STENT HAVING A PROGRAMMED PATTERN OF (IN VIVO) DEGRADATION

摘要

The present invention provides a biodegradable polymeric stent having a programmed pattern of in vivo degradation. When deployed, the stent comprises a substantially cylindrical element having two open ends and a plurality of regions circumferentially spaced around the cylindrical element and extending from one open end to the other open end of the cylindrical element. Each of the regions is configured to have a desired in vivo lifetime. One region is designed to have a shorter in vivo lifetime than the other region or regions so that when the stent is deployed within the lumen of a vessel of a patient, the cylindrical element breaks apart from one open end of the cylindrical element to the other open end of the cylindrical element within a predetermined period of time after the stent is deployed in the patient. In one preferred embodiment the stent is a formed from a biodegradable polymeric band. The band includes a head having a slot and a tongue having a catch mechanism. The cylindrical element is formed by inserting a portion of the tongue through the slot to provide a cylindrical element having a first reduced diameter configuration. Following deployment, the cylindrical element is in a second expanded diameter configuration wherein the distal catch mechanism engages the inner surface of the head and prevents radial collapse or recoil of the polymeric stent. In a second preferred embodiment, the stent is formed from a plurality of interconnected polymeric bands.