Aberrant course of Swan-Ganz catheter revealing persistent left superior vena cava.

The presence of a persistent left superior vena cava (PLSVC) is the most common congenital disorder of thoracic venous anomaly. Failure of the left anterior cardinal vein to degenerate results in persistent left superior vena cava. It is usually discovered during central venous catheterization or surgical repair of congenital heart disorder. Although most patients with isolated PLSVC or double SVC are asymptomatic, there are some important clinical implications in certain situations, such as central venous catheterization or cardioplegia, which may result in serious complications. In this article, we present a case with PLSVC revealed by chest roentgenogram after pulmonary artery catheterization via left internal jugular vein. We also discuss the role of computed tomography in the diagnosis of PLSVC.