Evaluation Of Fetal Cardiac Valves By Real-time 4D Volume Imaging With Electronic Matrix Probe

Objective: Valve dysplasia is a common congenital heart malformation.As an important anatomical structure connecting cardiac cavities and the great blood vessels,the valve has important hemodynamic significance.Valve abnormalities can cause stenosis,regurgitation,and even secondary changes such as volume load in severe cases.The real-time four-dimensional(RT 4D)volume imaging technology with electronic matrix probe is a new type of real-time ultrasound imaging technology,which can display the three-dimensional anatomical structure and morphology of the fetal cardiac valves in real-time and dynamically from multiple angles.This study aims to explore the clinical application and diagnostic value of RT 4D volume imaging technology with electronic matrix probe in the observation of normal and abnormal fetal cardiac valves.Methods: 154 normal fetuses and 18 fetuses with valve malformations underwent fetal cardiac examination in the ultrasound department of Shengjing Hospital of China Medical University from July 2019 to November 2020 were collected for statistical analysis.The RT 4D volume imaging technology with electronic matrix probe was used to collect the fetal heart volume data of the normal group and reconstruct the fetal heart valves(mitral valve,tricuspid valve,aortic valve,pulmonary valve)in real-time,and calculated the display rate of each valve structure.This technology was also used to measure the mitral/ tricuspid annulus area of normal fetuses in different gestational weeks at the end of diastole simultaneously.Results: The RT 4D volume imaging technology with electronic matrix probe can facilitate the visualization of the fetal heart valves structure.In normal fetuses,the rate of visualization of cardiac valves in 22-28 gestational weeks is 97.4%,93.1%,86.2%,80.2%(mitral valve,tricuspid valve,aortic valve,pulmonary valve),respectively.And in29-32 gestational weeks is 92.1%,89.5%,81.6%,71.1%(mitral valve,tricuspid valve,aortic valve,pulmonary valve),respectively.The mitral and tricuspid valve annulus area were positively correlated with gestational age at the end of diastole(P<0.05).In addition,in 16/18(88.9%)fetuses with heart valve diseases were obtained the 4D rendered images successfully.Conclusion: 1.The RT 4D volume imaging technology with electronic matrix probe can display the structure of the cardiac valves of normal and abnormal fetuses in real-time,including some anatomical and pathological information which can not be recognized by conventional two-dimensional echocardiography(2DE).2.The application of RT 4D volume imaging technology with electronic matrix probe can determine the reference range of the atrioventricular valve annulus area of normal fetuses at different gestational weeks and provide the certain diagnostic valve for the clinic.