VASOMOTOR RESPONSE TO ERGONOVINE OF EPICARDIAL AND RESISTANCE CORONARY-ARTERIES IN THE NONSPASTIC VASCULAR BED IN PATIENTS WITH VASOSPASTICANGINA

The hypothesis that a coronary vasomotion disorder may exist in the en tire coronary artery tree in patients with vasospastic angina was inve stigated by examining the coronary responses to atrial pacing (130 bea ts/min) before and after the administration of ergonovine (16 mu g) in to 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 n ormal coronary arteries without spasm were studied. Great cardiac vein now (GCVF) and left anterior descending coronary artery diameters (CD s) were measured by the thermodilution method and quantitative arterio graphy, 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 i n control patients (22 +/- 4% vs 49 +/- 11%, respectively; p <0.05). A fter ergonovine administration, pacing both increased GCVF and decreas ed anterior regional coronary resistance (ACR) to a lesser extent in p atients with vasospastic angina than in control patients (GCVF, 16 +/- 4% vs 47 +/- 8%, respectively [p <0.01]; ACR, -12 +/- 3% vs -29 +/- 3 %, respectively [p <0.01]). The decreases in CDs in patients with vaso spastic angina observed after ergonovine administration were greater t han those in control patients (-18 +/- 2% vs -9 +/- 2%, respectively; p <0.05). Thus, not only epicardial, but also resistance coronary arte ries are affected by the coronary vasomotion disorder in the nonspasti c vascular bed in patients with vasospastic angina.