WO2012020812A1 - ステント - Google Patents
ステント Download PDFInfo
- Publication number
- WO2012020812A1 WO2012020812A1 PCT/JP2011/068314 JP2011068314W WO2012020812A1 WO 2012020812 A1 WO2012020812 A1 WO 2012020812A1 JP 2011068314 W JP2011068314 W JP 2011068314W WO 2012020812 A1 WO2012020812 A1 WO 2012020812A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- stent
- alloy
- nickel
- main
- cobalt
- Prior art date
Links
Images
Classifications
-
- 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
-
- 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 sheet material or tubes, e.g. perforated by laser cuts or etched holes
-
- 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 sheet material 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 sheet material or tubes, e.g. perforated by laser cuts or etched holes with bands having a meander structure, adjacent bands being connected to each other
-
- A—HUMAN NECESSITIES
- A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
- A61L—METHODS OR APPARATUS FOR STERILISING MATERIALS OR OBJECTS IN GENERAL; DISINFECTION, STERILISATION OR DEODORISATION OF AIR; CHEMICAL ASPECTS OF BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES; MATERIALS FOR BANDAGES, DRESSINGS, ABSORBENT PADS OR SURGICAL ARTICLES
- A61L31/00—Materials for other surgical articles, e.g. stents, stent-grafts, shunts, surgical drapes, guide wires, materials for adhesion prevention, occluding devices, surgical gloves, tissue fixation devices
- A61L31/02—Inorganic materials
- A61L31/022—Metals or alloys
-
- 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 sheet material 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 sheet material or tubes, e.g. perforated by laser cuts or etched holes with bands having a meander structure, adjacent bands being connected to each other
- A61F2002/9155—Adjacent bands being connected to each other
- A61F2002/91575—Adjacent bands being connected to each other connected peak to trough
-
- 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
- A61F2230/00—Geometry of prostheses classified in groups A61F2/00 - A61F2/26 or A61F2/82 or A61F9/00 or A61F11/00 or subgroups thereof
- A61F2230/0002—Two-dimensional shapes, e.g. cross-sections
- A61F2230/0004—Rounded shapes, e.g. with rounded corners
- A61F2230/0013—Horseshoe-shaped, e.g. crescent-shaped, C-shaped, U-shaped
Definitions
- the present invention relates to a stent that is placed in a stenosis portion in a body cavity such as a blood vessel, gallbladder, esophagus, intestine, and ureter.
- a stent is used together with, for example, a balloon catheter.
- a stenosis occurs in a body cavity such as a blood vessel
- the stent is placed after the stenosis is expanded by a balloon catheter, supporting the inner wall of the body cavity from the inside and causing restenosis. Used to prevent.
- the stent is attached to the outside of the deflated balloon part in a reduced diameter state, and is inserted into the body cavity together with the balloon part.
- the stent is also inflated by inflating the balloon part, and the stenosis part is expanded and indwelled while maintaining the stent expanded state, and only the balloon catheter is withdrawn.
- patent document 1 and patent document 2 are proposed, for example.
- Patent Document 1 has a lower limit of proof stress as low as 300 MPa, and the upper limit is not shown, so there is anxiety in practicality, and because it is manufactured by laser processing, There are problems such as the occurrence of brittleness due to annealing and thermal deformation under the influence of heat, and the need for deburring and polishing processes, making the manufacturing process complicated.
- the stent described in Patent Document 2 is manufactured by electroforming that is easier to manufacture than laser processing.
- the yield strength is poor only with gold exemplified as a metal by electroforming, there is a problem that there is a problem in practicality when used as a stent.
- the present invention pays attention to the above problems and succeeds in depositing various alloys by electrolytic deposition in a metal ion solution, and is different from ordinary materials, that is, metal materials obtained by melting and rolling with high temperature.
- An alloy electroformed material with excellent mechanical properties and corrosion resistance was obtained. Therefore, it is a practically extremely useful stent that has an excellent yield strength (elastic limit stress), has a high fatigue strength that can withstand the pulsation of the heart, and does not elute metal ions into any body fluid or electrolyte.
- the purpose is to provide.
- the stent according to the first aspect of the present invention is a radially expandable cylindrical shape that is placed in the lumen of a living body, and includes a main stent element formed on a cylindrical virtual surface. It is made from an alloy having a proof stress of 500 to 2,700 MPa.
- the lower limit value of the proof stress of the stent element is 500 MPa, which is larger than 300 MPa of the stent described in Patent Document 1, and the upper limit value is 2,700 MPa, even a very thin stent can withstand external pressure.
- the cross-sectional area of the blood vessel is not sacrificed, and it can be easily and uniformly expanded in the radial direction, and is not easily collapsed in the radial direction after expansion. Is.
