A comparison of intervention with losartan or captopril in acute myocardial infarction

Angiotensin-converting enzyme (ACE) inhibitors prolong life, lower the progression of heart failure, and decrease the need for hospitalizations in patients after myocardial infarctions. It is still unclear whether these effects could also be achieved by blocking the angiotensin II (ATII) type 1 receptor.

We randomized 201 patients with acute myocardial infarction treated with either direct angioplasty, thrombolysis, or heparin alone to the ACE inhibitor captopril or the ATII antagonist losartan. The primary endpoints were safety, tolerability, and left ventricular parameters. The patients were followed for at least 15 days. The incidence of severe adverse events was similar in both groups, although cough presented less often in the losartan group. Captopril failed to prevent an increase in end-diastolic volume and did not influence left ventricular end-systolic volume. This effect led to an increase in the left ventricular ejection fraction (P<0. 001) without a change in wall-motion index. Losartan did not affect end-diastolic volume but decreased end-systolic volume (P<0.001), resulting in a significant increase in left ventricular ejection fraction (P<0.001) and a decrease in wall-motion index (P<0.001).

This study suggests that losartan is safe and well tolerated in patients after myocardial infarction. ATII antagonists seem to have a more pronounced effect on left ventricular remodeling than ACE inhibitors.