VENTRICULAR ARRHYTHMIAS IN THE ACUTE AND CHRONIC PHASES AFTER ACUTE MYOCARDIAL-INFARCTION - EFFECT OF INTERVENTION WITH CAPTOPRIL

Background Ventricular arrhythmias (VAs) are independent predictors of mortality in survivors of myocardial infarction (MI), and they are mo re likely to be induced in dilated hearts with increased wall stress. Angiotensin-converting enzyme (ACE) inhibitors have been shown to prev ent progressive dilation of the left ventricle after MI. Methods and R esults The effects of captopril were evaluated in 58 patients with lef t ventricular (LV) dysfunction after MI. Patients were randomized on d ay 7 to either placebo or captopril (50 mg daily) in a double-blind pa rallel study over a period of 6 months. Patients were followed up by m eans of ambulatory ECG monitoring and echocardiography. There was a si gnificant increase in VA in the placebo group (P<.05) in contrast to a significant decrease in the captopril group (P<.05). As a consequence , there was a significant between-group difference after 6 months (P<. 05). Furthermore, the number of patients without VA at baseline who pr esented with this at the completion of the study was 6% in the captopr il group versus 38% in the placebo group (P<.05). At baseline as well as at the termination of the study, LV end-diastolic volume index (LVE DVI) and W end-systolic volume index (LVESVI) were significantly incre ased among patients with VA (P<.01). On day 180, both myocardial ische mia and an increase in the LVEDVI were independent predictors of VA; h owever, progressive dilation of the left ventricle was confined to the placebo patients with significant increases in the LVEDVI compared wi th the captopril group: 17% versus 0%, respectively (P<.01). Furthermo re, the duration of ambulatory ST-segment depression was significantly longer in this group compared with the captopril group (P<.01).