Stent connection structure

Abstract

To provide a stent which can be detained at a proper axial length, to a tube axis direction length of a lesioned portion.SOLUTION: There is provided a tubular stent 1 detained in a living body lumen, the stent has: multiple stent parts 11, 21 which can be expanded and shrunk in a radial direction substantially orthogonal to an axial direction. The stent parts 11, 21 are detained in the living body lumen in a state in which facing end parts in the axial direction of the stent parts are overlapped. At least one of the multiple stent parts 11, 21 has a regulation part 2 on a region overlapping the other stent part for regulating axial relative displacement to the other stent part. The end part on one stent part into which the end part of the other stent part is inserted, is inclined so that its outer diameter is shrunk toward a tip end side in the axial direction.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a stent. [Background technology]

[0002] Conventionally, stents have been known that are placed at lesions such as stenoses or obstructions that occur in biological lumens, including blood vessels, the esophagus, the bile duct, the trachea, the ureter, etc., and that expand the diameter of the lesion to maintain the patency of the biological lumen (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 4651943 Summary of the Invention [Problem to be solved by the invention]

[0004] The stents disclosed in Patent Document 1 and elsewhere have a single, elongated structure in the axial direction. Therefore, in stent placement, a stent having an axial length close to the axial length of the lesion site in the biological lumen is selected and placed.

[0005] However, if a stent longer than necessary is placed relative to the axial length of the lesion, an excess stent portion will be present that does not directly function to treat the lesion, and this excess stent portion may interfere with the normal function of the biological lumen or may lead to complications such as perforation. If the axial length of the stent is insufficient compared to the axial length of the lesion site, an additional stent must be placed.

[0006] The present invention has been made in view of the above circumstances, and has as its object to provide a stent that can be placed with an axial length that is appropriate for the axial length of the lesion site. [Means for solving the problem]

[0007] One aspect of the present invention is a cylindrical stent to be placed in a biological lumen, comprising a plurality of stent sections that are expandable and contractable in a radial direction substantially perpendicular to the axial direction. The plurality of stent sections are placed in the biological lumen with their opposing axial ends overlapping each other. At least one of the plurality of stent sections has a restricting section in an area where it overlaps with the other stent section, which restricts relative axial displacement with respect to the other stent section. The end of one stent section, into which the end of the other stent section is inserted, is inclined so that its outer diameter decreases toward the distal end in the axial direction. Another aspect of the present invention is a cylindrical stent to be placed in a biological lumen, comprising a plurality of stent sections that are expandable and contractable in a radial direction substantially perpendicular to the axial direction. The plurality of stent sections are placed in the biological lumen with their opposing axial ends overlapping each other. At least one of the plurality of stent sections has a restricting section in an area overlapping the other stent section that restricts relative axial displacement with respect to the other stent section. The end of the other stent section that is inserted into the end of the one stent section is inclined so that its outer diameter expands toward the distal end in the axial direction. [Effects of the Invention]

[0008] According to the present invention, it is possible to provide a stent that can be placed with an axial length that is appropriate for the axial length of the lesion site. [Brief explanation of the drawings]

[0009] [Figure 1] 1A and 1B are diagrams showing an example of the configuration of a stent according to an embodiment of the present invention. [Figure 2] FIG. 1(b) is a perspective view of FIG. [Figure 3] FIG. 1 is a diagram schematically illustrating a state in which a stent is placed in a biological lumen. [Figure 4] FIG. 2 is a diagram showing a reduced diameter portion and an expanded diameter portion. [Figure 5] FIG. 1 is a diagram showing an example of a placement device used for placing a stent according to this embodiment. [Figure 6]10A and 10B are diagrams illustrating other examples of the restricting portion. [Figure 7] 10A and 10B are diagrams illustrating other examples of the restricting portion. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, examples of the configuration of a stent according to an embodiment of the present invention will be described with reference to the drawings. Here, the shapes, dimensions, etc. of each part in the drawings are shown schematically and do not represent the actual shapes, dimensions, etc. In the drawings, the axial direction Ax of the member is indicated by an arrow as needed. Also, the direction approximately perpendicular to the axial direction Ax is defined as the radial direction. In the drawings, one end side of the member is indicated by the symbol F as needed, and the other end side opposite to the one end side is indicated by the symbol B as needed.