- the stent according to the second aspect of the present invention is a radially expandable cylindrical stent placed in the lumen of a living body, comprising a main stent element formed on a cylindrical virtual surface.
- the stent elements are made from nickel or an alloy having higher fatigue strength than nickel / cobalt alloys.
- the fatigue strength of the main stent element is an alloy having a strength 1.5 times or more that of nickel or a nickel / cobalt alloy. As described above, it is intended to have a higher fatigue strength than a stent conventionally made of nickel or a nickel / cobalt alloy by electroforming, and preferably has a fatigue strength of 1.5 times or more. It is a thing.
- the main stent element is made of an electroformed alloy containing any of gold, silver, copper, nickel, cobalt, and palladium.
- the material with extremely high fatigue strength can be made by electroforming, so it is most suitable for stents at sites where vibration is always applied, and can be expanded easily and uniformly in the radial direction. Later, they are not easily crushed in the radial direction.
- the stent according to the fifth aspect of the present invention includes a sulfate, chloride, ammonia complex, cyanide complex, amine complex, sulfamine salt, hypophosphite, pyrophosphate, tartrate, or EDTA compound.
- a stent having high yield strength and fatigue strength is produced by using the selected compound as an additive.
- the main stent element is formed by electroforming using gold as a main component and using at least one alloy selected from silver, copper, palladium, nickel, and cobalt. It was produced.
- the main stent element is formed by electroforming using at least one alloy selected from gold, silver, copper, nickel, and cobalt, with the main component being palladium. It was produced.
- the above-mentioned problem of the stent described in Patent Document 2 is solved by selecting an alloy that can improve fatigue strength by greatly improving the yield strength and producing it by electroforming.
- the stent according to the eighth aspect of the present invention is provided with a joint for forming a cylindrical shape.
- a joint for forming a cylindrical shape.
- the stent according to the ninth aspect of the present invention is such that a joint for forming the main stent element into a cylindrical shape is joined by electrodeposition.
- the electrodeposition method since the electrodeposition method is used, no heat is applied at the time of joining, so that there is no annealing due to heat or brittleness due to thermal deformation, and the joint can maintain the same gloss as the material. Therefore, the appearance is smooth, which is convenient when the stent is inserted into the lumen of a living body.
- the main stent element is composed of a plurality of cells and a connecting portion that connects the cells, and the cell has a wire diameter of 10 to 50 ⁇ m and the connecting portion has a wire diameter of 5 to 20 ⁇ m.
- the cell wire diameter that is, the thickness of the stent is set to 10 to 50 ⁇ m, so that the thickness of the stent is less than 60 ⁇ m described in Patent Document 1. Therefore, even if the stent is placed in the blood vessel.
- the stent does not interfere with blood flow and blood flow does not deteriorate, and the wire diameter of the connecting part is reduced to 5 to 20 ⁇ m, so if the blood vessel meanders like a wave, the connecting part also bends and the cell Is designed to reliably support the inner wall of the blood vessel from the inside.
- the main stent formed in the cylindrical virtual surface has a cylindrical shape expandable in the radial direction and is placed in the lumen of the living body.
- the stent element is made of an alloy having a proof stress of 500 to 2,700 MPa
- the lower limit value of the proof stress of the stent element is 500 MPa, which is larger than 300 MPa of the stent described in Patent Document 1, and the upper limit value.
- the stent of the second aspect is a radially expandable cylindrical stent that is placed in the lumen of a living body, and includes a main stent element formed on a cylindrical virtual surface.
- the element was made of nickel or an alloy having higher fatigue strength than nickel / cobalt alloy, and the fatigue strength was at least 1.5 times the strength as in the third embodiment.
- it can be easily and uniformly expanded in the radial direction, and can be excellently prevented from being easily collapsed in the radial direction after expansion.
- the main stent element is made of an electroformed alloy containing any of gold, silver, copper, nickel, cobalt, and palladium, a material having extremely high fatigue strength is made by electroforming. It is possible to obtain an excellent effect of being able to.
- a compound of any one of sulfate, chloride, ammonia complex, cyanide complex, amine complex, sulfamine salt, hypophosphite, pyrophosphate, tartrate, EDTA is added.
- the main stent element is produced by electroforming using gold as a main constituent and using at least one alloy selected from silver, copper, palladium, nickel, and cobalt. Therefore, there is no metal ion elution in all body fluids and electrolytes, and the excellent effect that there is no adverse effect on the lumen of the living body can be reliably obtained.
- the main stent element is produced by electroforming using at least one alloy selected from gold, silver, copper, nickel, and cobalt with palladium as the main constituent. Therefore, there is no metal ion elution in all body fluids and electrolytes, and the excellent effect that there is no adverse effect on the lumen of the living body can be reliably obtained.
- a joint for forming a cylindrical shape is provided. After the stent is produced in a planar shape, the joint is rounded into a cylindrical shape and the joint is subjected to electric resistance welding or laser. By joining by welding etc., the outstanding effect that productivity and quality can be improved can be acquired.
