Abstract
Background This study aimed to evaluate the relationship
between dominant frequencies (DFs)/rotors and low-voltage areas (LVAs)
using the Advisor HD grid (HDG) after pulmonary vein isolation (PVI) in
non-paroxysmal atrial fibrillation (AF).
Methods A total of 73 non-paroxysmal AF patients were
prospectively investigated. After pulmonary vein isolation (PVI), an
online real-time phase mapping system was used to detect the location of
rotors with critical non-passively activated ratios (%NPs) of≧50% in
each LA segment, and high-DFs of ≧7Hz were simultaneously mapped. After
recovering sinus rhythm, LVAs (<0.5mV) were mapped using the
HDG.
Results Sixty-eight of 73 (93.2%) AF patients had minimum to
mild LVAs (<10%) regardless of an enlarged LAD and LA volume
(45±6.1mm and 142±30ml). There were no significant differences in the
max and mean DF values and %NPs between the patients with and without
recurrent AF/AT (atrial tachycardia). However, LVAs were significantly
greater in the patients with AF/AT than in those without (6.4±8.0% vs.
2.5±2.6% P=0.003). Furthermore, the number of high-DF sites overlapping
with LVAs was significantly greater in the patients with AF/AT than in
those without (0.5±0.8 vs. 0.2±0.7, P=0.019). The AF/AT freedom off
anti-arrhythmic drugs after the PVI was significantly lower in the
patients with high-DFs sites overlapping with LVAs than in those without
during 11.6±0.8 months of follow-up (35.7% vs. 69.5%, p=0.021).
Conclusions High-DF sites overlapping with LVAs detected
accurately by the HDG, regardless of whether a minimum to mild extent,
might be more selective targets after a PVI in non-paroxysmal AF
patients.
Key words: atrial fibrillation; catheter ablation; dominant
frequencies; low-voltage areas; pulmonary vein isolation; rotors.