Unexplained syncope: clinical management.

The management of unexplained syncope begins with the patient's history and physical examination, which are oriented to help separate benign from serious causes. Malignant etiologies are more likely to occur with exertional syncope. Cardiac causes should be considered, particularly cardiomyopathy, postoperative congenital heart disease, right ventricular dysplasia, anomalous coronary artery, pulmonary artery hypertension, myocarditis, long QT syndrome, and Wolff-Parkinson-White syndrome. Neurological and metabolic disorders may underlie a syncope episode. After malignant causes of syncope have been excluded and the diagnosis of neurocardiac syncope has been established, treatment strategies include behavior modification, salt and increased fluids, and pharmacological agents. Efficacious agents include beta-blockers, dysopyramide, fludrocortisones, and alpha agents. Yet, behavior modification alone may be as effective as salt or pharmacological therapy. Because the natural history of neurocardiac syncope in children is spontaneous resolution, it is appropriate to try the simple measures before introducing drug therapy.