Effect of Repeated Radiofrequency Catheter Ablation on Left Atrial Function for the Treatment of Atrial Fibrillation

Abstract

Radiofrequency catheter ablation (RFCA) is a potential curative treatment for atrial fibrillation (AF) by eliminating the arrhythmia and inducing left atrial (LA) reverse remodeling. However, the effect on LA function, especially after repeated procedures, has scarcely been studied. The aim of this study was to evaluate the impact of RFCA on LA size and function in patients with AF after a first and a repeated procedure. RFCA was performed in 154 patients with symptomatic drug-refractory AF. LA volumes and function were assessed with real-time 3-dimensional echocardiography before and 6 months after the procedure. Recurrence of the arrhythmia was defined as any atrial tachyarrhythmia lasting >30 seconds, clinically documented or by 24-hour Holter recording, after the first 6 months after ablation. Of the 154 patients, 104 (67%) required only a first ablation, and 50 (33%) required redo RFCA. LA volume was reduced after first RFCA (from 60 ± 19 to 52 ± 17 ml for 3-dimensional LA maximum volume, p <0.001, and from 38 ± 18 to 33 ± 15 ml for 3-dimensional LA minimum volume, p <0.000) without impairment of LA contractile function, measured as the active emptying percentage of total volume (39 ± 25% vs 43 ± 26%, p = NS). After repeated RFCA procedures, 3-dimensional LA maximum volume was reduced (from 57 ± 18 to 52 ± 18 ml, p = 0.04), also without further LA contractile function impairment (active emptying percentage of total volume) (36 ± 24% vs 36 ± 25% of total volume, p = NS). This effect was similar in paroxysmal and persistent AF. In conclusion, RFCA induces reductions in LA volumes without a deleterious impact on contractile function, even after repeated ablation.