Syncope: Approaches to Diagnosis and Management.

Syncope is defined as a transient loss of consciousness due to cerebral hypoperfusion followed by spontaneous recovery. Common causes of syncope include vasovagal syncope, situational syncope, orthostatic hypotension, carotid sinus hypersensitivity, left- and right-sided obstructive cardiac lesions, and cardiac arrhythmias. History and physical examination often provide valuable clues about the underlying etiology of syncope. Admission decisions in the emergency department can be guided by various risk prediction scores. Evaluation of a patient with syncope involves a large battery of diagnostic tests that include a 12-lead electrocardiogram, Holter monitoring, echocardiogram, tilt table testing, ischemia evaluation, electrophysiologic studies, and other imaging tests. Despite the availability of these advanced diagnostic tests, a significant proportion of patients with syncope remain undiagnosed. Therapy should be tailored based on the underlying etiology of syncope.