PO-681-06 ANTERO-SEPTAL FOCAL ATRIAL TACHYCARDIAS AND ATRIAL FIBRILLATION TRIGGERS FROM THE NON-CORONARY CUSP: A RARE NON-PULMONARY VEIN SOURCE OF RECURRENT ARRHYTHMIAS FOLLOWING ATRIAL FIBRILLATION ABLATION

Abstract

In patients with recurrent atrial arrhythmias following pulmonary vein isolation (PVI), focal atrial tachycardias (AT) or AF triggers from the thoracic veins, perivalvular structures or adjacent to previously ablated regions are known sources of recurrence. Antero-septal AT/AF triggers have not been previously documented as a potential mechanism of recurrent arrhythmias following PVI. To investigate the prevalence of antero-septal AT/AF triggers following PVI and describe the ablation approach and long-term outcomes. We reviewed cases of antero-septal AT/AF triggers in patients undergoing repeat catheter ablation of AT/AF following PVI. Antero-septal AT/AF triggers were identified with activation mapping from the right and left antero-septal region and non-coronary cusp (NCC). Out of 1276 consecutive patients undergoing catheter ablation of recurrent AT/AF following PVI, 14 (1%) were identified with antero-septal AT (n=9, 64%) or AF triggers (n=5, 36%) defined as focal firing inducing AF. In all cases, the activation recorded at the NCC was the earliest or simultaneous with the earliest at the right anterior septum. Catheter ablation was successfully performed from the NCC under intracardiac echocardiography (ICE) guidance in all cases (Figure). At 12 months follow-up, 12 (86%) patients were free from recurrent atrial arrhythmias. Antero-septal AT/AF triggers are a rare mechanism of atrial arrhythmia recurrence following PVI. Catheter ablation of these arrhythmias from the NCC is highly successful with good long-term arrhythmia suppression.