Predictors of recurrence of paroxysmal atrial fibrillation after REDO ablation procedures using an automated lesion tagging system

Aims: To evaluate the long-term outcome of patients with paroxysmal atrial fibrillation (AF) undergoing REDO ablation procedures with an automated ablation tagging module (VISITAG), and to define the major predictors of AF recurrence. Methods: Fifty-three patients with symptomatic paroxysmal AF undergoing REDO ablation procedures with VISITAG were enrolled. In every patient, the technique used during the first ablation procedure was evaluated, including the previous use of VISITAG. Patients were followed-up for a mean of 15±6 months and the main predictors of AF recurrence among clinical, cardiac functional, and procedural variables were individuated. To provide a comparison, a matched group of historical patients who underwent REDO AF ablation procedures without VISITAG was also selected. Results: The average age of the population was 61±9 years, with a higher prevalence of men over women (41 vs 12 patients, respectively). The majority of the patients presented left atrial dilatation (68%) and preserved left ventricle ejection fraction (mean 60±4%) on echocardiography. In 24 (45%) patients VISITAG was already used during the first ablation procedure. After REDO ablation 35 patients (66%) were free from AF recurrence at the last available follow-up. The long-term recurrence rate of AF was numerically higher in patients ablated with VISITAG during the first procedure than in the rest of the population (50% vs 21%; P=0.024). However, on multivariate Cox regression analysis, female gender (HR: 6.17; 95% CI: 1.60-23.73; P=0.008) and left atrial dilatation (HR: 9.47; 95% CI: 1.23-72.75; P=0.031) resulted the only independent predictors of long-term AF recurrence, overwhelming the effects of major clinical and procedural data. The success rate of REDO ablation procedures of the study population was not significantly different from that of the historical cohort (P=0.932). Conclusions: Female gender and left atrial dilatation are the most powerful predictors of AF recurrence after REDO ablation procedures. No significant impact of major procedural data was detected, with limited additional benefit coming from the use of dedicated ablation VISITAG tagging module