Self-expanding endoprosthesis
AssigneeCordis Corporation
InventorSteven D. Weier
Life of this patent
Estimating the term…
Abstract
A stent or other endoprosthesis is provided from a single strand of biocompatible and resilient material into which spring coils are formed by winding the strand through in excess of 360.degree.. The thus-formed coil springs are positioned along outside edges of the endoprosthesis, with legs joining the coil springs in order to form a generally zig-zag structure. When the endoprosthesis is compressed for endoluminal delivery, the coil springs allow for large angular deflection between adjoining legs while avoiding plastic deformation of the coil or of the legs.
Claims16
A self-expanding endoprosthesis for insertion into and implantation within a living body vessel, comprising:
- a continuous strand of biocompatible and resilient material, said strand formed into a generally cylindrical endoprosthesis which is self-expanding from a compressed orientation for delivery into a living body vessel so as to assume an expanded orientation, the expanded orientation being larger in circumferential degree than said compressed orientation and being an orientation at which the endoprosthesis is deployed into supporting engagement with an inside wall of the living body vessel;
- said continuous strand includes a plurality of alternating leg portions and coil portions, each said coil portion being a coil spring wound from said continuous strand to form a coil spring winding through in excess of 360.degree.;
- different ones of said leg portions have different lengths, one length defining a longer length leg portion and another length defining a shorter length leg portion, wherein one said shorter length leg portion and one said longer length leg portion are Joined together at one of said coil portions;
- and
- said coil portions are positioned so as to define at least one generally helical path of coil portions along the endoprosthesis.
A process for manufacturing a self-expanding endoprosthesis, comprising the steps of:
- providing a continuous strand of biocompatible and resilient material;
- winding said strand through in excess of 360.degree. so as to form a first coil spring portion therealong;
- repeating said winding step at a location spaced from said first coil spring portion in order to form a second coil spring portion which is spaced from said first coil spring portion by a predetermined distance and thus accomplishing a step of defining a leg portion of the endoprosthesis therebetween;
- said defining step provides legs of at least two different lengths in an alternating manner, said wrapping step proceeds through greater than 360.degree., and after said wrapping step, said configured strand pattern has a generally helical appearance;
- continuing said winding and defining steps until a desired number of coil spring portions are formed, in order to thereby form a configured strand pattern having the leg portions alternating with the coil spring portions;
- and
- wrapping said configured strand pattern through a generally cylindrical plane in order to form a generally cylindrical endoprosthesis.
Dependencies are inferred from the claim text.