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WO2001091669A2 - Stent - Google Patents

Stent Download PDF

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Publication number
WO2001091669A2
WO2001091669A2 PCT/DE2001/002106 DE0102106W WO0191669A2 WO 2001091669 A2 WO2001091669 A2 WO 2001091669A2 DE 0102106 W DE0102106 W DE 0102106W WO 0191669 A2 WO0191669 A2 WO 0191669A2
Authority
WO
WIPO (PCT)
Prior art keywords
stent
sections
stent according
state
legs
Prior art date
Application number
PCT/DE2001/002106
Other languages
German (de)
English (en)
Other versions
WO2001091669A3 (fr
Inventor
Heinz Oberle
Dieter Poeschkens
Johannes Jung
Original Assignee
Caremed Medical Produkte Ag
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Caremed Medical Produkte Ag filed Critical Caremed Medical Produkte Ag
Priority to AU2001277454A priority Critical patent/AU2001277454A1/en
Priority to EP01955193A priority patent/EP1370196A2/fr
Publication of WO2001091669A2 publication Critical patent/WO2001091669A2/fr
Publication of WO2001091669A3 publication Critical patent/WO2001091669A3/fr

Links

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
    • 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
    • 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
    • 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
    • A61F2/848—Devices providing patency to, or preventing collapsing of, tubular structures of the body, e.g. stents having means for fixation to the vessel wall, e.g. barbs
    • 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
    • A61F2002/91533—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 characterised by the phase between adjacent bands

