Determination of the myocardial performance index in deteriorating grades of intrauterine growth restriction and its link to adverse outcomes

Inclusion of Speckle Tracking Echocardiography Analysis in the Management of Intrauterine Growth Restrictions-Literature Review and Case Reports

Background/Objectives: The relationship between ultrasound parameters and fetal health in the context of intrauterine growth restriction (IUGR) pregnancies constitutes a significant focus of scholarly research. A comprehensive range of Doppler and echocardiographic evaluations, encompassing the umbilical artery, middle cerebral artery, ductus venosus, uterine arteries, cardiac contractility, ventricular filling, and the thickness of the interventricular septum, has been proposed in pathological pregnancies. Methods: The aim of this paper is to present an examination of these metrics and their implications for fetal health within the framework of IUGR pregnancies and to report a case series in which we analyzed the correlation of these factors. The assessment of these ultrasound indicators can help in better management of the cases in order to obtain better fetal outcomes. Results: Our case study presented dynamics corelated to the after-birth evaluation of the neonate, reflecting the importance of complete ultrasound assessment in high-risk cases. Conclusions: Speckle tracking echocardiography has significantly advanced our understanding of cardiac function in IUGR fetuses. As shown in our cases, it can be used to detect early signs of cardiac dysfunction, differentiating between FGR and SGA.

Fetal epicardial fat thickness and modified myocardial performance index in late-onset fetal growth restriction

AIM

In our study, we aimed to investigate the value of fetal epicardial fat thickness (EFT) and modified myocardial performance index (mod-MPI) in fetal growth restriction (FGR) that develops after the 32nd week of gestation.

MATERIALS AND METHODS

Fifty-six pregnant women who met the inclusion and exclusion criteria were included in the study and were divided into two groups: pregnancies diagnosed with FGR after the 32nd week of gestation (FGR group) and those without (control group). Demographic and obstetric histories, ultrasonographic and clinical characteristics, fetal EFT and mod-MPI values, and neonatal outcomes of the groups were recorded, and comparisons were made between the groups. Additionally, the diagnostic performance of fetal EFT value in late FGR was investigated.

RESULTS

The FGR group had fetal EFT that was statistically significantly lower (1.11 ± 0.21 vs. 1.34 ± 0.23, p = 0.001). The FGR group had a significantly lower isovolumetric contraction time (ICT) (31.04 ± 6.88 vs. 35.14 ± 7.58, p = 0.048). The two groups' isovolumetric relaxation time (IRT), ejection time (ET), and mod-MPI values (p values 0.871, 0.55, and 0.750, respectively) were comparable. Receiver operating characteristic (ROC) analysis at a cutoff of 1.2 revealed 76.1% sensitivity and 74.2% specificity, respectively, for the diagnostic performance of the fetal EFT value in late-onset FGR. There was a positive predictive value (PPV) and negative predictive value (NPV) of 64.0% and 83.8%, respectively.

CONCLUSION

We found that fetal EFT was significantly lower in FGR and may be useful in diagnosing FGR. However, we observed that mode-MPI did not change in FGR.

Using Doppler ultrasound to assess fetal cardiac function and pregnancy outcomes in obstetric antiphospholipid syndrome pregnancies: a case-control study

PURPOSE

This study aimed to evaluate fetal left ventricular function (LVF) in pregnant women with obstetric antiphospholipid syndrome (OAPS) by Doppler ultrasound and developed a clinical nomogram to predict adverse perinatal outcomes.

METHODS

In this prospective observational study, 105 pregnant women were enrolled and divided into the OAPS cohort (n = 60) and the control cohort (n = 45). Fetal cardiac function parameters were collected and compared between two cohorts. Univariate and multivariate analysis was conducted to select the risk factors associated with adverse perinatal outcomes, and a clinical nomogram was developed based on these selected risk factors. The predictive performance of corresponding indicators for adverse perinatal outcomes was evaluated using receiver operating characteristic (ROC) curve analysis.

RESULTS

The OAPS cohort revealed an increase in the isovolumic relaxation time (IVRT) and myocardial performance index (MPI), a decrease in the ejection time (ET), middle cerebral artery pulsatility index (MCA-PI) and cerebroplacental ratio (CPR) compared to the control cohort. Through univariate and multivariate analysis, gravidity, CPR, and MPI were the risk factors associated with adverse perinatal outcomes. A model predicting adverse perinatal outcomes in OAPS pregnant women was constructed based on these three factors and visualized as a nomogram. The nomogram could accurately predict adverse perinatal outcomes with an area under the curve of 0.923 (95% CI: 0.858-0.982). This performance was better than evaluating individual factors such as MPI (0.825, 95% CI: 0.739-0.911) and CPR (0.816, 95% CI: 0.705-0.927) for efficacy.

