Electrophysiological Characteristics and Fluoroscopic Location of the Atrial Tachycardia
(A) Surface 12-lead ECG before surgery. (B) Three-dimensional activation maps of the right atrium during tachycardia showing the earliest atrial activity at the base of giant RAA. (C) Surface ECG after RAA excision. Precordial Leads were removed due to surgical requirement. (D) Three-dimensional activation maps after RAA excision. The earliest signal was recorded in the anterolateral wall of the right atrium. (E) Intracardiac recording during tachycardia with the earliest atrial activation recorded by the ablation catheter preceding the surface P-wave by 87 ms. Ablation performed at this site led to prolongation of the interval between the early sharp potential (red arrows) and far-field atrial activation (black arrows), then dissociation from each other and termination of atrial tachycardia. The last 3 beats were in sinus rhythm. (F) Fluoroscopic images of the successful ablation site by injection of a nonionic contrast via the irrigated ablation catheter. Red arrows indicated the small cardiac vein. ABL = ablation catheter; CS = coronary sinus; LAO = left anterior oblique projection; RAA = right atrial appendage; RAO = right anterior oblique projection; SR = sinus rhythm.