various oral antiplatelet agents have been shown to reduce arterial thrombotic occlusion in a number of controlled clinical trials , e.g. , aspirin in transient ischemic attacks and unstable angina , aspirin and dipyridamole in saphenous vein coronary artery bypass and progression of peripheral vascular disease and dipyridamole in artificial heart valves .
C0007787
transient ischemic
C0004057
aspirin