High prevalence of a pathological response to acetylcholine testing in patients with stable angina pectoris and unobstructed coronary arteries. The ACOVA Study (Abnormal COronary VAsomotion in patients with stable angina and unobstructed coronary arteries).
OBJECTIVE
This study aimed at determining the prevalence of epicardial and microvascular coronary spasm in patients with anginal symptoms, despite angiographically normal coronary arteries.


BACKGROUND
Despite a typical clinical presentation with exercise-related anginal symptoms (chest pain or dyspnea) with or without occasional attacks of resting chest pain suggestive of coronary artery disease, 40% of patients undergoing diagnostic angiography have normal or "near" normal coronary arteriograms. Many of these patients are given a diagnosis of noncardiac chest pain, and some are considered to have microvascular angina. However, we speculate that abnormal coronary vasomotion (reduced vasodilatation with exercise = reduced coronary flow reserve and/or vasospasm at rest) might also represent a plausible explanation for the symptoms of the patient.


METHODS
This was a prospective study in 304 consecutive patients (50% men, mean age 66 ± 10 years) with exertional anginal symptoms undergoing diagnostic angiography. A total of 139 patients (46%) had ≥50% coronary artery disease in at least 1 coronary artery, 21 patients (7%) had luminal narrowings ranging from >20% to 49%, and 144 patients (47%) had normal coronary arteries or only minimal irregularities (<20% diameter reduction).


RESULTS
One hundred twenty-four patients of the latter (86%) underwent intracoronary acetylcholine (ACH) testing, which elicited coronary spasm in 77 patients (62%), 35 patients (45%) with epicardial spasm (≥75% diameter reduction with reproduction of the symptoms of the patient) and 42 patients (55%) with microvascular spasm (reproduction of symptoms, ischemic electrocardiographic changes, and no epicardial spasm).


CONCLUSIONS
Nearly 50% of patients undergoing diagnostic angiography for assessment of stable angina had angiographically normal or near normal coronary arteriograms. The ACH test triggered epicardial or microvascular coronary spasm in nearly two-thirds of these patients. Our results suggest that abnormal coronary vasomotion plays a pathogenic role in this setting and that the ACH test might be useful to identify patients with cardiac symptoms, despite normal coronaries. (Abnormal Coronary Vasomotion in Patients With Suspected CAD But Normal Coronary Arteries; NCT00921856).
Robert-Bosch-Krankenhaus, Department of Cardiology, Stuttgart, Germany. Peter.Ong@rbk.de
Peter
P
Ong
Anastasios
A
Athanasiadis
Gabor
G
Borgulya
Heiko
H
Mahrholdt
Juan Carlos
JC
Kaski
Udo
U
Sechtem
D000109:Acetylcholine; D000368:Aged; D000787:Angina Pectoris / Q000000981:diagnostic imaging* / Q000453:epidemiology* / Q000473:pathology; D017023:Coronary Angiography / Q000187:drug effects / Q000379:methods*; D003329:Coronary Vasospasm / Q000000981:diagnostic imaging / Q000453:epidemiology / Q000473:pathology; D003331:Coronary Vessels / Q000187:drug effects / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D011446:Prospective Studies; D014661:Vasoconstriction / Q000187:drug effects / Q000502:physiology*
D000109:Acetylcholine