Electrogram Morphology Recurrence for Mapping Persistent Atrial Fibrillation: Initial vs Redo Catheter Ablation.

EMR identified the shortest CL sites in the PVs in 59% of patients undergoing initial persistent AF ablation, consistent with reported success rates of ∼50% for PV isolation. The majority of sites have low recurrence and may reflect bystander sites not critical for maintaining AF. EMR provides a robust new method for quantifying consistency and rapidity of activation direction at multiple atrial sites.