[0011] Figures 1(a) and 1(b) are diagrams showing an example of the configuration of a stent 1 of this embodiment. Figure 2 is a perspective view of Figure 1(b). Figure 3 is a diagram showing a schematic diagram of the stent 1 placed in a biological lumen. Although Figures 1 and 2 show the stent 1 having a straight cylindrical shape, the shape of the stent 1 may be, for example, curved in an arched shape or twisted.

[0012] The stent 1 of this embodiment is placed in a lesion such as a narrowed or obstructed area in a biological lumen such as a blood vessel, esophagus, bile duct, trachea, or ureter, and is used to expand the lesion. Fig. 3 shows an example in which the stent 1 is placed in a lesion 3a in the digestive tract 3 (for example, the horizontal part of the duodenum) as an example of a biological lumen. Note that the stent 1 is not limited to being placed in the digestive tract 3, and may be placed in other biological lumens.

[0013] As shown in FIG. 1( a), the stent 1 of this embodiment has a first stent section 11 arranged at one end and a second stent section 21 arranged at the other end. When the stent 1 is placed, as shown in FIGS. 1( b) and 2, the first stent section 11 and the second stent section 21 are aligned in the axial direction, with an area OA formed where the end 11a at the other end of the first stent section 11 and the end 21a at one end of the second stent section 21 overlap. At this time, the end 21a at one end of the second stent section 21 is positioned inside the end 11a at the other end of the first stent section 11. As a result, the first stent section 11 and the second stent section 21 are connected in the axial direction to form the stent 1 within a biological lumen.

[0014] The first stent section 11 and the second stent section 21 each have a main body section that forms the framework of the stent 1. Hereinafter, the main body section of the first stent section 11 will also be referred to as the first main body section 12, and the main body section of the second stent section 21 will also be referred to as the second main body section 22. In addition, when describing parts common to the first main body section 12 and the second main body section 22, they may be collectively referred to as the first and second main body sections 12, 22. A tubular coating (not shown) made of, for example, silicone resin, fluororesin, polyester resin, etc. may be attached to at least one of the inner and outer circumferential surfaces of the first and second main body portions 12, 22. In the following description, as an example of the stent 1, a bare stent configuration without a coating on the circumferential surfaces of the first and second main body portions 12, 22 will be shown.

[0015] The first and second main body portions 12, 22 are formed into a cylindrical shape having approximately the same overall diameter. In the first and second main body portions 12, 22, openings provided at both ends in the axial direction Ax communicate with each other, and a flow path is formed therein through which substances flowing through the digestive tract can pass when the stent 1 is placed in the digestive tract. In addition, materials that pass through the digestive tract include, for example, food immediately after ingestion that has not been digested at all, food that has been broken down as it passes through the digestive tract, and materials that have passed through the digestive tract but have not been digested (for example, feces), and the state of the material does not matter.

[0016] In addition, the first and second main body portions 12, 22 are expandable from a contracted state in which they contract radially inward to an expanded state in which they expand radially outward, and have a so-called self-expanding configuration in which the shape of the expanded state is memorized.

[0017] Here, the first stent section 11 and the second stent section 21 are housed in a sheath 31 of the placement device 30 described below and introduced into the digestive tract 3 in a state where they are contracted radially inward. After being delivered to the lesion site 3a of the digestive tract 3, the first stent section 11 and the second stent section 21 are released from the sheath 31 and expand radially outward. Note that the stent sections released from the placement device 30 may be expanded radially outward by inflating and pressing a balloon (not shown) from the inside.

[0018] The first and second main bodies 12, 22 are formed, for example, by weaving metal wires into a fence-like structure. Examples of materials for the wires of the first and second main bodies 12, 22 include known metals or metal alloys, such as Ni-Ti alloys, stainless steel, and titanium alloys. The first and second main bodies 12, 22 may also be formed from materials other than metals (such as ceramics or resins).

[0019] Furthermore, an alloy material having radiopaque properties may be used for the wire material of the first and second main body portions 12, 22, or a marker piece (not shown) made of an alloy material having radiopaque properties may be attached to the wire material as appropriate. In these cases, the positions of the first stent portion 11 and the second stent portion 21 can be confirmed from outside the body.

[0020] When a Ni-Ti alloy is used as the material for forming the first and second main body portions 12, 22, the first and second main body portions 12, 22 can be adjusted to their expanded shape and then subjected to a predetermined heat treatment, thereby allowing the expanded shape to be memorized in the first and second main body portions 12, 22.

