Diagnosing syncope. With an emphasis on cardiac causes.

Evaluation of syncope may be lengthy and expensive, and, in up to 50% of patients, will not produce a diagnosis. If a definite cause is found, specific therapy may offer symptomatic relief, although the patient's prognosis depends primarily on the nature and severity of any underlying disease. A patient with no evidence of organic heart disease for whom a complete evaluation reveals no cause for syncope has an excellent prognosis, even though syncopal symptoms may recur. The initial evaluation and management of most patients with syncope can be performed by the primary care physician if facilities for Holter monitoring, echocardiography, and signal-averaged electrocardiography are available. Consultation with a cardiologist is necessary only when the results of the initial evaluation are unrevealing or if findings suggest the need for a more intensive secondary elevation.