Coronary Vasomotor Disorders: Focus for Internists

BACKGROUND: Coronary vasomotor disorders encompass a spectrum of functional and structural abnormalities involving both the epicardial coronary arteries and the coronary microcirculation. Epicardial coronary vasospasm, coronary microvascular dysfunction (CMD) and microvascular spasm may cause myocardial ischemia in the absence of obstructive coronary artery disease (CAD) and represent an important, under-recognized, diagnostic challenge in internal medicine. PURPOSE: This review aims to provide a practical, clinically oriented framework for internists to recognize coronary vasomotor disorders in patients presenting with chest pain or myocardial injury in the absence of obstructive CAD. CONTENT: Coronary vasomotor disorders may manifest as chronic coronary syndromes, including angina with non-obstructive CAD (ANOCA) and ischemia with non-obstructive CAD (INOCA), or as acute coronary syndromes with myocardial injury and non-obstructive CAD (MINOCA). Their clinical presentation is heterogeneous and may differ from the classical pattern of classic, effort-related angina. Rest or nocturnal/early-morning chest pain, prolonged or fluctuating symptoms, incomplete response to nitrates, dyspnea, fatigue, weakness and reduced exercise tolerance should raise suspicion, particularly in women when coronary computed tomography angiography or invasive angiography demonstrate non-obstructive CAD. Non-invasive investigations may provide evidence of ischemia or CMD but may have limited ability to identify transient coronary vasomotor abnormalities, particularly epicardial or microvascular spasm. Accordingly, selected patients should undergo invasive coronary functional assessment combining coronary physiology with acetylcholine provocation testing to identify the underlying endotype. CONCLUSIONS: Coronary vasomotor disorders, including epicardial vasospasm, coronary microvascular dysfunction and microvascular spasm, are important causes of myocardial ischemia in the absence of obstructive CAD. They may present as chronic or acute coronary syndromes and are frequently underdiagnosed, leading to impaired quality of life and increased cardiovascular risk. Appropriate invasive and non-invasive testing is essential to identify the underlying endotype and guide targeted treatment.