Atrioventricular Nodal Reentrant Tachycardia

A 32-year-old female presented with recurrent narrow complex tachycardia. She had undergone three prior ablations for typical AVNRT. AVNRT was inducible at EP study. Ablation at the typical anatomic site of the slow pathway failed to abolish slow pathway conduction. Entrainment maneuvers suggested a leftward extension of the slow pathway. Ablation of the slow pathway was successful via transseptal approach.