Physical counterpressure maneuvers reduced vasovagal syncope

摘要

Fainting is most commonly the result of a vasovagal (neurocardiogenic)nreflex that causes bradycardia and peripheral vasodilation. Treatmentsnfocused on the bradycardia (e.g., pacemakers) have proven ineffective innrigorous studies (1). Treatments designed to counteract the peripheralnvasodilation (e.g., high-salt diets, mineralocorticoids, and α-agonists)nare potentially harmful, bothersome, unproven, and inefficient (requiringndaily intervention for an infrequent event). β-blockers were considerednpromising because they were thought to block the afferentnstimulus for the vasovagal reflex, but they have proven ineffective innplacebo-controlled trials (2).