CONCLUSION

MPI can be used to assess fetal LVF and predict adverse perinatal outcomes. We developed a nomogram to predict adverse perinatal outcomes in OAPS women. This imaging-based evidence can provide timely clinical intervention, enabling personalized clinical decision-making.

Effect of abnormal placentation on fetal heart function and neonatal outcomes

OBJECTIVE

This study aimed to investigate the fetal modified (mod)-myocardial performance index (MPI) for fetal cardiac function in placenta percreta (PPC) pregnancies with placenta previa (PP) and assess neonatal outcomes.

MATERIALS AND METHODS

This study included 104 pregnant women: 52 with PPC and 52 as the control group. Mod-MPI measurements and neonatal outcomes were evaluated in all cases.

RESULTS

The PPC group had a significantly lower left ejection time (p = 0.044) and significantly higher mod-MPI (p = 0.001) than the control group. The optimal mod-MPI predictive cut-off value at the neonatal intensive care unit (NICU) admission in the PPC group was 0.53 with 53.8% specificity and 88.5% sensitivity (p = 0.019). The optimal mod-MPI predictive cut-off value at the 5th APGAR score below 7 in the PPC group was 0.55 with a specificity of 67.7% and a sensitivity of 76.2% (p = 0.016).

CONCLUSION

Fetal MPI was higher in pregnant women with PPC compared to the control group. Among the PPC cases, those with MPI above a certain predictive level showed more frequent NICU admissions and lower APGAR scores.

The Significance of the Myocardial Performance Index and Fetal Doppler Abnormalities in Growth-Restricted Fetuses: A Systematic Review of the Literature

Introduction: This review aims to investigate the clinical implications of using the myocardial performance index (MPI), obtained through tissue Doppler imaging (TDI) and spectral Doppler, in assessing fetal cardiac function in growth-restricted fetuses. It explores the MPI's potential in predicting adverse perinatal outcomes and its utility when combined with conventional pulsed-wave Doppler assessments for enhanced fetal well-being evaluations. Material and Methods: A systematic search of PubMed and Google Scholar databases spanning from 2004 to 2023 was conducted to identify pertinent articles on the MPI's clinical application in managing growth-restricted fetuses. Inclusion criteria followed the Fetal Medicine Barcelona definition of fetal growth restriction (FGR) to mitigate study group heterogeneity. The research sources were PubMed and Google Scholar databases, and the review was conducted without any specific clinical or laboratory setting. Only articles meeting the inclusion criteria for FGR, as per the Fetal Medicine Barcelona definition, were considered. Six studies meeting these criteria were included in the review. The review analyzed the correlation between MPI values and conventional Doppler parameters, investigating the progression of myocardial function impairment and its association with the risk of fetal demise. The primary outcome measures included the relationship between MPI values, fetal well-being, and the potential for prenatal cardiac dysfunction in growth-restricted fetuses. Results: The findings indicate that as conventional Doppler parameters deteriorate, MPI values increase, suggesting progressive myocardial dysfunction. The MPI may cross the 95th percentile before abnormal flow in the ductus venosus and aortic isthmus, highlighting the potential for diastolic dysfunction preceding hypoxia in growth-restricted fetuses. Elevated MPI levels were observed in both growth-restricted and small-for-gestational-age (SGA) fetuses, indicating prenatal cardiac impairment. The strong association between an abnormal MPI and perinatal mortality has been shown for early FGR. Conclusions: MPI alterations appear to precede abnormal Doppler parameters in early- and late- onset FGR, potentially indicating diastolic dysfunction preceding hypoxia. Additionally, the MPI correlates with the risk of fetal demise. However, larger studies are needed to establish its sensitivity and specificity. Furthermore, the significance of prenatal cardiac impairment in some SGA fetuses raises questions about its potential impact on perinatal outcomes and cardiovascular programming.

Ductus arteriosus diameters in fetuses with early- and late-onset fetal growth restriction

PURPOSE

Fetal growth restriction (FGR) is a common pregnancy complication that can be associated with several adverse perinatal outcomes. One of these negative outcomes is ductus arteriosus, especially in preterm babies. In this study, intrauterine heart function and ductus diameter were evaluated in babies with FGR.

METHODS

Thirty-seven fetuses with FGR were compared with 37 normal-weight fetuses at the same gestational week. In our study, ventricular diameters, aorta, pulmonary artery, ductus arteriosus (DA), aortic arch diameter, and flow traces were examined. In addition, the aorta and aortic isthmus diameters were proportioned to the ductus diameter, and the left ventricular myocardial performance index (MPI) [(ICT + IRT)/ET] was evaluated.

