[Therapy with beta receptor blockers in myocardial infarct]

During the last 10-15 years, a total of 49 prospective, randomized, controlled studies have been performed to evaluate the efficacy and safety of early administered beta-receptor antagonists in patients with acute myocardial infarction. Those trials in which beta-receptor antagonists were administered intravenously followed by oral medication within 72 h after the onset of symptoms reported a significant reduction in early mortality (on average 13%; 95% confidence interval -2% to -25%). The efficacy of beta-receptor antagonists in reducing mortality was particularly obvious in patients at higher risk (i.e., older patients, previous infarction) with the maximal efficacy observed during the first 3-4 days of therapy. Similarly, there was a reduction in the incidence of reinfarction which averaged 19% for the patients treated with beta-receptor antagonists. The metaanalysis also showed a significant reduction in the incidence of nonfatal cardiac arrest due to primary ventricular fibrillation for the group receiving beta-receptor antagonists (average risk reduction 16%; 95% confidence interval -2% to -30%). As calculated on the basis of the ISIS-1 data, treatment with beta-receptor antagonists in approximately 200 patients with acute myocardial infarction would lead to the avoidance of one death, one reinfarction, and one episode of ventricular fibrillation. Based on these data, it is recommended that administration of beta-receptor antagonists should be an important adjunctive therapeutic modality in patients with acute myocardial infarction and no contraindications for this form of treatment.