First‐trimester Cardiac Assessment in Fetuses With Increased Nuchal Translucency: A Diagnostic Accuracy Study
JingJing Yu, YueHua GuABSTRACT
Objective
To evaluate the independent and incremental value of a standardized first‐trimester binary cardiac assessment for screening severe congenital heart disease (CHD) in fetuses with increased nuchal translucency (NT).
Method
This single‐center retrospective diagnostic accuracy study included 223 singleton fetuses with NT ≥ 3.0 mm at 11–13 + 6 weeks of gestation who underwent prenatal screening at our hospital between January 2019 and December 2023. First‐trimester binary cardiac assessment was performed through blinded review of archived ultrasound images. Clinical and screening variables, including NT thickness and pregnancy‐associated plasma protein A (PAPP‐A), were collected. Missing serum marker data were addressed using multiple imputation. Logistic regression and receiver operating characteristic (ROC) curve analyses were used to assess the predictive and diagnostic performance of the cardiac assessment alone and in combination with conventional screening indicators. The DeLong test was used to compare the baseline model (NT + PAPP‐A) with the incremental model (NT + PAPP‐A + cardiac assessment).
Results
A positive first‐trimester cardiac assessment was independently associated with severe CHD (adjusted OR = 4.02, 95% CI: 1.09–14.87). In the primary imputed analysis, the baseline model (NT + PAPP‐A) had an AUC of 0.840 (95% CI: 0.772–0.912), and the incremental model adding cardiac assessment had an AUC of 0.879 (95% CI: 0.812–0.945); however, the DeLong test did not show a statistically significant difference ( p = 0.243). The cardiac assessment showed particularly high sensitivity for left‐sided obstructive cardiac malformations (90.0%).
Conclusion
A standardized first‐trimester cardiac assessment is independently associated with severe CHD in fetuses with thickened NT. Adding it to NT thickness and maternal PAPP‐A did not significantly improve model discrimination in this retrospective cohort, although the AUC increased numerically. Prospective multicenter studies are needed to determine whether this combined strategy provides incremental value.