Heart-lung interactions in health and disease

Heart-lung interactions is a term applied to the complex interplay between the functions of the heart and respiratory systems. This interdependence of respiratory and cardiac function takes place at several levels. First is a functional linkage between the respiratory and cardiovascular systems in the transport of oxygen and carbon dioxide. Second are reflex and humoral interconnections between the two systems. Third are mechanical interactions between the heart and lungs, which are elastic structures sealed within an expandable thorax. In recent years, most attention has been focused on these mechanical interactions, but it is appropriate to consider also the other ways the heart and lungs interact.