RESULTS

There was no difference in DA diameters between the patient and control groups. The intragroup comparison of the cases with early- and late-onset FGR revealed no statistically significant difference between DA diameters. However, the ratios of the aortic annulus diameter/ductus diameter (AOD/DAD) and aortic isthmus diameter/ductus diameter (AID/DAD) were significantly lower in early-onset FGR because the diameter of the DA was greater. In addition, the mod-MPI values were higher in the patient group.

CONCLUSIONS

In our study, although the ductal diameters did not change significantly in the patient group, the ductal diameter was greater in the early-onset intrauterine growth restriction (FGR) group compared with other cardiac measurements. The mod-MPI value, a cardiac function indicator, was higher in fetuses with FGR. These findings may be useful for evaluating postnatal cardiac functions in FGR.

Evaluation of the fetal myocardial performance ındex and Epicardial fat thickness in pregnant women with preterm prelabor rupture of membranes

OBJECTIVE

To assess the epicardial fat thickness (EFT) and modified myocardial performance index (Mod-MPI) measurements in fetuses at pregnant women with preterm prelabor rupture of membranes (pPROM) and compare them to healthy pregnant women's fetuses.

METHODS

Forty patients who presented to our clinic at 24-36 + 6 gestational weeks and were diagnosed with pPROM were included in the patient group. During the same period, 40 healthy pregnant women at similar gestational weeks were randomly selected as the control group.

RESULTS

The pPROM and control groups were similar in terms of demographics. In the pPROM group, EFT, Mod-MPI, and isovolumetric contraction(ICT) and relaxation times(IRT) were significantly higher and ejection time (ET) was significantly lower compared to the control group. In addition, Mod-MPI z-scores, IRT z-scores, ICT z-scores were significantly higher and ET z-scores was significantly lower in the pPROM. According to the ROC analysis, the optimal cutoff value of EFT was calculated as 1.55 mm, with 68% sensitivity and 71% specificity (AUC: 0.718, 95% CI: 0.550-0.786, p = .018) for predicting NICU requirement and the optimal cutoff value of EFT was calculated as 1.55 mm with 72% sensitivity and 73% specificity (AUC: 0.726, 95% CI: 0.556-0.896, p = .015) for predicting medication use in the pPROM group.

CONCLUSION

This study revealed differences in the EFT and Mod-MPI measurements of the fetuses of pregnant women with pPROM. Considering that EFT is an important energy source for the myocardium, as well as an endocrine structure in which inflammatory and anti-inflammatory markers are secreted, it is recommended to be evaluated in inflammatory conditions such as pPROM.

Cardiac function evaluated by two-dimensional speckle tracking imaging in fetuses with congenital heart disease of ventricular afterload increase

AIMS

To study myocardial deformation in fetuses with ventricular afterload increase compared with gestational age-matched controls using speckle tracking echocardiography.

METHODS AND RESULTS

Eighty-nine fetuses were retrospectively selected from the pregnancy screen by echocardiography. There are 41 fetuses with gestational age-matched normal heart served as the control group, 25 fetuses with congenital heart disease (CHD) leading to left ventricular (LV) afterload increase as group LVA and 23 fetuses with CHD leading to right ventricular(RV) afterload increases as group RVA. LV and RV fractional shortening (FS) were measured by conventional methods. The longitudinal strain (LS) and strain rate (LSr) were analyzed by EchoPac software. Group LVA and RVA compared with control group, the LV FS was no significant difference, but LS and LSr values of LV were lower in fetuses with LVA compared to the control group (LS:-15.97(-12.50,-22.52)vs -27.53(-24.33,-29.16) %, p < .01; systolic strain rate (SRs):-1.34(-1.12,-2.16) vs -2.55(-2.28,-2.92) 1/sec, p < .01; early diastolic strain rate (SRe):1.70 ± 0.57 vs 2.46 ± 0.61 1/sec, p < 0.01; late diastolic strain rate (SRa):1.62 ± 0.82 vs 2.39 ± 0.81 1/sec, p < .01). LS and LSr values of LV or RV were lower in fetuses with RVA compared to the control group (LV: LS:-21.52 ± 6.68 vs -26.79 ± 3.22%, p < .01; SRs:-2.11 ± 0.78 vs -2.56 ± 0.43 1/sec; p = .02; RV: LS:-17.64 ± 7.58 vs -26.38 ± 3.97%, p < .01; SRs:-1.62 ± 0.67 vs -2.37 ± 0.44 1/sec; p < .01).

CONCLUSION

The results of this study showed that the ventricular LS, LSr, SRs, SRe, SRa values were lower in fetuses with LV or RV afterload increasing CHD estimated by speckle tracking imaging but LV and RV FS were normal,which indicated the strain imaging is feasible in evaluating cardiac function of fetus, and may be more sensitive.

