To test the hypothesis that long-term beta- or calcium-antagonist therapy begun before the time of myocardial infarction and coronary reperfusion might improve patient in-hospital survival compared with reperfusion alone, 424 consecutive patients successfully reperfused with coronary angioplasty within 12 hours of infarct symptom onset were carefully and retrospectively characterized. Forty-seven patients (11%) were taking beta antagonists and 74 patients (17%) were taking calcium antagonists at the time of infarction. Patients receiving beta antagonists had a more frequent history of hypertension (p less than or equal to 0.001) and prior infarction (p less than or equal to 0.01) than those not so treated and patients receiving calcium antagonists had a more frequent history of prior infarction, prior angina, hypertension and diabetes (all p less than or equal to 0.001) than their nontreated counterparts. Stepwise logistic regression analysis found significant independent correlations between in-hospital death and the following variables: recurrent ischemia (p less than or equal to 0.001); proximal left anterior descending coronary infarct (p less than or equal to 0.001); 3-vessel disease (p = 0.002); patient age (p = 0.004); and initial total occlusion of the infarct artery (p = 0.022). After adjustment for these factors, beta antagonist use (mortality = 0 vs 8% without treatment) was still significantly correlated with improved survival (p = 0.048), whereas calcium-antagonist therapy made no difference in survival. Heart rate and left ventricular end-diastolic pressure upon presentation were significantly lower in patients treated with beta antagonists. Thus, beta-antagonists therapy, but probably not calcium-antagonist therapy, taken before reperfusion for acute myocardial infarction, may improve early survival compared to reperfusion alone. Larger studies will be required to confirm or refute these observations.