LAUSR

Introduction Catheter ablation is an effective therapeutic strategy for atrial fibrillation (AF). Pulmonary vein (PV) isolation is the cornerstone of catheter ablation for AF. After all PVs were isolated, ablation of non-PV triggers should be attempted. Successful elimination of all the possible AF triggers is considered a better outcome. Mapping of non-PV triggers is usually performed using 3-dimensional anatomic mapping; however, precise mapping of non-PV triggers is sometimes difficult. The electrogram obtained using the reference catheter is not suitable to use as the reference, because of poor stability of the catheter, ventricular electrogram overlap, or dull potential after cardioversion. A new technique, self-reference mapping, does not require other reference catheters, because it uses the previous earliest activation site recorded with the PentaRay NAV (PEN) catheter (Biosense Webster Inc., Diamond Bar, CA) as the reference (Figure 1).