The acute thrombogenicity of a compliant polyurethane arterial graft compared with autologous vein. An experimental study in sheep.

The acute thrombogenicity of a new type of polyurethane urea graft was compared with that of autologous femoral vein graft in a sheep carotid artery interposition model. There was significantly more thrombus formation (as measured from thrombus weight and thrombus-free surface) and greater platelet accumulation in the polyurethane graft. Despite flow restriction to 25 ml/min, the patency rates after 4 hours were similar; all veins were patent and only one of the eight polyurethane grafts was occluded.