- connection portion of the main stent element is connected by electrodeposition, heat is not applied at the time of joining, so that annealing due to heat, brittleness due to thermal deformation, and the like occur.
- the joint can maintain the same gloss as the material, the appearance can be made smooth, and an excellent effect that the stent can be smoothly inserted into the lumen of the living body can be obtained.
- the main stent element is composed of a plurality of cells and a connecting portion that connects the cells, and the cell has a wire diameter of 10 to 50 ⁇ m and the connecting portion has a wire diameter of 5 to 20 ⁇ m. Therefore, the cell diameter, that is, the thickness of the stent can be reduced to 10 to 50 ⁇ m, and even if the stent is placed in the blood vessel, the stent does not disturb the blood flow and the blood flow does not deteriorate.
- the wire diameter of the connecting part can be made as thin as 5 to 20 ⁇ m, and if the blood vessel meanders like a wave, the connecting part also follows and bends, and the cell is firmly supported from the inside of the blood vessel in close contact with the inner wall of the blood vessel It is possible to reliably obtain the excellent effect of being able to.
- reference numeral 1 denotes a radially expandable cylindrical stent placed in the lumen of a living body, and has a main stent element 2 formed on a cylindrical virtual surface.
- the main stent element 2 includes nine cells 3 and connecting portions 4 that connect the cells 3 to each other.
- the cell 3 has a wire diameter of 10 to 30 ⁇ m
- the connecting portion 4 has a wire diameter of 5 to 9 ⁇ m.
- the connecting portion 4 is bent in a meandering manner to enhance the bendability.
- the stent 1 is made in a plane as shown in FIG. 2 and is rounded into a cylindrical shape as shown in FIG. 1 to form a cylinder by electrodeposition. After the mandrel is coated with a resist, the stent 1 may be manufactured by exposing it to a cylindrical shape and performing etching.
- the main stent element 2 includes gold as a main component, and at least one alloy selected from silver, copper, palladium, nickel, and cobalt, or palladium as a main component, and includes gold, silver, copper, nickel, Using at least one alloy selected from cobalt, it is produced by electroforming as follows.
- a plurality of cells 3 are produced by performing the first deposition on the removed portion by electroforming the above-described alloy.
- a resist is coated on the substrate and a photomask is placed again, and then exposed to ultraviolet rays to be removed by exposure, and the above-described alloy is applied to the removed portion.
- the second precipitation is performed by electroforming, and the connecting portion 4 is produced.
- the cell 3 and the connecting portion 4 are exposed so that a part thereof is connected to each other, and then electrodeposited, and as a result, a connected body is obtained.
- the plurality of cells 3 and the connecting portions 4 are integrally formed of the above-described alloy, and the main stent element 2 is manufactured as shown in FIG.
- the first deposition shape and the second deposition metal shape can be arbitrarily changed. That is, the difference in width and thickness is, for example, that the width depends on the width at the time of photomask fabrication, and the thickness of the shape can depend on the deposition electrolysis time. It is possible to freely change the thickness and width of a partial portion as required, with extremely accuracy. Thus, the ability to control the thickness and width freely and accurately makes it possible to give the stent 1 a high function that has never been obtained, which is completely obtained with a conventional stent processed with a laser or the like. It is a big feature that cannot be done.
- joining can be performed by electric resistance welding, laser welding, or the like, but it is preferable to join in accordance with the joining process of FIGS. 4A to 4D. That is, as shown in FIG. 4A, after joining the joining portion 5A and the joining portion 5B close to each other as shown in FIG. 4B, paint and non-conductive tape other than the overlapped portion are shown in the sectional view of FIG. 4C.
- the masking 6 is applied, and then the additional electro-deposition with the same electroformed alloy 7 as the stent 1 and the masking 6 is removed as shown in FIG. 4D, so that the joining process between the joint 5A and the joint 5B is as follows. finish.
- this joining method since heat is not applied at the time of joining, there is no annealing due to heat, brittleness due to thermal deformation, etc., and the joining parts 5A and 5B can maintain the same gloss as the material, so that the appearance is It is smooth and convenient when the stent 1 is inserted into a body cavity such as a blood vessel.
- FIG. 5 is a graph showing the measurement results of the proof stress (elastic limit stress) of the stent 1, where the horizontal axis represents strain (%) and the vertical axis represents stress (MPa).
- A shows a case where an alloy of 40% nickel and 60% palladium is used as an alloy of the main stent element 2
- B shows a case where an alloy of 80% nickel and 20% cobalt is used as a conventional alloy. It was confirmed that the proof stress of the stent 1 according to the present invention was as extremely large as 500 MPa from B to 2,700 MPa from A.
