ebstein’s malformation

in this condition, the attachment of the septal leaflet of the tricuspid valve is displaced into the right ventricle. the degree of displacement is variable. obstruction to the right ventricular outflow tract is common, in the form of pulmonary stenosis or atresia. there may be an associated ventricular septal defect but this is uncommon. recent work suggests that the size of the atrial defect in fetal life may dictate the outcome before birth, a restrictive defect being associated with the development of fetal hydrops. secondary lung hypoplasia, as a result of long-standing compression from cardiomegaly, can be a lethal associated feature, especially in those cases identified prenatally. in similar fashion to tricuspid dysplasia, the infant will present with difficulties with ventilation if the cardiomegaly has been severe or with early signs of cyanosis. the early mortality is high if the tricuspid disease is severe and if there is associated obstruction to the pulmonary valve. if the infant survives until the pulmonary artery pressure falls after birth, the degree of tricuspid incompetence will decrease. there is a widely varied prognosis in this condition. symptoms in childhood are associated with a poorer outcome. cyanosis due to a right to left shunt through a patent atrial septum is common. surgical plication procedures or refashioning of the tricuspid orifice to restore the competence of the tricuspid valve, are increasingly successful when this becomes necessary.