Treatment with verapamil after an acute myocardial infarction. Review of the Danish studies on verapamil in myocardial infarction (DAVIT I and II)

Abstract

The effect of verapamil on death, reinfarctions, and major events, i.e. death or reinfarction after a myocardial infarction has been investigated in 2 Danish double-blind placebo-controlled verapamil infarction trials (DAVIT I and II). DAVIT I was an early intervention trial that demonstrated a statistically nonsignificant reduction in mortality and reinfarction after 6 months of treatment. DAVIT II was a later intervention trial that demonstrated a nonsignificant reduction in the 18-month mortality rate [p = 0.11, hazard ratio 0.80; 95% confidence limits (CL) 0.61 to 1.05], a significant reduction in the reinfarction rate (p = 0.04, hazard ratio 0.77; CL 0.58 to 1.03), and in the major event rate (p = 0.03, hazard ratio 0.80; CL 0.64 to 0.99) in the verapamil group compared with the placebo group. In patients without heart failure in the coronary care unit, a statistically significant reduction in the 18-month mortality rate (p = 0.02, hazard ratio 0.64; CL 0.44 to 0.94), the reinfarction rate (p = 0.02, hazard ratio 0.67; CL 0.46 to 0.97), and the major event rate (p = 0.01, hazard ratio 0.70; CL 0.52 to 0.93) was observed in the verapamil group compared with the placebo group. No significant differences were found in patients with heart failure. Meta-analyses of DAVIT I (for patients alive at day 8) and DAVIT II showed a statistically significant reduction in the odds ratio of mortality (22%), reinfarctions (27%), and the major event rate (21%) in verapamil-treated patients. It is concluded that long term treatment with verapamil after an acute myocardial infarction is associated with a significant reduction in overall mortality, major events, and reinfarctions, with the greatest effect in patients without heart failure.