Forssmann's cardiac catheterization

Since 1861, when Chauveau and Marey led manometers from the neck vessels into the heart chambers of a living animal, physiologists had measured pressures inside animal hearts. In patients the right side of the heart was out of reach. Doctors could sample arterial blood and measure pressure in peripheral arteries and surface veins, but not the pressure in the right ventricle or the mixed venous blood returning to the heart. As late as 1928 a textbook held that in man one was confined to indirect methods.

Werner Forssmann passed his state medical examination in Berlin in 1929 and went for surgical training to the August Victoria Home at Eberswalde. Working from Chauveau and Marey's animal method, he put a cannula into a vein at his own elbow, pushed a catheter 65 cm along it, and walked to the X-ray department, where a film showed the tip lying in his right atrium. He described the method in the Klinische Wochenschrift in November 1929.

A few clinics, in Prague and Lisbon, took the method up, and in 1930 O. Klein in Prague used the catheter to measure cardiac output by Fick's principle in a series of patients. Forssmann himself met criticism that G. Liljestrand of the Nobel committee later called exaggerated and based on an unfounded belief that the procedure was dangerous, and he lost the will to continue. He trained in urology, was a prisoner of war until 1945, and later practised as a urologist at Bad Kreuznach.

In New York, André Cournand and Dickinson Richards, working in the Columbia University division at Bellevue Hospital, wanted direct measurements from the right heart for their studies of circulation in disease. After several years of preparation their group reported cardiac catheterization in man in 1941. They used it to show that wound shock during the Second World War involved a large fall in cardiac output from reduced return of blood to the heart, to measure shunts in congenital heart disease, and to record raised pulmonary artery pressure in chronic lung disease.

Forssmann, Cournand and Richards shared the 1956 Nobel Prize in Physiology or Medicine. In his Nobel lecture Forssmann noted that Cournand, too, had faced ethical objections to the catheter in 1941, twelve years after his own. He died on 1 June 1979.