Treatment of advanced atrioventricular block with beta-adrenergic blockade therapy

A 26-year old woman, who experienced syncope associated with advanced AV block, was referred for further evaluation. Electrophysiological study showed normal SA and AV node physiology. Syncope associated with advanced AV block on the electrocardiogram was induced by head-up tilt test. Oral propranolol therapy completely prevented the AV block and syncope induced by head-up tilt. The physician should be aware of advanced AV block associated with neurocardiogenic syncope, especially before permanent - pacemaker therapy is considered. The head-up tilt test is a useful diagnostic tool for an etiology of paroxysmal AV block.