Safety of beta-blocker therapy with and without thrombolysis:A comparison of bisoprolol and atenolol in acute myocardial infarction

In the current era of widely used thrombolytic therapy, the new betablocker bisoprolol was compared with the well-established betablocker atenolol in the treatment of acute myocardial infarction (AMI), A total of 334 patients were enrolled in this international, multicenter, randomized, double-masked, controlled study of 7 days' duration in two parallel groups, The purpose of the study was to compare the tolerability and safety of the two beta-blockers given to patients with AMIs who either were (281 patients) or were not (53) given concurrent thrombolytic agents, A statistically significant decrease in heart rate was seen with both bisoprolol and atenolol, Beta-blocker therapy had to be interrupted in 70 patients, 36 receiving bisoprolol and 34 atenolol, because of serious adverse effects, The difference in incidence of adverse events between groups was not significant, A logistic regression analysis based on conditions at admission predicted an increase in the risk of critical events occurring during the first week after an AMI for patients with a positive family history of AMI, a moderate-sized myocardial infarction, or a heart rate >70 beats/min, and for patients pretreated with dihydropyridine calcium antagonists, Bisoprolol was found to be as effective as atenolol in reducing heart rate, an important goal of intervention in AMI. Furthermore, some characteristics that might influence the decision to use beta-blockers in addition to thrombolytic agents were identified