Head-upright tilt table testing in evaluation of recurrent, unexplained syncope.

Recurrent syncope is one of the most common problems referred to the pediatric neurologist for evaluation. Traditional evaluations are time consuming and expensive, and leave 40% of patients without a precise diagnosis. Vasovagal syncope has been believed to be a common cause of syncope; however, no reliable diagnostic modality has been available to confirm this theory. Head-upright tilt table testing has recently emerged as a useful tool in the evaluation and management of recurrent, unexplained syncope. In this review, we present the pathophysiologic mechanisms of vasovagal syncope and relate them to the reflexes triggered during head-upright tilt table testing. Additionally, we review the clinical data on the uses of this test in unexplained syncope, suggest a practical testing protocol, and elaborate potential therapeutic modalities that can be employed to prevent further episodes. Head-upright tilt table testing will likely become a standard test employed by both adult and child neurologists.