The medical therapy of cardioinhibitory syncope in pediatric patients.

A small percentage of pediatric patients with neurally mediated syncope will have an asystolic response during upright tilt table testing. The purpose of this study is to evaluate the incidence of asystole during tilt table testing, and to assess the outcome of medical management of such patients. Of 398 patients undergoing evaluation for recurrent syncope between January 1989 and 1994, 18 (4.5%) experienced asystole lasting > or = 5 seconds during baseline tilt test. Patients had experienced a mean of four episodes of syncope, with a mean age at the time of tilt test of 11.1 +/- 4.0 years. The median duration of asystole was 10 seconds (range 5-40 s). Treatment was individualized to increased fluids and salt intake (3 patients), metoprolol (8 patients), pseudoephedrine (4 patients), disopyramide (1 patient), or combination therapy with fludrohydrocortisone (2 patients). During a median duration of follow-up of 31 months, no additional syncope was experienced by 78% of patients. Recurrent syncope in 4 patients was associated with either noncompliance or discontinuation of therapy in 3 patients; in 1 patient, increasing the dose of metoprolol was effective in preventing recurrences. We conclude that young patients with recurrent syncope and asystole during tilt test may be safely and effectively managed with pharmacological therapy, without resorting to pacemaker implantation.