Risk Factors for Coarctation of the Aorta on Prenatal Ultrasound: A Systematic Review and Meta-Analysis.

BACKGROUND

Prenatal diagnosis of coarctation of the aorta (CoA) is still challenging and affected by high rates of false-positive diagnoses. The aim of this study was to ascertain the strength of association and to quantify the diagnostic accuracy of different ultrasound signs in predicting CoA prenatally.

METHODS

Medline, Embase, CINAHL, and Cochrane databases were searched. Random-effects and hierarchical summary receiver operating characteristic model meta-analyses were used to analyze the data.

RESULTS

Seven hundred ninety-four articles were identified, and 12 (922 fetuses at risk for CoA) articles were included. Mean mitral valve diameter score was lower (<0.001) and the mean tricuspid valve diameter score was higher in fetuses with CoA than in those without CoA (=0.01). Mean aortic valve diameter score was lower in fetuses with CoA than in healthy fetuses (≤0.001), but the ascending aorta diameter, expressed as score or millimeters, was similar between groups (=0.07 and 0.47, respectively). Mean aortic isthmus diameter scores measured either in sagittal (=0.02) or in 3-vessel trachea view (<0.001) were lower in fetuses with CoA. Conversely, the mean pulmonary artery diameter score, the right/left ventricular and pulmonary artery/ascending aorta diameter ratios were higher (<0.001, =0.02, and =0.02, respectively) in fetuses with CoA in comparison with controls, although aortic isthmus/arterial duct diameter ratio was lower in fetuses with CoA than in those without CoA (<0.001). The presence of coarctation shelf and aortic arch hypoplasia were more common in fetuses with CoA than in controls (odds ratio, 26.0; 95% confidence interval, 4.42-153; <0.001 and odds ratio, 38.2; 95% confidence interval, 3.01-486; =0.005), whereas persistent left superior vena cava (=0.85), ventricular septal defect (=0.12), and bicuspid aortic valve (=0.14) did not carry an increased risk for this anomaly. Multiparametric diagnostic models integrating different ultrasound signs for the detection of CoA were associated with an increased detection rate.

CONCLUSIONS

The detection rate of CoA may improve when a multiple-criteria prediction model is adopted. Further large multicenter studies sharing the same imaging protocols are needed to develop objective models for risk assessment in these fetuses.