We report an interesting case of a man with a persistent left superior vena cava (PLSVC) with left azygos vein who underwent electrophysiological evaluation. Further evaluation revealed congenital dilated azygos vein, while a segment connecting the inferior vena cava (IVC) to the hepatic vein and right atrium was missing. The azygos vein drained into the superior vena cava, and the hepatic veins drained directly into the right atrium. The patient did not have congenital anomalies of the remaining thoracoabdominal vasculature.