Response to: Percutaneous closure of a secundum atrial septal defect through femoral approach in an adult patient with interrupted inferior vena cava and azygos continuation

We appreciated the paper of Alizade et al. (1) entitled ‘’Percutaneous closure of a secundum atrial septal defect through femoral approach in an adult patient with interrupted inferior vena cava (IVC) and azygos continuation’’. The authors clearly highlighted that interventional endovascular maneuvers normally coded for vascular access, materials, and technique, must be carefully re-evaluated in the preoperative planning, in case of congenital anomalies involving the systemic venous return to the right atrium. Congenital anomalies of the deep thoracoabdominal venous system are caused by variations in the development during embryogenesis. Azygos continuation of the IVC, like the case described by the authors, is a very rare venous variant. It is characterized by the absence of the IVC segment between the renal and hepatic veins