Extensive left atrial low-voltage area during initial ablation is associated with a poor clinical outcome even following multiple procedures.

Introduction Some patients fail to respond to persistent atrial fibrillation (PeAF) catheter ablation in spite of multiple procedures and ablation strategies, including low voltage area (LVA)-guided, linear, and complex fractionated atrial electrogram (CFAE)-guided ablation procedures. We hypothesized that LVA extent could predict non-response to PeAF catheter ablation in spite of multiple procedures. Methods This study included 510 patients undergoing initial ablation procedures for PeAF. LVAs were defined as regions with bipolar peak-to-peak voltages of <0.50 mV after PVI during sinus rhythm. Patients were categorized by LVA size into groups A (0-5 cm2), B (5-20 cm2), and C (over 20 cm2). The primary endpoint was AF-free survival after the last procedure. Results During a median follow-up of 25 (17, 36) months, AF recurrence was observed in 101 (20%) patients after 1.4±0.6 ablation procedures (maximum 4). A Kaplan-Meier analysis showed the AF-free survival rate significantly differed by LVA size. Conclusion Extensive LVA after initial PVI was associated with a poor clinical outcome even following multiple procedures.