- FIG. 6 is a graph showing the measurement results of fatigue strength.
- the horizontal axis represents the number of repetitions (times), and the vertical axis represents the maximum stress (MPa).
- C is according to the present invention, and when an alloy of 40% nickel and 60% palladium is used as the alloy of the main stent element 2, D and E are conventional materials, D is a nickel / cobalt alloy, E is This shows the case where nickel is used.
- the maximum stress is 1,000 MPa
- D is cut when it is repeated 700,000 times
- E is cut when it is repeated 50,000 times
- C according to the present invention is cut. Was not cut even after repeated 10 million times, and it was confirmed that the fatigue strength was 1.5 to 14 times or more that of conventional nickel / cobalt alloys and nickel.
- the metal that can be electroformed is limited, and a typical example of a metal that cannot be electroformed even if it can be plated is chromium. This is due to metal ions or metal oxide ions and depends on not being a stable material due to strong stress generated during electrolysis. Some metals are difficult to electroplat, such as titanium, aluminum, molybdenum, and tungsten. These are due to the fact that a single metal, which is highly oxidizable, cannot exist as ions in an aqueous solution. In electroformed alloys, stress during electrolysis often becomes a problem, and in recent technologies, it is becoming possible to realize low stress in the electrolyte by the advent of various water-soluble metal compounds.
- the alloy is immersed in a sanitizing solution, a solution of PH 3.0 to 8.0, a disinfecting solution such as Milton (registered trademark), and then accelerated dissolution in the test solution.
- a sanitizing solution a solution of PH 3.0 to 8.0, a disinfecting solution such as Milton (registered trademark)
- the sample was forced to vibrate at 100 kHz, and then a metal ion elution test was conducted.
- the analysis of the solution is atomic absorption analysis, and the analysis limit value is PPB.
- the composition in which metal ions did not elute was as follows. 1) Gold and palladium alloys have no metal ion elution at any composition.
- Gold and any alloy of silver, nickel, and cobalt have no metal ion elution when the gold content is 65% or more.
- Palladium and any alloy of gold, silver, copper, nickel, and cobalt have no elution of metal ions when the content of paradium is 60% or more.
- the alloy of the stent element 2 30% gold and 70% palladium alloy, 90% gold and 10% silver alloy, 35% cobalt and 65% palladium alloy, 80% gold, 15% silver and 15% cobalt. % Of alloy, alloy selected from 80% gold, 15% palladium, 5% cobalt alloy, and electrocasting, the results of proof stress (elastic limit stress) and fatigue strength are the same as above. It was confirmed that it was obtained.
- all of the stents 1 made with these compositions show excellent X-ray absorbability equivalent to or better than conventional stents made of stainless steel, cobalt, chromium, etc., and have excellent practical performance. In terms of corrosion resistance, sufficient performance was exhibited.
- the stent 1 of the present invention has a homogeneous composition, is non-magnetic, and has excellent artifacts with respect to images by diagnostic equipment using a high magnetic field such as MRI, which has been generalized in recent years, as compared with conventional products.
- stents for the purpose of preventing restenosis of tubular tissues such as blood vessels and digestive organs after stent placement, 1.
- the metal surface of the stent is coated with a component having relatively good antithrombogenic properties such as PC (pyrolite carbon) and DLC (diamond-like carbon).
- PC pyrolite carbon
- DLC diamond-like carbon
- a polymer is coated on the metal surface of the stent, and the polymer is surface-modified with an antithrombotic material.
- this polymer contains a drug that suppresses tissue growth, and the drug is released slowly from this polymer. 4.
- the polymer After coating the metal surface of the stent with a biodegradable polymer, the polymer is allowed to contain a drug that suppresses tissue growth, the polymer is gradually degraded, and the drug is completely released in a certain period of time. 5.
- a small dimple (irregularity) is made on the stent surface, and a drug is contained therein to give a tissue growth preventing effect for a relatively short period of time. In the stent 1 of the present invention, these can be easily applied.
- the main stent element for tubular organ expansion is used to prevent enlargement of cancerous tissue and restenosis of the tubular organ.
- stents made of secondary stent elements to increase the cell density of the stent and suppress tissue overhang, etc. it is possible to provide a material with excellent strength. A material having excellent strength can be easily realized.
- a stent placed in a branch blood vessel is used to secure a blood flow in the branch blood vessel and facilitate the approach of devices such as catheters and stents.
- any of these can be easily applied.
- the stent 1 has a proof stress of the main stent element 2 of 500 to 2,700 MPa, so that it expands easily and uniformly in the radial direction. It was confirmed that was not easily crushed in the radial direction.
