ATRIAL SCAR ABLATION IN ADDITION TO PULMONARY VEIN ISOLATION FOR PERSISTENT ATRIAL FIBRILLATION: A PILOT STUDY

Abstract

Several approaches have been proposed to address the challenge of catheter ablation of persistent AF. However, the optimal ablation strategy is unknown. In this study, we sought to evaluate procedural outcomes after pulmonary vein isolation (PVI) plus low voltage area (LVA) ablation in patients with persistent AF. Methods: Consecutive patients accepted for EP study and AF catheter ablation for persistent AF were eligible for the study. High density bipolar voltage mapping data was acquired in sinus rhythm using multipolar catheters to detect LVA (defined as bipolar voltage < 0.5mV). A semi-automated software was used to ensure catheter contact and homogeneous data collection (Confidense, Biosense Webster, Inc). Patients underwent standard of care PVI followed by LVA ablation according to a standardized protocol. Results: A total of 172 patients were studied; 86 subjects undergoing PVI + LVA ablation were compared to 86 consecutive historical controls (PVI ± CFE/lines). Average age was 61 ± 9 years, 79% were male. The mean LA volume was 89 ± 25ml, LVEF 53 ± 7. Baseline characteristics were comparable). Average follow-up duration was 19 ± 7 vs 30 ±12 months in controls (P < 0.001). Freedom from AF (single procedure success) at 12 months was 72% after PVI + LVA ablation vs 53% in controls (P=0.01). Survival analysis is shown in Figure 1. Median procedure duration (300min [250,360] vs 311 (273, 376)]; P=0.05) and RF delivery (52min [43,64] vs 59 [46,76]; P=0.02) were longer in the PVI + LVA ablation group. Multivariable analysis showed that ablation strategy (PVI+LVA ablation) was an independent predictor of freedom from AT/AF (HR 0.44; 95%CI 0.25-0.71; P=0.001). There were no adverse safety outcomes associated with LVA ablation. This observational study shows that an individualized strategy of PVI + LVA ablation is associated with improved outcomes in patients with persistent AF. Adequately powered randomized clinical trials are needed to determine the role of PVI + LVA ablation for persistent AF.