Effects of a Single Oral Dose of Cilostazol on Epicardial Coronary Arteries and Hemodynamics in Humans.

Cilostazol, a novel cyclic adenosine monophosphate phosphodiesterase type III inhibitor, has been developed as an antiplatelet drug with a vasodilating action on peripheral arteries. The present study was designed to test, in humans, whether cilostazol can dilate the epicardial coronary arteries and what are its hemodynamic effects. Eight patients with chest pain syndrome were subjected to serial quantitative coronary arteriography immediately before and at 30, 60 and 150min after a single oral dose of cilostazol (200mg). Luminal cross-sectional areas (mm2) at the proximal and distal sites of major coronary arteries (6 segments at each sampling time) were significantly increased at 150 min after taking the drug. The percent increases relative to the baseline values were 25+/-7 (6.8+/-0.8-->8.3+/-1.0*) and 42+/-7% (2.1+/-0.3-->3.0+/-0.4*) in the right coronary artery, 24+/-5 (5.1+/-0.7-->6.1+/-0.8*) and 28+/-10% (1.6+/-0.31-->9+/-0.3*) in the left anterior descending artery, and 14+/-6 (5.9+/-0.9-->6.6+/-0.9*) and 24+/-10% (1.3+/-0.2-->1.5+/-0.2*) in the left circumflex artery, respectively (*p<0.05 vs baseline). This action, relative to that of nitroglycerine, was between 27% and 54%. Moreover, small but sustained decreases in systolic pulmonary pressure and stroke work index were observed. Thus, cilostazol has a mild coronary vasodilating action with minimal hemodynamic effects, thereby giving it a possible role in the treatment of coronary artery disease.