Low-voltage-area ablation in paroxysmal atrial fibrillation: Extended
follow-up results of the VOLCANO trial
Abstract
Introduction: The randomized controlled VOLCANO trial demonstrated
comparable 1-year rhythm outcomes between patients with and without
ablation targeting low-voltage areas (LVAs) in addition to pulmonary
vein isolation among paroxysmal atrial fibrillation (AF) patients with
LVAs. To compare long-term AF/atrial tachycardia (AT) recurrence rates
and types of recurrent-atrial-tachyarrhythmia between treatment cohorts
during a > 2-year follow-up period. Methods: An
extended-follow-up study of 402 patients enrolled in the VOLCANO trial
with paroxysmal AF, divided into 4 groups based on the results of
voltage mapping: Group A, no LVA (n=336); group B, LVA ablation (n=30);
group C, LVA presence without ablation (n=32); and group D, incomplete
voltage map (n=4). Results: At 25 (23, 31) months after the initial
ablation, AF/AT recurrence rates were 19% in group A, 57% in group B,
59% in group C, and 100% in group D. Recurrence rates were higher in
patients with LVAs than those without (group A vs. B+C,
p<0.0001), and were comparable between those with and without
LVA ablation (group B vs. C, p=0.83). Among patients who underwent
repeat ablation, ATs were more frequently observed in patients with LVAs
(Group B+C, 50% vs. A, 14%, p<0.0001). In addition, LVA
ablation increased the incidence of AT development (group B, 71% vs. C,
32%, p<0.0001), especially biatrial tachycardia (20% vs.
0%, p=0.01). Conclusion: Patients with LVAs demonstrated poor long-term
rhythm outcomes irrespective of LVA ablation. ATs were frequently
observed in patients with LVAs, and LVA ablation might exacerbate
iatrogenic ATs.