Cardiac defects, nuchal edema and abnormal lymphatic development are not associated with morphological changes in the ductus venosus.

Background: In human fetuses with cardiac defects and increased nuchal translucency, abnormal ductus venosus flow velocity waveforms are observed. It is unknown whether abnormal ductus venosus flow velocity waveforms in fetuses with increased nuchal translucency are a reflection of altered cardiac function or are caused by local morphological alterations in the ductus venosus.

Aim: The aim of this study was to investigate if the observed increased nuchal translucency, cardiac defects and abnormal lymphatic development in the examined mouse models are associated with local changes in ductus venosus morphology.

Absence of an anatomical origin for altered ductus venosus flow velocity waveforms in first-trimester human fetuses with increased nuchal translucency.

Objective: To perform a morphological evaluation of the ductus venosus, heart and jugular lymphatic sac (JLS) in first-trimester human fetuses with normal and abnormal ductus venosus flow velocity waveforms (DV-FVWs) and normal and increased nuchal translucency (NT).

Method: Postmortem examination was performed on fetuses with increased NT or structural malformations with previous NT and DV-FVW measurements. Ductus venosus morphology was examined using markers for endothelium, smooth muscle actin (SMA), nerves and elastic fibers.

Increased nuchal translucency origins from abnormal lymphatic development and is independent of the presence of a cardiac defect.

Objective: To assess whether cardiac failure, because of cardiac defects, and abnormal jugular lymphatic development are involved in nuchal edema (NE) - the morphological equivalent of increased nuchal translucency - in various euploid mutant mouse models.

Method: Mouse embryos with lymphatic abnormalities and NE (Ccbe1(-/-)), with cardiac defects and NE (Fkbp12(-/-), Tbx1(-/-), Chd7(fl/fl);Mesp1Cre, Jarid2(-/-NE+)) and with cardiac malformations without NE (Tbx2(-/-), Pitx2(-/-), Fgf10(-/-), Jarid2(-/-NE-)) were examined. Embryos were analyzed from embryonic day 11.

Involvement of neurons and retinoic acid in lymphatic development: new insights in increased nuchal translucency.

Objective: Increased nuchal translucency originates from disturbed lymphatic development. Abnormal neural crest cell (NCC) migration may be involved in lymphatic development. Because both neuronal and lymphatic development share retinoic acid (RA) as a common factor, this study investigated the involvement of NCCs and RA in specific steps in lymphatic endothelial cell (LEC) differentiation and nuchal edema, which is the morphological equivalent of increased nuchal translucency.