Atherosclerotic cardiovascular disease is the number one cause of morbidity and mortality in the western world. This may lead to arterial stenosis which may ultimately lead to occlusion. When this occurs, the consequences range from gangrene, to stroke or to myocardial infarction. At the moment, autologous saphenous veins are the treatment modality of choice in low blood flow vessels such as the coronary arteries and infrapopliteal vessels. However, in many cases the saphenous vein is either unsuitable or unavailable (due to previous stripping). In such a setting, the need for a compliant vessel prosthesis is vital. We propose to test in experimental animals a compliant, microporous small vessel prosthesis which has shown a low thrombogenic profile as well as a high biocompatibility index in preliminary trials. The compliant small vessel graft (4 mm I.D.) will be fabricated from our patented biodurable polyurethane tradenamed ChronoFlex. The proposed grant will be evaluated in vivo by well-accepted techniques. The universal benefit of this research would be to create a clinically acceptable and hyperplasia- resistant small diameter prosthetic vascular graft. PROPOSED COMMERCIAL APPLICATION: A major market exists for the development of a compliant small vessel prosthesis. Currently, there are no clinically acceptable synthetic small vessel prostheses. If such a prosthesis could be used for both peripheral and coronary applications, the synthetic vascular graft market could grow to $750 million annually.