Definitions

  • the present invention relates to a stent.
  • Stents are implants that are implanted in hollow organs, such as ureters, biliary tract, but above all blood vessels, if these are no longer sufficiently stable due to pathological changes or if they are sufficiently permeable to the required fluid flow, for example blood flow, due to deposits such as calcifications and are therefore dilated Need to become.
  • An implanted stent should be able to follow natural body movements well, which requires a sufficiently high degree of flexibility. It must support the vessel against the external forces, ie it must be sufficiently stable in the radial direction his. It should not move away from the intended location during or after implantation, which is also referred to as "laying", and it should be easy to lay. This implies that it is axially shortened as little as possible during radial expansion it is important to be able to determine its exact position in the hollow vessel well.
  • stent In order to place the stent, it is typically pushed with a balloon catheter in a contracted state to the intended location and expanded there. The expansion takes place in that the balloon catheter is inflated to a radial dimension sufficient for the stent expansion at the pathologically changed location.
  • self-expanding stents can be used which are produced from a material with shape memory, for example a so-called memory metal such as Nitinol.
  • the stent for implantation in a body lumen such as an artery is known from US Pat. No. 5,514,154.
  • the stent consists of a large number of radially expandable, cylindrical elements, which are arranged on a common axis. mine aligned and connected by one or more connecting elements.
  • the individual, radially expandable cylindrical elements are made of band-like material, which is arranged in a wavy pattern. Portions of the expanded stent engage the outside of the vessel wall to secure the stent to the vessel.
  • the connecting, elongated elements, which the expandable cylindrical elements should have a cross-section that is similar to the transverse dimensions of the wave-like components of the expandable stent.
  • all connecting elements of a stent should attach to either the peaks or valleys of the undulating structure of the cylindrical elements. It is mentioned that otherwise a stent shortening can be expected during its expansion.
  • the aim of the present invention is to provide a novel stent for commercial use.
  • the aim of this invention is achieved with a stent according to independent claim 1.
  • Preferred embodiments can be found in the subclaims.
  • a stent 'a first state with low internal diameter to a second state which is made expandable, in which the internal width is enlarged and material-free areas together with Mate rial webs define a- general stent sheath surface, via which Material webs protrude in sections in the expanded state, it being provided that a first group of sections is intended to protrude over the stent jacket surface in the direction of flow in the implanted state and a second group of sections is provided in the implant protruded state in the counterflow direction over the stent jacket surface.
  • a first essential aspect of the invention is thus seen in the fact that a stent jacket surface is provided, over which sections of material webs protrude in opposite directions. This ensures good vascular stabilization through the general stent jacket surface and fixation in the axial vascular direction due to the protruding sections. In this way it is possible to optimally place radially fixed and axially stable expanding stents. It was recognized that the axial stability during positioning increases if fixation takes place via material webs projecting in opposite directions, without a shortening Positioning endangered.
  • the material webs which protrude over the general stent jacket surface during expansion, can be grouped in the axial direction, for example in the stent generally circular circumferential groups.
  • the connection between such groups is preferably established via material webs which have a substantially larger cross-section, in particular a larger, preferably approximately twice the width, as the material webs ' within the group which encircles the stent cylindrically.
  • the material webs can bifurcate at the axial height of the groups encircling the stent, one partial fork being guided to the next group in the axial direction and the other partial fork leading to a material section in the axial group which, in the case of stent expansion, takes place via the general stent man- telflache protrudes.
  • the continuous structure through the bifurcation contributes to a slight stent shortening, typically only in the percentage range.
  • a partial fork coming from below is connected to a partial fork coming from above, with a particularly small expansion reduction and high radial stability, an alternating change in the flow and counterflow direction via the general one Stent jacket flat protruding areas achieved, which improves the anchorage, especially if the material sections that lead into the groups surrounding the stent are connected via rounded, widened tips. It is advantageous here that a large number of compounds are present.
  • groups of both orientations are thus provided in this way, preferably alternately side by side.
  • a high radial compressive strength is achieved if the sections for one direction are arranged on a generally axially extending line, while the sections alternate radially for the opposite directions.
  • the alternating change in the radial direction leads to a general zigzag pattern of the sections over the expanded stent, with these repeating in the axial direction.
  • the zigzag areas encircling the stent circumference are preferably connected by sections inclined to the axial direction, which further increases the stability and at the same time ensures good flexibility.
  • the stent of the present invention will be typically formed integrally ⁇ , in particular of metal, although it may be as known in the art per se, cut from a one-piece metal tube; cutting can be done with lasers or other suitable, high-precision controllable cutting tools respectively. Cutting in the sense of the invention is understood to mean any suitable method for producing the structures according to the invention.
  • the stent can be made of stainless steel or a nickel-titanium, in particular nitinol, or another memory alloy. In all cases it is preferred to electroplate or otherwise refine the surface in order to ensure a sufficiently smooth and body-compatible surface.
  • the stent jacket surface will be generally cylindrical, wherein the stent can have a radial protuberance at one or both axial ends.
  • the sections can each be formed by two interconnected legs or parts thereof, the two legs preferably being arranged at least approximately and essentially parallel to one another in a non-expanded or only slightly expanded state and being able to be spread out like scissors by the expansion , so that they assume an acute angle to one another when the stent is expanded.
  • the legs are connected to one another by an enlarged tip, which is preferably rounded on the side facing away from the legs.
  • the arrangement with two legs, which are generally parallel to one another in the unexpanded state and spread apart in the expanded state leads to the bending of the rounded tip beyond the stent jacket surface due to the mechanical stresses during the expansion, similar to a divining rod.
  • the tips preferably lead to the material webs connecting circumferential groups to the bifurcations described above. It is particularly preferred if the stent has less than 5%, preferably less than 2% contraction upon expansion. This ensures that the sections serving as general barbs do not move along the vessel wall in a hurtful manner during expansion.
  • Fig.l is a photograph of the expanded stent striped over a non-transparent cylinder according to the present invention
  • Fig. 2 is a schematic 'enlargement of the photo of Fig. 1.
  • Fig. 3 shows the developed pattern of a stent according to the present invention.
  • a stent 1 in its expanded state with a clear width that is larger than that in the non-expanded state, comprises an approximately cylindrical stent jacket surface 2, which is defined in its overall course by the material-free regions 3 and the material webs 4 surrounding them ,
  • the material webs now have sections 5 which project beyond the stent jacket surface 2. This can be seen particularly well for those sections 5 which are viewed approximately from the side and which are therefore on the edge when viewed from above. It will be appreciated that with the uniform geometry, the slots 5b pointing in the other direction will also protrude.
  • the stent 1 is cut from the memory alloy Nitinol, starting with a one-piece metal tube continuous wall.
  • the developed wall pattern is shown in Fig. 3.
  • FIG. 3 shows that the sections 5a and 5b, which protrude beyond the stent jacket surface during expansion, are formed by parallel legs 6a, 6b in the unexpanded state, which are formed by an arc 7 which is wider than the width of the Legs 6a, 6b are connected.
  • the tips pointing radially alternately in the direction of flow and counterflow when the stent is placed form meandering sections around the circumference.
  • meandering sections are axially connected to one another by the connecting webs 4, the connecting webs 4 being at an alternating angle to the stent axis and bifurcating on the meandering sections as shown, a first partial fork leading into the peripheral group and forming a leg 6a, 6b and the other partial fork is axially continued by the circumferential group.
  • the stent is manufactured and used as follows:
  • a suitably dimensioned output tube of memory metal in accordance with the unwound 'shown pattern of FIG. Cut. 3
  • the expanded metal stent is then impressed into the memory metal in a known manner and the stent is then cooled so that it contracts to the small tube diameter, is placed on a catheter in the cold state and is pushed to the pathological vascular site with a suitable setting device. There the stent is released from the setting device, heated and expanded, whereupon its stent jacket surface lies against the vessel wall.
  • the legs 6a, 6b are pulled apart at an acute angle, whereupon the rounded tips zen 7 can be opened over the stent jacket surface. The radial expansion takes place with minimal contraction.
  • the protruding sections 5a, 5b and thus in particular the rounded tips 7 can get caught on the intima of the vascular wall intima without injuring them.
  • the sections in the flow direction and counter-flow direction that protrude after expansion ensure that movement is possible both in the flow direction and in the counter-flow direction.
  • the expanded stent is therefore firmly seated in the vessel, even before it has grown in.
  • the stent of the present invention is able to absorb high radial forces, is secure against wandering and, to facilitate storage, can be twisted in itself.

