THE RIGHT VENTRICLE AND SMALL PULMONARY ARTERIES IN ANEURYSMAL DILATATION OF THE LEFT ATRIUM

Abstract

In 9 cases of aneurysmal dilatation of the left atrium the state of the mitral valve, the thickness of both ventricles, and the medial thickness of the muscular pulmonary arteries were recorded. In 7 there was tight pure mitral stenosis, in 1 there was combined stenosis and incompetence, and in 1 there was miral incompetence. Only 3 showed right ventricular hypertrophy and hypertensive pulmonary vascular disease and in 2 of these the capacity of the left atrium had been secondarily reduced by laminated thrombus. These findings suggest that in some instances of tight mitral stenosis, extreme dilatation of the left atrium is in some way the cause, or the result of failure of development of hypertensive pulmonary vascular disease.