Ventilatory Cost of Exercise Before and After Mitral Valvotomy

We have previously reported measurements of the maximum ventilatory capacity and the ventilatory requirements for a standard exercise in 26 patients with mitral stenosis (Stock and Kennedy, 1953). A small but variable reduction in maximum ventilatory capacity was noted which appeared to bear little relation to the severity of the patients' symptoms. On the other hand, it was found that increasing disability in mitral stenosis tended to be associated with an increasing ventilatory cost of exercise. We suggested that this increased ventilation might prove useful as an objective index of disability.