Clarence Walton Lillehei (October 23, 1918 – July 5, 1999), was an American surgeon who pioneered open-heart surgery, as well as numerous techniques, equipment and prostheses for cardiothoracic surgery. Background Clarence (often called "Walt") Lillehei was born in Minneapolis, Minnesota, the son of Dr. Clarence Ingvald Lillehei (1892-1973) and Elizabeth Lillian (Walton) Lillehei (1891-1973). He attended West High School in Minneapolis in 1935. He attended the University of Minnesota at the age of 17. He earned 4 degrees at the University of Minnesota, including his B.S. (with distinction) in 1939, his M.D. (Alpha Omega Alpha) in 1942, his M.S. in physiology in 1951, and his Ph.D. in surgery in 1951. Career In 1944, Alfred Blalock at Johns Hopkins University Hospital had begun successfully performing surgery on the great vessels around the heart to relieve the symptoms of tetralogy of Fallot, demonstrating that heart surgery could be possible. Lillehei participated in the first successful surgical repair of the heart on 2 September 1952. That historic operation, using hypothermia, was led by his longtime friend and colleague, F. John Lewis. Lillehei was a professor in the Department of Surgery at the University of Minnesota from 1951 to 1967. However, hypothermia, gave only a relatively brief time, up to 10 minutes, during which surgery could be performed and was therefore not suited for complex congenital defects within the heart. To resolve this problem, Lillehei performed operations using cross-circulation, in which a donor was hooked up nearby to take up the pumping and oxygenation functions of the patient who was being operated on. Using this technique, Lillehei led the team that performed successful repair of a ventricular septal defect on March 26, 1954. Although the repair was successful, the patient, 13-month-old Gregory Glidden, died 11 days later of suspected pneumonia. Lillehei and his team continued to use cross-circulation for a total of 44 open-heart operations in the following year, of which 32 patients survived. These operations included the first repairs of the atrioventricular canal and tetralogy of Fallot. In July of that year, a successful operation was performed on patient Michael Eugene Shaw of Litchfield, Minnesota. Lillehei cooperated with Professor Moshe Gueron and Professor Morris J. Levy, who were both considered among "The Cardiology Founders of Israel" by doing the first cardiac puncture catheterization, which was used on 80 patients in 1964. In 1958, Lillehei was responsible for the world's first use of a