The syndrome of anomalous pulmonary venous drainage with enlarged left atrium reflecting mitral stenosis

Abstract The syndrome of enlarged left atrium in the presence of partial anomalous pulmonary venous return is presented in two forty year old female patients. The cause of the left a trial enlargement was found to be clinically silent mitral valvular stenosis. The hemodynamic features of this syndrome were studied with right heart catheterization and transseptal left atrial catheterization. The anatomy of the left atrium, including the restricted function of the mitral valves, was demonstrated by selective transseptal angiocardiography. In one patient the right main pulmonary arterial branch was occluded by a latex balloon, thus restricting the anomalous pulmonary venous drainage and diverting the total pulmonary blood flow to the left atrium. This caused an instantaneous increase in left atrial pressure and systolic right ventricular pressure These pressures returned to the preocclusion level when the balloon was deflated. The significance of the hemodynamic findings are discussed with respect to the clinical picture.