Homozygous familial hypercholesterolaemia is characterized by cutaneous xanthoma development from infancy, precocious and accelerated atherosclerosis with clinical signs of ischemic heart disease and frequent involvement of left heart valves resulting in stenosis and/or incompetence. Two cases are described of this condition, both associated with aortic stenosis. In one case mitral incompetence and thromboembolic pulmonary hypertension were also found. The mitral valve is involved in the atherosclerotic process at the level of the cusps. These become thickened and stiff. Aortic stenosis is mainly due to atheromas infiltrating the Valsalva sinuses and the ascending aorta. Pulmonary hypertension, never reported before in this disease, is probably due to concomitant atheromatosis involving the pulmonary artery with secondary fatty embolism.