Patency of the left superior vena cava (persistent left superior vena cava--PLSVC), although uncommon, is the most frequent anomaly of the thoracic vessels. It has been diagnosed in 0.3-0.5% of the general population. PLSVC results from the abnormal persistence of an embryological vessel that normally involutes into the coronary sinus during fetal life. Catheterization of this vessel, including hemodialysis (HD) catheter placement, appears to be safe if adequate drainage of the PLSVC to the right atrium exists. We present the case of a 50-year-old HD patient in which the placement of a catheter through the left internal jugular vein, needed for HD treatment, revealed a PLSVC. After the demonstration of adequate draining of the vessel into the right atrium, replacement of this catheter for a cuffed tunneled HD catheter was done, which has since been used successfully for HD.