Abstract

We have examined biopsies of the lingula of the upper lobe of the left lung from 85 patients undergoing mitral valvotomy and have correlated the presence of vascular changes and fibrosis of the lung tissue with pulmonary vascular resistance, the degree and type of mitral stenosis, and the duration of pulmonary symptoms. Factors which significantly affected the prognosis were high pulmonary artery pressures, high vascular resistance, and narrowing of the pulmonary arteries; but, above all, pulmonary fibrosis. The prognosis for patients with mitral incompetence was less favourable than for those without incompetence, especially if there was increased pulmonary vascular resistance and pulmonary hypertension with axis deviation in the electrocardiogram.