To determine whether first trimester nuchal translucency (NT) measurement is a useful screening tool for major congenital heart disease (CHD) in the absence of aneuploidy.
Unselected patients with singleton pregnancies at 10 3/7 to 13 6/7 weeks were recruited at 15 US centers to undergo NT screening. Pregnancy and pediatric outcomes were recorded and medical records review performed on all cases of suspected CHD. Cases with aneuploidy were excluded from the analysis. Major CHD included defects known to have poor perinatal outcomes or ductal dependency after birth. The sensitivity, specificity, and positive and negative predictive values of NT measurements in the detection of major CHD were determined using different cut-offs (≥2.0 MoM, ≥2.5 MoM, ≥3.0 MoM). Odds ratios (95% CI) were calculated for the different cut-offs and P value < .05 was considered significant.
33,968 patient records with cardiac outcome data were available for this analysis. Overall, there were 195 cases of CHD (incidence 5.7/1000), of which 43 (22.1%) were major (incidence 1.3/1000). Of the 43 major defects, 35 (81.4%) occurred in patients with NT < 2.0 MoM. The incidence of major CHD increased with increasing NT MoMs as listed in Table I. Table II lists the screening properties, OR, and 95% CI of different NT MoMs cut-offs for major CHD.
NT assessment in the first trimester lacks the characteristics of a good screening tool for major CHD in a large, unselected population. However, NT ≥ 2.0MoM is a marker for major CHD and warrants referral for fetal echocardiography.
Table IIncidence of Major CHD
Table IIDifferent NT Cut-Offs and Detection of Major CHD
© 2004 Elsevier Inc. Published by Elsevier Inc. All rights reserved.