Secondary Preventive Effects of a Calcium Antagonist for Ischemic Heart Attack

– Randomized Parallel Comparison With β-Blockers –

Abstract

Background: Beta-blockers (BB) have been widely used in the management of hypertension and acute myocardial infarction (AMI), and both national and international guidelines have recommended them as first-line agents. Calcium channel antagonists (CCA) are also effective in the treatment of hypertension and angina pectoris. However, the efficacy of CCA in the prevention of cardiovascular events in post-myocardial infarction (MI) patients in comparison to that of BB remains unclear. Methods and Results: A total of 120 post-MI patients (71 patients who were at least 1 month after the onset AMI and 49 stable coronary artery disease patients with a history of MI) were randomly assigned to receive a BB (atenolol, 25-50mg/day, n=60) or a CCA (benidipine, 4-8mg/day, n=60). All patients with AMI within the previous 1 month or with vasospastic angina were excluded from the present study. The baseline clinical characteristics were generally similar in the BB and CCA groups. The rate of primary composite outcome was 26.3% in the BB group in comparison to 13.3% in the CCA group, with no significant between-group differences (hazard ratio with the CCA group 0.640, P=0.276). Both treatments were well tolerated with few severe adverse events. Conclusions: CCA treatment was found to be as effective as BB in reducing cardiovascular events in post-MI patients. (Circ J 2011; 75: 1696-1705)