Impact of diagnosis-to-ablation time on left atrial remodeling and voltage-guided ablation outcome in persistent atrial fibrillation patients

Abstract

Background Delayed catheter ablation (CA) is linked to higher atrial fibrillation (AF) recurrence. Low-voltage zones (LVZs) are established predictors of AF recurrence after CA. Data on LVZ assessment in relation to diagnosis-to-ablation time (DAT) remain limited. This study aimed to evaluate left atrial (LA) LVZ extent, bipolar voltage, and outcomes of voltage-guided CA in persistent AF patients according to DAT. Methods We consecutively enrolled 350 patients with persistent AF undergoing a first voltage-guided CA. Patients were classified as DAT ≤1 year (n=131) or >1 year (n=219). LA voltage mapping was performed in sinus rhythm. LVZs were defined as bipolar voltage <0.5 mV. Results Patients with DAT >1 year had lower LA bipolar voltage (p<0.01) and larger LA and indexed LA volumes (p<0.01). LVZs were more frequent in this group (43% vs 28%, p=0.01), particularly moderate LVZs (p=0.04). Atrial tachyarrhythmias (ATs) recurrence after one procedure occurred more often in patients with DAT >1 year (log-rank p=0.05). Multivariable analysis showed female sex (p<0.001), indexed LA volume ≥48 ml/m² (p=0.008), age ≥60 years (p<0.05), and P-wave duration ≥150 ms (p<0.001) were independently associated with LVZ presence. A history of paroxysmal AF was associated with a lower likelihood of LVZ, whereas DAT was not an independent predictor. Conclusion Persistent AF patients with longer DAT displayed more extensive LA substrate remodeling. Despite a tailored ablation targeting LVZs, a longer DAT remained associated with a higher rate of ATs recurrence. Early ablation within the first year after AF diagnosis could optimize AF CA outcome.