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WO2018211796A1 - Stent - Google Patents

Stent Download PDF

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Publication number
WO2018211796A1
WO2018211796A1 PCT/JP2018/009100 JP2018009100W WO2018211796A1 WO 2018211796 A1 WO2018211796 A1 WO 2018211796A1 JP 2018009100 W JP2018009100 W JP 2018009100W WO 2018211796 A1 WO2018211796 A1 WO 2018211796A1
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WO
WIPO (PCT)
Prior art keywords
stent
portions
strut
dense
axis
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/JP2018/009100
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English (en)
Japanese (ja)
Inventor
翔平 海田
亮輔 上田
有真 河本
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Terumo Corp
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Terumo Corp
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Filing date
Publication date
Application filed by Terumo Corp filed Critical Terumo Corp
Publication of WO2018211796A1 publication Critical patent/WO2018211796A1/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

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    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61F—FILTERS IMPLANTABLE INTO BLOOD VESSELS; PROSTHESES; DEVICES PROVIDING PATENCY TO, OR PREVENTING COLLAPSING OF, TUBULAR STRUCTURES OF THE BODY, e.g. STENTS; ORTHOPAEDIC, NURSING OR CONTRACEPTIVE DEVICES; FOMENTATION; TREATMENT OR PROTECTION OF EYES OR EARS; BANDAGES, DRESSINGS OR ABSORBENT PADS; FIRST-AID KITS
    • A61F2/00—Filters implantable into blood vessels; Prostheses, i.e. artificial substitutes or replacements for parts of the body; Appliances for connecting them with the body; Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents
    • A61F2/82—Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents
    • A61F2/86—Stents in a form characterised by the wire-like elements; Stents in the form characterised by a net-like or mesh-like structure
    • A61F2/90—Stents in a form characterised by the wire-like elements; Stents in the form characterised by a net-like or mesh-like structure characterised by a net-like or mesh-like structure
    • A61F2/91—Stents in a form characterised by the wire-like elements; Stents in the form characterised by a net-like or mesh-like structure characterised by a net-like or mesh-like structure made from perforated sheets or tubes, e.g. perforated by laser cuts or etched holes
    • A61F2/915—Stents in a form characterised by the wire-like elements; Stents in the form characterised by a net-like or mesh-like structure characterised by a net-like or mesh-like structure made from perforated sheets or tubes, e.g. perforated by laser cuts or etched holes with bands having a meander structure, adjacent bands being connected to each other

