Background: As a result of randomized controlled trials with calcium channel blockers after myocardial infarction, concern has developed that these agents are associated with an increased risk of cardiovascular events, particularly in the presence of left ventricular dysfunction.
Methods: To test the hypothesis that calcium channel blockers increase cardiovascular events in such patients, the incidence of all-cause mortality, cardiovascular death, severe heart failure, and recurrent infarction was examined in 940 patients taking calcium channel blockers and 1180 not taking them 24 hours before randomization to placebo or captopril in the Survival and Ventricular Enlargement (SAVE) Trial. All patients had an ejection fraction < or =40%. Relative risks for calcium channel blocker users versus nonusers and the 95% confidence intervals were computed with univariate and multivariate Cox regressions. Adjustments were made for differences in baseline covariates.
Results: For all causes of mortality, the relative risk for calcium channel blocker users versus nonusers was 0.96, with the 95% confidence interval of 0.78 to 1.17. In the SAVE placebo and captopril groups, the relative risks for the development of severe heart failure among the calcium channel block users versus nonusers were 0.95 and 1.23, with the 95% confidence interval of 0.72 to 1.25 and 0.88 to 1.71, respectively. A similar neutral result held for patients with and without a history of hypertension. Furthermore, calcium channel blockers did not alter the benefit of the angiotensin converting enzyme inhibitor, captopril.
Conclusions: This analysis of the nonrandomized clinical use of calcium channel blockers in the postmyocardial infarction population with left ventricular dysfunction did not identify either a clinical deterioration or improvement with respect to subsequent cardiovascular events.