Mediastinal Veins and Anomalies

The chapter titled abnormalities of systemic veins discusses a series of mediastinal venous anomalies and tributaries that may produce confusing imaging findings. Such findings may be seen on a radiograph that shows an abnormal course of a central line or catheter in one of these anomalous vessels. The more frequently encountered systemic vein variants are presented, namely left superior vena cava (SVC) and azygous continuation of an interrupted inferior vena cava (IVC). In these conditions the normal connection of a right-sided vena cava to right atrium may be altered. Commonly encountered venous tributaries, including the left superior intercostal vein (which produces the aortic nipple on radiography), the left pericardiophrenic vein, and systemic to pulmonary vein collaterals will also be included. The latter may result in right-to-left shunting and cyanosis.