Syncope: etiology, management, and when to refer.

An abnormality of blood pressure control is by far the most likely cause of syncope in children; however, syncope in children may be due to primary cardiac dysrhythmias, particularly in the presence of structural heart disease. An appropriate work-up should include an ECG with a 60-second rhythm strip at first presentation. Tilt testing can usually wait until after a second occurrence on non-pharmacologic therapy. Patients who require more than a history and ECG by the algorithm in the Figure should probably be referred to a cardiologist familiar with the evaluation of syncope. The common form of neurally mediated syncope is also probably related to both breath-holding spells in toddlers, and to many of the cases of chronic fatigue syndrome.