Atrioventricular Reentry Tachycardia

Atrioventricular reentry tachycardia (AVRT) is the second most common type of paroxysmal supraventricular tachycardia and requires an accessory pathway (AP) that bypasses conduction through the atrioventricular (AV) node. The manifestation of ventricular preexcitation in sinus rhythm with paroxysmal tachycardia is called Wolff-Parkinson-White syndrome. However, AVRT may occur in the absence of ventricular preexcitation using APs that conduct only in the retrograde direction. In the past century, we have elucidated the anatomic basis of AVRT which furthered our understanding of the mechanism and clinical implications. In the electrophysiology laboratory, often pacing maneuvers are required to differentiate atrioventricular reentry tachycardia from other forms of narrow complex tachycardia such as atrioventricular nodal reentrant, atrial, or junctional tachycardia as well as unusual AP variants. The success rate for catheter ablation is more than 90% for most accessory pathway locations and has become the first-line therapy for symptomatic patients.