[0021] The configuration of the first and second main body portions 12, 22 is not limited to the above. For example, the first and second main body portions 12, 22 may be formed by weaving metal wires in a lattice or spiral pattern using other weaving methods. Alternatively, the first and second main body portions 12, 22 may be formed by laser cutting a thin-walled cylinder made of any of the above metals, and forming the first and second main body portions 12, 22 in a pattern in which thin metal wires are wound spirally while being folded back in a zigzag pattern.

[0022] Furthermore, a first flared portion 13 whose diameter increases toward the one end is formed at one end of the first main body portion 12. Furthermore, a second flared portion 23 whose diameter increases toward the other end is formed at the other end of the second main body portion 22. The first flared portion 13 and the second flared portion 23 are both formed, for example, by braiding wire, and function to generate friction between the stent 1 and the inner wall of the digestive tract 3 when the stent 1 is placed, thereby suppressing displacement (migration) of the stent 1. Although the first and second flared portions 13, 23 have been exemplified as mechanisms for suppressing displacement (migration) of the stent 1, these are merely examples and are not limited thereto, and the stent may be composed of barbs (spikes, barbs) that pierce the inner wall of the digestive tract (biological lumen) 3, for example.

[0023] Furthermore, a restricting portion 2 for restricting relative axial displacement with respect to the opposing other stent portion is provided on at least one of the other end side of the first main body portion 12 and one end side of the second main body portion 22. In this embodiment, as an example of the restricting portion 2, as shown in Figures 1(a) and 4(a), a reduced diameter portion 14 is formed on the other end side of the first main body portion 12, and an expanded diameter portion 24 is formed on one end side of the second main body portion 22.

[0024] The reduced diameter section 14 has a tapered shape in which the diameter narrows toward the tip on the other end. The expanded diameter section 24 has a tapered shape in which the diameter widens toward the tip on one end. In Figures 1(a) and 4(a), for example, the inclination of the taper of the reduced diameter section 14 and the expanded diameter section 24 relative to a line extending in the axial direction Ax and the axial dimension are set to be approximately the same, but the inclination and axial dimension of the taper may be different.

[0025] 4(b) and 4(c) are diagrams showing examples of the positional relationship between the reduced diameter section 14 and the expanded diameter section 24 during stent placement. For simplicity, the elements of the first stent section 11 and the second stent section 21 are shown in line diagrams in FIGS. 4(b) and 4(c). FIG. 4(b) shows a case where the reduced diameter section 14 of the first stent section 11 and the expanded diameter section 24 of the second stent section 21 are positioned to overlap in the axial direction Ax. FIG. 4(c) shows a case where the expanded diameter section 24 of the second stent section 21 is positioned closer to one end than the reduced diameter section 14 of the first stent section 11 in the axial direction Ax.

[0026] 4(b), the overall length of the stent 1 in Fig. 4(c) is shorter due to the longer axial length of the overlapping region OA of the first stent section 11 and the second stent section 21. In other words, in this embodiment, the overall length of the stent 1 placed in the lesion site can be changed by adjusting the axial position of the second stent section 21 relative to the first stent section 11.

[0027] Furthermore, the stent 1 of this embodiment can maintain the entire length of the stent 1 placed in the lesion site by the restricting portion 2. Hereinafter, an explanation will be given with reference to Figures 4(b) and (c).

[0028] When the second stent section 21, which is in a contracted state in the position shown in Figure 4(b), expands, the expanded diameter section 24 of the second stent section 21 abuts against the inside of the reduced diameter section 14 of the first stent section 11, which has been expanded in advance. The reduced diameter section 14 of the first stent section 11 is then biased radially outward from the inside by the expansion force of the expanded diameter section 24. Meanwhile, because the first stent section 11 is supported by the inner wall of the digestive tract 3, a reaction force is exerted by the reduced diameter section 14 on the expanded diameter section 24 of the second stent section 21, pushing it radially inward. As a result, in Figure 4(b), the reduced diameter section 14 of the first stent section 11 and the expanded diameter section 24 of the second stent section 21 engage with each other, and axial displacement between the first stent section 11 and the second stent section 21 is mutually restricted, maintaining the overall length of the stent 1.

