Long-term effects of diltiazem and verapamil on mortality and cardiac events in non-Q-wave acute myocardial infarction without pulmonary congestion: Post hoc subset analysis of the multicenter diltiazem postinfarction trial and the Second Danish Verapamil Trial studies

The main objective of this retrospective analysis was to evaluate the long- term effect of the heart rate-lowering calcium antagonists verapamil and di ltiazem on the incidence of combined cardiac events and all-cause mortality in patients who had experienced a non-Q-wave acute myocardial infarction ( AMI), but who did not also have pulmonary congestion. In addition, factors having an independent association with these 2 outcomes were identified. Of 817 non-Q-wave patients, 81 (9.9%) died during 12 to 52 months of follow-u p. The unadjusted mortality rate was 42% lower in patients randomized to ca lcium antagonist therapy than placebo (7.2% vs 12.4%, p = 0.010). Non-Q-wav e patients who died during follow-up were older than patients who survived (62 vs 58 years, p = 0.001). Other factors found to have an independent ass ociation with all-cause mortality included diuretic use (RR 2.79), diabetes mellitus (RR 2.86), and New York Heart Association class >1 (RR 1.73). The covariate adjusted all-cause mortality risk ratio associated with randomiz ation to calcium antagonist therapy was 0.65 (95% confidence interval [0.40 to 1.05, p = 0.079]). Overall, 153 patients (18.7%) died or had nonfatal r einfarction. The unadjusted combined event rate was 31% lower in patients r andomized to calcium antagonist therapy than to placebo (15.2% vs 21.9%, p <0.006), Factors found to have an independent association with cardiac even ts included age, diabetes (RR 2.82), diuretic use (RR 2.04), and previous A MI (RR 1.71). In addition, randomization to the calcium antagonist group ha d a significant independent association with reduced cardiac events (p = 0. 031). The cavariate adjusted event rate RR associated with randomization to the calcium antagonist group was 0.69 (95% confidence interval [0.49 to 0. 97]). In conclusion, the heart rate-lowering calcium antagonists diltiazem and verapamil may play an important role in reducing long-term mortality an d reinfarction in non-Q-wave AMI without pulmonary congestion, (C) 2000 by Excerpta Medico, Inc.