- the cell diameter of the main stent element 2 is 10 to 30 ⁇ m and the diameter of the connecting portion is 5 to 9 ⁇ m, even if the stent 1 is placed in the blood vessel, the stent 1 interferes with blood flow and blood It was also confirmed that the flow did not worsen. Further, it was confirmed that when the blood vessel meanders so as to wave, the thin connecting portion also follows and bends, and the cell 2 is firmly supported from the inside of the blood vessel in close contact with the inner wall of the blood vessel.
Landscapes
- Health & Medical Sciences (AREA)
- Engineering & Computer Science (AREA)
- Biomedical Technology (AREA)
- Life Sciences & Earth Sciences (AREA)
- Veterinary Medicine (AREA)
- Public Health (AREA)
- General Health & Medical Sciences (AREA)
- Animal Behavior & Ethology (AREA)
- Heart & Thoracic Surgery (AREA)
- Vascular Medicine (AREA)
- Cardiology (AREA)
- Transplantation (AREA)
- Oral & Maxillofacial Surgery (AREA)
- Physics & Mathematics (AREA)
- Optics & Photonics (AREA)
- Chemical & Material Sciences (AREA)
- Inorganic Chemistry (AREA)
- Surgery (AREA)
- Epidemiology (AREA)
- Media Introduction/Drainage Providing Device (AREA)
- Materials For Medical Uses (AREA)
- Prostheses (AREA)
Abstract
Description
このように、ステント要素の耐力の下限値が、特許文献1に記載のステントの300MPaよりも大きい500MPaで、しかも上限値が2,700MPaであるため、極めて薄い肉厚のステントでも外圧に耐えることができるようになり血管内にステントを配置した時に血管断面積を犠牲にすることが無くなるとともに、半径方向に容易に且つ均一に拡張でき、且つ拡張後には半径方向に容易に潰れないようにしたものである。
このように、従来、電鋳によってニッケルまたはニッケル/コバルト合金で作製されていたステントよりも高い疲労強度を持たせるようにしたもので、好ましくは1.5倍以上の疲労強度を持たせるようにしたものである。
このように、疲労強度が極めて高い材料を電鋳で作ることができたため、特に振動を常時加えられる部位のステントには最適であり、しかも、半径方向に容易に且つ均一に拡張でき、且つ拡張後には半径方向に容易に潰れないようにしたものである。
このように、選定された化合物を添加剤として用いることにより、耐力及び疲労強度が高いステントを作成したものである。
このように、耐力を大幅に改善させることで疲労強度の向上が図られる合金を選んで電鋳で作製することにより、特許文献2に記載のステントの上述した課題を解決したものである。
このように、ステントを平面形状で作製した後、筒形状に丸めて接合部を電気抵抗溶接やレーザー溶接などで接合することにより、生産性と品質性を向上させるようにしたものである。
このように、電着の方法を用いたので、接合の時に熱が全くかからないため、熱による焼きなましや、熱変形による脆さなどが生じることはなく、また接合部は素材と同じ光沢を保持できるため外観は滑らかであり、ステントを生体の管腔内に挿入する時には好都合である。
このように、セルの線径、即ち、ステントの肉厚を10~50μmとすることにより、特許文献1に記載のステントの肉厚60μmよりも薄くしたので、ステントを血管内に留置してもステントが血流の邪魔をして血流が悪くなることはなく、しかも連結部の線径を5~20μmと細くしたので、血管が波を打つように蛇行すると、連結部も屈曲してセルが血管の内壁を内側から確実に支持するようにしたものである。
また、この実施形態では、ステント1を図2に示すように平面で作っておき、これを図1に示すように円筒状に丸めて、電着で円筒にしているが、初期から円筒状のマンドレルにレジストをコーティングした後、円筒状に露光してエッティングを行うことにより、ステント1を作製しても良い。
次に、この複数のセル3をマスキングした状態で、再び、基板上にレジストをコートしてフォトマスクを置いた後、紫外線を当てて露光して除去し、この除去した部分に上述した合金を電鋳で2回目の析出を行い、連結部4を作製する。このとき、セル3と連結部4は互いに一部が連結するよう露光され、その後、電着するので、結果として連結体となる。このようにして、複数のセル3と連結部4とが上述した合金で一体に成形され、主ステント要素2が図2に示すように作製される。
このように、厚さや幅を自由に正確に制御することができることはステント1に今までに無い高い機能を付与させることが可能になり、これは従来のレーザーなどで加工したステントでは全く得ることができない大きな特徴である。
この接合方法によれば、接合の時に熱が全くかからないため、熱による焼きなましや、熱変形による脆さなどが生じることはなく、また接合部5A、5Bは素材と同じ光沢を保持できるため外観は滑らかであり、ステント1を血管などの体腔内に挿入する時には好都合である。
その結果、金属イオンが溶出しない組成は以下のようであった。
1)金とパラジュームの合金は、どのような組成でも金属のイオン溶出は全く無い。
2)金と、銀、ニッケル、コバルトのいずれかの合金は、金の含有率が65%以上では金属イオン溶出は全く無い。
3)パラジュームと、金、銀、銅、ニッケル、コバルトのいずれかの合金は、パラジュームの含有率が60%以上では金属イオンの溶出は全く無い。
尚、これらの組成で作成されたステント1は、いずれも、ステンレスやコバルト、クロムなど、従来の材料で作成されたステントに比べ、同等以上の優れたX線吸収性を示し、実用性能に優れ、耐食性に関しても、十分な性能を示した。
