Occurrence of atrial tachycardia during catheter ablation of persistent atrial fibrillation and low-voltage areas: a significant surrogate of arrhythmia recurrence

Low voltage areas (LVAs) can serve as substrates for slow conduction, potentially leading to the induction of atrial tachycardia (AT) during atrial fibrillation (AF) ablation. However, patient characteristics associated with AT occurrence and its impact on post-ablation recurrence remain unclear.

This study aimed to identify patient characteristics associated with AT occurrence during initial catheter ablation and evaluates its impact on post-ablation recurrence in persistent AF patients with LVAs.

An analysis was performed from the SUPPRESS-AF trial, a randomized controlled trial that investigated the efficacy and safety of LVA ablation in patients with persistent AF and LVAs. AT was induced by burst pacing after pulmonary vein isolation with or without LVA ablation. All induced ATs were ablated until non-inducibility.

Of 339 study patients, 48 ATs (9 peri-mitral flutters, 6 roof-dependent ATs, 33 other ATs) were induced and ablated in 38 (11.2%) patients. Patients with induced ATs were more likely to be female (73.7% vs. 46.2%, p=0.001), had larger LVAs (20.8 vs. 12.8 cm2, p<0.001), and more frequently underwent LVA ablation (68.4% vs. 47.2%, p=0.014) than those without induced ATs. Despite a high success rate of AT ablation (78.9%; 30/38 patients), subsequent AF/AT recurrence rates were significantly higher in patients with induced AT compared to those without (52.6% vs. 36.5%, log-rank p=0.040) (Figure). Multivariate Cox regression analysis revealed that AT occurrence was independently associated with subsequent recurrence after adjusting for age, sex, left atrial diameter, the extent of LVAs, non-PV trigger ablation, and LVA ablation (hazard ratio, 1.94; 95% confidence interval, 1.15–3.10; p=0.014) (Table).

In persistent AF patients with LVAs, AT was more frequently induced in females, those with larger LVAs, and those undergoing LVA ablation. AT occurrence was an independent predictor of post-ablation recurrence.

Kaplan-Meier curve