Aims: Many clinical trials conducted in the 1970s and early 1980s have shown that the long-term use of beta-blockers after an acute myocardial infarction significantly reduces mortality and reinfarction rates. This study assessed the impact of these findings in clinical practice.
Methods: We retrospectively analysed the beta-blocker prescriptions for 36,817 patients with acute myocardial infarction included in three large randomized clinical trials (Gruppo Italiano di Studio sulla Sopravvivenza nell'Infarto Miocardico--GISSI, 1, 2, and 3), conducted by a highly representative sample (about 75%) of Italian coronary care units in 1984-85, 1988-89 and 1991-93.
Results: The prescription of beta-blockers at discharge increased gradually from 8.5% in 1984-85 to 25.0% in 1988-89 and to 31.4% in 1991-93. A similar trend was apparent for beta-blocker prescriptions 6 months after acute myocardial infarction. The strongest predictors of beta-blocker prescription are the presence of post-infarctual angina and a history of arterial hypertension. Besides the classical contraindications, advanced age, transitory cardiac failure or arrhythmias in the acute phase of acute myocardial infarction are important predictors of nonprescription.
Conclusion: The use of beta-blockers after acute myocardial infarction in Italy has increased more than three-fold in the last decade, but they are still prescribed to too few patients, especially those at higher risk, for whom the expected benefit is greater.