Evaluation Of Ventricular Function In Fetuses With Gestational Diabetes Mellitus In The Second Trimester Using Multiple Parameters Of Echocardiography

Objective:Gestational diabetes mellitus（GDM）refers to diabetes that occurs for the first time in pregnant women during pregnancy.Due to the susceptibility brought about by metabolic changes in the second trimester and the increasing number of pregnant women with obesity and advanced maternal age,the incidence of GDM remains high.GDM affects the health of the pregnant woman and the fetuses,including the structure and function of the fetal heart.Animal studies have shown that exposure to intrauterine hyperglycemia may cause abnormal glucose metabolism and lipid metabolism in the fetal mice,which may cause excessive production of reactive oxygen species and subsequent oxidative stress.Further,it has been reported that reactive oxygen species can directly damage the systolic function of the heart.Excessive glucose may cause fetal hyperinsulinemia,which may lead to a decrease in fetal blood oxygen levels.Fetal hypoxia is accompanied by a surge in the levels of adrenaline and catecholamines,which cause heart remodeling and hypertrophy,resulting in abnormal fetal cardiac function.This study aims to evaluate the effects of GDM on fetal cardiac morphology and function using ultrasonic multiple parameters,and to evaluate its relationship with maternal age（MA）,body mass index（BMI）,estimated gestational age（EGA）,and glycosylated hemoglobin（Hb A1c）.Methods:This single-center prospective observational cohort study included 62fetuses of mothers with GDM as the case group and another 30 matched fetuses of mothers with normal pregnancies as the control group.Gestational age was finally corrected as 24⁺⁰–27⁺⁶weeks.And the pregnant women in the control group are similar in age to the GDM group.Cases and controls were recruited from January2020 to October 2020 at the Department of Ultrasound,Shengjing Hospital of China Medical University,Shenyang,China.The study was approved by the ethics committee of Shengjing Hospital,and all pregnant women signed an informed consent form for voluntary participation in the study.The overall condition of the fetuses was evaluated first.The mitral and tricuspid inflow velocities and their ratio（Mitral E,Mitral A,Mitral E/A,Tricuspid E,Tricuspid A,Tricuspid E/A）were measured sequentially.Isovolumic contraction time（IVCT）,isovolumic relaxation time（IVRT）,Ejection time（ET）,and myocardial performance index（MPI）were measured by tissue Doppler.Using the GE automatic fetal heart assessment tool（Fetal HQ）to measure the global sphericity index（GSI）,global longitudinal strain（GLS）,fractional area change（FAC）,24-segment end diastolic diameter（EDD）,24-segment sphericity index（SI）,24-segment fractional shortening（FS）.And then,the resistance index（RI）and pulsatility index（PI）of both maternal uterine artery（Ut A）,fetal middle cerebral artery（MCA）,and umbilical artery（UA）,aortic isthmus（Ao I）,pulmonary vein（PV）,ductus venosus（DV）should be measured.All data were tested for normal distribution,and the differences between the two groups were compared by t test.At the same time,Pearson correlation analysis and general linear regression analysis were performed between the main parameters and MA,BMI,EGA and Hb A1c to evaluate their correlation.The test level was statistically significant with P<0.05.Results:1.There were no statistical differences in Mitral E、Mitral A、Mitral E/A、Tricuspid E、Tricuspid A、Tricuspid E/A（P>0.05）between the GDM group and the control group.2.Compared with the control group,IVCT、IVRT and MPI of the both ventricles of GDM fetuses were decreased（P<0.05）.3.Compared with the control group,the GSI、GLS and FAC of the GDM fetuses were decreased（P<0.05）.4.There was a positive linear correlation between LV-MPI and EGA in GDM fetuses（r=0.051,P=0.047）.And RV-FAC was negatively linearly correlated with maternal BMI in the GDM group（r=-0.278,P<0.05）.5.Compared with traditional cardiac ultrasonic parameters,Fetal HQ can provide morphological and functional parameters at the same time,which can comprehensively and quantitatively evaluate the changes of the fetal heart.6.Compared with other manufacturers’speckle tracking technology,Fetal HQ only requires a standard"four-chamber heart"view,which is very easy to obtain and reduces the difficulty of operation and shortens the operation time.Conclusions:1.Fetal cardiac morphology and function can be changed by GDM,which is closer to"spherical"in the shape.And ultrasound can be used to evaluate these changes.2.The spectrum of mitral and tricuspid valve and some related vascular blood flow cannot evaluate the changes of fetal cardiac function early and sensitively.3.Compared with the control group,IVCT、IVRT、MPI of GDM fetuses increased while GSI、GLS and FAC of both ventricles of GDM fetuses decreased,which indicated an impaired function of GDM fetuses.4.LV-MPI showed a positive linear correlation with EGA in the GDM group,while RV-FAC showed a negative linear correlation with maternal BMI in the GDM group.However,Hb A1c has a poor correlation with the main parameters.5.Fetal HQ is a new technology,it can easily and quickly assess fetal cardiac morphology and function,which can improve the feasibility and reproducibility.