Inhibition of Dipyridamole-Induced Myocardial Ischemia by Diltiazem in Patients with Coronary Artery Disease

We investigated the effect of diltiazem on dipyridamole-induced myocardial ischemia in eight patients with coronary artery disease. Dipyridamole was infused at a rate of 0.142 mg/kg/min for 4 min, and 87-lead mapping was performed to determine the number of leads with ischemic ST-segment depression greater than or equal to 0.05 mV (nST). The range of nST was 8-24 (mean, 13.8) in the control study. Of eight patients studied, a single dose of 90 mg diltiazem administered 3 h before dipyridamole infusion inhibited dipyridamole-induced ST-segment depression completely in seven (nST = 0) and incompletely in one (nST = from 24 to 5). It was concluded that diltiazem could suppress the myocardial ischemia following dipyridamole infusion.