Figure 2: Intracardiac echocardiogram during the electrophysiology study and ablation. Panel A Intracardiac echocardiogram of the atrial tachycardia (AT) with atrioventricular (AV) 2 to 1 conduction and preexcitation. Panel B 12 leads ECG of the AT. Panel C ventricular pacing with eccentric atrial activation.Panel D intracardiac signal at the successful ablation site for the AP.