Cardiac surgery changed significantly after World War II. In 1948 four surgeons carried out successful operations for mitral stenosis resulting from rheumatic fever. Horace Smithy (1914–1948) of Charlotte, revived an operation due to Dr Dwight Harken of the Peter Bent Brigham Hospital using a punch to remove a portion of the mitral valve. Charles Bailey (1910–1993) at the Hahnemann Hospital, Philadelphia, Dwight Harken in Boston and Russell Brock at Guy's Hospital all adopted Souttar's method. All these men started work independently of each other, within a few months. This time Souttar's technique was widely adopted although there were modifications.