Syncope in the emergency department. A cardiologist's perspective.

Syncope is a common emergency department presentation. Syncope is a benign condition in many cases but has a poor prognosis in a number of cardiac disorders. An awareness of the serious conditions that may present as syncope and use of a systematic approach will yield a diagnosis for most patients; however, some patients remain without a diagnosis. Expending large amounts of resources for these patients often is unnecessary.