Right Atrial Continuous Fractionated Electrograms in Patients with Long-Standing Persistent Atrial Fibrillation

Hypothesis: Continuous fractionated electrograms of the right atrium (RA-CFE) before ablation can predict clinical outcome of biatrial ablation. Methods: Consecutive 122 patients (56 ±9 years, 84% male) with longstanding persistent atrial fibrillation (AF) were enrolled. Catheter ablation at left atrium (LA) including electrical isolation of 4 pulmonary vein was performed in 70 patients (LA ablation), and electrograms-guided ablation at RA was performed in whom AF was not terminated after LA ablation (n=52, bi-atrial ablation). RA-CFE (+) was defined by >90 fractionation without isoelectric period for 30 seconds at crista terminalis and RA septum. Results: RA-CFE (+) at baseline was observed in 41.4% of LA ablation and in 67.3% of bi-atrial ablation group (p=0.006). Conversion rate to sinus rhythm by LA ablation was significantly lower in RA-CFE (+) than in RA-CFE (-) (69.0% vs 82.9%, p<0.001). During the mean 6-month, in patients with RA-CFE (+), freedom from recurrence was significantly higher in bi-atrial ablation than in LA ablation (71.4% vs 69.0%, p=0.009). RA-CFE (+) was associated with the recurrence after biatrial ablation (HR 3.646, 95% CI 1.288-10.324, p=0.015). Conclusions: RA ablation provides an increment in efficacy among patients with longstanding persistent AF who shows continuous fractionaed electrograms in RA. RA-CFE is a good predictor in identifying whom RA ablation for longstanding persistent AF is beneficial.