A model for testing transluminal recanalization techniques was developed. Human atherosclerotic arteries were transplanted in dogs and evaluated by angiographic and histologic study within a 12-wk period. An inflammatory response was most intense within the first 2 wk. By 12 wk, no inflammation was noted. The model has several advantages: The pathologic characteristics are those of a human coronary artery. Thrombus formation is frequent, with progression to a well organized dense fibrocellular vascular occlusion within 4-12 wk. The arterial occlusion resembles human vascular disease. The vascular occlusions are readily accessible with standard catheterization technique. The model is easy to produce within a short period. The model was used to evaluate laser recanalization of vascular obstructions.