EP09.81: A study of the value of applying Slowflow and increasing outflow tract coronal sections in cardiac screening in the first trimester

To improve the diagnostic rate of congenital heart disease in the first trimester, the reproducibility and effectiveness of the new combined method were investigated by using slowflow to display outflow coronal section blood flow images on the basis of conventional screening methods. Fetal ultrasound images of NT screening during the first trimester were collected from 2020 to 2023 at the Peking University First Hospital Ningxia Women and Children's Hospital (Ningxia Hui Autonomous Region Maternal and Child Health Hospital). The fetuses were followed up during pregnancy or postnatal cardiac examination, and the fetuses were divided into normal cardiac structure group and abnormal group, and fetal autopsy was performed after informed consent in some groups with abnormal labour induction. The sensitivity and specificity of this method in diagnosing the structural normality of the fetal heart in the first trimester were statistically analysed. A total of 1131 pregnant women were included in the statistics, including 143 children with CHD, 129 cases were detected in the first trimester, 27 cases were missed, 13 cases were misdiagnosed, and 156 cases were induced. The positive diagnosis rate was 90.21%, and the positive incidence rate was 12.64%. The sensitivity of conventional screening combined with slowflowHD and scanning the outflow tract coronal section in the first trimester were 81.21%, 98.68%, AUC = 0.90, 61.65 and 0.19, and the disease prevalence was 13%, 90.21% and 97.22% respectively. The conventional screening method combined with slowflowHD and the scanning of the outflow tract coronal section in the first trimester have high screening and diagnostic value for fetal cardiac macrovascular malformations, which can be used as a new combined diagnostic method for cardiac screening in the first trimester and a new diagnostic mode for CHD.