Levoatrial Cardinal Vein in a Series of Five Prenatal Cases with Hypoplastic Left Heart Syndrome and Intact Atrial Septum.

Purpose The rare finding of a levoatrial cardinal vein (LACV) represents a pulmonary-systemic connection providing an alternative egress from the left atrium for pulmonary venous blood in fetal cardiac malformations with severe left heart obstruction and intact atrial septum (IAS). The purpose of the study was the description of the various sonographic and Doppler findings, the peripartal management and neonatal outcome of this rare cardiovascular anomaly. Materials and Methods Retrospective review of 53 967 echocardiograms in our fetal database between 2002 and 2013 for cases with an LACV. The various sonographic findings of the LACV, the associated cardiac findings and the perinatal management were assessed. Results The presence of a decompressing LACV was documented in 5/27 (18.5 %) of all fetuses with hypoplastic left heart syndrome and intact atrial septum. All five fetuses were diagnosed with an LACV originating from the left atrium and draining either into the innominate vein (two cases), the azygos vein (one case), or directly into the vena cava superior (two cases). Elevated pressure in the pulmonary veins was present in the three cases with obstruction of the LACV. Two pregnancies were terminated, two neonates received compassionate care and one neonate died despite atrioseptectomy. Conclusion LACV in the presence of HLHS and IAS is a rare condition with various forms of pathway and degree of obstruction and generally has an unfavorable prognosis. The presence of obstruction can be diagnosed by spectral Doppler of the LACV. Therefore, in cases of HLHS and IAS, careful sonographic evaluation for aberrant vessels is mandatory. © Georg Thieme Verlag KG Stuttgart · New York.