Medical stents for body lumens exhibiting peristaltic motion

• US 5,876,445 A
• Filed: 11/26/1996
• Issued: 03/02/1999
• Est. Priority Date: 10/09/1991
• Status: Expired due to Fees

• Current Assignee: Boston Scientific Corporation
• Original Assignee: Boston Scientific Corporation
• Inventors: Andersen, Erik, Strecker, Ernst Peter, Hess, Kathleen L., Urhoj, Susanne
• Primary Examiner(s): BRITTINGHAM, DEBRA
• Application Number:
  US08/756,456
• Time in Patent Office: 826 Days
• Field of Search: 623/1, 623/11, 623/12, 606/194, 606/195, 606/198, 606/191
• US Class Current: 623/23.7
• CPC Class Codes: A61F 2/0077 Special surfaces of prostheses, e.g. for improving ingrowth A61F2/30767 takes precedence
• CPC Class Codes: A61F 2/04 Hollow or tubular parts of organs, e.g. bladders, tracheae, bronchi or bile ducts A61F2/18, A61F2/20 take precedence; devices, other than stent-grafts, providing patency to, or preventing collapsing of, tubular structures of the body other than stent-grafts, e.g. stents A61F2/82; instruments specially adapted for placement or removal of stents or stent-grafts A61F2/95
• CPC Class Codes: A61F 2/07 Stent-grafts
• CPC Class Codes: A61F 2/90 characterised by a net-like or mesh-like structure
• CPC Class Codes: A61F 2/95 Instruments specially adapted for placement or removal of stents or stent-grafts
• CPC Class Codes: A61F 2/9522 Means for mounting a stent or stent-graft onto or into a placement instrument
• CPC Class Codes: A61F 2/958 Inflatable balloons for placing stents or stent-grafts
• 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 2002/9511 the retaining means being filaments or wires
• 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 2210/0076 multilayered, e.g. laminated structures
• CPC Class Codes: A61F 2230/0013 Horseshoe-shaped, e.g. crescent-shaped, C-shaped, U-shaped
• CPC Class Codes: A61F 2230/0078 hyperboloidal
• CPC Class Codes: A61F 2250/0067 Means for introducing or releasing pharmaceutical products into the body
• CPC Class Codes: A61L 31/005 Ingredients of undetermined constitution or reaction products thereof
• CPC Class Codes: A61L 31/04 Macromolecular materials
• CPC Class Codes: D04B 1/225 Elongated tubular articles of small diameter, e.g. coverings or reinforcements for cables or hoses
• CPC Class Codes: D04B 15/14 Needle cylinders
• CPC Class Codes: D10B 2509/06 Vascular grafts; stents

Abstract

Methods for forming, shaping and heat treating stents for reinforcement of the lumen of peristaltic organs. The stent is formed by knitting preferably a nitinol wire into a pattern of overlapping loops selected such that from a relaxed state each row of loops may shift axially relative to and independently of the rows on either side. This local lengthening and shortening accommodates peristalsis of the organ without migrating within the organ.

Claims

1. A medical device for use in a body lumen, comprising:

a flexible wire configuration to form a wall of a cylindrical tube over a predetermined length, the gauge of said wire varying along said tube,

said tube having at least one permanently deformed end portion increased to a diameter larger than remaining portions of said tube,

said tube being in an annealed state under which strains induced by deforming said end portion have been relieved, so that a configuration of said end portion is stabilized, and

said at least one increased diameter end portion being constructed and arranged, upon insertion into said body lumen, to apply anchoring pressure upon the wall of said lumen to secure fixation of said tube in said lumen.