[0029] 4(c), the expanded diameter portion 24 of the second stent portion 21 faces the inner periphery of the first main body portion 12, and the reduced diameter portion 14 of the first stent portion 11 faces the outer periphery of the second main body portion 22. When the second stent portion 21 in a contracted state in this position expands, the first main body portion 12 supported by the inner wall of the digestive tract 3 is urged radially outward from the inside by the expansion force of the expanded diameter portion 24, while the expanded diameter portion 24 receives a reaction force from the first main body portion 12. The expanding second main body portion 22 is pressed down from the outside by the radially inward force of the reduced diameter portion 14. As a result, even in FIG. 4(c), the opposing second main body portion 22 is restrained at the position of the reduced diameter portion 14, and the opposing first main body portion 12 is restrained at the position of the expanded diameter portion 24. Therefore, axial displacement between the first stent portion 11 and the second stent portion 21 is restricted, and the overall length of the stent 1 is maintained.

[0030] 4(b) and 4(c), when the stent 1 of this embodiment is placed, an area OA is created where the first stent section 11 and the second stent section 21 overlap. In the area OA, the expansion forces of both the first stent section 11 and the second stent section 21 act, thereby enhancing the expansion force of the stent 1. In addition, in the region OA, the mesh of the skeleton is arranged with deviations in the axial and circumferential directions, so that the mesh of the skeleton is finer than in the region where the first stent section 11 and the second stent section 21 do not overlap.

[0031] In this embodiment, an example has been described in which a reduced diameter section 14 and an expanded diameter section 24 are provided as the regulating section 2 that regulates the axial displacement of the first stent section 11 and the second stent section 21, but it is also possible to provide either the reduced diameter section 14 or the expanded diameter section 24 and omit the other.

[0032] Alternatively, multiple types of products with different axial lengths may be prepared for either the first stent section 11 or the second stent section 21, and the length may be adjusted by changing the combination of stent sections to be placed in the biological lumen according to the lesion site. In this case, the length of the stent section is adjusted in advance according to the length of the lesion site, so that by engaging the reduced diameter section 14 and the expanded diameter section 24 and placing the stent section, a stent 1 with an appropriate overall length for the lesion site can be placed.

[0033] FIG. 5 is a diagram showing an example of an indwelling device 30 used when placing the first stent section 11 and the second stent section 21 in a lesion site. The placement device 30 includes a sheath 31 and an axial member 32 that is disposed inside the sheath 31 and is capable of locking the first stent section 11 and the second stent section 21 .

[0034] The sheath 31 is a long tubular member made of a flexible material such as a biocompatible synthetic resin, and is capable of housing the first stent section 11 and the second stent section 21 in a contracted state inside the sheath 31.

[0035] The shaft-shaped member 32 is an elongated member configured to be movable inside the sheath 31 along the axial direction Ax of the sheath 31. For example, the shaft-shaped member 32 has an outer shaft portion 32a and an inner shaft portion 32b inserted into the outer shaft portion 32a.

[0036] The outer shaft portion 32a is a long tubular member having a substantially constant outer diameter. A second locked portion 34 to which the second stent portion 21 is locked is provided on the distal end side of the outer shaft portion 32a. The inner shaft portion 32b is coaxially inserted into the outer shaft portion 32a so that their axes are substantially aligned, and one end portion thereof is exposed from the outer shaft portion 32a. A distal tip 35 that closes the opening on one end side of the sheath 31 is attached to one end of the inner shaft portion 32b. Furthermore, a first locked portion 33 to which the first stent portion 11 is locked is provided on the inner shaft portion 32b slightly toward the other end side of the distal tip 35.

[0037] In the placement device 30, when the sheath 31 is displaced toward the other end along the axial direction Ax while the position of the axial member 32 is fixed, the first stent section 11 engaged with the first engaged portion 33 of the inner shank 32b is released into the biological lumen from inside the sheath 31. At this time, the second stent section 21 engaged with the second engaged portion 34 of the outer shank 32a is restricted from moving in the axial direction Ax relative to the sheath 31, and the second stent section 21 moves integrally with the sheath 31 toward the other end in the axial direction Ax.