Modified myocardial performance index for evaluation of fetal heart function and perinatal outcomes in intrahepatic pregnancy cholestasis

This study aims to evaluate cardiac function in cases of intrahepatic cholestasis of pregnancy (ICP) and compare results with those from healthy controls using the fetal left ventricular modified myocardial performance index (LMPI) and E-wave/A-wave peak velocities (E/A ratio). Moreover, the association between LMPI values, total bile acid (TBA) levels, fetal Doppler measurements, and adverse neonatal outcomes was evaluated. A prospective cross-sectional study of 120 pregnant women was conducted, with 60 having ICP and the other 60 serving as controls. Doppler ultrasound and two-dimensional gray-scale fetal echocardiography were used to calculate the LMPI values and E/A ratios, respectively. The association between LMPI values and TBA levels, fetal Doppler measurements, and adverse neonatal outcomes was evaluated. Fetal LMPI values were significantly higher in the ICP group than in the control group (0.54 ± 0.54 vs. 0.44 ± 0.03; p < 0.001), but the E/A ratio was similar in both groups (0.69 ± 0.10 vs. 0.66 ± 0.14; p = 0.203). TBA levels were positively and significantly correlated with LMPI values (r = 0.546, p < 0.01); however, no significant correlation was found between umbilical arterial pulsatility index values and LMPI values (r = 0.071, p > 0.01). LMPI values were not associated with adverse neonatal outcomes in ICP cases. Fetal cardiac function (LMPI) is associated with increased bile acid levels in ICP. However, because it was not associated with adverse neonatal outcomes in ICP cases, the clinical significance of this finding is unclear. Further studies are required to evaluate the implications of increased LMPI.

Progress of Pathogenesis in Pediatric Multifocal Atrial Tachycardia

Multifocal atrial tachycardia (MAT) is defined as irregular P-P, R-R, and P-R intervals, isoelectric baseline between P waves, and ventricular rate over 100 beats/min. Although the prognosis of pediatric MAT in most patients is favorable, adverse outcomes of MAT have been reported, such as cardiogenic death (3%), respiratory failure (6%), or persistent arrhythmia (7%), due to delayed diagnosis and poorly controlled MAT. Previous studies demonstrated that pediatric MAT is associated with multiple enhanced automatic lesions located in the atrium or abnormal automaticity of a single lesion located in the pulmonary veins via multiple pathways to trigger electrical activity. Recent studies indicated that pediatric MAT is associated with the formation of a re-entry loop, abnormal automaticity, and triggering activity. The occurrence of pediatric MAT is affected by gestational disease, congenital heart disease, post-cardiac surgery, pulmonary hypertension, and infectious diseases, which promote MAT via inflammation, redistribution of the autonomic nervous system, and abnormal ion channels. However, the pathogenesis of MAT needs to be explored. This review is aimed to summarize and analyze the pathogenesis in pediatric MAT.

Fetal Cardiac Function: Myocardial Performance Index

The Myocardial Performance Index (MPI) or Tei index, presented by Tei in 1995, is the ratio of the sum of the duration of the isovolumetric contraction time (ICT) and isovolumetric relaxation time (IRT) to the duration of the ejection time (ET). The Modified Myocardial Performance Index (Mod-MPI), proposed in 2005, is considered a reliable and useful tool in the study of fetal heart function in several conditions, such as growth restriction, twin-twin transfusion syndrome, maternal diabetes, preeclampsia, intrahepatic cholestasis of pregnancy, and adverse perinatal outcomes. Nevertheless, clinical translation is currently limited by poorly standardised methodology as variations in the technique, machine settings, caliper placement, and specific training required can result in significantly different MPI values. This review aims to provide a survey of the relevant literature on MPI, present a strict methodology and technical considerations, and propose future research.

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.

Fetal epicardial fat thickness in fetal growth restriction; effects on fetal heart function and relationship with the severity of disease

OBJECTIVE

To investigate fetal epicardial fat thickness (EFT) value in fetal growth restriction (FGR) and its relationship with clinical parameters, fetal modified myocardial index (Mod-MPI), and the Doppler parameters.

MATERIAL METHODS

Eighty-five pregnant women, with 30 diagnosed with FGR and 55 healthy pregnant women as control group participated in this prospective case-control study. FGR group was divided into 2 subgroups as early (n = 9) and late FGR (n = 21) groups. Demographic data were taken from the medical records. Amnion fluid value, fetal biometric measurements, and Doppler parameters were obtained. Fetal EFT and fetal Mod-MPI were measured by using the echocardiographic methods. The correlation tests were performed to assess the association between EFT and clinical and ultrasonographic parameters. p < .05 was interpreted as statistically significant.

