André F. Cournand shared the 1956 Nobel Prize in physiology or medicine with German surgeon Werner Forssmann and American physiologist Dickinson Woodruff Richards, Jr. for pioneering work in the field of cardiac and pulmonary physiology. Cournand helped develop the technique of cardiac catheterization, which permits blood samples to be obtained from the heart for determining cardiac abnormalities.

Cournand was born in Paris on September 24, 1895. His father, Jules Cournand, and his grandfather were both dentists. At age 15, young André began to accompany his parents to the salon of a physician friend where many internationally known scientists met and discussed issues of their day.

In 1913, Cournand received his bachelor's degree from the University of Paris-Sorbonne, where he also began his medical studies in 1914. But in that year the first World War broke out, and many medical professors enlisted in the army. In the spring of 1915, Cournand decided to postpone...