Local abnormal atrial activity related to right septal intra-atrial reentrant tachycardia after mitral valve surgery

Substrate-based catheter ablation (CA) during sinus rhythm has been recently reported as a useful therapeutic option for patients with either atrial1,2 or ventricular3,4 tachyarrhythmias. As a therapeutic target for ventricular tachycardia (VT), elimination of local abnormal ventricular activities (LAVAs) during sinus rhythm or ventricular pacing has been reported to be a useful and effective endpoint for substrate-based VT ablation.5 However, there are limited published reports regarding local abnormal activity with a decremental property in the field of atrial tachycardia (AT). Herein, we report a patient with local abnormal atrial activity (LAATA)-related intra-atrial reentrant tachycardia (IART) recorded at the posterior septum of the right atrium (RA), which was located at the opposite side of a prior direct left atriotomy incision.