RESULTS

EFT value was found statistically lower in the early and late FGR groups than the control group (p = .003). Higher umbilical artery pulsatility index (PI) and lower cerebroplacental ratio (CPR) values were found in the early and late FGR (p < .001, p = .001). The optimal EFT cutoff level to predict FGR disease was measured as 1.25 with 63.3% specificity and 77.4% sensitivity. Lower ejection time (ET) and higher Mod-MPI and isovolumetric contraction time (ICT) values were found in the group FGR with absent UAEDF than in the group FGR with no absent UAEDF (p = .001, p < .000, p < .000, respectively). Correlation tests showed statistically negative and weak correlations among EFT, umbilical artery PI, and mean Ut A-PI (p = .019, p = .019). Positive correlations were found in regard to gestational age, EFW, and EFT (p = .002, p < .000).

CONCLUSION

Our study showed that the measurement of EFT may contribute to predicting the diagnosis of FGR. Moreover, lower EFT values can be related to the severity of FGR. Future randomized control studies are needed to understand the effects and pathways of fetal EFT on fetal cardiac function.

Influence of birth weight on fetal cardiac indices at 35-37 weeks' gestation

OBJECTIVE

Echocardiographic studies have reported that fetuses with low birth weight, compared to those with normal birth weight, have globular hearts and reduced cardiac function. Dichotomizing continuous variables, such as birth weight, may be helpful in describing pathology in small studies but can prevent us from identifying physiological responses in relation to change in size. The aim of this study was to explore associations between fetal cardiac morphology and function and birth weight, as a continuous variable, as well as uterine artery (UtA) pulsatility index (PI), as an indirect measure of placental perfusion, and the cerebroplacental ratio (CPR), as an indirect measure of fetal oxygenation.

METHODS

This was a prospective study of 1498 women with singleton pregnancy undergoing routine ultrasound examination at 35 + 0 to 36 + 6 weeks' gestation. Pregnancies complicated by pregestational or gestational diabetes mellitus, chronic hypertension, pregnancy-induced hypertension or pre-eclampsia were excluded from the analysis. Conventional and more advanced echocardiographic modalities, such as speckle tracking, were used to assess fetal cardiac function in the right and left ventricles. The morphology of the fetal heart was assessed by calculating the right and left sphericity indices. In addition, the PI of the UtA, umbilical artery (UA) and fetal middle cerebral artery (MCA) was determined and the CPR was calculated by dividing MCA-PI by UA-PI. Multiple linear regression models were used to assess determinants of fetal echocardiographic parameters.

RESULTS

The study population included 146 (9.7%) small-for-gestational-age (SGA) fetuses with birth weight < 10^th percentile and 68 (4.5%) with fetal growth restriction (FGR). In the SGA and FGR groups, compared to the non-SGA and non-FGR fetuses, respectively, there was a more globular right ventricle and reduced left and right ventricular systolic function, and, from the left ventricular diastolic functional indices, the E/A ratio was increased. There was a linear association of right ventricular sphericity index, indices of left and right ventricular systolic function and E/A ratio with birth-weight Z-score. There were no significant associations between cardiac morphological and functional indices and UtA-PI Z-score or CPR Z-score.

CONCLUSIONS

This screening study at 35-37 weeks' gestation has demonstrated that birth weight is a determinant of fetal cardiac morphology and function but UtA-PI and CPR, as indirect measures of placental perfusion and fetal oxygenation, are not. This suggests that the differences in fetal cardiac indices between small and appropriately grown fetuses may be part of a normal physiological response to change in fetal size rather than part of a pathological adaptation to abnormal placental perfusion and fetal oxygenation. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.

Ductus venosus Doppler waveform pattern in fetuses with early growth restriction

INTRODUCTION

We aimed to assess if maximum velocities of the ductus venosus flow velocity waveform are associated with adverse outcomes in early-onset fetal growth restriction.

MATERIAL AND METHODS

Retrospective cohort study from two tertiary referral units, including singleton fetuses with estimated birthweight or fetal abdominal circumference ≤10th centile and absent or reversed end-diastolic velocity in the umbilical artery delivered between 26⁺⁰ and 34⁺⁰  weeks of gestation. Pulsatility index for veins, and maximum velocities of S-, D-, v- and a-waves, were measured in the ductus venosus within 24 hours of birth. Logistic regression was used to describe the relation between severe neonatal morbidity or neonatal death and clinical independent predictors.

RESULTS

The study population included 132 early-onset fetal growth restriction fetuses. Newborns with neonatal morbidity or neonatal death had significantly lower values of v/D maximum velocity ratio multiples of the median (0.86 vs 095; P = 0.006) within 24 hours of birth. The v/D ratio remained a significant predictor of neonatal death or severe neonatal morbidity after adjusting for gestational age and birthweight (adjusted odds ratio 0.065, 95% confidence interval 0.004-0.957).

