Exercise-Associated Syncope: A Narrative Review of Pathophysiology, Clinical Classification, and the Diagnostic Role of the Head-Up Tilt Test.

Syncope is a common clinical condition characterized by a transient loss of consciousness caused by temporary global cerebral hypoperfusion. Exercise-associated syncope is clinically important because it may reflect benign physiological mechanisms or represent the initial manifestation of a potentially life-threatening cardiovascular disorder. This narrative review examines current evidence on its epidemiology, pathophysiology, classification, diagnostic evaluation, differential diagnosis, and management. The reviewed evidence indicates that syncope occurring during exercise should be considered a high-risk presentation requiring prompt cardiovascular evaluation, whereas post-exercise episodes are more frequently associated with reflex mechanisms and impaired venous return. Initial assessment should include a detailed history, physical examination, orthostatic blood pressure measurement, and 12-lead electrocardiography, with echocardiography, exercise testing, ambulatory rhythm monitoring, or head-up tilt testing selected according to the suspected mechanism. Head-up tilt testing is most useful when reflex syncope remains suspected after the initial evaluation. A structured, risk-based diagnostic approach is therefore recommended to identify cardiac causes early while avoiding unnecessary testing in patients with likely benign syncope.