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From an anatomical standpoint in adults, IVC has 3 segments of different embryologic origin: pre-renal, renal, and post-renal. This type of fusion and partial re-absorption of three pairs of vessels is dependent upon the posterior cardinal veins in the embryo. This complicated evolutionary process can give rise to anatomic malformations that impede vein drainage and favor the development of thrombosis. Duplication of the IVC, the prominent manifestation in this video case report, occurs because the left supracardinal vein fails to regress early in gestation resulting in large veins on both sides of the Aorta that usually joins anterior to the level of the renal arteries to become the suprarenal IVC. When incidentally found, treatment options include observation, placing filters in either systems, or coil-embolization of the duplicated segment plus placing a filter in the right IVC.