Low Voltage Areas in the Left Atrium After Sole Pulmonary Vein Isolation as a Predictor of Atrial Fibrillation Recurrence-Based on Sequential Voltage Map Analysis Using High-Density Mapping Catheters.
BACKGROUND: Low-voltage areas (LVA) in the left atrium (LA) have been linked to atrial fibrillation (AF) recurrence. However, prior studies lacked high-density mapping catheter (HMDC) mapping, included non-pulmonary vein isolation (PVI) ablation strategies, and did not follow temporal progression of LVA in individuals. METHODS AND RESULTS: We retrospectively analyzed 1661 AF patients who had undergone initial ablation using PVI alone, and in whom voltage maps of the LA had been created with HDMCs. We investigated the relationship between LVA size (Small-LVA group: LVA < 5 cm2 and Extensive-LVA group: LVA ≥ 5 cm2) and AF recurrence. HDMCs were again used to map the LA at the time of the re-do ablation. A total of 711 patients met our inclusion criteria (Small-LVA 554, Extensive-LVA 157). During the mean follow-up period of 643.6 ± 490.5 days, 21% of Small-LVA patients (n = 117) and 33% of Extensive-LVA patients (n = 52) experienced recurrence (p < 0.005), of whom 106 (63%) underwent redo ablation. Belonging to the Extensive-LVA group was predictive of AF recurrence both after the initial ablation and after the redo ablation. They also exhibited greater non-PV related recurrence. Time-dependent progression of LVA was observed in 32 patients with a mean increase of 4.7 ± 5.1 cm2 and was significantly more frequent in the Extensive-LVA group. This progression was not linked to AF recurrence. CONCLUSION: We used high-density mapping to evaluate left atrial LVA in patients who had only received PVI, and demonstrated LVA influence on AF recurrence and recurrence patterns.