[0038] After the first stent section 11 is released, the second stent section 21 is released so as to overlap the first stent section 11 from the inside, while its position is confirmed using an endoscope or X-ray. Specifically, after the first stent section 11 is released, the restriction on the movement of the second stent section 21, which is engaged with the second engaged portion 34 of the outer shaft section 32a, in the axial direction Ax relative to the sheath 31 is released. Then, when the sheath 31 is displaced along the axial direction Ax toward the other end with the position of the axial member 32 fixed, the second stent section 21, which is engaged with the second engaged portion 34 of the outer shaft section 32a, is released from inside the sheath 31 into the biological lumen.

[0039] In addition, examples of means for switching between restricting and releasing the axial movement of the second stent portion 21 relative to the sheath 31 include a configuration in which the outer shaft portion 32a is pressed and clamped from the outer surface side by an operating portion (not shown) provided on the other end side of the placement device 30, and a configuration in which a predetermined portion of the outer shaft portion 32a is engaged with a predetermined portion of the operating portion.

[0040] In this manner, the first stent section 11 and the second stent section 21 can be placed at a desired position within a biological lumen using a single placement device 30. The configuration of the placement device 30 is not limited to the above. For example, a cylindrical member may be placed between the housing section for the first stent section 11 and the housing section for the second stent section 21 within the sheath 31 to form a partition, so that the second stent section 21 is not released when the first stent section 11 is released.

[0041] The effects of the stent 1 of this embodiment will be described below. The cylindrical stent 1 of this embodiment includes a first stent section 11 and a second stent section 21 that are expandable and contractable in a radial direction substantially perpendicular to the axial direction Ax. The first stent section 11 and the second stent section 21 are placed in a biological lumen (digestive tract 3) with their opposing axial end sections 11a, 21a overlapping each other. The first stent section 11 and the second stent section 21 also have restricting sections 2 (reduced diameter section 14, expanded diameter section 24) in an area OA where they overlap with each other that restricts their relative axial displacement with respect to the other stent section. According to this embodiment, the overall length of the stent 1 placed at the lesion site can be changed by adjusting the overlapping width of the stent sections or by changing the combination of the stent sections. Furthermore, since the restricting section 2 restricts the relative axial displacement between the first stent section 11 and the second stent section 21, the overall length of the stent 1 made up of multiple stent sections is maintained. Therefore, the stent 1 of this embodiment can be placed with an axial length appropriate for the axial length of the lesion site. In other words, in this embodiment, the portion of the stent 1 placed in healthy areas beyond the lesion site can be reduced, thereby reducing the possibility of damage to healthy areas.

[0042] In the stent 1 of this embodiment, the expansion forces of both the first stent section 11 and the second stent section 21 act in the overlapping region OA of the first stent section 11 and the second stent section 21, thereby enhancing the expansion force of the stent 1, thereby making it possible to expand the lesion site more reliably. Furthermore, in the overlapping region OA of the first stent section 11 and the second stent section 21, the mesh of the skeleton is shifted and becomes finer, making it easier to suppress the phenomenon of cell tissue from the lesion site infiltrating into the stent 1 (ingrowth).

[0043] Furthermore, the restricting section 2 of this embodiment has an engagement structure that allows the opposing ends in the axial direction Ax to engage with each other by the reduced-diameter section 14 of the first stent section 11 and the expanded-diameter section 24 of the second stent section 21. By engaging the first stent section 11 and the second stent section 21, it becomes easier to more reliably restrict relative axial displacement between the placed first stent section 11 and second stent section 21.

[0044] The present invention is not limited to the above-described embodiment, and various improvements and design changes may be made without departing from the spirit of the present invention.

[0045] The configuration of the restricting portion 2 of the present invention is not limited to the shapes of the reduced diameter portion 14 and the expanded diameter portion 24 exemplified in the above embodiment, but can be modified arbitrarily as appropriate. As an example, as shown in Fig. 6, the second stent section 21 may have a plurality of tapered, enlarged-diameter sections 24 formed in the same direction in the axial direction Ax. According to the configuration of Fig. 6, the overall length of the stent 1 can be adjusted by engaging any of the plurality of enlarged-diameter sections 24 with the reduced-diameter section 14 of the first stent section 11. Furthermore, according to the configuration of Fig. 6, the reduced-diameter section 14 and the enlarged-diameter section 24 can be engaged at a plurality of positions in the axial direction Ax, making it easier to reliably restrict axial displacement between the deployed stent sections. Although not shown in the drawings, instead of forming a plurality of enlarged-diameter sections 24 in the second stent section 21, the first stent section 11 may have a plurality of tapered, enlarged-diameter sections 14 formed in the same direction in the axial direction Ax.