CONCLUSIONS

Assessment of ductus venosus v/D maximum velocity ratio might help to identify fetal growth restriction fetuses at increased risk for neonatal death or severe neonatal morbidity. Confirmation in prospective studies is necessary.

Utility of the modified myocardial performance index in growth-restricted fetuses

OBJECTIVES

The modified myocardial performance index (Mod-MPI) can be used to assess myocardial function. Fetal growth restriction can affect fetal myocardial function, thereby altering the Mod-MPI. The results of previous studies on the utility of the Mod-MPI in growth-restricted fetuses are conflicting. The aim of this study was to calculate the left modified-MPI in growth-restricted fetuses and to compare the results with those of healthy fetuses.

METHODS

This was a prospective cross-sectional case-control study. In total, 40 women with growth-restricted fetuses and 40 women with fetuses of normal weight (controls) at 29-39 gestational weeks were enrolled in the study. An experienced obstetrician calculated the Mod-MPI for each fetus. Women with systemic diseases or fetuses with chromosomal/structural abnormalities were excluded from the study. The results of Mod-MPI measurements of the two groups were compared.

RESULTS

The mean single deepest vertical pocket (SDVP) of amniotic fluid, estimated fetal weight (EFW), and isovolumetric relaxation time (IRT) was significantly lower in the fetal growth restriction (FGR) group as compared with these parameters in the control group (P < .05). The uterine artery (UtA) pulsatility index (PI) was significantly higher in the FGR group as compared with that in the control group (P < .05). There were six cases of absent end-diastolic flow (AED) in the FGR group. There were no statistically significant between-group differences in the Mod-MPI, isovolumetric contraction time (ICT), and ejection time (ET) (P > .05). There was also no statistically significant correlation between the Mod-MPI in the fetuses with AED and the control group for Mod-MPI (P > .05).

CONCLUSION

The utility of the Mod-MPI in FGR remains unclear. Future studies with larger populations are needed to determine the utility of the Mod-MPI as a predictor of cardiac compromise in FGR.

Correlation between fetoplacental Doppler indices and measurements of cardiac function in term fetuses

OBJECTIVE

Redistribution of cardiac output (CO) is responsible for the brain-sparing effect seen during periods of fetal stress. Our aim was to investigate prospectively the correlation between fetoplacental Doppler indices and measurements of cardiac function in uncomplicated term singleton pregnancy.

METHODS

This was a prospective observational study of normotensive women with appropriately grown, non-anomalous singleton pregnancy. Participants underwent fortnightly ultrasound examinations from 36 weeks' gestation until delivery, and intrapartum and neonatal outcomes were recorded. The correlation between fetoplacental Doppler indices and various measurements of cardiac function was evaluated.

RESULTS

The study cohort comprised 273 singleton pregnancies. The cerebroplacental ratio (CPR) was correlated positively with left ventricular CO (LVCO) (P < 0.001, rho = 0.29), left-to-right ventricular CO ratio (LVCO/RVCO; P < 0.001, rho = 0.41), global left ventricular strain (P < 0.01, rho = 0.17) and global right ventricular strain (P < 0.001, rho = 0.22). The CPR was correlated inversely with the left ventricular myocardial performance index (P < 0.01, rho = -0.18) and the RVCO (P < 0.001, rho = -0.28). The LVCO and global left ventricular strain were correlated positively with umbilical venous flow (P = 0.04, rho = 0.18 and P < 0.001, rho = 0.25, respectively). There was minimal or no correlation between either the mean uterine artery pulsatility index (PI) or umbilical artery PI with any cardiac indices.

CONCLUSION

The fetal CPR, middle cerebral artery PI and umbilical venous flow are correlated positively with LVCO, LVCO/RVCO and global left ventricular strain in low-risk term pregnancies. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Assessment of fetal left ventricular modified myocardial performance index and its prognostic significance for adverse perinatal outcome in intrahepatic cholestasis of pregnancy

