The interaction of the heart and lungs is probably the most important aspect of life and
survival. Fortunately, it is not difficult to understand the fundamentals. The purpose of the
lungs and their ventilation is to present oxygen to the circulation via the alveoli and to
receive carbon dioxide from the circulation and then expel it. The relations of the heart and
lungs and the matching of blood flow to the various organs with ventilation and lung
perfusion may be disrupted by a variety of congenital or acquired heart malformations. They …