Pathophysiology and differential diagnosis of neurocardiogenic syncope

Syncope, the transient loss of consciousness and postural tone, is both a s ign and a syndrome and may result from very diverse causes. Over the last d ecade, considerable attention has been focused on neurocardiogenic syncope, also known as vasovagal syncope. Research hers demonstrated that the disor der is one aspect of a much broader group of disturbances of the autonomic nervous system that may lead to hypotension, orthostatic intolerance, and u ltimately syncope. Recent discoveries have caused us to reevaluate our clas sification of autonomic disorders and to develop a new system that reflects current knowledge. A basic understanding of syncope and related disorders is essential to diagnosis and proper treatment. This article provides an ov erview of these conditions, their pathophysiology, and diagnosis. (C) 1999 by Excerpta Medico, Inc.