A cyanotic newborn is described to illustrate and discuss the rare transient tricuspid insufficiency together with functional pulmonary atresia. Etiologically the manifold causes of perinatal asphyxia are to be taken into consideration. The clinical appearance corresponds to type A of transient myocardial dysfunction according to the classification of Rowe together with respiratory distress syndrome and heart failure. Pathogenetically the disease is based on the different histological consequences of myocardial ischaemia of the right ventricle in connection with a delayed fall of the pulmonary arterial resistance. Fetal connections lead to a pronounced right-to-left-shunt. The diagnosis is primarily established by the way of clinical and echocardiographic investigation and pulsed doppler examination. The most important differential diagnosis are in Ebstein-anomaly, obstruction and atresia of the right ventricular outflow tract. Therapy is conservative. Its aim is to improve myocardial performance and to lower right ventricular afterload. Outcome of patients with neonatal tricuspid insufficiency is uncertain and depends on the severity of myocardial ischaemia. In our patient the course has been uneventful after initial difficulties.