The spatial distribution of atrial fibrillation termination sites in the right atrium during complex fractionated atrial electrograms-guided ablation in patients with persistent atrial fibrillation.

BACKGROUND: The role of right atrial (RA) ablation guided by complex fractionated atrial electrograms (CFAE) in atrial fibrillation (AF) has been debated. This study evaluated the spatial distribution of RA CFAE, the critical sites, and the predictors of successful termination of longstanding persistent AF during RA ablation.

METHODS: A total of 97 patients with persistent AF who received automated detection of CFAE mapping and ablation at the RA for sustained AF after pulmonary vein isolation and left atrial (LA) CFAE-guided ablation were analyzed. The AF termination patterns and CFAE areas were analyzed.

RESULTS: Forty-eight (49%) patients successfully converted to atrial tachycardia (AT) or sinus rhythm (SR) during CFAE-guided ablation at the RA. Of these, 7 (15%) patients converted directly to SR, and 41 (85%) converted via AT. The crista terminalis (CT) was the most common site for AT conversion during RA CFAE ablation, followed by the RA appendage and RA septum. Patients with larger RA volumes (> 145 mm3) had lower rates of SR or AT conversion during RA CFAE ablation. Patients with AF termination during RA CFAE ablation had less late recurrence than those without AF termination (P = 0.003).

CONCLUSION: A half of patients with persistent AF refractory to LA ablation successfully converted to AT or SR during automated CFAE-guided ablation at the RA. The most common critical sites for AF termination were the CT and RA appendage and septum. Patients with AF termination during procedure whether LA CFAE only or after RA CFAE ablation had better outcome with less late recurrence of atrial tachyarrhythmia compared to those without AF termination.