Definitions

  • the present invention relates to a stent used for improving a stenosis or occlusion occurring in a body lumen such as a blood vessel, a bile duct, a trachea, an esophagus, or a urethra.
  • Patent Document 1 discloses a stent delivery system including a stent having a dense portion occupied by a wire member having a large occupation density and a sparse portion occupied by a wire member having a small occupation density.
  • Stents are used to treat various diseases caused by stenosis or occlusion of blood vessels or other biological lumens, to expand the stenosis or occlusion, and to ensure the patency of the biological lumen. Or it is a medical device detained in an obstruction
  • the stent is attached in a contracted state to, for example, a stent delivery system disclosed in Patent Document 1 and the like, inserted from outside the living body into the living body, and delivered to the target site.
  • the stent When the stent passes through the living body lumen and is delivered to the target site, the stent is required to be able to pass through the living body lumen flexibly following the bending of the living body lumen. . For example, a higher passability is required for a stent that expands a stenosis or occlusion in a coronary artery.
  • One of the physical properties that contributes to the passage of the stent is the bending rigidity of the stent. That is, if the bending rigidity of the stent is relatively low, the passage of the stent is relatively high. Bending stiffness is proportional to the cross-sectional second moment when the material is a single material and represents resistance to bending deformation.
  • a measure for reducing the bending rigidity of the stent there is a method of reducing the amount of the constituent material of the stent.
  • the stent is required to have strength (radial force: radial force) for maintaining the state in which the stenosis portion is pushed and expanded.
  • radial force radial force
  • the amount of the constituent material of the stent is reduced, the bending rigidity of the stent is lowered, while the radial force required for the stent may not be maintained.
  • the present invention has been made to solve the above-described problems, and an object of the present invention is to provide a stent capable of improving the passage through a living body lumen while maintaining a radial force.
  • the subject is a stent that is placed in a living body lumen, and includes a plurality of orbiting portions having linear struts that are formed around a shaft and formed in a cylindrical shape,
  • the plurality of circulation parts are arranged side by side along the axial direction, and each of the plurality of circulation parts is provided with a plurality of first portions provided at positions facing each other with respect to the axis in the circumferential direction;
  • a plurality of second portions provided at positions facing each other in the circumferential direction and having a rigidity smaller than the rigidity of the struts of the first portion in a state where at least a part of the plurality of rotating portions is bent.
  • the plurality of circular portions provided in the stent are arranged side by side along the axis of the stent.
  • Each circulating portion has a plurality of first portions and a plurality of second portions.
  • the plurality of first portions are provided at positions facing each other with respect to the axis of the stent in the circumferential direction.
  • the plurality of second portions are provided at positions facing each other with respect to the stent axis in the circumferential direction, and have a rigidity smaller than the rigidity of the struts of the first portion in a state where at least a part of the plurality of circulation portions is bent. .
  • the rigidity of the struts of the second part is smaller than the rigidity of the struts of the first part in a state where at least a part of the plurality of circulation parts is bent.
  • the plurality of first portions are continuously arranged along the axial direction of the stent over the plurality of rotating portions in a state in which the positional relationship facing each other with respect to the axis of the stent is maintained in the circumferential direction. Therefore, the bending stiffness when the stent bends in a posture in which the first part is arranged at the position of the neutral surface is smaller than the bending stiffness when the stent bends in another posture.
  • the stent is easily bent in a posture in which the first part is disposed at the position of the neutral surface. That is, directivity can be given to the bending rigidity of the stent. Therefore, the stent can pass through the bent portion of the living body lumen in a posture in which the bending rigidity is minimized more reliably. Thereby, the passage of the stent in the living body lumen can be improved.
  • the stent can be easily bent. Thereby, the amount of struts in the entire stent can be secured, and the radial force required for the stent can be maintained.
  • the circumferential portion is a corrugated body in which the strut is bent, and a distal-end bending portion having a vertex on the distal end side in the axial direction and a proximal-side bending having a vertex on the proximal end side in the axial direction. And a wavy body having a portion.
  • the orbiting portion is a wavy body in which the strut is bent.
  • the corrugated body has a distal-end bending portion having a vertex on the distal end side in the axial direction of the stent and a proximal-end bending portion having a vertex on the proximal end side in the axial direction of the stent. Accordingly, the stent can follow the bending of the living body lumen more flexibly and pass through the living body lumen. That is, the passage of the stent in the living body lumen can be further improved.
  • the plurality of first portions are arranged on a straight line along the axial direction over the plurality of circulation portions in a state in which a positional relationship facing each other with respect to the axis is maintained in the circumferential direction. It is characterized by.
  • the neutral surface when the stent is bent is formed on a straight line along the axial direction of the stent. Therefore, the stent is easy to bend in a certain direction in a posture in which the first portion is disposed at the position of the neutral surface formed linearly over the entire length of the stent. Thereby, the directivity of the bending rigidity of the stent is improved, and the passing property of the stent in the living body lumen is further improved.
  • the plurality of first portions are arranged in a spiral shape along the axial direction over the plurality of circulation portions in a state in which a positional relationship facing each other with respect to the axis is maintained in the circumferential direction. It is characterized by.
  • the neutral surface when the stent is bent is formed in a spiral shape along the axial direction of the stent. Therefore, the stent can be easily bent in a posture in which the first portion is disposed at the position of the neutral surface formed in a spiral shape, and the directivity can be improved. In other words, the neutral surface of the stent changes along each of the plurality of rotating portions along the axial direction.
  • the stent when the stent passes through a meandering blood vessel site, the stent can pass through the blood vessel site while taking a posture in which the bending rigidity is locally minimized. Thereby, the passage of the stent in the living body lumen is further improved.
  • the plurality of first portions includes a first dense portion in which a proportion of the volume of the struts in a unit volume of the space including the struts is higher than the proportion in the second portions;
  • a second dense portion provided at a position facing the first dense portion and the axis in the circumferential direction, wherein the proportion is higher than the proportion of the second portion. It is characterized by that.
  • the plurality of first portions have the first dense portion and the second dense portion.
  • the proportion (volume density) of the strut volume in the unit volume of the space including the struts in the first dense portion is higher than the strut volume density in the second region.
  • the volume density of the struts in the second dense portion is higher than the volume density of the struts in the second region.
  • the first dense portion and the second dense portion are provided at positions facing each other with respect to the stent axis in the circumferential direction. Therefore, the bending rigidity when the stent bends in a posture in which the first dense portion and the second dense portion are arranged at the position of the neutral surface is smaller than the bending stiffness when the stent bends in another posture. Therefore, the stent is easily bent in a posture in which the first dense portion and the second dense portion are arranged at the position of the neutral surface. That is, directivity can be given to the bending rigidity of the stent. Therefore, the stent can pass through the bent portion of the living body lumen in a posture in which the bending rigidity is minimized.
  • the passage of the stent in the living body lumen can be improved.
  • the first dense portion and the second dense portion are arranged at the position of the neutral surface that has little influence on the bending rigidity of the stent. That is, in the bending deformation of the stent, the first dense portion and the second dense portion, in which the amount of struts forming the circumference of the stent is larger than the amount of struts in the second portion, have little influence on the bending rigidity of the stent.
  • Arranged at the position of the elevation Thereby, the amount of struts in the entire stent can be secured, and the radial force required for the stent can be maintained.
  • the circumferential interval between the struts in each of the first dense portion and the second dense portion is narrower than the circumferential interval between the struts in the second portion.
  • part are formed because the space
  • the first dense portion and the second dense portion can be formed relatively easily, and the passage of the stent in the living body lumen can be improved while maintaining the radial force of the stent.
  • the axial length of the strut in each of the first dense portion and the second dense portion is longer than the axial length of the strut in the second portion.
  • the length (amplitude) of the strut in the axial direction of the stent changes, so that the first dense portion and the second dense portion in which the volume density of the strut is higher than the volume density of the strut in the second portion. Is formed.
  • the first dense portion and the second dense portion can be formed relatively easily, and the passage of the stent in the living body lumen can be improved while maintaining the radial force of the stent.
  • a line width of the strut in each of the first dense portion and the second dense portion is larger than a line width of the strut in the second portion.
  • the first dense portion and the second dense portion in which the volume density of the strut is higher than the volume density of the strut in the second portion are formed by changing the line width of the strut.
