Myocardial Ischaemic Syndromes: Shifting from a Coronary-centric to a Substrate-based Nomenclature is More Accurate and Inclusive

This article highlights the rationale for a more accurate and inclusive classification that does not focus solely on epicardial coronary lesions as the causa sine qua non for angina and myocardial ischaemia in all patients but rather represents a more comprehensive classification encompassing both obstructive and non-obstructive causes. Ischaemia may be ‘silent’ clinically or electrocardiographically and is observed in both acute and non-acute settings, as seen in patients with diabetes and other conditions associated with microvascular dysfunction. By pivoting away from the more restrictive and overly simplistic ‘vessel-based’ classification that disproportionately focuses on obstructed epicardial arteries to a ‘substrate-based’ nomenclature inclusive of both obstructive and non-obstructive causes, ‘myocardial ischaemic syndromes’ will better align and unify a patient-centric approach by harmonising the full spectrum of pathophysiologic causes.