5978Critical role of non-pulmonary vein triggers in patients with atrial fibrillation referred after two or more failed catheter ablations

Background: Atrial fibrillation (AF) begins as a pulmonary vein (PV)-trigger based arrhythmia, but maintenance of AF is mostly seen to be driven by ectopic triggers in the non-PV foci. Objective: We report the procedural findings and ablation outcome in consecutive AF patients referred to our center after two or more ablation procedures Methods: Three hundred five consecutive patients [paroxysmal AF 82 (27%)] referred to our institutions from January 2009 to August 2015, after ≥2 failed procedures at other centers, were included in this analysis. High-dose isoproterenol challenge was used to identify non-PV triggers. These were defined as ectopic triggers originating from sites such as interatrial septum (IAS), left atrial appendage (LAA), crista terminalis (CT), superior vena cava (SVC) and coronary sinus (CS). Both sustained (>30 seconds) as well as non-sustained triggers including repetitive short- lasting bursts of arrhythmia (<30 sec) or premature atrial contractions (PAC) (≥10 beats/minute) with earliest activation from non-PV sites were targeted for ablation. Patients were monitored for arrhythmia at quarterly office visits, ECGs, 7-day holter monitoring and event recorders. Any episode of AF/AFL/AT >30 sec occurring after the 90-days' blanking period were considered as recurrence.