  • the thickness of the strut in each of the first dense portion and the second dense portion is larger than the thickness of the strut in the second portion.
  • the first dense portion and the second dense portion in which the volume density of the strut is higher than the volume density of the strut in the second portion are formed by changing the thickness (the length in the radial direction) of the strut.
  • the first dense portion and the second dense portion are formed by the change in the thickness of the strut, and the passage of the stent in the living body lumen can be improved while maintaining the radial force of the stent.
  • the material property of the strut in the first part is different from the material property of the strut in the second part.
  • the material properties of the struts of the first part are different from the material properties of the struts of the second part.
  • the rigidity of the struts of the second part is different from the rigidity of the struts of the first part. Accordingly, the first portion and the second portion are formed by the difference in the material characteristics of the strut, and the passage of the stent in the living body lumen can be improved while maintaining the radial force of the stent.
  • the surrounding portion is an annular body in which the struts extend in an annular shape, and at least one of the plurality of first portions is a connecting portion that connects the surrounding portions adjacent to each other in the axial direction. It is characterized by having.
  • the circulating portion is an annular body in which struts extend in an annular shape.
  • At least one of the plurality of first portions has a connecting portion that connects the circumferential portions adjacent to each other in the axial direction of the stent. Therefore, the 1st site
  • part are formed by arrange
  • the circulating portion is a spiral body in which the struts extend spirally.
  • the circulating portion is a spiral body in which the struts extend spirally. Therefore, even if the connection part which connects the mutually adjacent surrounding parts is not provided, the surrounding parts are continuing spirally. And a some 1st site
  • a stent that can improve the passage through a living body lumen while maintaining a radial force.
  • the stent according to the embodiment of the present invention is used to treat a stenosis (treatment site) generated in a blood vessel that is a living body lumen.
  • the stent is configured as an indwelling member that is expanded and placed in a blood vessel and pushes the stenosis part by supporting the inside of the stenosis part.
  • the stent is not limited to the application to blood vessels, but is applied to the treatment of various biological lumens (for example, bile duct, trachea, esophagus, urethra, nasal cavity, other organs, etc.).
  • the side to be inserted into the lumen left side in FIGS.
  • FIG. 1 to 4, 6 to 8, and 10 to 12 is the “tip” or “tip side”, and the proximal side (FIG. 1 to FIG. 4, FIG. 6 to FIG. 8, and FIG. 10 to FIG. 12 are referred to as “base end” or “base end side”.
  • FIG. 1 is a front view showing a stent delivery system for delivering a stent according to an embodiment of the present invention.
  • FIG. 2 is a partial cross-sectional view of the distal end portion of the stent delivery system shown in FIG.
  • FIG. 3 is a partial cross-sectional view for explaining the operation of the stent delivery system shown in FIG.
  • the stent delivery system 2 shown in FIG. 1 includes a balloon catheter 3 having a balloon 32 and a stent 4 attached to the balloon 32.
  • the balloon catheter 3 has a tube-shaped shaft main body 31 and a foldable and expandable balloon 32 provided at the distal end of the shaft main body 31. That is, the balloon 32 is provided at the distal end portion of the shaft main body 31 so that it can be expanded and contracted.
  • the stent 4 is attached to the balloon 32 so as to encapsulate the deflated balloon 32, and is expanded by the expansion of the balloon 32.
  • the stent 4 is a so-called balloon-expandable stent that has a diameter for insertion into a lumen in a living body and is expandable when a force spreading in the radial direction from the inside of the tubular body is applied.
  • the stent 4 according to the present embodiment is not necessarily limited to a balloon expandable stent, and may be a self-expandable stent that automatically shifts from a contracted state to an expanded state by elastic recovery. In the following description, a case where the stent 4 is a balloon expandable stent will be described as an example.
  • the shaft main body 31 has a guide wire lumen 314.
  • One end of the guide wire lumen 314 is open at the tip of the shaft body 31.
  • the other end of the guide wire lumen 314 is open at the base end of the shaft body 31.
  • the shaft main body 31 includes an inner tube 311, an outer tube 312, and a branch hub 313.
  • the inner tube 311 is a tube body having a guide wire lumen 314 for inserting a guide wire therein.
  • the length of the inner tube 311 is 100 to 2500 mm, more preferably 250 to 2000 mm.
  • the outer diameter of the inner tube 311 is 0.1 to 1.0 mm, more preferably 0.3 to 0.7 mm.
  • the wall thickness of the inner tube 311 is 10 to 250 ⁇ m, more preferably 20 to 100 ⁇ m.
  • the inner tube 311 is inserted into the outer tube 312. The distal end portion of the inner tube 311 protrudes more distally than the outer tube 312.
  • a balloon expansion lumen 315 is formed between the outer surface of the inner tube 311 and the inner surface of the outer tube 312 and has a sufficient volume.
  • the outer tube 312 is a tube body in which the inner tube 311 is inserted.
  • the distal end of the outer tube 312 is located at a portion slightly retracted from the distal end of the inner tube 311.
  • the length of the outer tube 312 is 100 to 2500 mm, more preferably 250 to 2000 mm.
  • the outer diameter of the outer tube 312 is 0.5 to 1.5 mm, more preferably 0.7 to 1.1 mm.
  • the wall thickness of the outer tube 312 is 25 to 200 ⁇ m, more preferably 50 to 100 ⁇ m.
  • the outer tube 312 includes a distal end side outer tube 312a and a proximal end side outer tube 312b.
  • the distal end side outer tube 312a and the proximal end side outer tube 312b are joined to each other.
  • the distal end side outer tube 312a is tapered in the vicinity of the joint between the distal end side outer tube 312a and the proximal end side outer tube 312b. Therefore, the diameter of the distal outer tube 312a on the distal end side with respect to the tapered portion is smaller than the diameter of the proximal outer tube 312b on the proximal end side with respect to the tapered portion.
  • the outer diameter of the small-diameter portion (the portion closer to the tip side than the taper portion) of the tip-side outer tube 312a is 0.5 to 1.5 mm, preferably 0.6 to 1.1 mm. Further, the outer diameter of the proximal end portion of the distal end side outer tube 312a (the portion closer to the proximal end than the tapered portion) and the proximal end side outer tube 312b is 0.75 to 1.5 mm, preferably 0.9 to 1.. 1 mm.
  • the outer tube 312 does not necessarily have to have the distal end side outer tube 312a and the proximal end side outer tube 312b. That is, the outer tube 312 may be formed as a tube body having substantially the same diameter over the entire length.
  • the material for forming the inner tube 311 and the outer tube 312 is preferably a material having a certain degree of flexibility.
  • polyolefin for example, polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, etc.
  • Polyvinyl chloride polyamide, polyamide elastomer, polyester, polyester elastomer, polyurethane and other thermoplastic resins, silicone rubber, latex rubber and the like.
  • the material for forming the inner tube 311 and the outer tube 312 is preferably the above-described thermoplastic resin, and more preferably polyamide or polyamide elastomer.
  • the balloon 32 is foldable, and is folded on the outer periphery of the inner tube 311 when not expanded.
  • the balloon 32 has an expandable portion that exhibits a cylindrical portion (preferably, a cylindrical portion) having substantially the same diameter so that the attached stent 4 can be expanded.
  • the substantially cylindrical portion may not be a complete cylinder but may be a polygonal column.
  • the balloon 32 has a distal end side joint portion 32a and a proximal end side joint portion 32b.
  • the distal end side joint portion 32 a is fixed at a position slightly proximal to the distal end of the inner tube 311. Specifically, the distal end side joint portion 32a is fixed to the inner tube 311 in a liquid-tight manner by an adhesive or heat fusion.
  • the proximal end joint portion 32 b is fixed to the distal end of the outer tube 312. Specifically, the proximal end side joining portion 32b is liquid-tightly fixed to the distal end of the outer tube 312 with an adhesive or heat fusion.
  • the balloon 32 is liquid-tightly fixed to the inner tube 311 and the outer tube 312 by an adhesive or heat fusion.
  • the balloon 32 communicates with the balloon expansion lumen 315 in the vicinity of the proximal end portion.
  • interval between the expandable part and the front end side junction part 32a and the base end side junction part 32b is formed in the taper shape.
  • the balloon 32 has an expansion space 32c formed between the inner surface of the balloon 32 and the outer surface of the inner tube 311.
  • the base end portion of the expansion space 32c communicates with the balloon expansion lumen 315 on the entire circumference.
  • the proximal end of the balloon 32 communicates with the balloon expansion lumen 315 having a relatively large volume. Therefore, the expansion fluid can be reliably injected from the balloon expansion lumen 315 into the balloon 32.
  • the expansion fluid may be a gas or a liquid. Examples of the expansion fluid include gases such as helium gas, CO 2 gas, and O 2 gas, and liquids such as physiological saline and contrast medium.
  • a material for forming the balloon 32 As a material for forming the balloon 32, a material having a certain degree of flexibility is preferable.
  • polyolefin for example, polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, cross-linked ethylene-vinyl acetate). Copolymer), polyvinyl chloride, polyamide, polyamide elastomer, polyurethane, polyester (for example, polyethylene terephthalate), polyester elastomer, polyarylene sulfide (for example, polyphenylene sulfide), thermoplastic resin, silicone rubber, latex rubber, etc.
  • the forming material of the balloon 32 is preferably a stretchable material.
  • the forming material of the balloon 32 is a biaxially stretched material having high strength and expansion force.
  • the outer diameter of the cylindrical portion (expandable portion) of the balloon 32 when the balloon 32 is expanded is 2 to 6 mm, preferably 2.5 to 5.5 mm.
  • the length of the balloon 32 is 5 to 50 mm, preferably 10 to 40 mm.
  • the outer diameter of the distal end side joint portion 32a is 0.9 to 1.5 mm, preferably 1 to 1.3 mm.
  • the length of the distal end side joint portion 32a is 1 to 5 mm, preferably 1 to 3 mm.
  • the outer diameter of the base end side joint portion 32b is 1 to 1.6 mm, preferably 1.1 to 1.5 mm.
