Persistent atrial fibrillation with left atrial low-voltage area: who benefit from additional modification?

Aims: The presence of low-voltage areas (LVAs) is associated with increased recurrence rate following ablation of persistent atrial fibrillation (PeAF). However, the benefit of additional LVA modification remains controversial. This substudy of the STABLE-SR-II trial aims to explore the factors that influence the benefit of additional LVA ablation for PeAF patients with LVAs.

Methods and results: In the STABLE-SR-II trial, PeAF patients with de novo ablation were randomized to receive either circumferential pulmonary vein isolation (CPVI, CPVI-alone group) or CPVI plus LVA ablation (CPVI-plus group). Patients with LVAs were included and analyzed in this substudy. The primary outcome was freedom from atrial arrhythmias 18 months after a single ablation procedure. LVAs were detected in 133 out of 276 PeAF patients (48%). Age and LVA burden were potential factors influencing the relative success of additional LVA ablation compared with CPVI alone in the univariable analysis. In multi-adjusted models, significant benefit from additional LVA ablation was found in patients aged ≥65 years [n = 50, hazard ratio (HR) 0.14, 95% confidence interval (CI) 0.02-0.83] or with LVA burden ≥ 15% (n = 18, HR 0.01, 95% CI: 0-0.44). LVA burden ≥15% was observed in 10 of 50 patients aged ≥65 years (20%) and in 8 of 83 patients aged <65 years (10%). Combined subgroup analysis demonstrated that LVA ablation was particularly beneficial for patients aged ≥65 years, regardless of LVA burden.

Conclusion: LVA ablation following CPVI may provide additional benefits for older PeAF patients (≥65 years) in the first procedure.

Clinical trial registration: NCT03448562 [CPVI Alone Versus CPVI Plus Electrophysiological Substrate Ablation in the LA During SR for the Treatment of Non-PAF (STABLE-SR_II)].