Abstract 13269: Clinical and Electrophysiological Features of New Onset Ventricular Arrythmias Following Catheter Ablation of Atrial Fibrillation

Abstract

Introduction: Data on new onset ventricular arrhythmias (VAs) following catheter ablation of atrial fibrillation (AF) is sparse. Hypothesis: We aimed to assess the incidence of new onset VA post AF RFA. Methods: We conducted a retrospective study of all patients at our institution that underwent AF ablation who also developed symptomatic high burden premature ventricular complexes (PVCs) requiring catheter ablation within 1 year of the index AF ablation procedure. All patients underwent post AF ablation monitoring with either 48 hr Holter monitors or implantable cardiac monitors. New onset VA was defined as symptomatic new onset PVC with >5% burden. Data on PVC morphology and successful ablation sites was analyzed. Results: Out of 175 patients that underwent AF ablation during the study period, 2.8 % (n=5) patients developed new onset high burden PVCs requiring catheter ablation therapy within 1 year of AF ablation. Mean age was 68.6 + 11 years and all patients were male. Mean baseline LVEF was 56 + 9.6% and mean PVC burden was 10.3 + 8.8 %. A total of 9 PVCs were mapped in 5 patients. The number of VA morphology was 1 in 2 (40%) patients, 2 in 2 (40%) and 3 in 1 (20%) patient. Site of origin for the PVCs was in the left ventricle in all patients, with majority (55%) localizing to the LV outflow tract and summit region (table). Average time from AF RFA to PVC ablation was 4 + 2.9 months. PVC ablation was successful in all patients except one where ablation was deferred due to proximity to the conduction system. Conclusions: New onset VAs following catheter ablation of AF tend to localize to the LV outflow tract and areas of bipolar voltage abnormality. Potential mechanisms of new onset PVCs could include altered sympathetic tone due to ablation of cardiac ganglia, unmasking of PVCs due to regularization of ventricular rate and withdrawal of anti-arrhythmic medications. Further prospective studies are needed to understand true incidence of new onset VAs following AF ablation.