Diagnosis of absent ductus venosus in a population referred for fetal echocardiography: association with a persistent portosystemic shunt requiring postnatal device occlusion.

OBJECTIVE: The purpose of this series was to assess the incidence, anatomic variants, and implications of an absent ductus venosus (ADV) in patients referred for fetal echocardiography. METHODS: We searched our fetal cardiology database for diagnoses of ADV from May 2003 to December 2006. RESULTS: During the study period, we performed 1328 fetal echocardiographic examinations in 990 fetuses. We found 6 cases of ADV (6/1000). Indications for fetal echocardiography were cardiomegaly, dilated umbilical or systemic veins, and extracardiac abnormalities. We identified 5 anatomic variants of ADV. In 2 patients, the umbilical vein connected to the systemic venous circulation by way of the portal sinus: via an abnormal venous channel from the portal sinus to the right atrium (case 1) and presumably via hepatic sinusoids to the hepatic veins (case 2). In the remaining 4 patients, the umbilical vein bypassed the portal sinus and the liver and connected to the systemic venous circulation via an abnormal venous channel: from the umbilical vein to the right atrium (case 3), from the umbilical vein to the inferior vena cava (cases 4 and 5), and from the umbilical vein to the right iliac vein (case 6). All patients survived; 2 required cardiovascular intervention. No intervention was required in 3 patients. CONCLUSIONS: An ADV should be ruled out in a fetus with unexplained cardiomegaly or dilatation of the umbilical vein, systemic veins, or portal sinus. To our knowledge, prenatal diagnosis of an ADV with an abnormal communication between the portal sinus and the right atrium has not been reported previously. The portosystemic communication persisted after birth and required device occlusion.