Ablation of Atrial Tachycardia From a Giant Left Superior Vena Cava Using Integration With Computed Tomographic Imaging

Abstract

A 49-year-old woman affected by the Turner syndrome with a history of repaired congenital cardiomyopathy and persistent atrial tachycardia was referred to our center for radiofrequency ablation. At 11 years of age, she had undergone a surgical closure of an ostium secundum atrial septal defect (direct suture) combined with ligation of a persistent left superior vena cava, the embryological precursor of the ligament of Marshall, at the level of its connection to the coronary sinus. At hospitalization, her electrocardiogram showed an atrial tachycardia (cycle length 375 ms) with long phases of 1:1 atrioventricular conduction. Before the procedure, a computed tomography (CT) scan was performed to merge the anatomic data with the electrophysiological findings during the procedure (CARTO-MERGE, Biosense Webster, Inc, Diamond Bar, Calif). The preacquired CT image, processed with CARTO-MERGE system, showed the presence of a giant left superior vena cava (isolated from the coronary sinus) and a sinus venosus defect (SVD) associated with a right-sided anomalous pulmonary venous connection. In detail, both right superior pulmonary vein and right inferior pulmonary vein drained into the superior …