Figure 3a. RFCA technique. (a) Fluoroscopic image depicts the ablation electrode (arrowheads) and the intracardiac echocardiography catheter (arrow) within the left superior pulmonary vein ostium. (b) As thermal energy is applied, an electroanatomic virtual map (CARTO-Biosense/Webster, Diamond Bar, Calif) shows the aggregate of ablated regions. Each red sphere represents a few millimeters of ablated tissue.