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

ABSTRACT

BACKGROUND: The relationship between high-dominant frequency (DF) sites and low-voltage areas (LVAs) in nonparoxysmal atrial fibrillation (AF) patients still remains unknown. OBJECTIVE: This study aimed to evaluate the effect of ablation at high-DF sites overlapping with LVAs after pulmonary vein ablation (PVI) of nonparoxysmal AF. METHODS: 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). RESULTS: 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). CONCLUSIONS: High-DF sites overlapping with LVAs after the PVI may be potential selective targets for modification of atrial substrates in nonparoxysmal AF patients.