To complement ongoing studies including angioscopy and Laser-tissue interactions, it has become necessary to develop a reproducible animal model of atherosclerosis. To test prototype multifunctional catheters in an attempt to simulate uniclinical conditions, we have employed a variety of models in the animal laboratory. Thusfar, 14 miniature swine have been placed as combination of atherogenic diet (cholesterol levels 500-1,000 mg/dl mg/dl) and intravascular balloon endothelial denudation performed under fluoroscopy utilizing sterile surgical techniques. From a single femoral arterial cutdown, balloon denudation was performed in carotid and iliofemoral arteries bilaterally. Angiograms obtained immediately after balloon-induced barotrauma revealed varked vasospasm of the affected vessels. We have examined several animals at one-three months after the initial procedure who have died for various reasons during the maturation phase of the study. Intense and advanced focal atherosclerotic lesions were observed at the sites of balloon denudation consisting of calcified, organized thrombus and "human" appearing antherosclerotic morphology. In addition, we have performed balloon denudation in the aorta and iliofemoral system of 20 New Zealand white rabbits also receiving an atherogenic diet. Necropsy specimens in several rabbits who died weeks after the procedure, revealed less intense fatty streak lesions in the aorta with more focal hemodynamically significant abnormalities in the iliac vessels. We believe that these two models of atherosclerosis are well suited to help study the feasibility of in vivo laser angioplasty.