Early Reduction of Pulmonary Vascular Resistance after Mitral-Valve Replacement

Abstract

PULMONARY-artery pressure rises out of proportion to the left atrial, pulmonary venous and pulmonary capillary pressure in some patients with elevated left atrial pressure secondary to mitral stenosis.¹ This rise results in severe pulmonary hypertension and pulmonary vascular disease as manifested by marked elevation of calculated pulmonary vascular resistance. Wood² found that 12 per cent of 500 patients with mitral stenosis had severe pulmonary vascular disease defined as pulmonary vascular resistance greater than 10 units (greater than 800 dyne sec. cm.^-5). The mechanism of the inordinate increase in pulmonary-artery pressure is not clear.The presence of pulmonary vascular disease . . .