Prenatal and postnatal imaging in isolated interruption of the inferior vena cava with azygos continuation

Prenatal diagnosis of left atrial isomerism

“…In our series all fetuses had an interrupted inferior vena cava with azygous continuation. However, an interrupted inferior vena cava has been reported without associated left atrial isomerism 25. It is evident from table 1 that, although a common atrioventricular junction is the most typical malformation, associated intracardiac malformations tend to be varied and complex.…”

Azygos Vein Z Scores in Healthy Fetuses and Fetuses With Venous Malformations Related to the Azygos Vein

“…The “double‐vessel” sign observed on the sonographic abdominal circumference plane and 4‐chamber view has classically been a marker of an interrupted inferior vena cava, 21 – 23 but recognition of this typical sign mainly depends on the experience of the sonographers. In this study, a more objective and quantitative method was used to identify the double‐vessel sign.…”

Should we include bicaval view in the study of the fetal heart?

“…The embriogenesis of IVC is a complex process involving the formation of several anastomoses between three paired embryonic veins. Interruption of IVC with azygos continuation represents the most common abnormality involving these veins 4 . The IVC is composed of four portions: hepatic, prerenal, renal and postrenal.…”

“…These portions originate from the formation, fusion and regression of the cardinal veins. The azygos system is derived from the supra cardinal veins 3,4 . Failure to fuse of the prerenal segment with the caudal portion of the hepatic segment results in interrupted IIVC and venous flow beyond the interruption proceed through the azygos system draining into the right atrium via the superior vena cava 4 .…”