  • the length of the base end side joining portion 32b is 1 to 5 mm, preferably 2 to 4 mm.
  • the stent delivery system 2 has two X-ray contrast members 316 and 317.
  • the X-ray contrast members 316 and 317 are fixed to the outer surface of the inner tube 311 at positions corresponding to both ends of the cylindrical portion (expandable portion) when the balloon 32 is expanded.
  • the two X-ray contrast members may be fixed at positions on the outer surface of the inner tube 311 at both ends of a predetermined length in the central portion of the stent 4.
  • a single X-ray contrast member may be fixed to a position that is the central portion of the stent 4 in the outer surface of the shaft main body 31.
  • a ring-shaped member having a predetermined length or a member obtained by winding a linear member in a coil shape is suitable.
  • a material for forming the X-ray contrast members 316 and 317 for example, gold, platinum, tungsten, iridium or an alloy thereof, or a silver-palladium alloy is preferable.
  • a branch hub 313 is fixed to the proximal end of the stent delivery system 2.
  • the branch hub 313 has an inner tube hub and an outer tube hub.
  • the inner tube hub is fixed to the inner tube 311 and has a guide wire port 313 a communicating with the guide wire lumen 314.
  • the outer tube hub is fixed to the outer tube 312 and has an injection port 313 b that communicates with the balloon expansion lumen 315.
  • the outer tube hub and the inner tube hub are fixed to each other.
  • the outer tube hub and the inner tube hub are fixed by inserting and joining the distal end of the inner tube 311 from the proximal end of the outer tube hub attached to the proximal end portion of the outer tube 312.
  • the inner tube hub and the outer tube hub can be securely fixed by applying and bonding an adhesive to the joint portion between the inner tube hub and the outer tube hub.
  • the material for forming the branch hub 313 examples include thermoplastic resins such as polycarbonate, polyamide, polysulfone, polyarylate, and methacrylate-butylene-styrene copolymer.
  • thermoplastic resins such as polycarbonate, polyamide, polysulfone, polyarylate, and methacrylate-butylene-styrene copolymer.
  • the structure of the proximal end of the stent delivery system 2 is not limited to the above structure.
  • a tube having a port member that forms an opening at the proximal end is attached to each of the guide wire lumen 314 and the balloon expansion lumen 315 in a liquid-tight manner.
  • a guide wire insertion port that communicates with the guide wire lumen may be provided in an intermediate portion of the stent delivery system.
  • the structure of the guide wire lumen 314 is not limited to the over-the-wire structure in which the proximal-side guide wire port 313a exists outside the patient's body, and the proximal-side guide wire port 313a is not the patient.
  • a rapid exchange structure existing in the body may be adopted.
  • the stent 4 is attached to the balloon 32 so as to encapsulate the balloon 32.
  • the stent 4 is manufactured by processing, for example, a tube or a pipe having an inner diameter smaller than that of the expanded stent 4 and an inner diameter larger than the outer diameter of the folded balloon 32. Then, the balloon 32 is inserted into the manufactured stent 4, and a uniform force is applied to the outer surface of the stent 4 inward to reduce the diameter, thereby forming the product-state stent 4. That is, the stent 4 is completed by compression mounting on the balloon 32.
  • the material for forming the stent 4 synthetic resin or metal is used.
  • the synthetic resin include synthetic resins having a certain degree of hardness and elasticity, and biocompatible synthetic resins are preferable.
  • the synthetic resin is a polyolefin (eg, polyethylene, polypropylene), polyester (eg, polyethylene terephthalate), fluororesin (eg, PTFE, ETFE), or polylactic acid, polyglycolic acid that is a bioabsorbable material, Or a copolymer of polylactic acid and polyglycolic acid.
  • the metal used as the material for forming the stent 4 is preferably a metal having biocompatibility, for example, a cobalt base alloy such as stainless steel, tantalum or tantalum alloy, platinum or platinum alloy, gold or gold alloy, or cobalt chromium alloy. And nickel titanium alloy. Moreover, after producing the shape of the stent 4, noble metal plating (gold, platinum) may be applied.
  • FIG. 4 is a developed view showing the stent according to the present embodiment.
  • FIG. 5 is a cross-sectional view illustrating a contracted state of the stent according to the present embodiment.
  • FIG. 6 is a front view illustrating the stent according to the present embodiment.
  • FIG. 5 is a cross-sectional view of the stent taken along section plane C1-C1 shown in FIG.
  • the stent 4 includes a plurality of rotating portions 41 arranged side by side along the direction of the axis X1 (see FIGS. 2 and 3).
  • the circulating portion 41 has a linear strut 411 as a strand, and is formed into a cylindrical skeleton as a whole by the strut 411.
  • the orbiting portion 41 has a linear strut 411 formed around the axis X ⁇ b> 1 of the stent 4 and formed in a cylindrical shape.
  • the circumferential portion 41 is formed as a wave-like body in which the strut 411 extends in the circumferential direction of the stent 4 and has a plurality of bent portions, and has a distal end side bent portion 412, a proximal end side bent portion 413, and a linear portion 414. .
  • the orbiting portion 41 is formed as an annular body in which the struts 411 extend in an annular shape.
  • the distal end side bent portion 412 has a vertex on the distal end side in the axial direction of the stent 4.
  • the proximal side bent portion 413 has a vertex on the proximal side in the axial direction of the stent 4.
  • the linear portion 414 is a linear portion that connects the distal end side bent portion 412 and the proximal end side bent portion 413.
  • the distal end side bent portion 412 and the proximal end side bent portion 413 correspond to the “bent portion” of the present invention, and are deformed when the stent 4 is expanded.
  • at least one of the distal end side bent portion 412 and the proximal end side bent portion 413 may be simply referred to as a “bent portion”.
  • the length of one rotating portion 41 is preferably about 0.7 to 2.0 mm.
  • the number of each of the distal end side bent portion 412 and the proximal end side bent portion 413 of one circumference portion is preferably 6 to 20, and particularly preferably 8 to 12.
  • the number of the circulating portions 41 is preferably 4-20. However, the number of each of the distal end side bent portion 412 and the proximal end side bent portion 413 and the number of the surrounding portions 41 are not limited to this.
  • the orbiting portion 41 of the stent 4 has a plurality of first portions 45 and a plurality of second portions 46.
  • the plurality of first portions 45 are provided at positions facing each other with respect to the axis X1 of the stent 4 in the circumferential direction.
  • the plurality of second portions are provided at positions facing each other with respect to the axis X1 of the stent 4 in the circumferential direction.
  • the rigidity of the struts 411 in the second part 46 is smaller than the rigidity of the struts 411 in the first part 45 in a state in which at least a part of the plurality of circulation parts is bent as indicated by an arrow A1 shown in FIG.
  • the “second portion” is a portion having a rigidity smaller than the rigidity of the strut of the first portion in a state where at least some of the plurality of surrounding portions are bent. And other than the first part.
  • the plurality of first portions 45 are arranged over the plurality of circumferential portions 41 in a state in which the first portions 45 maintain the positional relationship facing each other with respect to the axis X1 of the stent 4 in the circumferential direction. It arrange
  • the plurality of first portions 45 include a first dense portion 42 and a second dense portion 43.
  • the first dense portion 42 has a proportion (volume density) occupied by the volume of the strut 411 in the unit volume (compartment frame) V ⁇ b> 1 of the space including the strut 411 in comparison with the volume density of the strut 411 in the second portion 46.
  • the second dense portion 43 is a portion in which the proportion (volume density) of the volume of the strut 411 in the unit volume V1 of the space including the strut 411 is higher than the volume density of the strut 411 in the second portion.
  • the unit volume (compartment frame) V ⁇ b> 1 preferably includes a distal end side bent portion 412 of the strut 411 and a proximal end side bent portion 413 of the strut 411.
  • the second dense portion 43 is provided at a position facing the first dense portion 42 and the axis X ⁇ b> 1 of the stent 4 in the circumferential direction. 4 and 5, the first dense portion 42 is provided at a position of 90 degrees when the lower end portion of the circumferential portion 41 is set to 0 degree and is rotated counterclockwise. 43 is provided at a position of 270 degrees.
  • the positions of the first dense portion 42 and the second dense portion 43 are not limited to the examples shown in FIGS. 4 and 5, and the first dense portion 42 and the second dense portion 43 are arranged in the circumferential direction of the stent 4. There is no particular limitation as long as they are provided at positions facing each other with respect to the axis X1.
  • the circumferential interval (pitch) D1 between the struts 411 in the first dense portion 42 is narrower than the circumferential interval D3 between the struts 411 in the second portion 46.
  • the volume density of the struts 411 in the first dense portion 42 is higher than the volume density of the struts 411 in the second portion 46.
  • the circumferential interval D2 between the struts 411 in the second dense portion 43 is narrower than the circumferential interval D3 between the struts 411 in the second portion 46.
  • the volume density of the struts 411 in the second dense portion 43 is higher than the volume density of the struts 411 in the second portion 46.
  • the circumferential interval between the struts 411 in the vicinity of the lower end portion (around 0 degrees) of the rotating portion 41 is taken as an example as the circumferential interval D3 between the struts 411 in the second portion 46.
  • the second portion 46 is not limited to the vicinity of the lower end portion of the rotating portion 41, and refers to a portion other than the first portion 45 in the rotating portion 41 of the stent 4. Therefore, the circumferential interval between the struts 411 in the second portion 46 is not limited to the interval D3 illustrated in FIG.
  • the circumferential distance D3 between the struts 411 in the second portion 46 is larger than the circumferential distances D1 and D2 between the struts 411 in the first dense portion 42 and the second dense portion 43, respectively. As long as it is, it may be changed.
  • the circumferential distance D3 between the struts 411 changes, it greatly affects the bending rigidity of the neutral plane X2 (see FIG. 6) and is arranged at the position of the neutral plane X2 (see FIG. 6).
