Myocardial performance index in fetal anemia

Is It Diabetes or Just Macrosomia? Fetal Myocardial Performance Index in Large-for-Gestational Age Fetuses

Our aim in this study was to investigate whether there is an association between large-for-gestational age (LGA) fetuses and myocardial performance index (MPI). This is a cross-sectional study conducted from July 2022 to July 2023. Prospectively gathered data from 65 LGA cases and 65 age and gestational-age (GA)-matched controls were analyzed. Presence of polyhydramnios and diabetes were recorded in the study group. Fetal left ventricular mod-MPI, peak systolic velocity (PSV) of E and A waves, umbilical and middle cerebral artery (MCA) pulsatility indexes (PI) were sonographically measured. Association between these sonographic measures and LGA fetuses were sought. The LGA group had 33 diabetic cases (22 GDM and 11 PGDM). The LGA group had greater mod-MPI (0.51 vs. 0.45, p = 0.0048). The LGA group also had prolonged isovolumetric contraction time (ICT), compared to controls (37 ms vs. 33 ms, p = 0.008). ICT was longer in LGA fetuses with non-diabetic mothers (38 ms vs. 33 ms, p = 0.009). LGA fetuses with polyhydramnios but without diabetic mothers had also longer ICT (39 ms vs. 33 ms, p = 0.002). Mod-MPI was similar in controls and LGA without diabetes/LGA with polyhydramnios but without diabetes subgroups. Our results indicate that fetal mod-MPI values are higher in LGA fetuses and ICT is prolonged among LGA fetuses irrespective of presence of maternal diabetes.

Reference ranges of fetal heart function using a Modified Myocardial Performance Index: a prospective multicentre, cross-sectional study

OBJECTIVES

The primary aim of this study was to establish the normal reference ranges of the fetal left ventricular (LV) Modified Myocardial Performance Index (Mod-MPI). A secondary aim was to evaluate the agreement between manual and automatic measurements for fetal Mod-MPI.

DESIGN

A prospective, multicentre, cross-sectional study.

PARTICIPANTS

Normal singleton pregnancies.

METHODS

The LV functions of normal singleton pregnancies were assessed in nine centres covering eight provinces in China using unified ultrasound protocols and settings and standardised measurements by pulsed Doppler at 20-24, 28-32 and 34-38 weeks of gestation. The isovolumetric relaxation time (IRT), isovolumetric contraction time, ejection time (ET) and Mod-MPI were measured both automatically and manually.

RESULTS

This cross-sectional study included 2081 fetuses, and there was a linear correlation between gestational age (GA) and Mod-MPI (0.416+0.001×GA (weeks), p<0.001, r²=0.013), IRT (36.201+0.162× GA (weeks), p<0.001, r²=0.021) and ET (171.418-0.078*GA (weeks), p<0.001, r²=0.002). This finding was verified using longitudinal data in a subgroup of 610 women. The agreement between the manual and automated measurements for Mod-MPI was good.

CONCLUSIONS

We constructed normal reference values of fetal LV Mod-MPI. Automatic measurement can be considered for ease of measurement in view of the good agreement between the automatic and manual values.

Assessment of fetal right ventricular myocardial performance index changes following intrauterine transfusion

INTRODUCTION

Severe fetal anemia may cause cardiac ischemia, reduced contractility, and dysfunction. The purpose of our study is to evaluate right ventricular myocardial performance index (MPI) before and after intrauterine transfusion (IUT) in patients who underwent this procedure because of fetal anemia due to Rh-D alloimmunization.

MATERIALS AND METHODS

This prospective cohort study was conducted between January 2018 and June 2019 at Kanuni Sultan Suleyman Research and Training Hospital, Istanbul, Turkey. The pregnant women who were applied IUT because of fetal anemia due to Rh-D alloimmunization in our perinatology clinic were included in the study. Fetal right ventricular MPI before and 24 h after IUT were evaluated.

RESULTS

A total of 28 IUTs were performed in 17 pregnant women during the study period. The isovolumetric contraction time (ICT) and isovolumetric relaxation time (IRT) values measured before IUT, were found to be significantly longer compared to the ICT and IRT values measured after IUT. The MPI values measured after transfusion was found to be higher than before transfusion.

CONCLUSIONS

The fetal right ventricular MPI increases 24 h after IUT. This increase in the right ventricular MPI might be used as a marker for predicting adverse fetal outcomes following IUT.

Time Interval Measurements of the Ductus Venosus During the Early Second Trimester of Pregnancy: Reference Ranges and Clinical Application

OBJECTIVES

The aims of this study were to construct reference ranges for the time interval parameters of the ductus venosus during the early second trimester of pregnancy and to demonstrate the clinical utility in various fetal disorders.

METHODS

The ductus venosus Doppler measurements of 331 healthy fetuses between 15 and 22 weeks' gestation were analyzed. The systolic time and diastolic time were subdivided into the systolic acceleration time, systolic deceleration time, diastolic acceleration time, and diastolic deceleration time. The median, 5th, and 95th regression lines for each variable were determined according to gestational age. The ductus venosus time interval parameters in cases of fetoplacental abnormalities were calculated and plotted against the reference ranges.

