Vascular formation begins in the human embryo on approximately day 18 of development (Gerecht-Nir et al. 2004). Attaining the complex vascularity of the adult involves extensive vascular regression and remodeling via vasculogenesis and angiogenesis to accommodate further growth and development. Specifically, veins of the thoracic wall undergo complex rounds of vascular modeling and remodeling. The formation of a three-membered system of paired veins consisting of the umbilical veins from the chorion, the cardinal veins from the embryo, and the vitelline veins from the yolk sac provides the framework for the eventual development of the thoracic wall veins.