Development of an ideal vascular replacement has been addressed with increasing urgency in recent years. To date, appropriate replacements for only large diameter bypass grafts have been realized, employing the use of Dacron and expanded polytetrafluoroethylene. A solution for small diameter (<6 mm I.D.) vessel bypass, however, has not yet been found. This is due mainly to acute thrombotic occlusion and chronic anastomotic hyperplasia that is introduced into these grafts due to the low blood flow velocities experienced by smaller caliber vessels and compliance mismatch between prosthetic and native vessel, respectively .