  • the distance D3 in the circumferential direction between the struts 411 at positions rotated 90 degrees from each of the first dense portion 42 and the second dense portion 43 is the largest. With such a configuration, the stent 4 is easily bent in a posture in which the first dense portion 42 and the second dense portion 43 are disposed on the neutral plane X2. That is, directivity can be given to the bending rigidity of the stent 4.
  • the plurality of circumferential portions 41 are arranged side by side along the direction of the axis X1 of the stent 4.
  • the plurality of first dense portions 42 are linearly along the axis X1 direction of the stent 4 over the plurality of surrounding portions 41.
  • the first dense portion 42 has a connecting portion 44.
  • the connecting portion 44 connects the surrounding portions 41 adjacent to each other in the axis X1 direction of the stent 4.
  • the surrounding portions 41 adjacent to each other in the axis X1 direction of the stent 4 are connected by the connecting portion 44 included in the first dense portion 42.
  • the plurality of second dense portions 43 are continuously linearly along the axis X1 direction of the stent 4 over the plurality of surrounding portions 41.
  • the second dense portion 43 has a connecting portion 44.
  • the connecting portion 44 connects the surrounding portions 41 adjacent to each other in the axis X1 direction of the stent 4.
  • the surrounding portions 41 adjacent to each other in the direction of the axis X ⁇ b> 1 of the stent 4 are connected by the connecting portion 44 included in the second dense portion 43.
  • the surrounding portions 41 adjacent to each other in the axis X1 direction of the stent 4 are connected by the connecting portion 44, so that the stent 4 has a cylindrical shape whose peripheral side surface is continuous in the axis X1 direction and exhibits a mesh shape. .
  • the stent 4 when the stent 4 passes through the living body lumen and is delivered to the target site, the stent 4 can pass through the living body lumen flexibly following the bending of the living body lumen. Is required. Further, the stent 4 is required to have strength (radial force: radial force) for maintaining the state in which the stenosis portion is expanded.
  • each of the plurality of rotating portions 41 has a plurality of first portions 45 and a plurality of second portions 46.
  • the plurality of first portions 45 are provided at positions facing each other with respect to the axis X1 of the stent 4 in the circumferential direction.
  • the plurality of second portions 46 are provided at positions facing each other with respect to the axis X1 of the stent 4 in the circumferential direction, and the rigidity of the strut 411 of the first portion 45 is in a state where at least a part of the plurality of surrounding portions 41 is bent. Less rigid.
  • the rigidity of the struts 411 in the second part 46 is smaller than the rigidity of the struts 411 in the first part 45 in a state in which at least a part of the plurality of circumferential portions 41 is bent.
  • the plurality of first portions 45 are continuously provided along the axis X1 direction of the stent 4 over the plurality of rotating portions 41 while maintaining a positional relationship facing each other with respect to the axis X1 of the stent 4 in the circumferential direction. Has been placed.
  • the bending stiffness when the stent 4 bends in a posture in which the first portion 45 is disposed at the position of the neutral plane X2 (see FIG. 6) is smaller than the bending stiffness when the stent 4 bends in another posture. Therefore, the stent 4 is easily bent in a posture in which the first portion 45 is disposed at the position of the neutral plane X2. That is, directivity can be given to the bending rigidity of the stent 4.
  • the “directivity” of the bending rigidity of the stent 4 means that the stent 4 has a relatively large rigidity in the strut 411 and a portion having a relatively large rigidity (the first portion 45 in the present embodiment).
  • the stent 4 having the directivity of bending rigidity has a portion that is relatively easily bent and a portion that is not easily bent in the strut 411 when bending.
  • the directivity of the stent 4 can be improved by increasing the difference between the rigidity of the portion having high rigidity and the rigidity of the portion having low rigidity in the strut 411. The stent 4 having such high directivity is surely bent in a posture where the bending rigidity is minimized.
  • the stent 4 since the stent 4 according to the present embodiment has high bending rigidity directivity, the stent 4 can pass through the bent portion of the living body lumen in a posture in which the bending rigidity is more surely minimized. Thereby, the passage property of the stent 4 in the living body lumen can be improved. Further, by giving directivity to the bending rigidity of the stent 4 without reducing the amount of the constituent material of the stent 4, the stent 4 can take a posture that is easy to bend. Thereby, the amount of struts 411 in the entire stent 4 can be secured, and the radial force required for the stent 4 can be maintained.
  • the circumferential portion 41 of the stent 4 has a first dense portion 42 in which the volume density of the struts 411 is higher than the volume density of the struts 411 in the second region 46, and the volume density of the struts 411. And a second dense portion 43 that is higher than the volume density of the struts 411 in the second portion 46.
  • the first dense portion 42 and the second dense portion 43 are provided at positions facing each other with respect to the axis X1 of the stent 4 in the circumferential direction.
  • the plurality of first dense portions 42 are continuously linearly extended along the axis X1 direction of the stent 4 over the plurality of surrounding portions 41.
  • the plurality of second dense portions 43 are continuously arranged on the straight line along the axis X1 direction of the stent 4 over the plurality of rotating portions 41.
  • the bending stiffness when the stent 4 bends in a posture in which the first dense portion 42 and the second dense portion 43 are arranged at the position of the neutral plane X2 is more than the bending stiffness when the stent 4 bends in another posture. small. Therefore, as indicated by an arrow A1 illustrated in FIG. 6, the stent 4 is easily bent in a posture in which the first dense portion 42 and the second dense portion 43 are disposed at the position of the neutral plane X2. That is, the directivity can be given to the bending rigidity of the stent 4 and the directivity of the bending rigidity of the stent 4 can be improved.
  • Bending stiffness is proportional to the cross-sectional second moment when the material is a single material and represents resistance to bending deformation. Therefore, when the material receives a bending moment, the material bends in a posture that minimizes the bending rigidity. Therefore, when the bending rigidity of the stent 4 has directivity, the member is easily bent in a posture in which the bending rigidity is minimized.
  • the stent 4 according to this embodiment can pass through the bent portion of the living body lumen in a posture in which the bending rigidity is more surely minimized. Thereby, the passage property of the stent 4 in the living body lumen can be improved.
  • the first dense portion 42 and the second dense portion 43 are disposed at the position of the neutral surface X ⁇ b> 2 that has little influence on the bending rigidity of the stent 4.
  • the first dense portion 42 and the second dense portion 43 in which the amount of the struts 411 forming the circumferential portion 41 of the stent 4 is larger than the amount of the struts 411 in the other portions are neutral surfaces. It is arranged at the position of X2. Thereby, the amount of struts 411 in the entire stent 4 can be secured, and the radial force required for the stent 4 can be maintained.
  • the circulating portion 41 is formed as a wave-like body in which the strut 411 has a plurality of bent portions.
  • the stent 4 can follow the bending of the living body lumen more flexibly and pass through the living body lumen. That is, the passability of the stent 4 in the living body lumen can be further improved.
  • the circumferential density (pitch) between the struts 411 is changed, so that the volume density of the struts 411 is higher than the volume density of the struts 411 in the second portion 46 and the first dense portions 42 and the first.
  • Two dense portions 43 are formed. Thereby, the 1st dense part 42 and the 2nd dense part 43 can be formed comparatively easily, and the passage nature of the stent 4 in a living body lumen can be improved, maintaining the radial force of the stent 4.
  • each of the first dense portion 42 and the second dense portion 43 has the connecting portion 44 that connects the circumferential portions 41 adjacent to each other in the axis X1 direction of the stent 4. Therefore, as compared with the case where the connecting portion 44 is not provided, the amount of the strut 411 in each of the first dense portion 42 and the second dense portion 43 is further larger than the amount of the strut 411 in the second portion 46. Thereby, the directivity of the bending rigidity of the stent 4 can be further improved, and the passage of the stent 4 in the living body lumen can be further improved while maintaining the radial force of the stent 4.
  • both the first dense portion 42 and the second dense portion 43 do not necessarily have the connecting portion 44.
  • only the first dense portion 42 may have the connecting portion 44.
  • only the second dense portion 43 may have the connecting portion 44. That is, it is sufficient that at least one of the first dense portion 42 and the second dense portion 43 has the connecting portion 44.
  • the connection part 44 does not need to connect all the surrounding parts 41 adjacent to each other in the axis X1 direction of the stent 4.
  • the connecting portions 44 included in each of the first dense portion 42 and the second dense portion 43 are provided alternately between the circumferential portions 41 adjacent to each other, and the connecting portions included in the first dense portion 42. 44 and the connecting portions 44 included in the second dense portion 43 may be alternately arranged along the axis X ⁇ b> 1 of the stent 4.
  • FIG. 7 is a development view showing the stent according to the first modification of the present embodiment.
  • the stent 4A according to the present modification includes a plurality of rotating portions 41A arranged side by side along the direction of the axis X1 (see FIGS. 2 and 3).
  • the orbiting portion 41A is formed as a wave-like body in which the strut 411 extends in the circumferential direction of the stent 4A and has a plurality of bent portions, and has a distal end side bent portion 412, a proximal end side bent portion 413, and a linear portion 414. .
  • the plurality of first portions 45A of the stent 4A includes a first dense portion 42A and a second dense portion 43A.
  • the length (amplitude) D4 of the strut 411 in the axis X1 direction at the first dense portion 42A is longer than the length D6 of the strut 411 in the axis X1 direction at the second portion 46A.
  • the volume density of the strut 411 in the first dense portion 42A is higher than the volume density of the strut 411 in the second portion 46A.
