Syncope and seizures of psychogenic origin: identification with head-upright tilt table testing.

Psychogenic seizures and psychogenic syncope are common disorders but are difficult to identify. Head-upright tilt table testing has emerged as a promising means of evaluating vasovagally mediated syncope and convulsive syncope. Of a total of 42 patients evaluated by head-up tilt for recurrent syncope and 10 evaluated for recurrent idiopathic seizures, a total of 5 patients experienced syncope and 3 had tonic-clonic seizure activity unaccompanied by any significant changes in blood pressure, heart rate, transcranial Doppler cerebral blood flow velocity, and electroencephalographic monitoring. Psychiatric evaluation revealed that seven patients suffered from conversion reactions and one from probable malingering. We conclude that patients who pass out or convulse during head-upright tilt without any change in physiologic parameters can be presumed psychogenic in origin and may be referred for psychiatric evaluation without further expensive diagnostic studies.