SINCE March 31, 1950, at this hospital 19 patients have been accepted for surgical treatment of the mitral valve. The word "commissurotomy" in the title indicates that of the several operative procedures described or recommended during the past few years, that of Bailey and his associates1 has appeared to be the most practical. This method involves an auricular approach to the stenosed valve with inspection by "digital vision" and an attempt to widen the orifice by cutting at the angles or commissures without the sacrifice of any valve leaflet structure, thus avoiding the production or augmentation of regurgitation. A similar plan was also evolved by Harken2 and by Brock,3 although the latter has been inclined to do most of the splitting with the finger alone.
Two types of operation have been avoided. The first is the method of insertion of a valvulotome through the ventricular wall with