Objective: To investigate the association between fetal left ventricular modified myocardial performance index (LMPI) and intrahepatic cholestasis of pregnancy (ICP) and to evaluate the value of LMPI in predicting adverse perinatal outcomes in ICP.Study design: In a cross-sectional case-control study, 40 women with ICP were compared with 40 gestational age-matched healthy controls. The isovolumetric contraction time (ICT), isovolumetric relaxation time (IRT), and ejection time (ET) were measured using the Doppler signals of the opening and closing of the mitral and aortic valves. LMPI was calculated as (ICT + IRT)/ET. An adverse perinatal outcome was defined with at least one of the following: non-reassuring fetal heart rate tracing, umbilical cord pH <7.20, the presence of meconium in amnion, and neonatal intensive care unit (NICU) admission.Results: Mean gestational age at delivery and mean birth weight were significantly lower and the incidences of cesarean section rate, non-reassuring fetal heart rate tracing, the presence of meconium in amnion, and NICU admission were significantly higher in the ICP group (p < .01). Mean LMPI, ICT, and IRT values were significantly higher in the ICP group (p < .01). The area under the receiver operating characteristic (ROC) curve for LMPI in prediction of adverse perinatal outcome was 0.740 (95% CI: 0.607-0.873, p = .001) and a cut-off LMPI of 0.41 conferred a sensitivity of 85% and a specificity of 61%.Conclusions: There is an impaired global ventricular function in ICP fetuses demonstrated by increased LMPI. High LMPI is associated with adverse perinatal outcome in ICP.

Modified myocardial performance index and its prognostic significance for adverse perinatal outcome in early and late onset fetal growth restriction

Objective: To compare the fetal modified myocardial performance index (Mod-MPI) in appropriately grown, early (EO) and late onset (LO) fetal growth restricted (FGR) fetuses and to assess its prognostic significance for adverse perinatal outcome.Study design: In a prospective case-control study, Mod-MPI was performed in 22 and 51 fetuses with EO and LO-FGR fetuses, respectively. Mod-MPI values of FGR fetuses were compared against gestation-matched controls (34 for EO-, and 32 for LO-FGR, respectively). Correlation testing related with poor perinatal outcomes were performed.Results: Incidences of pathologic uterine artery Doppler rate, cesarean section rate, 5-min Apgar score < 7, neonatal intensive care unit (NICU) admission and perinatal mortality were significantly higher in the EO-FGR group (p < .001). There was a decrease in Mod-MPI with gestational age in the normal (Pearson's r = 0.401, p < .001), and growth-restricted fetuses (Pearson's r = 0.248, p = .034). Mean Mod-MPI values were significantly higher in both EO- and LO-FGR group than gestation-matched controls (p < .001). There was no significant correlation between Mod-MPI values and perinatal deaths (Pearson's r = 0.004, p = .987) and 5-min Apgar score < 7 (Pearson's r = 0.391, p = .088) in the EO-FGR fetuses. There was a significant negative correlation between Mod-MPI values and cerebroplacental ratio (CPR) values (Pearson's r = -0.288, p = .041); however no significant correlation between Mod-MPI values and 5-min Apgar score< 7, and fetal distress during labor (Pearson's r = 0.149, p = 0.297) in the LO-FGR fetuses was noted.Conclusion: EO and LO-FGR fetuses have significantly higher Mod-MPI values, demonstrating prenatal cardiac dysfunction. Evaluating Mod-MPI is not so effective in predicting poor perinatal outcome in both EO and LO-FGR fetuses.

Fetal cerebral and cardiac hemodynamics in postdate pregnancy

Objective: We aimed to determine the fetal cerebro-placental Doppler indices and modified myocardial performance index (Mod-myocardial performance index (MPI)) in this homogenous group of postdated pregnancies. Methods: A total of 92 singleton pregnant women were included in this prospective study. The study involved three groups; full term control (Group 1, n = 42, 39 0/7 to 40 6/7 week' gestation), late term (Group 2, n = 34, 41 0/7 to 41 6/7 week' gestation) and post term (Group 3, n = 16, ≥ 42 0/7 weeks' gestation). Each participant underwent a Doppler assessment of the fetal umbilical artery (UA), middle cerebral artery (MCA), Mod-MPI. We determined the correlation of the Doppler indices and mod-MPI in patients with unfavorable outcome. Results: MCA pulcatility indices (PI), cerebroplacental ratio (CPR) values were significantly higher in the control group than those in the late-term and post-term groups (Group 1: 1.63 ± 0.3, Group 2: 1.27 ± 0.51, Group 3: 1.13 ± 0.22, respectively, p < .001). The Mod-MPI was significantly higher in the late-term and post-term groups than in the control group (Group 1:0.38 ± 0.1, Group 2: 0.59 ± 0.09, Group 3: 0.60 ± 0.08, respectively, p < .001. MCA PI and CPR were only significantly lower in patients with unfavorable outcome). The threshold value for CPR levels for predicting unfavorable outcome in postdate pregnancies was calculated as 1.11 (area under curve [AUC] 0.762, confidence interval [CI] 0.575-0.95) with 72.7% sensitivity and 71.8% specificity. Conclusions: Fetal Mod-MPI does not differ in postdate pregnancies with favorable and unfavorable outcome. The monitorization of fetal well-being with CPR may help to clinicians to select patient for expectant management in postdate pregnancies.

