Prenatal diagnosis of hepatic interruption of the inferior vena cava with azygos/hemiazygos continuation without structural heart defects: A case series

Objectives To describe fetal spectrum and echocardiographic characteristics of interrupted inferior vena cava (IIVC) with azygos/hemiazygous continuation without other structural heart defects and to evaluate its association with visceral heterotaxy and isomerism, extracardiac and genetic anomalies, and to review neonatal outcome. Methods This was a retrospective study of 14 fetuses with a confirmed diagnosis of IIVC with normal intracardiac anatomy. The following variables were collected; indication for referral, gestational age at diagnosis; associated isomerism and visceral heterotaxy, heart rhythm, genetic and extracardiac abnormalities, and fetal/neonatal outcome. Results Among 36 fetuses with IIVC, 14 cases (38.8%) had normal intracardiac anatomy. These IIVC cases correspond to 0.19% (14/7250) of all fetal cardiac examinations, and to 1.5% (14/922) of all cardiac abnormalities. Six patients had visceral abnormalities. Atrial appendage morphology was clearly depicted in three fetuses, both appendages were left. One fetus had bradyarrhythmia revealing atrial ectopic rhythm. Six fetuses did not have any concomitant cardiac or visceral abnormalities, therefore regarded as isolated. All babies were delivered at term with a good prognosis. Conclusion Our study has shown that almost half of the IIVC cases without intracardiac structural anomalies displayed other findings of isomerism while the other half was isolated benign vascular variant. Therefore, prenatal diagnosis of IIVC should prompt a comprehensive evaluation for cardiac, situs, and visceral anomalies. The outcome is favorable. Isolated IIVC is an extremely rare vascular anomaly. The prevalence of IIVC with structurally normal heart was 0.16% in general population, it was 1.3% in fetuses with cardiac anomalies in our series. Heterotaxy may be found even in the absence of intracardiac anomaly in IIVC. IIVC not accompanied by cardiac anomalies are mostly asymptomatic, even cases with heterotaxy have a good prognosis. Prognosis of IIVC depends on accompanying anomalies, such as cardiac anomalies, heart block, biliary atresia, and intestinal malrotation.