Intracoronary acetylcholine for vasospasm provocation in women with ischemia and no obstructive coronary artery disease

Abstract

Objectives: To evaluate the utility of higher dose intracoronary acetylcholine (ACh) during invasive coronary function testing (CFT) in women with suspected ischemia and no obstructive coronary artery disease (INOCA) for detection of epicardial vasospasm, relation to quality of life (QoL) and the presence of scar by late gadolinium enhancement (LGE) on cardiac magnetic resonance imaging (CMRI).

Background: CFT is an established method for diagnosis of coronary microvascular dysfunction (CMD). The utility of epicardial vasospasm provocation testing with higher dose ACh infusion is not fully understood.

Methods: Women with suspected INOCA undergoing invasive CFT were enrolled in the Women's Ischemia Syndrome Evaluation-Pre-Heart Failure with Preserved Ejection Fraction (WISE Pre-HFpEF) study (NCT03876223). Incremental infusions of 0.364, 36.4 μg and 108 μg ACh were used for vasospasm provocation. Vasospasm was defined as ≥75 % artery diameter reduction compared to post-nitroglycerin diameter and related to QoL and LGE on CMRI.

Results: Among 73 women (56 ± 11 years), epicardial vasospasm was detected in 17 (23 %). Among women with vasospasm, the vast majority (94 %) had coronary endothelial dysfunction and few (12 %) had other abnormal CFT measures. Those with vasospasm had more nocturnal angina symptoms, calcium channel blocker use, poorer QoL (all p = 0.001) and disease perception (p = 0.02) than those without. LGE scar by CMRI was not associated with vasospasm (p = 0.22).

Conclusions: Among women with suspected INOCA, intracoronary Ach spasm testing provoked epicardial vasospasm in one fourth. Women with epicardial vasospasm overwhelmingly had concomitant endothelial dysfunction, worse QoL but not more frequent myocardial scar on CMRI.