Cardiovascular syncope: Diagnostic approach and risk assessment

Cardiovascular syncope, defined as a transient loss of consciousness resulting from a global cerebral hypoperfusion characterized by rapid onset and spontaneous rapid recovery, comprises events due to bradyarrhythmias, tachyarrhythmias, and structural cardiovascular disease. The evaluation of cardiovascular syncope must be careful and thorough as this type of syncope is associated with increased subsequent morbidity and mortality. In this review we provide current data regarding specific causes of cardiovascular syncope, diagnostic approach, risk stratification, and management of patients who experience a syncope event when a cardiovascular disorder is suspected to be a precipitating factor for the syncope event. Multiple risk stratifications studies were carried out to identify patients at high risk for cardiovascular syncope; we provide several prominent examples of such risk stratifications, with special focus on the congenital long QT syndrome (LQTS) as an example of an arrhythmogenic disorder associated with syncope and sudden cardiac death in young individuals without structural heart disease.