Abstract
Nine randomized trials in patients with acute myocardial infarction have been performed to assess the effect of nifedipine on infarct size, reinfarction and/or survival. In none of the trials was there any benefit and in some there was a deleterious effect. In the most recent trial, SPRINT II, the study was stopped prematurely because of deleterious side effects in the diltiazem-treated group. Thus, nifedipine is not recommended in patients with acute myocardial infarction or postmyocardial infarction for prevention of reinfarction or death, and further trials are not necessary. In a single study involving 1,436 patients, verapamil showed no statistical benefit on reinfarction or survival, but due to a high drop-out rate, the result appears less than definitive. A second trial has been completed but results are not yeat available. In a randomized, double-blind short-term (2 weeks) trial consisting of 576 patients with non-Q-wave infarction, diltiazem caused a 50% reduction in the incidence of reinfarction and refractory angina. In a long-term trial (12-52 mos.) consisting of 2,466 patients with Q- and non-Q-infarction, there was no benefit overall, but in the patients without failure (80%) there was a 28% reduction in cardiac events. In the patients with non-Q-infarction (634), there was a 40% reduction in cardiac events, and at the end of 4-5 years there was still a reduction of 34% in the diltiazem group. In patients admitted to the study with failure, the mortality was increased in patients with Q- or non-Q-infarction. Thus, diltiazem is recommended for routine prophylaxis in patients with non-Q-infarction without cardiac failure.