Heart-lung system. Artwork showing a healthy human heart and external and internal lung structures. This view is slightly angled to show the pulmonary blood vessels leading to the lungs. At lower centre is the upper portion of the heart, with the major blood vessels above the heart. These blood vessels include the aortic arch and the vena cava (to left of aorta) that carry blood to and from the body. The lung at upper left is shown in external view. At right, the other lung is transparent, revealing the internal branching blood vessels by which blood from the heart is oxygenated. For this heart with fibrosis, see C006/4269.