Fetal Left Cardiac Function Assessed With Four-dimensional Ultrasound Imaging Using Spatiotemporal Image Correlation

Objective:The objective of this study was to quantify fetus left ventricular volume between22-39weeks in normal and pathologic states with the spatiotemporal image correlation(STIC)and virtual organ computer-aided analysis(VOCAL).To establish the relation between the normal fetal left ventricular volume and gestation, estimate the left heart’s function by calculate fetal cardiovascular parameters. In addition we analysis fetal ventricular volume in pathologic states to discuss the feasibility and accuracy of STIC estimate the deformed fetal heart volume.Study design:This study successful gathered251women’s ven-tricular volume datasets (22-39weeks of gestation) using the STIC ultrasound technique.244fetuses are normal and7fetuses are abnor-mal. The inclusion criteria for normal team were uncomplicated sin-gleton pregnancy with normal fetal anatomy and growth demonstrat-ed by ultrasound examination, and gestational age defined by a kn-own date of last menstrual period and confirmed by fetal biometric measurements(HC,AC,FL).The abnormal fetuses were diagnosed duri-ng the study period with a cardiac anomaly were examined, and th-ose results were demonstrated by dissection or postnatal examinationThe volume datasets were gathered during fetal quiescence with abdomen uppermost. Cardiac ventricular volumes were calculated in VOCAL Ⅱ.We identify end-systole and end-diastole by scrolling thr-ough each frame and identifying the image preceding the AV valve opening (systole) and following AV valve closure(diastole).The inner contour of left ventricular in12planes were drawn manually, Then a volume was computed.The volume datasets were used to calculate stroke volume(SV),cardiac output(CO),and ejection fraction(EF).This study adjusted CO by the estimated fetal weight (EFW),HC,AC,FL and analysis the relation between all parameters and gestation. Result:The result made from the normal team were:1) left v-entricular volume(both systole and diastole), SV,CO increased with a-dvancing gestational age (p<0.05);2) cardiac output adjusted by fet-al biometric parameters (CO/HC,CO/AC,CO/FL) increased with adv-ancing gestational age(p<0.05);3) There are no correlation between fetal ejection fraction and gestational age (adjusted R2=0.024, p<0.05),the95%distribution:68.71±6.00%;4) During our study, we found that there are no correlation between fetal cardiac output per unit estimated fetal weight and gestational age(adjusted R2=0.032,p<0.05), the95%distribution:124.18±23.70ml/min/kg.In the abnormal team, the left ventricular volume(both systole and diastole) of3Intrauterine growth restriction(HLHS),1aortic valve stenosis and1Foramen Oval reception were decreased, and lower than two times standard difference of same gestation normal measured values. For fetus who have hypoplastic right ventricle, pulmonary valve malfunction, they left ventricular volume were higher than two times standard difference of same gestation normal measured values.Conclusions:1) fetal left ventricular volume (both systole and diastole),SV,CO increased with advancing gestational age.2) cardiac output adjusted by fetal biometric parameters(CO/HC,CO/AC,CO/FL) increased with advancing gestational age.3) There are no correlation between fetal ejection fraction or cardiac output per unit of estimate-d fetal weight and gestational age.4)STIC not only can detect the abnormal of fetal heart, but also can estimate ventricular volume in both normal and pathologic states accurately. It also prompt the ch-ange of heart function.This study established reference intervals for fetal left ventricular function parameters. The describe of abnormal fetal hearts’volume and function provides reference material for dis-cuss left ventricular function in pathologic states in the future.