Effect of ablation at high-dominant frequency sites overlapping with low-voltage areas after pulmonary vein isolation of nonparoxysmal atrial fibrillation.

Abstract

The relationship between high-dominant frequency (DF) sites and low-voltage areas (LVAs) in nonparoxysmal atrial fibrillation (AF) patients still remains unknown. This study aimed to evaluate the effect of ablation at high-DF sites overlapping with LVAs after pulmonary vein ablation (PVI) of nonparoxysmal AF. A total of 128 consecutive nonparoxysmal patients with atrial fibrillation (53 persistent AF) were retrospectively investigated. The patients with AF were divided into two groups: patients with circumferential PVI alone (PVI group, n = 57) and those with PVI followed by a DF-based ablation (DF group, n = 71). The patient characteristics did not significantly differ between the two groups. However, the LVA ( < 0.5 mV)/left atrial (LA) surface was significantly greater in the DF than the PVI group (22% vs 16%, P = .02). The total max-DF sites overlapping with LVAs in the LA were significantly greater in the DF than the PVI group (91% vs 10%, P = .001). The atrial arrhythmia freedom on antiarrhythmic drugs in the DF group was significantly greater than that in the PVI group during 10.0 ± 3.2 months of follow-up (83.1% vs 64.9%, log-rank test P = .021). The event-free survival in the PVI group decreased according to the LVA extent while it was > 80% in the DF group. The event-free survival in patients with AF especially with extensive LVAs ( ≥ 30%) in the DF group was significantly greater than that in the PVI group (81.0% vs 45.5%, log-rank test P = .035). High-DF sites overlapping with LVAs after the PVI may be potential selective targets for modification of atrial substrates in nonparoxysmal AF patients.