Successful Ablation of Atypical Atrioventricular Nodal Reentrant Tachycardia From a Noncoronary Sinus of Valsalva

An 81-year-old man with long RP narrow QRS tachycardia underwent catheter ablation. Ventricular pacing reset the atrial cycle over a retrograde slow pathway, followed by termination of the tachycardia without atrial capture, confi rming the diagnosis of fast-slow atrioventricular nodal reentrant tachycardia (AVNRT). The earliest atrial activation during tachycardia was found in the noncoronary sinus of Valsalva, where the fi rst delivery of radiofrequency energy terminated and eliminated the inducibility of the tachycardia, by retrograde conduction block over the slow pathway. This is the fi rst report of a fast-slow AVNRT, with successful ablation of the slow pathway from a noncoronary sinus of Valsalva. (Int Heart J 2014; 55: 84-86)