Associations between renal function, atrial substrate properties and outcome of catheter ablation in patients with paroxysmal atrial fibrillation

Background: Renal dysfunction was reported to be associated with a higher recurrence rate after electric cardioversion of atrial fibrillation (AF). The aim of this study was to investigate the associations between renal function, atrial substrate properties and outcome of catheter ablation in paroxysmal AF patients. Methods and Results: A total of 232 paroxysmal AF patients that underwent catheter ablation were enrolled in the study. The estimated glomerular filtration rate (GFR) was calculated using the Cockcroft-Gaut equation normalized by the body surface area, and the patients were divided into 3 groups according to their GFR (group 1: ≥90 ml · min ^-1 · 1.73 m ^-2, group 2: 60-90 ml · min ^-1 · 1.73 m ^-2 and group 3: <60 ml · min ^-1 · 1.73 m ^-2). The left atrial (LA) voltage became lower and the activation time longer when the GFR decreased from group 1 to group 3. During a follow up of 25.4±13.3 months, 15.9% of the study population suffered from AF recurrences. The recurrence rates of those 3 groups were 6.9%, 14.5% and 38.9%, respectively. The LA dimension, LA voltage and groups of renal function were identified to be the independent predictors of an AF recurrence in the multivariate analysis. Conclusions: A decreased GFR was associated with an abnormal LA substrate and high recurrence rate of catheter ablation in patients with paroxysmal AF.