We appreciate the thoughtful comments of Dr. Chase, Dr. Devi A and Dr. John regarding our case report [1] of a patient who underwent AV junction ablation via a congenitally abnormal venous system. Our patient had an interrupted inferior vena cava which continued as the azygos vein, in turn draining into the superior vena cava. Ablation was successfully performed with the ablation catheter throu...

Superior vena cava (SVC) occlusion can be clinically recognized in the acute setting when the stenosing process does not allow the development of collateral venous channels, which guarantee the venous drainage to the right heart. On the contrary, when the obstruction develops progressively, the diagnosis of SVC obstruction may remain undiagnosed. In the present case, the presence of SVC thrombo...