Scenes from a CFAE: Complex Fractionated Atrial Electrogram Map in a Woman with Longstanding Persistent Atrial Fibrillation Following Mechanical Mitral Valve Replacement.

Case: A 62-year-old woman was referred for atrial fibrillation (AF) ablation. She had longstanding persistent AF for 8 years since mechanical mitral valve replacement for rheumatic heart disease. EPS: A strategy of substrate-based ablation targeting areas of complex fractionated atrial electrograms (CFAE) was pursued. These sites were identified by inspection of electrograms and verified with software-based electrogram analysis, with the left atrial roof demonstrating the highest density of CFAE sites. Successful catheter ablation was performed. The patient has remained free of recurrence over 4 months of follow-up. Discussion: This case presents a successful ablation procedure using the emerging strategy of CFAE-targeted ablative lesions. Given the patient's longstanding persistent AF and mechanical mitral valve, the high density of CFAE sites on the left atrial roof was an unexpected finding. Analysis for CFAE sites guided the procedure in a direction that might otherwise not have been undertaken, leading to a successful ablation.