Effects of Mitral-Valve Replacement on the Pulmonary Vascular Dynamics of Patients with Pulmonary Hypertension

Abstract

THE development of an elevation of the pulmonary vascular resistance is a common complication of severe mitral-valve disease, and this abnormality has been attributed to a combination of obliterative changes in the pulmonary vascular bed and pulmonary vasoconstriction.^{1 2 3} In many patients the elevation of pulmonary vascular resistance is extreme and constitutes the major hemodynamic burden faced by the right ventricle.⁴ Under these circumstances the secondary changes in the pulmonary vascular bed become primarily responsible for many of the clinical findings, including ventricular failure. In view of these considerations determination of the extent to which these abnormalities in the pulmonary circulation . . .