Background: Radiofrequency catheter ablation (RFCA) has been increasingly used for the treatment of patients with symptomatic atrial fibrillation (AF).

Aim: To identify simple pre-procedural success predictors of RFCA in patients with AF.

Methods and Results: It comprised 294 consecutive patients (mean age 54 ± 11 years, 71% male) with symptomatic AF (28% — paroxysmal with short episodes (< 12 h); 50% — paroxysmal with episodes ≥ 12 h and < 7 days; 11.5% — persistent; 10.5% — long standing persistent), having undergone the first RFCA. Before RFCA, all patients underwent pulmonary vein (PV) anatomy imaging and echocardiographic left atrium diameter (LAD) evaluation. PV periostial or antral isolation guided by electroanatomical mapping was performed with additional lines or complex fractionated electrograms ablation (if required). Outcomes were defined as clinical success (complete or improvement) or failure. After a mean follow-up of 36.9 ± 13 months, clinical success was observed in 90.5% of patients, made up of 47.3% complete success, and 43.2% improvement. Patients with short AF episodes underwent fewer procedures (1.6 vs. 2, p = 0.026) and had the highest clinical (97.6%) and complete (63.9%) success rates. AF episodes < 12 h (p < 0.001), LAD < 4 cm (p = 0.01) and male gender (p = 0.002) independently predicted RFCA long-term clinical success. PV anatomy did not correlate with RFCA outcome. A trend was observed towards a larger number of procedures in patients with atypical PV anatomy (p = 0.059).

Conclusions: AF ablation should be performed in the early stage of AF, before structural remodelling development.