MEDICAL DEVICE

摘要

A stent with rapid return and strong shape memory prevents migration of the stent out of a desired site within a patient's body due to peristaltic actions. One particular stent includes an elongated member which defines an eccentric lumen extending longitudinally therethrough such that a first wall portion of the elongated member is thicker than a second wall portion of the elongated member. The first wall has a stronger shape memory than the second wall, and it recoils faster than the second wall. Another particular stent includes a co-extruded elongated member. The elongated member comprises a first material co-extruded with a second material where the second material forms at least a portion of a wall of the elongated member. The second material can have a higher modulus of elasticity than the first material. Additionally or alternatively, the second material can include a shape memory material.