Early fetal endocardial fibroelastosis and critical aortic stenosis: a case report. 
Endocardial fibroelastosis is characterized by an abnormal thickening of the endocardium of one or both ventricles; the disorder may occur with or without other cardiac anomalies.  A diagnosis of endocardial fibroelastosis in utero using fetal echocardiography may be made on the basis of increased echodensity of the endocardium and poor contractility of the ventricle.  We describe a case of very early diagnosis of fibroelastosis and aortic valve stenosis observed in utero at 14 weeks' gestation by transvaginal echocardiography.