Duplicate inferior vena cava continuing as a hemiazygos continuation draining into the right atrium via persistent left superior vena cava.

A 59-year-old woman with known breast cancer presented liver lesions. As part of a metastatic workup, a thoracoabdominal enhanced contrast CT was performed. It revealed a persistent left superior vena cava (SVC) which reached the right atrium via an enlarged coronary sinus. This CT-scan also demonstrated the hemiazygos vein which was connected to the left SVC via the left superior intercostal vein. The right SVC was also present (Fig. A). At the abdominal level, CT showed a duplicate inferior vena cava (IVC) which was interrupted at the leveI of the renal hilum and continued as a hemiazygos vein cephalad (not shown). The renal veins drained into the left IVC. There was no corresponding IVC on the right side, except for the hepatic segment which seemed to drain to the right atrium directly by the confluence of the hepatic veins.