THE ROLE OF PACING FOR THE MANAGEMENT OF NEURALLY-MEDIATED SYNCOPE - CAROTID-SINUS SYNDROME AND VASOVAGAL SYNCOPE

The role of permanent cardiac pacing for the management of neurocardio genic syncope is controversial; however, it does have a secondary role in appropriately selected individuals. Neurocardiogenic syncope inclu des vaso-vagal and enhanced antagonism of sympathetic-parasympathetic mechanisms. Differentiation of the so-called cardiac inhibitory, vasod epressor, and mixed forms of these disorders is frequently misleading when establishment of effective treatment strategies is attempted. Car diac pacing can artificially restore near-normal heart rate and atriov entricular synchrony during a neurocardiogenic syncopal episode; howev er, cardiac pacing does not alter the peripheral vasodilitation, nor d oes it prevent the occurrence of the reflux response. Syncopal patient s with carotid sinus hypersensitivity or vasovagal responses that incl ude marked bradycardia and loss of atrioventricular synchrony can be s upported by dual-chamber cardiac pacing in combination with other ther apeutic interventions that diminish the severity of the reflex respons e. The conditions of patients with carotid sinus syndrome and carotid sinus hypersensitivity are frequently improved with cardiac pacing, an d the conditions of elderly patients with vasovagal syncopy are common ly improved with artificial pacing. The classic younger patient with m alignant vasovagal syncope derives less benefit from artificial pacing ; however, in carefully selected persons dual-chamber pacing combined with drug therapy and education decreases syncopal episodes and permit s a return to normal activities.