Vasomotor response to ergonovine of epicardial and resistance coronary arteries in the nonspastic vascular bed in patients with vasospastic angina

The hypothesis that a coronary vasomotion disorder may exist in the entire coronary artery tree in patients with vasospastic angina was investigated by examining the coronary responses to atrial pacing (130 beats/min) before and after the administration of ergonovine (16 μg) into nonspastic coronary arteries. Seven patients with angiographically normal coronary arteries and focal spasm in the right coronary artery and 7 control patients with atypical chest pain and angiographically normal coronary arteries without spasm were studied. Great cardiac vein flow (GCVF) and left anterior descending coronary artery diameters (CDs) were measured by the thermodilution method and quantitative arteriography, respectively. Although the CDs before ergonovine were similar in the 2 groups, the pacing-induced increase in GCVF before ergonovine administration was smaller in patients with vasospastic angina than in control patients (22 ± 4% vs 49 ± 11%, respectively; p