Abstract 15433: Very Late Recurrence After Successful Ablation of Premature Ventricular Contractions in Patients Without Structural Heart Disease

Abstract

Background: Earlier studies have shown the superiority of catheter ablation over pharmacological therapy in eliminating premature ventricular contractions (PVC) in patients without structural heart disease. We investigated very late recurrences after successful PVC ablation in this cohort. Methods: Consecutive patients undergoing clinically indicated radiofrequency ablation for symptomatic idiopathic PVCs, documented by standard ECG, were included in the analysis and prospectively followed up. Those with history of structural heart disease were excluded. For all patients, 12-lead ECGs were reviewed to assess PVC morphology. During the index procedure, all PVC morphologies were targeted for ablation. Standardized RF power settings (40-50 W) were used during the procedure. Ablation was performed using 4-mm irrigated tip catheter guided by 3-D mapping system and intra-cardiac echocardiography. Patients were followed up with remote monitoring as well as ICD interrogations and office visits every 6 months for 4 years. Long-term success was defined as absence of previously targeted PVCs or any new PVC morphology on 12-lead ECG or device interrogation during all follow-up visits. Results: In total, 638 patients were included (mean age 59.2±5.6 years, 69.75% male, LVEF 54±12%). At the index ablation, PVCs were detected to be localized in the right ventricular outflow tract in 268 (42%), left ventricular outflow tract in 299 (46.8%) and multiple sites of origin in 71 (11.2%) patients. Non-inducibility was achieved in all patients at the end of the index procedure. At 4 years, 585 (91.7%) patients remained arrhythmia-free. Remaining 53 patients (8.1%) experiencing recurrence underwent repeat procedure. Median time to recurrence was 29±6.2 months. At the redo, new PVC morphologies were detected and ablated in 46/53 (86.8%) patients. One year after the repeat ablation, 50/53 (94.3%) were arrhythmia-free. Conclusion: In this prospective single-center series, very late recurrence following index PVC ablation in patients with no structural heart disease was mostly associated with new PVC morphologies that were amenable to be successfully ablated at the repeat procedure.