Inferior vena cava filter placement in a left IVC and drainage into duplicated SVC via hemiazygous continuation

Left-sided inferior vena cava (IVC) is the second most common anatomical anomaly of the IVC. We report a drainage pattern of the left IVC into a left duplicated superior vena cava (SVC) diagnosed during IVC filter placement consultation. The patient was a 66-year-old man with symptomatic hematuria caused by bladder cancer diagnosed with IVC thrombus and a left IVC found on a staging computed tomography urogram. The patient underwent computed tomography pulmonary angiogram, which ruled out pulmonary embolism, but demonstrated hemiazygous continuation of the left IVC above the diaphragm to meet a persistent left SVC (prevalence approximately 0.3%-0.5%) (Kim et al. 1995) [1] emptying into the right atrium via the coronary sinus. We report a novel drainage pattern of the left IVC into a duplicated left SVC via hemiazygous continuation.