また、本発明のステント1は、均質な組成からなっており、非磁性であり、近年一般化した、MRIなど、高磁場を用いた診断機器による画像に対するアーティファクトも従来品に比べ優れている。
1、ステントの金属表面に、PC(パイロライトカーボン)、DLC(ダイヤモンドライクカーボン)など、比較的抗血栓性が良いとされる成分をコーティングする。
2、ステントの金属表面にポリマーをコーティングして、このポリマーを抗血栓性材料で表面修飾する。
3、ステントの金属表面にポリマーをコーティングした後、このポリマーに組織増殖を抑制する薬剤を含ませ、このポリマーから薬剤を徐放させる。
4、ステントの金属表面に生分解性ポリマーをコーティングした後、このポリマーに組織増殖を抑制する薬剤を含ませ、このポリマーを徐々に分解させ、薬剤を一定期間で完全に放出させる。
5、ステント表面に小さなディンプル(凹凸)を作り、ここに薬剤を含ませ、比較的短期間だけ、組織増殖防止効果を持たせる。
ことなどが行われているが、本発明のステント1では、これらを容易に適用できる。
1、分岐血管に留置するステント(Y-ステント)で、分岐血管への血流の確保、カテーテル、ステントなどのデバイスのアプローチを容易にするため、円筒状のステントの一部のセルを大きく開口させる。
2、或いは、ステントの長さ方向の剛性を調整し、曲げ方向が柔軟で、挿入しやすい構造のステントとするため、主ステント要素に比べ、副ステント要素のステント長さ方向のステント連結要素などを細く作る。
など、特殊なデザインが用いられるが、本発明では、これらはいずれも容易に適用できる。
本実施形態は上記のように構成されており、以下その作用について説明する。バルーンカテーテルのバルーン部を収縮させた状態で、このバルーン部の外側に図1に示すステント1を縮径状態で装着する。そして、ステント1をバルーン部と一緒に血管内に挿入して、血管内の狭窄部にバルーン部を位置させ、バルーン部を膨らませるとステント1も膨らみ、拡張してステント1は拡張状態を維持したまま留置され、バルーンカテーテルのみが引き抜かれる。
また、主ステント要素2のセルの線径が10~30μm、連結部の線径が5~9μmであるため、ステント1を血管内に留置してもステント1が血流の邪魔をして血流が悪くなることもないことも確認できた。更に血管が波を打つように蛇行すると、細い連結部も追従して屈曲してセル2が血管の内壁に密着した状態で血管の内側から確実に支持することも確認できた。
1 ステント
2 主ステント要素
3 セル
4 連結部
Claims (10)
- 生体の管腔内に留置される半径方向に拡張可能な筒形状のステントであって、円筒仮想表面に形成された主ステント要素から成り、この主ステント要素は耐力が500~2,700MPaの合金から作製されたことを特徴とするステント。
- 生体の管腔内に留置される半径方向に拡張可能な筒形状のステントであって、円筒仮想表面に形成された主ステント要素から成り、この主ステント要素はニッケルまたはニッケル/コバルト合金より高い疲労強度を有する合金から作製されたことを特徴とするステント。
- 前記主ステント要素の疲労強度は、前記ニッケルまたはニッケル/コバルト合金の1.5倍以上の強度を有する合金である請求項2に記載のステント。
- 前記主ステント要素は、金、銀、銅、ニッケル、コバルト、パラジュームのいずれかを含む電鋳合金である請求項1~請求項3のいずれか1項に記載のステント。
- 前記主ステント要素は、硫酸塩、塩化物、アンモニア錯塩、シアン錯塩、アミン錯塩、スルファミン塩、次亜りん酸塩、ピロリン酸塩、酒石酸塩、EDTAのいずれかの化合物を添加して、金、銀、銅、ニッケル、コバルト、パラジュームのいずれかを含む合金を用いて電鋳で作製されている請求項4に記載のステント。
- 前記主ステント要素は、金を主構成成分とし、銀、銅、ニッケル、コバルト、パラジュームから選ばれた少なくとも1つ以上の合金を用いて、電鋳で作製されている請求項4または請求項5に記載のステント。
- 前記主ステント要素は、パラジュームを主構成成分とし、金、銀、銅、ニッケル、コバルトから選ばれた少なくとも1つ以上の合金を用いて、電鋳で作製されている請求項4または請求項5に記載のステント。
- 前記主ステント要素は、筒形状に形成するための接合部を有している請求項1~請求項7のいずれか1項に記載のステント。
- 前記主ステント要素は、前記接合部が電着により接合される請求項8に記載のステント。
- 前記主ステント要素は、複数のセルとこのセル同士を連結する連結部からなり、セルの線径が10~50μm、連結部の線径が5~20μmである請求項1~請求項9のいずれか1項に記載のステント。
Priority Applications (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
KR1020137006067A KR101597405B1 (ko) | 2010-08-12 | 2011-08-10 | 스텐트 |
CN2011800393607A CN103079605A (zh) | 2010-08-12 | 2011-08-10 | 支架 |
US13/814,939 US20130138204A1 (en) | 2010-08-12 | 2011-08-10 | Stent |
EP11816476.3A EP2604228A4 (en) | 2010-08-12 | 2011-08-10 | STENT |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2010181172A JP5713336B2 (ja) | 2010-08-12 | 2010-08-12 | ステント |
JP2010-181172 | 2010-08-12 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2012020812A1 true WO2012020812A1 (ja) | 2012-02-16 |
Family
ID=45567773
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/JP2011/068314 WO2012020812A1 (ja) | 2010-08-12 | 2011-08-10 | ステント |
Country Status (6)
Country | Link |
---|---|
US (1) | US20130138204A1 (ja) |
EP (1) | EP2604228A4 (ja) |
JP (1) | JP5713336B2 (ja) |
KR (1) | KR101597405B1 (ja) |
CN (1) | CN103079605A (ja) |
