Abnormalities of the heart and great arteries in chromosomally normal fetuses with increased nuchal translucency thickness at 11-13 weeks of gestation.

Pathological examination of trisomic fetuses with increased nuchal translucency thickness at 11-13 weeks of gestation demonstrated a high prevalence of cardiac defects and abnormalities of the great arteries. This study reports the pathological findings observed from the examination of the heart and great arteries of 21 chromosomally normal fetuses with increased nuchal translucency. In 19 of the 21 cases there were abnormalities; the commonest was narrowing of the aorta at the level of the isthmus and immediately above the aortic valve. This finding is different from that in case of trisomy 21, where narrowing of the isthmus is associated with an increased diameter of the aortic valve. These findings suggest that abnormalities of the heart and great arteries may be implicated in the pathogenesis of increased nuchal translucency not only in trisomic fetuses but also in chromosomally normal fetuses. It can be implied that increased nuchal translucency thickness at 10-14 weeks of gestation may prove to be a useful marker for the identification of fetal cardiac abnormalities.