RESULTS

With advancing gestation, the systolic acceleration time and total systolic time increased significantly (P < .001). In contrast to the systolic phase, the diastolic deceleration time decreased significantly during the early second trimester of pregnancy (P = .023). The systolic deceleration time, diastolic acceleration time, and diastolic time were relatively constant. Fetuses with tricuspid insufficiency, twin-twin transfusion syndrome, intrauterine fetal growth restriction, and anemia had abnormal ductus venosus times with different patterns.

CONCLUSIONS

Predicted normal reference ranges for time interval variables in relation to gestational age were established. These could be helpful for assessing fetal cardiovascular function during the early second trimester of pregnancy.

Fetal isovolumetric time intervals as a marker of abnormal cardiac function in fetal anemia from homozygous alpha thalassemia-1 disease

OBJECTIVE

To determine whether fetal isovolumetric time intervals can be an early sonographic marker of fetal anemia in fetuses with homozygous alpha thalassemia-1.

METHODS

Pregnancies at risk for fetal homozygous alpha thalassemia-1 disease at 18-22 weeks were recruited before cordocentesis for hemoglobin typing. Isovolumetric contraction time (ICT) and isovolumetric relaxation time (IRT) intervals were measured by placing pulsed wave Doppler sample volume within the left ventricle to obtain the mitral and aortic waveform. Time intervals were compared between the affected group of homozygous alpha thalassemia-1 fetuses and the unaffected group.

RESULTS

Among 70 fetuses at risk, 28 cases were diagnosed as affected by homozygous alpha thalassemia-1 disease. Mean ICT and ICT + IRT intervals in the affected group were significantly longer than in the unaffected group (47.9 ± 12.5 ms vs 35.0 ± 6.7 ms, p < 0.001; and 96.2 ± 13.6 ms vs 80.9 ± 10.6 ms, p < 0.001. ICT effectively predicted affected fetuses with 71.4% sensitivity and 78.6% specificity using a cutoff value ≥40 ms.

CONCLUSIONS

Isovolumetric contraction time was significantly prolonged in fetal anemia from homozygous alpha thalassemia-1 during the early stage of hydropic changes. Because of its simple measurement and high efficacy, ICT can be a useful marker for prenatal screening of abnormal cardiac function in fetal anemia. © 2017 John Wiley & Sons, Ltd.

Fetal myocardial index during labor

BACKGROUND: The Myocardial Performance Index (MPI) is a Doppler derived myocardial function tool and can be used to evaluate systolic and diastolic function in fetuses. The objectives of this study were to investigate the MPI during labor and compare it to values in non-laboring women.

METHODOLOGY: 40 women with uncomplicated, term, singleton pregnancies were recruited to this prospective observational study at Thomas Jefferson University Hospital. Controls were a retrospective cohort of women > 34 weeks who underwent third trimester fetal echocardiography. Fetal left and right sided isovolumic contraction time, isovolumic relaxation time and ejection time were recorded before, during and after contractions. Right and left sided MPI was then calculated.

RESULTS: Laboring patients and non-laboring patients were comparable for age, race, gravidity and parity. During labor the average left MPI was 0.63 ± 0.17 and the average right MPI was 0.62 ± 0.20. The coefficient of correlation between MPI and cervical dilation was 0.15 for left MPI Index and 0.14 for right MPI. When comparing non-laboring to laboring women, the average left MPI for non-laboring women was 0.34 ± 0.04, p = <0.001.

CONCLUSIONS: Myocardial Performance Index is a non-invasive, easily attainable measure of cardiac function that can be obtained during labor and does not change with cervical dilation. MPI is significantly different between laboring and non-laboring women. The fetal MPI may help define fetal status in labor.

Changes in fetal myocardial performance index following intravascular transfusion: preliminary report

OBJECTIVE

To investigate the changes in fetal left ventricle myocardial performance index (MPI) following intrauterine intravascular transfusion (IUT).

METHODS

Prospective study, including 25 IUT performed in 13 singleton pregnancies with maternal Rh D alloimmune disease. Left ventricle MPI was evaluated prior to transfusion and repeated 24 h after each procedure. Delta MPI was calculated as the difference between post- and pre-transfusion MPI z-scores. Multilevel regression analysis was used to examine the association between delta MPI and gestational age at procedure, fetal middle cerebral artery peak velocity MoM, pre- and post-MPI and hemoglobin z-score values, the volume of blood transfused and feto-placental volume percentage expansion. Adjustments were made for repeated measurements within the same fetus, and across different time points. The significance level was set as 0.05.

RESULTS

MPI z-score values increased significantly following transfusion (delta MPI = 1.10 ± 2.47, p=0.036). Delta MPI showed a significant correlation with gestational age at transfusion (r= -0.47, p=0.018), pre-transfusion MPI z-score (r= -0.50, p=0.012) and feto-placental volume percentage expansion (r= -0.41, p=0.044).

CONCLUSION

Left ventricle MPI increases significantly after intrauterine blood transfusion and greater changes are associated with procedures at an earlier gestational age, lower pre-transfusion MPI z-scores and smaller feto-placental volume expansion.