Verapamil reduces dipyridamole-induced myocardial ischemia in patients with coronary artery disease

The aim of this study was to evaluate the effects of verapamil administration on dipyridamole-induced transient wall-motion abnormalities as detected by two-dimensional echocardiographic monitoring in patients with coronary artery disease. Twenty-eight patients (16 men and 12 women; mean age, 60 +/- 7 years) with angiographic evidence of significant coronary artery disease, positive dipyridamole echocardiography test results at basal condition on two consecutive days, were prospectively studied Patients were randomized to verapamil (360 mg/day) or placebo treatments, given in three divided doses daily for 7 days; at the end of this time, each patient crossed over to the alternate regimen. Dipyridamole echocardiographic testing was repeated at the end of each treatment period. Our data demonstrate that verapamil significantly reduces the dipyridamole-induced wall-motion score index, a quantitative marker of acute myocardial ischemia (1.7 +/- 0.4 vs. 1.3 +/- 0.2; p < 0.001), Hemodynamic data show that the drug reduces heart rate and rate-pressure product at basal condition (heart rate from 75 +/- s to 67 +/- 9 beats/min; p < 0.001; rate-pressure product from 99 +/- 13 to 86 +/- 13 U x 10(-2); p < 0.001) and at peak dipyridamole infusion (heart rate from 96 +/- 8 to 89 +/- 6 beats/min; p < 0.001; rate pressure product from 127 +/- 21 to 118 +/- 13 U x 10(-2); p < 0.05) with respect to placebo treatment. We conclude that verapamil is able to reduce dipyridamole-induced ischemia, as detected by two-dimensional echocardiographic monitoring, in patients with coronary artery disease by reducing, at least partially, myocardial oxygen consumption. Moreover, its beneficial action could be related to the effects of the drug on coronary collateral circulation and on sympathetic modulation.