초록

A self-expanding stent formed from helically wound and braided filaments of bioabsorbable polymers such as PLA, PLLA, PDLA, and PGA.

대표청구항 ▼

[ What is claimed is:] [1.]1. A bioabsorbable implantable stent having a tubular, radially compressible and self-expandable braided and annealed structure comprising:a first set of between 5 and 18 filaments each of which extends in a helix configuration along a center line and having a first common

[ What is claimed is:] [1.]1. A bioabsorbable implantable stent having a tubular, radially compressible and self-expandable braided and annealed structure comprising:a first set of between 5 and 18 filaments each of which extends in a helix configuration along a center line and having a first common direction of winding;a second set of filaments of the same number as the first set, each of which extends in a helix configuration along the center line and having a second common direction of winding;the second set of filaments crossing the first set of filaments at an axially directed angle of between about 120 and about 150 degrees when in a first free radially expanded state after being annealed but before being loaded on a delivery device so as to form a plurality of interstices between filaments, and further to determine an annealed diameter, D, of the stent in said first free radially expanded state;each filament comprising at least one of poly-L-lactide, poly-D-lactide, polyglycolide and combinations thereof, and having a substantially solid and substantially uniform cross-section, a tensile strength of from about 40 ksi to about 120 ksi, a tensile modulus of from about 400,000 psi to about 2,000,000 psi, and an average diameter of from about 0.15 mm to about 0.6 mm;wherein the first set of filaments and second set of filaments act upon one another to create an outwardly directed radial force sufficient to implant the stent in a body vessel upon deployment from the delivery device; andwherein said radial force, when the stent is radially constrained to a predetermined fraction of the annealed diameter, varies substantially linearly as a function of the annealed diameter, whereby said annealed diameter, D, is selected to provide a desired radial force when the stent is so radially constrained.