Procedures for introducing stents and stent-grafts

• US 5,873,906 A
• Filed: 07/21/1997
• Issued: 02/23/1999
• Est. Priority Date: 09/08/1994
• Status: Expired due to Term

• Current Assignee: W. L. Gore & Associates (W.L. Gore & Associates)
• Original Assignee: Gore Enterprise Holdings Incorporated (W.L. Gore and Associates)
• Inventors: Maroney, Charles T., Lau, Lilip, Hartigan, William M., Lam, Sharon
• Primary Examiner(s): Prebilic, Paul B.
• Application Number:
  US08/897,615
• Time in Patent Office: 582 Days
• Field of Search: 623/1, 623/11, 623/66, 606/198, 128/898, 604/107, 604/109
• US Class Current: 128/898
• CPC Class Codes: A61F 2/07 Stent-grafts
• CPC Class Codes: A61F 2/844 folded prior to deployment
• CPC Class Codes: A61F 2/88 the wire-like elements formed as helical or spiral coils forming a net-like or mesh-like structure A61F2/90
• CPC Class Codes: A61F 2/89 the wire-like elements comprising two or more adjacent rings flexibly connected by separate members
• CPC Class Codes: A61F 2/91 made from perforated sheet material or tubes, e.g. perforated by laser cuts or etched holes
• CPC Class Codes: A61F 2/915 with bands having a meander structure, adjacent bands being connected to each other
• CPC Class Codes: A61F 2/92 Stents in the form of a rolled-up sheet expanding after insertion into the vessel , e.g. with a spiral shape in cross-section
• CPC Class Codes: A61F 2/95 Instruments specially adapted for placement or removal of stents or stent-grafts
• CPC Class Codes: A61F 2002/061 provided with means for allowing access to secondary lumens
• CPC Class Codes: A61F 2002/072 Encapsulated stents, e.g. wire or whole stent embedded in lining
• CPC Class Codes: A61F 2002/075 the stent being loosely attached to the graft material, e.g. by stitching
• CPC Class Codes: A61F 2002/3008 radio-opaque, e.g. radio-opaque markers
• CPC Class Codes: A61F 2002/30092 using shape memory or superelastic materials, e.g. nitinol
• CPC Class Codes: A61F 2002/30462 retained or tied with a rope, string, thread, wire or cable
• CPC Class Codes: A61F 2002/828 Means for connecting a plurality of stents allowing flexibility of the whole structure
• CPC Class Codes: A61F 2002/91508 the meander having a difference in amplitude along the band
• CPC Class Codes: A61F 2002/91516 the meander having a change in frequency along the band
• CPC Class Codes: A61F 2002/91533 characterised by the phase between adjacent bands
• CPC Class Codes: A61F 2002/91558 connected peak to peak
• CPC Class Codes: A61F 2002/91575 connected peak to trough
• CPC Class Codes: A61F 2002/9511 : the retaining means being filaments or wires
• CPC Class Codes: A61F 2002/9665 : with additional retaining means
• CPC Class Codes: A61F 2210/0019 : operated at only one temperature whilst inside or touching the human body, e.g. constrained in a non-operative shape during surgery, another temperature only occurring before the operation
• CPC Class Codes: A61F 2220/0075 : sutured, ligatured or stitched, retained or tied with a rope, string, thread, wire or cable
• CPC Class Codes: A61F 2230/0039 : H-shaped
• CPC Class Codes: A61F 2230/0041 : J-shaped
• CPC Class Codes: A61F 2230/006 : Y-shaped
• CPC Class Codes: A61F 2230/0078 : hyperboloidal
• CPC Class Codes: A61F 2250/0098 : radio-opaque, e.g. radio-opaque markers
• CPC Class Codes: A61F 2310/00017 : Iron- or Fe-based alloys, e.g. stainless steel
• CPC Class Codes: A61F 2310/00023 : Titanium or titanium-based alloys, e.g. Ti-Ni alloys
• CPC Class Codes: A61F 2310/00029 : Cobalt-based alloys, e.g. Co-Cr alloys or Vitallium
• CPC Class Codes: A61F 2310/00137 : Tungsten or W-based alloys
• CPC Class Codes: A61F 2310/00149 : Platinum or Pt-based alloys

Abstract

This invention is a method of using a medical device. The device is a foldable stent or stent-graft which may be percutaneously delivered with (or on) a catheter, typically an endovascular catheter, to a body cavity or lumen and then expanded. The expandable stent structure utilizes torsional members which distribute bending and folding loads in such a way that the stent is not plastically deformed. The stent'"'"'s configuration allows it to be folded or otherwise compressed to a very small diameter prior to deployment without changing the length of the stent. The graft component cooperating with the stent is tubular and preferably is blood-compatible material which may, if desired, be reinforced with fibers. The stent is able to provide collapsible support for otherwise frangible graft material. When used with super-elastic alloys, the stent may be collapsed at a convenient temperature either above or, preferably, below the transition temperature of the alloy. The deployment procedures may involve the use of an outer sleeve to maintain the stent or stent-graft at a reduced diameter or may involve one or more external or internal "slip-lines" or "tether wires" to hold and then to release the device.

Claims

1. A method for introducing a self-expanding stent-graft into a lumen comprising the steps of:

providing a self-expanding stent-graft in a folded configuration and maintained in said folded configuration by a removable, longitudinally positioned slip line attached along a longitudinal fold edge, said graft comprising a collagen material;

introducing said folded self-expanding stent-graft to a selected site in a lumen; and

axially withdrawing said slip line in a direction substantially aligned with a longitudinal axis of said self-expanding stent-graft, thereby removing said slip line to allow the stent-graft to expand at the selected site in said lumen.

2. The method of claim 1 in which the selected site is a vascular site.

3. The method of claim 1 in which the self-expanding stent comprises loops along said fold line in the stent through which the slip line is introduced.

4. The method of claim 1 in which the stent is metallic.

5. The method claim 1 in which the stent comprises a super-elastic alloy.

6. The method of claim 1 in which the stent comprises a nickel-titanium alloy.

7. The method of claim 1 where the stent comprises a helically positioned undulating member forming multiple turns about a longitudinal axis of said stent-graft.

8. The method of claim 7 where said undulating member includes undulations and a flexible link passes through undulations on adjacent helical turns of said undulating member.

9. The method of claim 8 where said flexible link maintains said undulations in phased relationship between said adjacent helical turns.

10. The method of claim 1 where the graft further comprises a tubular member, said tubular member including reinforcing fibers.

11. The method of claim 1 where the graft further comprises a tubular member including radiopaque markers.

12. A method for introducing a self-expanding stent into a lumen comprising:

providing a self-expanding stent-graft in a folded configuration and maintained in said folded configuration by a removable, longitudinally positioned slip line woven along a longitudinal fold line of said folded configuration using a sack knot, said graft comprising collagen;

introducing said folded self-expanding stent-graft to a selected site in a lumen; and

axially withdrawing said slip line in a direction substantially aligned with said longitudinal fold line, thereby unweaving said slip line to allow the stent-graft to expand at the selected site.