THERAPEUTIC EFFECTS OF CAPTOPRIL ON ISCHEMIA AND DYSFUNCTION OF THE LEFT-VENTRICLE AFTER Q-WAVE AND NON-Q-WAVE MYOCARDIAL-INFARCTION

Treatment with angiotensin-converting enzyme inhibitors has a benefici al effect on myocardial ischemia and left ventricular dysfunction afte r myocardial infarction. The effect of captopril on myocardial ischemi a was evaluated in 58 patients with left ventricular dysfunction (ejec tion fraction <45%) after Q-wave or non-Q-wave myocardial infarction i n a placebo-controled, parallel, double-blind study. Patients were ran domized on day 7 to either placebo or captopril (50 mg daily) and moni tored for a period of 180 days by serial echocardiography and ambulato ry ST-segment monitoring. There was a significant effect of captopril on the duration of ambulatory ST depression during the 180 days: The v alues per day were reduced from 28 +/- 5 min at baseline to 2 +/- 1 mi n on day 180 in the Q-wave group (p < 0.01) and from 39 +/- 10 min at baseline to 6 +/- 1 min on day 180 in the non-Q-wave group (p < 0.05). In the placebo group the duration of ST depression on day 180 were 21 +/- 8 min in the Q-wave group and 22 +/- 7 min in the non-Q-wave grou p, thus being significantly higher as compared with the corresponding captopril groups (p < 0.01 and p < 0.05, respectively). In the placebo Q-wave group there was a significant increase in left ventricular end -diastolic volume index from 74 +/- 3.5 to 89 +/- 4.5 ml/m(2) (p < 0.0 1) during the study period, which was in contrast to unchanged values of 75.5 +/- 3.0 and 75.0 +/- 3.5 ml/m(2) (not significant [NS]) in the captopril Q-wave group. There were no volume changes in either of the two non-Q-wave groups. In the Q-wave infarct group there was a positi ve correlation between the percentage changes in left ventricular end- diastolic volume index and the duration of ST depression (rho = 0.74, p < 0.001). There was no such correlation in the non-Q-wave group (rho = 0.19, NS). The results indicate an antiischemic effect Of captopril mediated by prevention of left ventricular dilatation in Q-wave infar ctions and an antiischemic effect independent of volume as demonstrate d in non-Q-wave infarctions. Thus angiotensin-converting enzyme-inhibi tion should probably be used more widely after myocardial infarction. (AM HEART J 1994;127:1-7.)