[0046] FIG. 7 is a diagram showing another example of the configuration of the restriction portion 2. In the example of FIG. 7, annular slits 15, 25, in which no wire is woven, are provided as restriction portion 2 in parts of first and second main body portions 12, 22, respectively. As shown in FIG. 7(a), at the locations of slits 15, 25, unwoven wire is arranged so as to protrude in a zigzag pattern along the circumferential direction. When second stent portion 21 is expanded inside first stent portion 11, as shown in FIG. 7(b), the wire protruding in a zigzag pattern at slits 15, 25 gets caught on the framework of the other stent portion, thereby engaging first stent portion 11 and second stent portion 21. This allows for the restriction of axial displacement between the deployed stent portions. The axial lengths of the slits 15, 25 and the lengths of the portions of the first and second body portions 12, 22 distal to the slits 15, 25 are merely examples and are not intended to be limiting and can be changed as appropriate. For example, the portion of the second body portion 22 distal to the slit 25 may be hooked onto the slit 15, or the portion of the first body portion 12 distal to the slit 15 may be hooked onto the slit 25.

[0047] Furthermore, although not shown, a plurality of slits 15 may be provided in the axial direction in the first stent section 11, and a plurality of slits 25 may be provided in the axial direction in the second stent section 21. This allows the first stent section 11 and the second stent section 21 to be engaged at a plurality of positions in the axial direction using the plurality of slits 15 or the plurality of slits 25, and more reliably restricts axial displacement of the placed stent sections 11, 21 relative to each other.

[0048] As another example of the configuration of the restricting section 2 of the present invention, for example, a locking pin (such as a barb) for hooking onto the framework of the other stent section may be provided on at least one of the inner circumferential side of the first stent section 11 and the outer circumferential side of the second stent section 21. In this case, the locking pin hooks onto the framework of the other stent section, thereby engaging the first stent section 11 and the second stent section 12, and it is possible to restrict axial displacement of the placed stent sections relative to each other.

[0049] As another example of the configuration of the restricting portion 2 of the present invention, when the stent 1 has a coating portion, the two coating portions may be bonded together to restrict the axial displacement of the stent portions. For example, the coating portion may be formed using a biocompatible soluble material, and the coating portions may be bonded together by dissolving the coating. In the above, the coating material may be one that begins to dissolve at about body temperature, or one that begins to dissolve upon contact with water or components of bodily fluids such as blood. Alternatively, a biocompatible adhesive layer made of a medical adhesive or the like may be formed on the surface of the coating portion to bond the coating portions together.

[0050] Furthermore, the embodiments disclosed herein should be considered to be illustrative and not restrictive in all respects. The scope of the present invention is defined by the claims, not by the above description, and is intended to include all modifications within the meaning and scope of the claims. [Explanation of symbols]

[0051] 1... stent, 2... restriction portion, 3... digestive tract, 3a... lesion site, 11... first stent portion, 12... first main body portion, 14... reduced diameter portion, 21... second stent portion, 22... second main body portion, 24... expanded diameter portion, 30... placement device, 31... sheath

Claims

1. A cylindrical stent to be placed in a biological lumen, a plurality of stent sections that are expandable and contractable in a radial direction substantially perpendicular to the axial direction; the plurality of stent sections are placed in the biological lumen with opposing axial end portions overlapping each other, At least one of the plurality of stent sections has a restriction section in an area overlapping with the other stent section, which restricts relative displacement in the axial direction with respect to the other stent section, The end of the one stent section into which the end of the other stent section is inserted is inclined so that the outer diameter decreases toward the tip side in the axial direction. Stent.

2. A cylindrical stent to be placed in a biological lumen, a plurality of stent sections that are expandable and contractable in a radial direction substantially perpendicular to the axial direction; the plurality of stent sections are placed in the biological lumen with opposing axial end portions overlapping each other, At least one of the plurality of stent sections has a restriction section in an area overlapping with the other stent section, which restricts relative displacement in the axial direction with respect to the other stent section, The end of the other stent section that is inserted into the end of the one stent section is inclined so that the outer diameter increases toward the tip side in the axial direction. Stent.

3. The restricting portion has an engaging structure that allows opposing axial ends of the plurality of stent portions to engage with each other.

3. A stent according to claim 1 or 2.

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