Aspirin, Heparin, or Both to Treat Acute Unstable Angina

We tested the usefulness of aspirin (325 mg twice daily), heparin (1000 units per hour by intravenous infusion), and a combination of the two in the early management of acute unstable angina pectoris in a double-blind, randomized, placebo-controlled trial involving 479 patients. The patients entered the study as soon as possible after hospital admission (at a mean [±SD] of 7.9±8.0 hours after the last episode of pain), and the study was ended after 6±3 days, when definitive therapy had been selected. Major end points — refractory angina, myocardial infarction, and death — occurred in 23,12, and 1.7 percent of the 118 patients receiving placebo, respectively. Heparin was associated with a decrease in the occurrence of refractory angina (P = 0.002). The incidence of myocardial infarction was significantly reduced in the groups receiving aspirin (3 percent; P = 0.01), heparin (0.8 percent; P