One hundred seventeen surgically treated cases of valvular rheumatic heart disease; with preliminary report of two cases of mitral regurgitation treated under direct vision with aid of a pump-oxygenator.

• Among 117 patients treated surgically for valvular rheumatic heart disease, 92 were found to have mitral stenosis as the predominant abnormality. Regurgitation was associated with the stenosis in 41 of these patients, but the degree of regurgitation was decreased more frequently than it was increased after the operation of commissurotomy. In 51 patients the stenosis was not accompanied by regurgitation, and only 5 of these patients exhibited some regurgitation after commissurotomy. When stenosis was severe, improvement usually followed commissurotomy regardless of the type of valve encountered and in spite of an imperfect commissurotomy. Difficulties encountered at operation included thrombi, old or recent, which were found in the left auricular appendix in 26 patients. The total operative mortality, including deaths up to one year, was 12 (13%). The urinary output must be watched and steps taken to control the intake of water and electrolytes. Twenty patients were found to have aortic stenosis as the predominant abnormality, and five of these had associated mitral stenosis which was treated at the same operation; a new instrument was developed for use as aortic dilator, and in this series there were no operative deaths. The development of a new oxygenating pump system made it possible to perform two operations for acquired mitral insufficiency by open cardiotomy and direct vision. The recovery of one of these patients who had a total cardiopulmonary bypass for 17 minutes, and the success in correcting stenosis and regurgitation simultaneously in other cases, justify the hope for further development of the surgical treatment of valvular rheumatic heart disease.