Acetylcholine Provocation Testing for Coronary Vasomotor Disorders

Vasospastic angina and microvascular angina are increasingly recognized as important causes of myocardial ischemia in patients with angina or myocardial infarction and non-obstructive coronary arteries (ANOCA/MINOCA). Unlike obstructive coronary artery disease, these conditions result from dynamic alterations in epicardial and/or microvascular tone that are not detected by standard coronary angiography. Intracoronary acetylcholine (ACh) provocation testing enables direct assessment of coronary vasomotor function by evaluating both endothelial integrity and smooth muscle reactivity. Moreover, ACh can identify epicardial spasm, microvascular spasm, or impaired endothelium-dependent vasodilation, thereby providing precise characterization of the underlying pathophysiological mechanism. When performed using standardized protocols, ACh testing has shown a high diagnostic yield and a reassuring safety profile. In addition to the associated diagnostic relevance, the ACh response carries prognostic significance, as abnormal findings are associated with a higher risk of recurrent angina and adverse cardiovascular events. Furthermore, randomized data demonstrated that treatment tailored to invasive coronary function testing improves symptoms and quality of life. This review summarizes the pathophysiological background, practical aspects, safety, and clinical value of ACh provocation testing, underscoring its central role in a more personalized approach to patients with ANOCA/MINOCA.