Human heart. Computer artwork of a healthy human heart. The main blood vessels of the heart are visible at the top of the image. At upper left is the vena cava, where blood arrives from the body. Blood is pumped through that side of the heart to the lungs and back to the heart through the pulmonary system of blood vessels (upper right). Oxygenated blood is then pumped to the rest of the body through the main artery, the aorta (arched, upper centre), which has three smaller arteries branching from it at top centre. The heart muscle itself is supplied with fresh blood through the coronary arteries (purple, branched), seen on the surface of the heart.