Research on relevant factors and the value on prenatal ultrasound diagnosis for coarctation of the aorta

Abstract

Objective To improve the accuracy of prenatal diagnosis for coarctation of the aorta(CoA) by comparatively analyzing the relevant factors and their application value. Methods Cases of disproportion of ventricles and great vessels were selected between January 2011 and July 2018. Only liveborn fetuses with complete postnatal follow-up were included in the study. One hundred and twelve cases were retrieved and analyzed. According to the postnatal ultrasound and CT results, the patients were divided into gruop A and goup B. Different fetal echocardiography parameters and features were selected to evaluate the diagnostic value. Logistic regression analysis was used to select the best predictors of CoA and optimal cut-offs for these parameters were identified by ROC analysis. Results One hundred and thirty eight fetuses were suspected to be CoA, and 112 of them were born. They included 59 cases (52.9%) with CoA(Group A) and 53 cases (47.3%) without CoA(Group B). There were statistically significant differences between the two groups in gestational age, Z-score of diameter of left ventricle, ascending aorta (AAO) and aortic arch isthmus, main pulmonary artery (MPA)/AAO diameters ratio, and arterial duct/isthmus diameters ratio. The parameters most predictive of postnatal CoA selected by logistic regression and the cut-off values identified by ROC analysis were: gestational age at first diagnosis ≤34.5 weeks, Z-score of diameter of left ventricle 1.6. AUC yielded by these parameters in combination was 0.94(95%CI: 0.89-0.99). The study group were divided into two subgroups by gestational age at first diagnosis.The parameters and cut-off values in subgroups were selected by the same analysis as above: Group Ⅰ(≤34.5 weeks), Z-score of diameter of right ventricle >2.1, MPA/AAO diameters ratio>1.6; Group Ⅱ(>34.5 weeks), MPA/AAO diameters ratio>1.7, arterial duct/isthmus diameters ratio>2.3. Meanwhile, some ultrasound features(including aortic arch hypoplasia, retrograde blood flow of aortic isthmus) should also be considered to improve diagnostic accuracy. Conclusions Combined with the use of different ultrasound parameters and features at different gestational weeks can improve the accuracy of the prenatal diagnosis of CoA in the right heart dominant fetus. Key words: Echocardiography; Fetal; Congenital heart disease; Aorta coarctation