Luminal graft endoprostheses and manufacture thereof

Claim 1

A luminal endoprosthesis for deployment within a living body pathway, comprising: a tubular expandable support element with a longitudinal axis, an external generally cylindrical surface and an internal generally cylindrical surface, said support element being expandable from a first diameter at which it is adapted to be inserted into a living human or animal body pathway a second diameter, the second diameter being greater than the first diameter, said expandable support element being capable of supporting walls of the living body pathway when at the second diameter, said second diameter being 1.5 to 12 times greater than said first diameter of the expandable support element; an expandable porous coating made from an essentially inert biocompatible material, said expandable coating being applied over at least one of said external and internal generally cylindrical surfaces of the expandable support element; said tubular expandable support element extending substantially the full length of the expandable porous coating; the expandable coating is made from porous material having pores that open when the tubular support element expands from said first diameter to said second diameter to provide open pores which allow normal cellular invasion thereinto from the body pathway when implanted therewithin; said expandable porous coating is an elastomeric fibrous material of elastomeric fibers, said fibers being essentially inert and each is linear and oriented at an angle β with respect to the longitudinal axis of the tubular support element when at its first diameter, said angle β being less than about 80°; said elastomeric fibers being arranged in a plurality of at least 10 layers of superimposed fibers, each fiber of which extends substantially the length of said tubular support element, with the fibers in each of the superimposed layers being oriented in such a manner that they cross the fibers of at least an upper neighboring layer or at least a lower neighboring layer in order to provide crossed fibers; and said crossed fibers reorient with respect to one another when the tubular support element expands such that said angle β of each fiber increases and thereby defines said pores that open when the tubular support element expands from said first diameter to said second diameter and that are thus oriented to allow said normal cellular invasion.