Tricuspid valve dysplasia, other than Ebstein's anomaly, is a very rare congenital heart defect. During the prenatal and/or the neonatal periods the clinical picture is very critical. We here report on a newborn infant with severe tricuspid valve dysplasia and 4/4 tricuspid regurgitation, giant right atriomegaly, functional pulmonary atresia with ductal-dependent pulmonary blood flow. The child was successfully submitted to implantation of a 15 mm pulmonary stentless heterograft valve using the top-hat technique.