WO (1) | WO2012020812A1 (ja) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN102605390A (zh) * | 2012-03-31 | 2012-07-25 | 大连理工大学 | 电铸制备血管支架用可降解Fe-Zn合金管材的方法 |
Families Citing this family (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP6175283B2 (ja) * | 2013-06-03 | 2017-08-02 | 東邦金属株式会社 | ステント |
CN105848611B (zh) * | 2013-12-24 | 2019-01-29 | 尼普洛株式会社 | 支架 |
CN107427354A (zh) | 2015-03-30 | 2017-12-01 | C·R·巴德股份有限公司 | 向医疗装置施加抗微生物剂 |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2000008187A (ja) | 1998-06-25 | 2000-01-11 | Oudenshiya:Kk | ステントおよびその製造方法 |
JP2006175211A (ja) * | 2004-11-09 | 2006-07-06 | Cordis Corp | 脈管内医療器具用の疲労に対する耐性を有するコバルト・クロム・モリブデン合金 |
JP2007267844A (ja) | 2006-03-30 | 2007-10-18 | Terumo Corp | 生体器官拡張用ステントおよびその製造方法 |
JP2008539898A (ja) * | 2005-05-05 | 2008-11-20 | ボストン サイエンティフィック リミテッド | 医療用具およびその製造方法 |
WO2009041691A1 (ja) * | 2007-09-28 | 2009-04-02 | Terumo Kabushiki Kaisha | 生体内留置物 |
Family Cites Families (11)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5024733A (en) * | 1989-08-29 | 1991-06-18 | At&T Bell Laboratories | Palladium alloy electroplating process |
US6019784A (en) * | 1996-04-04 | 2000-02-01 | Electroformed Stents, Inc. | Process for making electroformed stents |
US5906759A (en) * | 1996-12-26 | 1999-05-25 | Medinol Ltd. | Stent forming apparatus with stent deforming blades |
WO1999065623A1 (en) * | 1998-06-15 | 1999-12-23 | Scimed Life Systems, Inc. | Process of making composite stents with gold alloy cores |
US6506211B1 (en) * | 2000-11-13 | 2003-01-14 | Scimed Life Systems, Inc. | Stent designs |
US20030044307A1 (en) * | 2001-08-27 | 2003-03-06 | Crombie Edwin Alfred | Palladium/platinum alloy |
CA2525094C (en) * | 2003-05-07 | 2013-04-09 | Advanced Bio Prosthetic Surfaces, Ltd. | Metallic implantable grafts and method of making same |
US20050090888A1 (en) * | 2003-10-28 | 2005-04-28 | Hines Richard A. | Pleated stent assembly |
US7901451B2 (en) * | 2004-09-24 | 2011-03-08 | Biosensors International Group, Ltd. | Drug-delivery endovascular stent and method for treating restenosis |
CN100358482C (zh) * | 2005-01-31 | 2008-01-02 | 武汉理工大学 | 多功能医用金属支架及制备方法 |
WO2010033873A1 (en) * | 2008-09-19 | 2010-03-25 | Fort Wayne Metals Research Products Corporation | Fatigue damage resistant wire and method of production thereof |
-
2010
- 2010-08-12 JP JP2010181172A patent/JP5713336B2/ja not_active Expired - Fee Related
-
2011
- 2011-08-10 US US13/814,939 patent/US20130138204A1/en not_active Abandoned
- 2011-08-10 KR KR1020137006067A patent/KR101597405B1/ko not_active IP Right Cessation
- 2011-08-10 WO PCT/JP2011/068314 patent/WO2012020812A1/ja active Application Filing
- 2011-08-10 CN CN2011800393607A patent/CN103079605A/zh active Pending
- 2011-08-10 EP EP11816476.3A patent/EP2604228A4/en not_active Withdrawn
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2000008187A (ja) | 1998-06-25 | 2000-01-11 | Oudenshiya:Kk | ステントおよびその製造方法 |
JP2006175211A (ja) * | 2004-11-09 | 2006-07-06 | Cordis Corp | 脈管内医療器具用の疲労に対する耐性を有するコバルト・クロム・モリブデン合金 |
