The Thrombolysis in Myocardial Ischemia Trial (TIMI III) focused on unstable angina and non-Q-wave myocardial infarction. The trial was designed to determine by coronary arteriography the incidence of coronary thrombi in these conditions and the response of these thrombi to tissue-type plasminogen activator (t-PA) in TIMI IIIA and the effects of thrombolytic therapy and of an early invasive strategy on clinical outcome in TIMI IIIB. There was also a registry with two components. A roster enumerated all patients with unstable angina or non-Q-wave myocardial infarction enrolled at cooperating hospitals. From the roster, a study population of 1,893 subjects was selected and followed prospectively for the year to determine incidence of death or myocardial infarction.