On July 3, 1952 Dodrill completed the first successful open heart surgery on the left ventricle of Henry Opitek. He used a machine developed by himself and researchers at General Motors, the Dodrill-GMR, considered to be the first operational mechanical heart used while performing open heart surgery. With E. Hill and R. Gerisch. This paper, which was published in August, 1952, was Dodrill's first report on the operation. In October the team published a second report with a more precisely worded title: "Temporary mechanical substitute for the left ventricle in man," J. Am med. Assoc., 150 (1952) 642-644.