JP2008539898A (ja) * | 2005-05-05 | 2008-11-20 | ボストン サイエンティフィック リミテッド | 医療用具およびその製造方法 |
JP2007267844A (ja) | 2006-03-30 | 2007-10-18 | Terumo Corp | 生体器官拡張用ステントおよびその製造方法 |
WO2009041691A1 (ja) * | 2007-09-28 | 2009-04-02 | Terumo Kabushiki Kaisha | 生体内留置物 |
Non-Patent Citations (1)
Title |
---|
See also references of EP2604228A4 |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN102605390A (zh) * | 2012-03-31 | 2012-07-25 | 大连理工大学 | 电铸制备血管支架用可降解Fe-Zn合金管材的方法 |
Also Published As
Publication number | Publication date |
---|---|
JP5713336B2 (ja) | 2015-05-07 |
EP2604228A4 (en) | 2014-01-22 |
KR101597405B1 (ko) | 2016-02-24 |
JP2012040050A (ja) | 2012-03-01 |
CN103079605A (zh) | 2013-05-01 |
EP2604228A1 (en) | 2013-06-19 |
KR20130138195A (ko) | 2013-12-18 |
US20130138204A1 (en) | 2013-05-30 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US8273117B2 (en) | Low texture, quasi-isotropic metallic stent | |
WO2012020812A1 (ja) | ステント | |
JP4871692B2 (ja) | 生体内留置用ステントおよび生体器官拡張器具 | |
JP5481645B2 (ja) | 強化リング | |
JP5078271B2 (ja) | 生体器官拡張用ステントおよびその製造方法 | |
JP2017000729A (ja) | 複数相鉄鋼を含むエンドプロテーゼ | |
Mohammadi et al. | Inductive antenna stent: design, fabrication and characterization | |
Haga et al. | Development of minimally invasive medical tools using laser processing on cylindrical substrates | |
WO2002005863A1 (en) | Radiopaque stent composed of a binary alloy | |
EP3583925B1 (en) | Stent | |
US20060130934A1 (en) | Medical instrument for soft tissue and method for manufacture thereof | |
JP3323132B2 (ja) | ステントおよびその製造方法 | |
JP6628263B2 (ja) | 生体吸収性ステント | |
JP3145720U (ja) | ステント | |
JP2001238964A (ja) | ステント | |
JP3146103U (ja) | ステント | |
JP4654361B2 (ja) | ステント | |
JP2006247140A (ja) | ステントの製造方法及びステント | |
JP6380909B2 (ja) | ステント | |
JP5401148B2 (ja) | 生体内留置用ステントおよび生体器官拡張器具 | |
JP2008036076A (ja) | バルーン拡張型ステントおよびその製造方法 | |
CN112656543B (zh) | 迁移能力降低的外周血管支架 | |
US8597872B2 (en) | Method for production of a medical marker | |
JP2009142664A (ja) | 生体軟組織用医療用具とその製造方法 | |
JP3754052B2 (ja) | 生体内留置用ステント |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
WWE | Wipo information: entry into national phase |
Ref document number: 201180039360.7 Country of ref document: CN |
|
121 | Ep: the epo has been informed by wipo that ep was designated in this application |
Ref document number: 11816476 Country of ref document: EP Kind code of ref document: A1 |
|
DPE2 | Request for preliminary examination filed before expiration of 19th month from priority date (pct application filed from 20040101) | ||
WWE | Wipo information: entry into national phase |
Ref document number: 13814939 Country of ref document: US |
|
NENP | Non-entry into the national phase |
Ref country code: DE |
|
REEP | Request for entry into the european phase |
Ref document number: 2011816476 Country of ref document: EP |
|
WWE | Wipo information: entry into national phase |
Ref document number: 2011816476 Country of ref document: EP |
|
ENP | Entry into the national phase |
Ref document number: 20137006067 Country of ref document: KR Kind code of ref document: A |