  • the length (amplitude) D5 of the strut 411 in the second dense portion 43A in the axis X1 direction is longer than the length D6 in the axis X1 direction of the strut 411 in the second portion 46A.
  • the volume density of the strut 411 in the 2nd dense part 43A is higher than the volume density of the strut 411 in the 2nd site
  • the “second portion 46A” means a rigidity smaller than the rigidity of the strut 411 of the first portion 45A in a state where at least a part of the plurality of rotating portions 41A is bent. It is a part which has and refers to parts other than the 1st site
  • the amplitude D6 of the strut 411 in the second portion 46A only needs to be shorter than the amplitude D4 of the strut 411 of the first dense portion 42A and the amplitude D5 of the strut 411 of the second dense portion 43A, and changes. You may do it.
  • the amplitude D6 of the strut 411 changes, it greatly affects the magnitude of the bending rigidity in the neutral plane X2, and from each of the first dense portion 42A and the second dense portion 43A arranged at the position of the neutral plane X2. It is preferable that the amplitude D6 of the strut 411 at the position rotated by 90 degrees is the shortest.
  • the stent 4A is easily bent in a posture in which the first dense portion 42A and the second dense portion 43A are disposed on the neutral plane X2. That is, directivity can be given to the bending rigidity of the stent 4A.
  • the length (amplitude) of the strut 411 in the axis X1 direction of the stent 4A changes, so that the volume density of the strut 411 is larger than the volume density of the strut 411 in the second portion 46A.
  • a high first dense portion 42A and a second dense portion 43A are formed.
  • the first dense portion 42A and the second dense portion 43A can be formed relatively easily, and the passage of the stent 4A in the living body lumen can be improved while maintaining the radial force of the stent 4A.
  • the same effects as those described above with reference to FIGS. 4 to 6 can be obtained.
  • FIG. 8 is a development view showing the stent according to the second modification of the present embodiment.
  • the stent 4B according to the present modification includes a plurality of rotating portions 41B arranged side by side along the direction of the axis X1 (see FIGS. 2 and 3).
  • the circumferential portion 41B is formed as a wave-like body in which the strut 411 extends in the circumferential direction of the stent 4B and has a plurality of bent portions, and has a distal end side bent portion 412, a proximal end side bent portion 413, and a linear portion 414. .
  • the plurality of first portions 45B of the stent 4B includes a first dense portion 42B and a second dense portion 43B.
  • the line width D7 of the strut 411 in the first dense portion 42B is thicker than the line width D9 of the strut 411 in the second portion 46B.
  • the volume density of the strut 411 in the 1st dense part 42B is higher than the volume density of the strut 411 in the 2nd site
  • the line width D8 of the strut 411 in the second dense portion 43B is larger than the line width D9 of the strut 411 in the second portion 46B.
  • the volume density of the strut 411 in the 2nd dense part 43B is higher than the volume density of the strut 411 in the 2nd site
  • the “second portion 46B” means a rigidity smaller than the rigidity of the strut 411 of the first portion 45B in a state where at least a part of the plurality of rotating portions 41B is bent. It is a part which has, and says parts other than the 1st site
  • the line width D9 of the strut 411 in the second portion 46B only needs to be narrower than the line widths D7 and D8 of the strut 411 in each of the first dense portion 42B and the second dense portion 43B, and changes. You may do it.
  • the line width D9 of the strut 411 changes, the magnitude of the bending rigidity in the neutral plane X2 is greatly affected, and each of the first dense portion 42B and the second dense portion 43B disposed at the position of the neutral plane X2 It is preferable that the line width D9 of the strut 411 at a position rotated 90 degrees from the narrowest is the narrowest.
  • the stent 4B is easily bent in a posture in which the first dense portion 42B and the second dense portion 43B are disposed on the neutral plane X2. That is, directivity can be given to the bending rigidity of the stent 4B.
  • a portion 43B is formed.
  • the 1st dense part 42B and the 2nd dense part 43B can be formed comparatively easily, and the passage nature of stent 4B in a living body lumen can be improved, maintaining the radial force of stent 4B.
  • the same effects as those described above with reference to FIGS. 4 to 6 can be obtained.
  • FIG. 9 is a cross-sectional view illustrating a contracted state of the stent according to the third modification of the present embodiment.
  • FIG. 9 corresponds to a cross-sectional view of the stent taken along section plane C1-C1 shown in FIG.
  • the stent 4C according to the present modification includes a plurality of rotating portions 41C arranged side by side along the direction of the axis X1 (see FIGS. 2 and 3).
  • the circumferential portion 41C is formed as a wave-like body in which the strut 411 extends in the circumferential direction of the stent 4C and has a plurality of bent portions, and includes a distal end side bent portion 412 (see FIG. 4) and a proximal end side bent portion 413 (see FIG. 4). And a linear portion 414 (see FIG. 4).
  • the plurality of first portions 45C of the stent 4C according to this modification includes a first dense portion 42C and a second dense portion 43C.
  • the thickness (diameter length) t1 of the strut 411 in the first dense portion 42C is thicker than the thickness t3 of the strut 411 in the second portion 46C.
  • the volume density of the strut 411 in the first dense portion 42C is higher than the volume density of the strut 411 in the second portion 46C.
  • the thickness t2 of the strut 411 in the second dense portion 43C is thicker than the thickness t3 of the strut 411 in the second portion 46C.
  • the volume density of the strut 411 in the 2nd dense part 43C is higher than the volume density of the strut 411 in the 2nd site
  • the “second portion 46C” means a rigidity smaller than the rigidity of the strut 411 of the first portion 45C in a state where at least a part of the plurality of rotating portions 41C is bent. It is a part which has, and says parts other than the 1st site
  • the thickness t3 of the strut 411 changes, the bending rigidity at the neutral plane X2 is greatly affected, and each of the first dense portion 42C and the second dense portion 43C disposed at the position of the neutral plane X2 It is preferable that the thickness t3 of the strut 411 at the position rotated 90 degrees from the smallest is the thinnest. With such a configuration, the stent 4C is easily bent in a posture in which the first dense portion 42C and the second dense portion 43C are disposed on the neutral plane X2. That is, directivity can be given to the bending rigidity of the stent 4C.
  • the thickness (the length in the radial direction) of the strut 411 is changed, so that the first density is higher than the volume density of the strut in the second portion 46C.
  • a portion 42C and a second dense portion 43C are formed.
  • the first dense portion 42C and the second dense portion 43C are formed by the change in the thickness of the strut 411, and the passage of the stent 4C in the living body lumen can be improved while maintaining the radial force of the stent 4C. it can.
  • the same effects as those described above with reference to FIGS. 4 to 6 can be obtained.
  • FIG. 10 is a developed view showing a stent according to a fourth modification of the present embodiment.
  • the stent 4D according to this modification includes a plurality of rotating portions 41D arranged side by side along the direction of the axis X1 (see FIGS. 2 and 3).
  • the orbiting portion 41D is formed as a wave-like body in which the strut 411 extends in the circumferential direction of the stent 4D and has a plurality of bent portions, and has a distal end side bent portion 412, a proximal end side bent portion 413, and a linear portion 414. .
  • the plurality of first portions 45D of the stent 4D according to this modification include a first dense portion 42D and a second dense portion 43D.
  • the first dense portion 42D has the connecting portion 44 described above with reference to FIGS. Therefore, the amount of struts 411 in the first dense portion 42D is larger than the amount of struts 411 in the second portion 46D. Thereby, the volume density of the strut 411 in the 1st dense part 42D is higher than the volume density of the strut 411 in the 2nd site
  • the second dense portion 43D has the connecting portion 44 described above with reference to FIGS. Therefore, the amount of struts 411 in the second dense portion 43D is larger than the amount of struts 411 in the second portion 46D. Thereby, the volume density of the strut 411 in the 2nd dense part 43D is higher than the volume density of the strut 411 in the 2nd site
  • each of the first dense portion 42D and the second dense portion 43D has the connecting portion 44, and thus the first dense portion 42D and the second dense portion 42D.
  • the amount of struts 411 in each of the dense portions 43D is larger than the amount of struts 411 in the second portion 46D.
  • the connecting portion 44 connects all the surrounding portions 41D adjacent to each other in the axis X1 direction of the stent 4D. Therefore, directivity can be given to the bending rigidity of the stent 4D. Further, with respect to other effects, the same effects as those described above with reference to FIGS. 4 to 6 can be obtained.
  • FIG. 11 is a developed view showing a stent according to a fifth modification of the present embodiment.
  • the stent 4E according to this modification includes a plurality of circumferential portions 41E arranged side by side along the direction of the axis X1 (see FIGS. 2 and 3).
  • the circumferential portion 41E is formed as a wave-like body in which the strut 411 extends in the circumferential direction of the stent 4E and has a plurality of bent portions, and has a distal end side bent portion 412, a proximal end side bent portion 413, and a linear portion 414. .
  • the plurality of first portions 45E of the stent 4E according to this modification include a first dense portion 42E and a second dense portion 43E.
  • the connecting portions 44 included in the first dense portions 42E are provided alternately between the surrounding portions 41E adjacent to each other in the axis X1 direction of the stent 4E.
  • the connection part 44 which the 2nd dense part 43E has is provided every other between the surrounding parts 41E mutually adjacent in the axis
  • the connection part 44 which the 1st dense part 42E has, and the connection part 44 which the 2nd dense part 43E has are alternately arrange
  • the connecting portions 44 included in the first dense portion 42E and the connecting portions 44 included in the second dense portion 43E are alternately arranged along the axis X1 of the stent 4E.
  • the stent 4E according to this modification is different from the stent 4D described above with reference to FIG.
  • the other structure is the same as the stent 4D described above with reference to FIG.
