Myocardial infarction (MI): Aspirin (160-300 mg/day) therapy started immediately after the onset, with or without simultaneous coronary arterial thrombolytic therapy, reduces the mortality rate in vascular diseases, including MI, and prevents reinfarction. Maintenance therapy with the same dosage is also recommended. 2) Angina pectoris: In unstable angina, aspirin in a dose of 300 mg/day for 2 years reduces the mortality and the incidence of MI. Ticlopidine decreases anginal attacks in a few cases of angina at rest. 3) Coronary artery bypass grafting (CABG): Long-term administration of 325 mg aspirin/day should be started on the day of surgery and combined with 200-400 mg dipyridamole/day administered from 2 days before to 1 week after the surgery. 4) Percutaneous transluminal coronary angioplasty (PTCA): Current antiplatelet drugs prevent post-procedural acute coronary occlusion but not late restenosis.