Mitral commissurotomy with pump standby

Mitral commissurotomy has been performed on twenty-six patients, eight of whom have required mitral valve replacement as a result of incomplete opening or dilator injury. There was one death. It is believed that the essential pathologic condition in dilator injuries or incomplete commissurotomy is due to the subvalvular fusion of the chordae tendineae. With open commissurotomy the fusion can be relieved under direct vision without injury to the mitral leaflets. The greatest hazard from open commissurotomy is air embolus. This can be obviated by using the technic outlined. The long-term results from open commissurotomy remain to be determined.