Repeated catheter ablation of atrial fibrillation: how to predict outcome?

Background: Pre-procedural predictors (PP) of atrial fibrillation (AF) recurrence (AFR) after repeated catheter ablation of AF (RCAF) are unknown. The aim of this study was identification of PP of outcome after RCAF.
Methods and Results: In 213 patients (73% male) with drug-refractory AF (47% paroxysmal AF; PAF) RCAF was performed. CHADS2, CHA2DS2-VASc and ALARMEc (AF type, Left Atrium size, Renal insufficiency, MEtabolic syndrome, cardiomyopathy) scores were calculated for each patient. Complete success was defined as no AFR. After RCAF, 125 patients (59%) were free of atrial flutter or atrial tachycardia (AFLAT) on long-term follow-up (FU). The univariate predictors of AFR were: type of AF (non-PAF vs. PAF, P=0.001), normalized left atrium area (NLA ≥10.25 vs. NLA <10.25, P=0.012) and estimated glomerular filtration rate (<68ml/min vs. ≥68ml/min, P=0.048). The independent predictors of AFLAT-free survival after RCAF were non-PAF (P=0.002) and NLA ≥10.25 (P=0.018). Among combined predictors, only ALARMEc score, and neither CHADS2 or CHA2DS2-VASc, predicted outcome after RCAF (P<0.0001).
Conclusions: RCAF results in a moderate success rate on very long-term FU. Lower success was observed in patients with non-PAF and enlarged LA. ALARMEc score allows for clear description of expected outcome after RCAF.