Risks and benefits of early treatment of acute myocardial infarction with an angiotensin-converting enzyme inhibitor in patients with a history of arterial hypertension: Analysis of the GISSI-3 database

Background Many trials have proved the benefits of early systematic treatment with angiotensin-converting enzyme inhibitors in patients with acute myocardial inforction (AMI). Pathophysiological studies, however, suggest potential harm in excessive reduction of blood pressure (BP) in hypertensive patients with ischemic heart disease. Methods We analyzed data from the GISSI-3 (Gruppo Italiano per lo Studio della Sopravvivenza nell'Infarto miocardico) trial to assess the effects of early treatment with angiotensin-converting enzyme inhibitors during AMI in patients with a history of hypertension compared with normotensive patients. The trial randomly assigned 19,394 patients to 6 weeks of lisinopril treatment or control, starting treatment within 24 hours of AMI onset. Results In the 10,661 normotensive patients, lisinopril significantly reduced lethal events, but in the 7362 hypertensive patients, a higher rate of lethal events was reported the first day of treatment, and the benefits only appeared subsequently. These results may be attributable to the subgroup of 1165 hypertensive patients with low baseline systolic BP (lower quintile, BP < 120 mm Hg), in whom critical hypotension was more prone to develop after lisinopril treatment. In fact, these patients showed a higher mortality rate as the result of an excess of cardiogenic shock during the first day of lisinopril treatment (odds ratio 3.07, 95% CI 1.39-6.77) and a persistent, unfavorable death trend after 6 weeks. Conclusions These data suggest that caution should be exercised when using lisinopril in the acute phase of a myocardial infarction in patients with a history of hypertension but low systolic BP at presentation.