Need to know:

Ischaemic heart disease is a major cause of morbidity and mortality, and coronary atherosclerosis is a well-recognised cause.

However, ischaemia with no obstructive coronary artery disease (INOCA) may be the culprit for those with angina symptoms and no obstructive coronary lesions on imaging. INOCA has been an under-recognised problem with multiple potential aetiologies.¹ Accordingly, the 2021 ACC/AHA chest pain guidelines redefined coronary disease to include any degree of coronary stenosis, including INOCA.²

INOCA encompasses coronary vasomotion disorders, including coronary vasospasm, microvascular angina and microvascular spasm. These may be underdiagnosed because traditional coronary angiography alone does not visualise the microcirculation or assess vasomotor function.