Subjective and Objective Sonographic Assessment for the Prenatal Detection of Neonatal Coarctation of the Aorta

The objective of this study was to assess the performance of antenatal ultrasound markers in detecting neonatal coarctation of the aorta (CoA).

We performed a retrospective study including fetuses with suspected CoA and no other cardiac abnormalities. Data obtained from antenatal ultrasounds included subjective assessment of ventricular and arterial asymmetry, appearance of aortic arch, presence of a persistent left superior vena cava, and objective Z-score measurements of the mitral, tricuspid, aortic (AV), and pulmonary (PV) valves. Performance of antenatal ultrasound markers in predicting postnatal CoA was then assessed.

Of the 83 fetuses referred for suspected CoA, 30 (36.1%) had confirmed CoA postnatally. The sensitivity and specificity for antenatal diagnosis were 83.3% (95% confidence interval [CI]: 65.3-94.4%) and 45.3% (95% CI: 31.6-59.6%), respectively. Neonates with confirmed CoA had lower mean AV Z-scores (-2.1 vs. -1.1, p = 0.01), higher PV Z-scores (1.6 vs. 0.8, p = 0.03), and a lower AV/PV ratio (0.5 vs. 0.6, p < 0.001). Subjective assessments of symmetry and the incidence of persistent left superior vena cava did not differ between groups. Among the variables studied, the most promising marker for CoA was the AV/PV ratio (area under the receiver operating characteristics curve 0.81, 95% CI: 0.67-0.94).

The use of objective sonographic markers, in particular measurements of the AV and PV, shows a trend toward an improvement in prenatal detection of CoA. Confirmation in larger studies is required.