Comparison of Intracoronary Injection of Acetylcholine and Ergonovine in All Vessel Segments in Patients with and without Vasospastic Angina Pectoris
To compare the effects of provocative agents on coronary vascular tone, we performed intracoronary injections of acetylcholine (ACh) and ergonovine (EM) in 12 patients with vasospastic angina pectoris (VSA) and in 11 patients without coronary artery disease (control group). Incremental doses of ACh (20–100μg) were injected, followed by EM (20–50 μg) after the disappearance of ACh action. The reduction ratio of coronary artery diameter (RR-CAD), (1-after ACh or EM CAD/after isosorbide dinitrate (ISDN CAD) × 100(%), was calculated in every AHA segment. In patients with VSA, coronary spasms (RR-CAD > 99%) were induced by ACh in 10/12 patients, by EM in 10/12, and by both agents in 8/12 in the same segment, whereas in the control group, spasms were induced only by ACh, in 1 of 11 patients, and chest pain was not experienced. Responses to ACh and EM in each AHA segment in the VSA group, except in spasm-induced sites, tended to be greater than in the control group, i.e., RR-CAD values (mean ± SEM) including all American Heart Association (AHA) segments following ACh and EM administration were 47.0 ± 7.1% and 50.8 ± 6.8% respectively, in the VSA group and 35.8 ± 7.8% and 40.7 ± 5.0% respectively, in the control group. We conclude that the sensitivity to ACh and EM challenge was the same, but that both agents were needed to achieve more accurate diagnosis.