drains drains anterior region of body anterior vena cava A vein that carries deoxygenated blood from the upper half of the body into the right atrium of the heart. BTO:0002683 EHDAA2:0001962 EHDAA:8726 EMAPA:18417 FMA:4720 GAID:549 MA:0000481 MESH:D014683 NCIT:C12816 Phylogenetic modifications within this basic pattern of arteries and veins are largely correlated with functional changes. In the transition from water to land, gills gave way to lungs, accompanied by the establishment of a pulmonary circulation. In some fishes and certainly in tetrapods, the cardinal veins become less involved in blood return. Instead, the composite, prominent postcava (posterior vena cava) arose to drain the posterior part of the body and the precava (anterior vena cava) developed to drain the anterior part of the body.[well established][VHOG] The mouse has both left and right anterior vena cava. adult humans only have a right. Postnatally the left regresses and becomes non-functional (Wessels and Sedmera 2003). In the mouse, The right pulmonary vein passes dorsal to the right superior vena cava, the left pulmonary dorsal to the left superior vena cava (Biology of the Laboratory Mouse, Green). UBERON:0001585 UMLS:C0042459 VHOG:0001195 cranial vena cava galen:SuperiorVenaCava precava superior caval vein superior vena cava uberon vena cava superior vena maxima vena cava