the assembled portion 240 with respect to the first circumferential pattern 221. When the third loop 213 is formed, as shown by an arrow Q in FIG. 14, the wire 210 is reversed again to form a trapezoidal pattern while turning left and right in the opposite direction along the circumferential direction. The loop 214 of the 4th round is formed. Thus, the second circumferential pattern 222 connected in the axial direction of the first circumferential pattern 221 is formed by the loop 213 on the third circumference and the loop 214 on the fourth circumference.

  In the same manner, a third circumferential pattern 223, a fourth circumferential pattern 224, a fifth circumferential pattern 225, a sixth circumferential pattern 226, etc. are sequentially formed and connected in the axial direction. By selecting the number, it is possible to obtain the stent 201 having a desired length.

  Also in this embodiment, the portion 250 where the wire 210 overlaps is formed in a zigzag shape along the axial direction of the stent 201. And the junction part 260 is formed in the several location on the part 250 with which the wire 210 overlapped.

  In addition, although the said 2nd-8th embodiment is targeting the stent, it can also mount | wear with these stents and can utilize as a stent graft.

  The stent of each of the above embodiments is formed by knitting a single wire. For example, the stent is knitted in parallel while advancing two or more wires, or formed by knitting a single wire. By connecting the stents in the axial direction, a stent knitted with two or more wires may be used.

  INDUSTRIAL APPLICABILITY The present invention is used as a stent and a stent graft that are prevented from stenosis or occlusion of a tubular organ, rupture of an aneurysm, etc. by being placed in a tubular organ in the body such as a biliary tract, blood vessel, esophagus, or trachea Can do.

1 is a partially cutaway perspective view showing a stent graft according to a first embodiment of the present invention. It is a perspective view which shows the stent of the same stent graft. It is an expanded view which shows the knitting pattern of the stent. It is explanatory drawing which shows the method of dividing | segmenting the same stent to an axial direction. It is explanatory drawing which shows the ease of bending of the stent. It is explanatory drawing which shows the state which inserted the stent graft in the blood vessel. It is an expanded view of the knitting pattern which shows the stent by 2nd Embodiment of this invention. It is explanatory drawing which shows the ease of bending of the stent. It is an expanded view of the knitting pattern which shows the stent by 3rd Embodiment of this invention. It is an expanded view of the knitting pattern which shows the stent by 4th Embodiment of this invention. It is an expanded view of the knitting pattern which shows the stent by 5th Embodiment of this invention. It is an expanded view of the knitting pattern which shows the stent by 6th Embodiment of this invention. It is an expanded view of the knitting pattern which shows the stent by 7th Embodiment of this invention. It is an expanded view of the knitting pattern which shows the stent by 8th Embodiment of this invention.

Explanation of symbols

100 Stent graft 200, 201, 202, 203, 204, 205, 206, 207 Stent 210 Wire 211 First loop 212 Second loop 213 Third loop 214 Fourth week loop 215 Fifth loop 216 6 Circumferential loop 221 1st circumferential pattern 222 2nd circumferential pattern 223 3rd circumferential pattern 224 4th circumferential pattern 225 5th circumferential pattern 226 6th circumferential pattern 230 The part which cross | intersects 240 Assembly part 250 Part where wire rods overlap 260 Joint part

Claims (8)

In a stent formed by braiding one or more wires into a cylindrical shape,
The wire rod is advanced while being folded back to the left and right along the circumferential direction, and in the case of crossing, forming a weave, forming a circumferential unit by at least two rounds,
After forming one circumferential unit, the wire is moved in the axial direction to form a circumferential unit at the position adjacent to the previously formed circumferential unit, and adjacent circumferential direction A plurality of circumferential units are knitted by connecting them in the axial direction by interlacing the wires with each other at the folded part between the units,
When the wire is moved in the axial direction, a portion where the wire is overlapped is formed, and joint portions are provided at a plurality of locations including at least a knitting start portion and a knitting end portion of the wire in the portion where the wire is overlapped. A stent characterized by   The stent according to claim 1, wherein the stent is formed by braiding the wire in the same direction along the circumferential direction, and a portion where the wire overlaps is formed in a spiral shape.   After forming the circumferential unit while moving the wire in one direction along the circumferential direction, the wire is moved in the axial direction, and the wire is advanced in the direction opposite to the previously formed circumferential unit. The stent according to claim 1, wherein the stent is braided by forming a next circumferential unit, and a portion where the wires overlap is formed in a zigzag shape along the axial direction.   The wire rod is advanced along the circumferential direction to make one round, and then the second round is advanced in the opposite direction to make one round to form one circumferential unit, and then the wire rod is moved in the axial direction. After moving and traveling in the same direction as the traveling direction of the second round of the previously formed circumferential unit for one round, proceeding in the opposite direction to making one round, the next circumferential unit The stent according to claim 1, wherein the stent is knitted by repeating the operation of forming a wire, and a portion where the wires overlap is formed in a zigzag shape along the axial direction.   The wire rod is advanced along the circumferential direction to make one round, and then the second round is advanced in the opposite direction to make one round to form one circumferential unit, and then the wire rod is moved in the axial direction. After moving and making it travel in the opposite direction to the traveling direction of the second round of the previously formed circumferential unit to make one round, the next circumferential direction unit is made to travel in the opposite direction to make one round. The stent according to claim 1, wherein the stent is braided by repeating the operation of forming a wire, and a portion where the wires overlap is formed in a zigzag shape along the axial direction.   The stent according to any one of claims 1 to 5, wherein the stent is formed so as to form a zigzag pattern when the wire is advanced while being folded back to the left and right along the circumferential direction.   6. The wire rod according to any one of claims 1 to 5, wherein the wire rod is made to advance so as to form a pattern in which the upper side and both sides of the trapezoid are continuous when the wire material is advanced while being folded back to the left and right along the circumferential direction. Stent. A stent graft comprising the stent according to any one of claims 1 to 7 and a graft covering an inner periphery and / or an outer periphery of the stent.

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