Accessory atrioventricular conduction syndromes: a review.

The index of suspicion for accessory atrioventricular conduction pathways must be high in patients with paroxysmal tachycardias in order to avoid overlooking subtle delta waves or short PR intervals. The existence of many different types of accessory AV conduction syndromes can make therapy difficult. Understanding the physiology of each patient's tachycardia can make successful management more rapid, and empiric therapy should not be pursued indefinitely if early drug regimens are unsuccessful. Electrophysiologic study may elucidate the mechanism of the tachycardia and simplify the selection of an ideal drug regimen.