Their next area of research was the development of a technique for catheterization of the heart. Using this technique they were able to study and characterise traumatic shock, the physiology of heart failure. They measured the effects of cardiac drugs and described various forms of dysfunction in chronic cardiac diseases and pulmonary diseases and their treatment, and developed techniques for the diagnosis of congenital heart diseases. For this work, Richards, Cournand, and Werner Forssmann were awarded the Nobel Prize for Physiology or Medicine for 1956.