  • the connecting portions 44 are provided alternately between the surrounding portions 41E adjacent to each other in the axis X1 direction of the stent 4E, the flexibility with respect to the bending of the biological lumen is provided. While ensuring, directivity can be given to the bending rigidity of the stent 4E. As for other effects, the same effects as those described above with reference to FIGS. 4 to 6 and 10 can be obtained.
  • FIG. 12 is a developed view showing a stent according to a sixth modification of the present embodiment.
  • the orbiting portion 41F of the stent 4F according to this modification is a spiral body in which the struts 411 extend spirally. That is, in the stent 4F illustrated in FIG. 12, the lower end portion (the end portion at the 0 degree position) of the orbiting portion 41F is the adjacent orbiting portion 41F (the adjacent orbiting portion on the left in FIG. 12) in the axis X1 direction of the stent 4F. 41F) is connected to the upper end portion (the end portion at a position of 360 degrees).
  • the surrounding portions 41F adjacent to each other in the axis X1 direction of the stent 4F are connected as a spiral body, so that the stent 4F has a cylindrical shape whose peripheral side surface is continuous in the axis X1 direction and exhibits a spiral shape. .
  • the plurality of first portions 45F of the stent 4F includes a first dense portion 42F and a second dense portion 43F.
  • the circumferential distance D11 between the struts 411 in the first dense portion 42F is narrower than the circumferential distance D12 between the struts 411 in the second part 46F.
  • the volume density of the strut 411 in the 1st dense part 42F is higher than the volume density of the strut 411 in the 2nd site
  • the circumferential interval D11 between the struts 411 in the second dense portion 43F is narrower than the circumferential interval D12 between the struts 411 in the second portion 46F.
  • the volume density of the strut 411 in the 2nd dense part 43F is higher than the volume density of the strut 411 in the 2nd site
  • the “second portion 46F” means a rigidity smaller than the rigidity of the strut 411 of the first portion 45F in a state in which at least a part of the plurality of rotating portions 41F is bent. It is a part which has, and says parts other than the 1st site
  • the orbiting portion 41F is a spiral body, the orbiting portion 41F is spirally continuous even if a connecting portion that connects the adjacent surrounding portion 41F is not provided. is doing.
  • the first dense portion 42F and the second dense portion 43F are provided at positions facing each other with respect to the axis X1 of the stent 4 in the circumferential direction. Thereby, the stent 4F can improve the passage property in a living body lumen, maintaining a radial force.
  • the surrounding portion 41 of the stent 4 described above with reference to FIGS. 4 to 6 is a spiral body is taken as an example.
  • the present invention is not limited to this, and the orbiting portions 41A, 41B, and 41C of the stents 4A, 4B, and 4C described above with reference to FIGS. 7 to 9 may be formed as a spiral body. Even in this case, the same effect can be obtained.
  • FIG. 13 is a developed view showing a stent according to a seventh modification of the present embodiment.
  • the stent 4G according to this modification includes a plurality of rotating portions 41G arranged side by side along the direction of the axis X1 (see FIGS. 2 and 3).
  • the circumferential portion 41G is formed as a wave-like body in which the strut 411 extends in the circumferential direction of the stent 4G and has a plurality of bent portions, and has a distal end side bent portion 412, a proximal end side bent portion 413, and a linear portion 414. .
  • the orbiting portion 41G of the stent 4G has a plurality of first portions 45G and a plurality of second portions 46G.
  • the plurality of first portions 45G are spirally arranged along the axis X1 direction of the stent 4G over the plurality of surrounding portions 41G while maintaining a positional relationship facing each other with respect to the axis X1 of the stent 4G in the circumferential direction. ing.
  • the plurality of first portions 45G have a first dense portion 42G and a second dense portion 43G.
  • the plurality of first dense portions 42G are continuously spiraled along the axis X1 direction of the stent 4G over the plurality of surrounding portions 41G. Is arranged.
  • the circumferential angle between one first dense portion 42G and the other first dense portion 42G is 45 degrees.
  • the angle in the circumferential direction between one first dense portion 42G and the other first dense portion 42G is not limited to 45 degrees, and may be 30 degrees, for example, 60 degrees. May be.
  • the plurality of second dense portions 43G are spirally continuous along the axis X1 direction of the stent 4G over the plurality of surrounding portions 41G.
  • the circumferential angle between one second dense portion 43G and the other second dense portion 43G is 45 degrees.
  • the circumferential angle between one second dense portion 43G and the other second dense portion 43G is not limited to 45 degrees, and may be, for example, 30 degrees, for example, 60 degrees. May be.
  • the plurality of first portions 45G spirals along the axis X1 direction of the stent 4G over the plurality of rotating portions 41G in a state in which the positional relationship facing each other with respect to the axis X1 of the stent 4G is maintained in the circumferential direction.
  • the stent 4G according to the present embodiment is different from the stent 4 described above with reference to FIGS.
  • Other structures are similar to the stent 4 described above with respect to FIGS.
  • the neutral plane X2 (see FIG. 6) when the stent 4G is bent is formed in a spiral shape along the axis X1 direction of the stent 4G. Therefore, the stent 4G is easily bent in a posture in which the first portion 45G is disposed at the position of the neutral surface X2 formed in a spiral shape. That is, the neutral plane X2 of the stent 4G changes along each of the plurality of rotating portions 41G along the direction of the axis X1.
  • the stent 4G when the stent 4G passes through a meandering blood vessel portion, the stent 4G can pass through the blood vessel portion while taking a posture in which the bending rigidity is locally minimized with respect to the blood vessel portion. Thereby, the passage of the stent 4G in the living body lumen is further improved.
  • FIG. 14 is a cross-sectional view showing a tube for producing a stent according to an eighth modification of the present embodiment. Note that FIG. 14 corresponds to a cross-sectional view taken along a plane perpendicular to the axis of the stent.
  • the stent according to the present embodiment is manufactured by processing, for example, a tube or a pipe.
  • a stent is partially removed by cutting (for example, mechanical cutting, laser cutting), chemical etching, or the like on a side surface of a synthetic resin tube or a metal tube, and a plurality of notches are formed on the side surface.
  • it is produced by forming a plurality of openings.
  • a tube 5 shown in FIG. 14 is an example of a tube for producing a stent according to this modification.
  • the tube 5 is formed in a cylindrical shape or a tubular shape by, for example, a biodegradable biodegradable polymer, and includes a first forming portion 51 and a second forming portion 52.
  • the first forming portion 51 is a portion that becomes the first portion of the strut (for example, the first portion 45 described above with reference to FIG. 4) after the stent according to the present modification is manufactured.
  • the second formation portion 52 is a portion that becomes the second portion of the strut (for example, the second portion 46 described above with reference to FIG. 4) after the stent according to the present modification is manufactured.
  • the material property of the first formation part 51 is different from the material property of the second formation part 52.
  • the tube 5 is formed by extrusion molding using different biodegradable polymers at the first forming portion 51 and the second forming portion 52.
  • the material of the first formation site 51 include polylactic acid.
  • the material of the second formation site 52 include polycaprolactan.
  • the tube 5 is formed in a cylindrical shape or a tubular shape from a metal having biocompatibility, and has a first forming portion 51 and a second forming portion 52. Even in this case, the material characteristics of the first formation site 51 are different from the material characteristics of the second formation site 52. For example, heat treatment such as annealing is performed on at least one of the first formation portion 51 and the second formation portion 52. Alternatively, for example, processing such as shot peening is performed on at least one of the first formation portion 51 and the second formation portion 52.
  • part differs from the material property of the strut of the 2nd site
  • the tube 5 may have a structure in which different metals are bonded to each other at the first forming portion 51 and the second forming portion 52.
  • examples of the material of the first forming portion 51 include stainless steel.
  • An example of the material of the second formation portion 52 is gold.
  • the tube 5 may have a structure in which a metal and a biodegradable polymer are bonded to each other at the first formation site 51 and the second formation site 52.
  • the material of the strut of the first part Because the properties are different from the material properties of the struts in the second part, the stiffness of the struts in the second part is different from the rigidity of the struts in the first part. Specifically, it is possible to make the rigidity of the struts of the second part smaller than the rigidity of the struts of the first part in a state where at least some of the plurality of circulation parts are bent. Accordingly, the first portion and the second portion are formed by the difference in the material characteristics of the strut, and the passage of the stent in the living body lumen can be improved while maintaining the radial force of the stent.
  • the present invention has been described above. However, the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the claims. A part of the configuration of the above embodiment can be omitted, or can be arbitrarily combined so as to be different from the above. For example, in the description of the present embodiment, the direction of the bending rigidity is given to the stent by changing the strut or the connecting portion of the stent. However, the present invention is not limited to this.
  • the struts or connecting portions of the stent do not change, and by providing a member that continuously extends and is fixed on the outer circumference of the stent over the entire length of the stent, the direction of the bending rigidity is given to the stent. May be.
  • 2 ... Stent delivery system, 3 ... Balloon catheter, 4, 4A, 4B, 4C, 4D, 4E, 4F, 4G ... Stent, 5 ... Tube, 31 ... Shaft body, 32 ... Balloon, 32a ... Tip side joint, 32b ... Base end side joint, 32c ... Expansion space, 41, 41A, 41B, 41C, 41D, 41E, 41F, 41G ... Circulation 42, 42A, 42B, 42C, 42D, 42E, 42F, 42G ... first dense part, 43, 43A, 43B, 43C, 43D, 43E, 43F, 43G ... second dense part, 44.

