Unusual systemic venous return with complete absence of the superior caval veins.

The absence of the right superior vena cava (SVC) is usually associated with the presence of a left SVC. This is the first report of a case of systemic venous return without the presence of either upper caval veins. The blood of the upper half of the body was collected into a vessel located on the left side of the spine behind the heart. This vessel crossed over to the right side at the level of the kidneys, draining directly into the inferior vena cava. During correction of tetralogy of Fallot, these findings were confirmed. The terminology and the bearing on interventional planning are discussed.