Efficacy of zofenopril in combination with amlodipine in patients with acute myocardial infarction: a pooled individual patient data analysis of four randomized, double-blind, controlled, prospective studies.

Objective: In the four SMILE (Survival of Myocardial Infarction Long-Term Evaluation) studies, early administration of zofenopril in acute myocardial infarction (AMI) showed beneficial effects as compared to placebo and other angiotensin converting enzyme inhibitors (ACEIs). This study investigated whether the concomitant administration of the dihydropyridine calcium channel-blocker amlodipine may improve zofenopril efficacy to prevent cardiovascular events in post-AMI patients.
Methods: This was a post-hoc analysis of pooled individual patient data from the four large randomized SMILE studies. The primary endpoint was the 1-year combined occurrence of death or hospitalization for cardiovascular causes.
Results: In total, 3488 patients were considered, 303 (8.7%) treated with concomitant amlodipine. Baseline systolic blood pressure and prevalence of metabolic syndrome were higher in amlodipine treated patients. The 1-year occurrence of major cardiovascular outcomes was significantly reduced in patients receiving concomitant treatment with amlodipine (hazard ratio, HR = 0.66; and 95% confidence interval, CI = 0.44-0.98; p = .039). After accounting for treatment with amlodipine, the risk of cardiovascular events was significantly reduced with zofenopril compared to placebo (HR = 0.78; 95% CI = 0.63-0.97; p = .026]. Among ACEI-treated patients, the zofenopril plus amlodipine combination reduced the risk of cardiovascular events by 38%, compared to the combination of other ACEIs plus amlodipine [HR = 0.76; 95% CI = 0.61-0.94); p = .013). The prognostic benefit of concomitant treatment with zofenopril plus amlodipine was independent from blood pressure lowering.
Conclusions: Zofenopril had a positive impact on prognosis in post-AMI patients, compared to other ACEIs. Concomitant administration of amlodipine may help to reduce the risk of cardiovascular events at 1 year.