Landscapes

  • Health & Medical Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Biomedical Technology (AREA)
  • Heart & Thoracic Surgery (AREA)
  • Optics & Photonics (AREA)
  • Cardiology (AREA)
  • Oral & Maxillofacial Surgery (AREA)
  • Transplantation (AREA)
  • Physics & Mathematics (AREA)
  • Vascular Medicine (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Animal Behavior & Ethology (AREA)
  • General Health & Medical Sciences (AREA)
  • Public Health (AREA)
  • Veterinary Medicine (AREA)
  • Media Introduction/Drainage Providing Device (AREA)

Abstract

Le problème décrit par la présente invention est de fournir un stent grâce auquel il est possible d'améliorer le passage dans une lumière d'un corps vivant tout en maintenant une force radiale. La solution selon l'invention porte sur un stent (4) qui comprend une pluralité de parties d'enroulement (41) comprenant des entretoises linéaires (411) formées selon une forme tubulaire et s'enroulant autour d'un axe. La pluralité de parties d'enroulement (41) sont disposées côte à côte le long de la direction axiale. Chacune de la pluralité de parties d'enroulement (41) présente une pluralité de premières parties (45) disposées à des positions opposées les unes aux autres par rapport à l'axe dans la direction circonférentielle, et une pluralité de secondes parties (46) ayant une rigidité inférieure à la rigidité des entretoises (411) des premières parties (45) dans un état dans lequel au moins une partie de la pluralité de parties d'enroulement (41) sont courbées, les secondes parties étant disposées à des positions opposées les unes aux autres par rapport à l'axe dans la direction circonférentielle. La pluralité de premières parties (45) sont disposées de façon continue le long de la direction axiale à travers la pluralité de parties d'enroulement (41) dans un état qui maintient les relations de position opposées les unes aux autres par rapport à l'axe dans la direction circonférentielle.
PCT/JP2018/009100 2017-05-17 2018-03-08 Stent Ceased WO2018211796A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2017-098300 2017-05-17
JP2017098300A JP2020124232A (ja) 2017-05-17 2017-05-17 ステント

Publications (1)

Publication Number Publication Date
WO2018211796A1 true WO2018211796A1 (fr) 2018-11-22

Family

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Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2018/009100 Ceased WO2018211796A1 (fr) 2017-05-17 2018-03-08 Stent

Country Status (2)

Country Link
JP (1) JP2020124232A (fr)
WO (1) WO2018211796A1 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2023046301A1 (fr) * 2021-09-27 2023-03-30 Angiomed Gmbh & Co.Medizintechnik Kg Implant et son procédé de fabrication

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH06181993A (ja) * 1991-10-28 1994-07-05 Advanced Cardeovascular Syst Inc 膨張可能なステント及びその製造方法
JP2001509702A (ja) * 1997-01-13 2001-07-24 ゴア エンタープライズ ホールディングス，インコーポレイティド 薄型断面形状の自己拡張式脈管ステント
WO2008112057A2 (fr) * 2007-03-09 2008-09-18 Boston Scientific Limited Modèle de stent avec des entretoises présentant des angles et une rigidité différents
JP2008237880A (ja) * 2007-01-08 2008-10-09 Cordis Corp 周囲において変化する軸方向の可撓性を有する管腔内医療装置
JP2015156967A (ja) * 2014-02-24 2015-09-03 テルモ株式会社 ステントデリバリーシステム

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH06181993A (ja) * 1991-10-28 1994-07-05 Advanced Cardeovascular Syst Inc 膨張可能なステント及びその製造方法
JP2001509702A (ja) * 1997-01-13 2001-07-24 ゴア エンタープライズ ホールディングス，インコーポレイティド 薄型断面形状の自己拡張式脈管ステント
JP2008237880A (ja) * 2007-01-08 2008-10-09 Cordis Corp 周囲において変化する軸方向の可撓性を有する管腔内医療装置
WO2008112057A2 (fr) * 2007-03-09 2008-09-18 Boston Scientific Limited Modèle de stent avec des entretoises présentant des angles et une rigidité différents
JP2015156967A (ja) * 2014-02-24 2015-09-03 テルモ株式会社 ステントデリバリーシステム

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2023046301A1 (fr) * 2021-09-27 2023-03-30 Angiomed Gmbh & Co.Medizintechnik Kg Implant et son procédé de fabrication

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