Abstract:

Objective

To evaluate the value of fetal heart quantitation （fetal HQ） combined with other multiple fetal echocardiographic quantitative parameters in evaluating heart structure and function in fetuses with coarctation of the aorta （CoA）.

Methods

Fifty fetuses suspected of having CoA who underwent fetal echocardiography at the Department of Diagnostic Ultrasound & Echocardiography， Sir Run Run Shaw Hospital， Zhejiang University College of Medicine from January 2022 to January 2023 were selected as the study subjects. The fetuses diagnosed with CoA in the outpatient follow-up after delivery were included in a CoA group （18 cases）， and those with false-positive results as demonstrated during outpatient follow-up were included in a control group （32 cases）. Overall cardiovascular parameters of the two groups of fetuses were compared， including left ventricular fractional area change （LVFAC）， LVFAC Z-score， left ventricular global longitudinal strain （LVGLS）， right ventricular global longitudinal strain （RVGLS）， right ventricular area （RVA）/left ventricular area （LVA） ratio， aortic isthmus inner diameter （AI） and its Z score （AI Z-score），aortic isthmus inner diameter/descending aorta inner diameter ratio （AI/DAO ratio）， main pulmonary artery inner diameter/ascending aorta inner diameter ratio （MPA/AAO ratio）. The end diastolic transverse diameter（ED）， ED Z-score， short axis shortening rate （FS）， FS Z-score， sphericity index （SI）， and SI Z-score of the 24 segments of the left and right ventricle were also compared between the two groups. Multivariate Logistic regression analysis was performed to identify risk factors for CoA. Receiver operating characteristics（ROC） curve analysis was performed to test the diagnostic efficacy of LVFAC， LVFAC Z-score， AI， and the combination of the three for fetal CoA. Within-group correlation coefficients （ICCs） were used to judge the consistency of measured parameters within and between observers.

Results

LVFAC， LVFAC Z-score，LVGLS， RVGLS， AI， AI Z-score， and AI/DAO ratio were significantly lower in the CoA group than in the control group， while RVA /LVA ratio and MPA/AAO ratio of fetuses in the CoA group were significantly higher than those of the control group （P＜0.05）. The ED Z-score of the first segment of the left ventricle in the CoA group was significantly lower than that of the control group （P＜0.05）， and the FS Z-scores of the fourth to eighth segments of the left ventricle were significantly higher than those of the control group （P＜0.05）. LVFAC， LVFAC Z-score， and AI were identified to be risk factors for CoA （P＜0.05）. The area under the ROC curve values of LVFAC， LVFAC Z-score， AI， and their combination for diagnosing fetal CoA were 0.989 （0.969 ～ 1.000）， 0.966 （0.922 ～ 1.000）， 0.785 （0.731 ～ 0.859）， and 0.997 （0.987 ～ 1.000），respectively. The ICCs for intra-observer and inter-observer measurements of various fetal parameters ranged from 0.90 to 0.99.

Conclusion

Fetal HQ combined with other multiple fetal echocardiographic quantitative parameters can effectively evaluate the changes of heart structure， size， and function in fetuses with CoA，providing reference information for improving prenatal detection of CoA.

Key words: Fetus, Coarctation of the aorta, Fetal heart quantification, Echocardiography, Congenital heart disease