Non-contact mapping of the human left atrium to guide ablation of focal atrial fibrillation

Focal left atrial (LA) tachycardias/ectopy (LATs) that may initiate atrial fibrillation (AF) are often difficult to initiate, non-sustained, and may have multiple origins, often in one or more pulmonary veins (PV). Thus, mapping with conventional techniques is often difficult. The authors tested the hypothesis that a non-contact mapping system capable of global simultaneous mapping of >3000 points in the LA, would facilitate ablation of LAT. The non-contact mapping system was able to rapidly identify the origin of human LATs and focal AF despite the infrequency and short duration of initiating ectopy and guide a conventional mapping catheter to successful ablation sites. The authors also observed that, although isoproterenol is the most successful method of initiating LATs, these originate from multiple sites and therefore appear to be of limited clinical significance.