The dawn of open-heart surgery occurred at the University of Minnesota on September 2, 1952, when Dr John Lewis and his surgical team closed an atrial septal defect using total-body hypothermia and inflow stasis. Eighteen months later on March 26, 1954, Dr C. Walton Lillehei and his surgical team used a parent as a biologic oxygenator to repair a ventricular septal defect in a 1-year-old boy. This technique of cross circulation was then used in a total of 45 children during the next 16 months to successfully repair tetralogy of Fallot, atrioventricular canal, and ventricular septal defect. Remarkably, two thirds of these children were discharged from the hospital. Thirty years later, Dr Lillehei reported that 17 of his 27 patients with repair of a ventricular septal defect had survived and were all New York Heart Association class I. These landmark operations in the open heart could not have been achieved by Drs Lewis and Lillehei without the remarkable support that they received from their surgical chief, Dr Owen Wangensteen. Doctor Wangensteen would later state in his book, The Rise of Surgery, that: "The outstanding contribution to the advancement of surgery in the 20th century has been the development of open-heart surgery."