Possible survival benefit from concomitant beta-but not calcium-antagonist therapy during reperfusion for acute myocardial infarction

Abstract

To test the hypothesis that long-term [beta]- or calciumantagonist 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 <= 0.001) and prior infarction (p <=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 <= 0.001) than their nontreated counterparts. Stepwise logistic regression analysis found significant independent correlations between inhospital death and the following variables: recurrent ischemia (p <= 0.001); proximal left anterior descending coronary infarct (p <= 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]-antagonist 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.