Implantable medical device having reduced chance of late inflammatory response

摘要

The invention provides a method for fabricating an implantable medical device to increase biocompatibility of the device, the method comprising: heat setting a polymer construct, wherein the polymer construct is at a temperature range of from about Tg to about 0.6(Tm−Tg)+Tg such that the set polymer construct comprises a crystalline structure having crystals at a size less than about 2 microns; and fabricating an implantable medical device from the heat set polymer construct.

主权项

1. A biodegradable stent comprising:
a cylindrically-shaped scaffold comprising a biodegradable polymer including a poly(L-lactide) based polymer, wherein the scaffold includes a pattern comprising a network of interconnected struts, the pattern formed by cutting a tube including the poly(L-lactide) based polymer, wherein a crystallinity of the tube is increased by processing, the processing comprising heating and radially expanding the tube prior to forming the pattern, wherein the scaffold has induced molecular orientation in the circumferential direction due to the radially expanding, wherein the biodegradable polymer after the processing has a crystallinity between 5% and 60% and comprises crystals dispersed in an amorphous domain, the crystals having a size less than 10 microns, and wherein the scaffold is radially expandable and has adequate radial strength from the increased crystallinity and induced circumferential orientation to hold open a blood vessel in a body when the scaffold is radially expanded in a blood vessel.