- Required to have documented atherosclerosis in at least 1 vascular territory defined as: at least moderate (>3.9mm) aortic atherosclerosis seen on transesophageal echocardiography; or moderate coronary artery disease (>50% lesion) in at least 1 coronary artery seen at cardiac catheterization; or >50% carotid lesion seen on ultrasound; or clinically documented peripheral vascular disease.