Landscapes

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

Abstract

L'invention concerne un stent expansible, pouvant passer d'un premier état, dans lequel il présente un faible diamètre intérieur, à un deuxième état, dans lequel son diamètre intérieur est plus important et dans lequel des zones exemptes de matière sont adjacentes à des nervures de façon à définir avec ces dernières une enveloppe de stent globale par rapport à laquelle des nervures font saillie sur certains segments lorsque le stent se trouve dans le deuxième état. Lorsque le stent est implanté, un premier groupe de segments fait saillie par rapport à l'enveloppe de stent dans le sens d'écoulement et un deuxième groupe de segments fait saillie par rapport à l'enveloppe de stent dans le sens inverse au sens d'écoulement.
PCT/DE2001/002106 2000-05-31 2001-05-31 Stent WO2001091669A2 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
AU2001277454A AU2001277454A1 (en) 2000-05-31 2001-05-31 Stent
EP01955193A EP1370196A2 (fr) 2000-05-31 2001-05-31 Stent

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE2000126871 DE10026871A1 (de) 2000-05-31 2000-05-31 Stent
DE10026871.4 2000-05-31

Publications (2)

Publication Number Publication Date
WO2001091669A2 true WO2001091669A2 (fr) 2001-12-06
WO2001091669A3 WO2001091669A3 (fr) 2003-10-09

Family

ID=7644156

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/DE2001/002106 WO2001091669A2 (fr) 2000-05-31 2001-05-31 Stent

Country Status (4)

Country Link
EP (1) EP1370196A2 (fr)
AU (1) AU2001277454A1 (fr)
DE (1) DE10026871A1 (fr)
WO (1) WO2001091669A2 (fr)

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0541443A1 (fr) 1991-11-08 1993-05-12 Meadox Medicals, Inc. Endoprothèse pour implantation transluminale
EP0647438A1 (fr) 1993-10-07 1995-04-12 Angiomed Ag Stent à réduction, dispositif avec ce stent et utilisation de ce stent
WO1995026695A2 (fr) 1994-04-01 1995-10-12 Prograft Medical, Inc. Extenseur et greffe a extenseur autodeployables et leur mode d'utilisation
EP0709068A2 (fr) 1994-10-27 1996-05-01 Medinol Ltd. Extenseur radioopaque
EP0709067A2 (fr) 1994-10-27 1996-05-01 Medinol Limited Procédé de fabrication d'un extenseur
US5514154A (en) 1991-10-28 1996-05-07 Advanced Cardiovascular Systems, Inc. Expandable stents
EP0800800B1 (fr) 1996-04-10 1998-07-15 Variomed AG Stent pour implantation transluminale dans un organe creux

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4418336A1 (de) * 1994-05-26 1995-11-30 Angiomed Ag Stent
FR2728156B1 (fr) * 1994-12-16 1997-05-30 Fouere Alain Manchon extensible interne a usage chirurgical pour dilatation de conduits physiologiques
DE19746882A1 (de) * 1997-10-23 1999-04-29 Angiomed Ag Aufgeweiteter Stent und Verfahren zum Herstellen desselben

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5514154A (en) 1991-10-28 1996-05-07 Advanced Cardiovascular Systems, Inc. Expandable stents
EP0541443A1 (fr) 1991-11-08 1993-05-12 Meadox Medicals, Inc. Endoprothèse pour implantation transluminale
EP0647438A1 (fr) 1993-10-07 1995-04-12 Angiomed Ag Stent à réduction, dispositif avec ce stent et utilisation de ce stent
WO1995026695A2 (fr) 1994-04-01 1995-10-12 Prograft Medical, Inc. Extenseur et greffe a extenseur autodeployables et leur mode d'utilisation
EP0709068A2 (fr) 1994-10-27 1996-05-01 Medinol Ltd. Extenseur radioopaque
EP0709067A2 (fr) 1994-10-27 1996-05-01 Medinol Limited Procédé de fabrication d'un extenseur
EP0800800B1 (fr) 1996-04-10 1998-07-15 Variomed AG Stent pour implantation transluminale dans un organe creux

Also Published As

Publication number Publication date
WO2001091669A3 (fr) 2003-10-09
EP1370196A2 (fr) 2003-12-17
DE10026871A1 (de) 2002-02-28
AU2001277454A1 (en) 2001-12-11

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