Tricuspid atresia with absent pulmonary valve and intact ventricular septum: intrauterine course and outcome of an unusual congenital heart defect.

The extremely rare syndrome including absent pulmonary valve associated with membranous tricuspid atresia or severe tricuspid stenosis, intact ventricular septum and patent ductus arteriosus has been reported sporadically in the postnatal literature. This cardiac defect is characterized by right ventricular dysplasia with asymmetrical ventricular septal hypertrophy, ventricular septum bulging into the left ventricle, small right ventricular cavity, membranous tricuspid atresia or severe stenosis with abnormal papillary muscles and leaflets and absence of the pulmonary valve leaflets. The only prenatal case reported so far was diagnosed at 33 weeks of gestation and terminated shortly thereafter; the natural history of prenatally diagnosed cases is therefore unknown. We report on the intrauterine course of a case diagnosed at 17 weeks of gestation that had a favorable postnatal outcome after palliation.