Atrial Fibrillation: Anatomical Guidance Is Superior to Electrophysiological Guidance for Ablation

Abstract

Electrophysiologically guided ablation was the initial strategy applied in patients with focal atrial fibrillation (AF), but electroanatomical mapping systems have had an increasingly important role in successful elimination of both paroxysmal and chronic AF [1–3]. Currently, targets for ablation of AF are increasingly being selected on the basis of anatomical considerations [4–14]. Therefore, ablation strategies that are based more on anatomical considerations than on mapping are needed to improve the efficacy of catheter ablation of AF. It has become accepted that detailed anatomical knowledge of the number, size, and shape of the pulmonary veins (PVs), especially the atriopulmonary junction and the tributaries and branching pattern of the PVs, is of critical importance in PV ablation for AF. Recent experimental studies have demonstrated a correlation between anatomy and electrical activation; in particular, segmental muscle disconnection, a differential muscle narrowing at PV-LA junctions, and complex fiber orientations within the PV provide robust anatomical bases for conduction disturbances at the PV-LA junction and complex intra-PV conduction patterns. Consequently, new technologies, including the CARTO system using detailed anatomical images, have become available for catheter guidance and mapping, and their practicability has been validated by our group [2, 3]. Therefore, the importance of anatomically based catheter ablation procedures is now well recognized. Catheter ablation of isthmusdependent atrial flutter, which is based strictly on anatomical criteria, is regarded as the first-line therapy in atrial flutter. Similarly, the results of catheter ablation for AF have become better and better as procedures have been based increasingly on anatomical considerations. Therefore, future mapping technology that provides more specific anatomical information on critical areas will ultimately result in catheter ablation becoming first-line therapy for both paroxysmal and chronic AF.