Prenatal diagnosis of intrahepatic communications of the umbilical vein with atypical arteries (A-V fistulae) in two cases of trisomy 21 using color Doppler ultrasound

We report on two cases of the prenatal diagnosis of arteriovenous communica tion between the intra-abdominal umbilical vein and atypical arteries. The diagnosis was made by color and spectral Doppler and 'color power angiograp hy'. Both cases presented with hydrops fetalis, one at 14 and the other at 31 weeks of gestation. In the first case, color Doppler demonstrated an aty pical arterial vessel connecting the umbilical vein with the aorta; the duc tus venosus was patent. Echocardiography showed a so-called atrioventricula r canal. In the second case, a complex intrahepatic vascular malformation w as found. Color Doppler demonstrated communications between the umbilical v ein and the hepatic artery and an atypical artery; the ductus venosus was p arent. In the latter case polyhydramnios, duodenal atresia and macroglossia were additionally detected. In both cases, fetal karyotyping revealed tris omy 21. The first case resulted in a missed abortion, the second in a still birth. All findings were confirmed on autopsy Of interest is that both fetuses were affected with trisomy 21. The increas ing use of color Doppler in prenatal diagnosis, especially in hemodynamical ly compromised fetuses, will help to determine the actual incidence of comp lex vascular malformations of the umbilical vein and to elucidate the impac t of such malformations on fetal outcome.