Fetal myocardial performance index in assessment and management of small-for-gestational-age fetus: a cohort and nested case-control study

OBJECTIVE

To assess the clinical utility of the fetal myocardial performance index (MPI) in assessment and management of the small-for-gestational-age (SGA) fetus/growth-restricted fetus (FGR).

METHODS

This was a prospective cohort study in metropolitan Australia of patients referred in the period June 2012 to March 2015 to fetal medicine services at 24-38 weeks' gestation for suspected singleton SGA/FGR (estimated fetal weight (EFW) < 10^th centile with or without abnormal umbilical artery (UA) Doppler) pregnancy. Patients had MPI assessed in addition to routine measures, and were followed through to birth. We compared MPI values against those of a local reference population and gestational age-matched controls, and assessed the correlation with perinatal outcome and other Doppler measures.

RESULTS

Fifty-two cases were included, 38 diagnosed < 32 weeks and 14 diagnosed ≥ 32 weeks. None demonstrated significantly elevated left, right or delta MPI compared with the reference population or with gestational age-matched controls at the time of first MPI evaluation. There were no consistent longitudinal patterns in MPI that would suggest its clinical utility. The mean ± SD gestational age at delivery was 34.6 ± 3.8 weeks and birth weight was 1.7 ± 0.6 kg, and the median neonatal hospital admission time was 27 days, confirming a pathological cohort. There were no significant correlations between left, right or delta-MPI and perinatal outcome, although there were significant correlations between UA, middle cerebral artery (MCA) and ductus venosus (DV) Doppler and perinatal outcome (birth weight, gestational age at birth and length of neonatal hospital stay). Exploratory subgroup comparisons (EFW < 3^rd vs 3^rd -10^th centile; early- vs late-onset; abnormal vs normal UA Doppler) found only minor differences in MPI, reaching statistical, but not clinical, significance, only in the EFW < 3^rd vs 3^rd -10^th centile comparison.

CONCLUSIONS

MPI did not demonstrate clinical utility in either triage or longitudinal follow-up of an SGA/FGR cohort presenting to fetal medicine services. Given that prior research suggesting its utility originates from single-center cohorts, while multicenter, large cohorts have suggested little utility or no additional utility if routine UA/MCA/DV Doppler is performed, publication bias may have affected previous reports. It seems unlikely that MPI has clinical utility in assessment and management of SGA/FGR fetuses. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Assessment of Fetal Myocardial Performance Index in Women with Placenta Previa

Background

This study investigated whether fetuses of placenta previa pregnancies have cardiac dysfunction by use of a modified myocardial performance index (Mod-MPI).

Material/Methods

A prospective cross-sectional study was conducted including 178 fetuses at 28–40 weeks of gestation. Eighty-nine fetuses of mothers with placenta previa and without pregnancy complications were recruited (placenta previa group) and matched with 89 fetuses of mothers with normal pregnancies (control group). Fetal cardiac function parameters and perinatal outcomes as well as the Mod-MPI were compared between the 2 groups.

Results

The median Mod-MPI was significantly increased in fetuses of mothers with placenta previa compared with controls (0.47±0.05 vs. 0.45±0.05; P<0.01). Among fetuses of mothers with or without placenta previa, the Mod-MPI was significantly higher in the incomplete placenta previa group compared with the complete placenta previa group and control group (P<0.01). An increased Mod-MPI in placenta previa pregnancies was independently associated with fetal cord pH <7.2 (odds ratio, 4.8; 95% confidence interval, 0.98–23.54; P=0.003).

Conclusions

There is impairment of fetal cardiac function in pregnancies with placenta previa. An increased MPI was independently associated with adverse perinatal outcomes to some extent in the placenta previa pregnancies.

Prospective longitudinal assessment of the fetal left modified Myocardial Performance Index

INTRODUCTION

The fetal left modified Myocardial Performance Index (Mod-myocardial performance index (MPI)) is a measure of systolic versus diastolic time intervals obtained from a single cardiac cycle with ultrasound. It is a measure of global ventricular function and has been investigated for potential utility in fetal conditions associated with cardiac dysfunction.

OBJECTIVES

The objective of this study is to compare values from a precisely replicated fetal left Mod-MPI technique to published reference ranges.

METHODS

Three hundred and sixty-five nulliparae prospectively underwent fetal left Mod-MPI measurement at 27⁺⁰-29⁺⁰ and 35⁺⁰-37⁺⁰ weeks' gestation. Measurements from pregnancies complicated by gestational diabetes mellitus, preeclampsia, or a small-for-gestational-age (<10th centile) infant were excluded. Mod-MPI values were compared with three published references created using similar measurement techniques.

RESULTS

Compared with one selected reference, at 29⁺⁰ and 35⁺⁰-37⁺⁰ weeks' gestation, 90-100% of our values fell within the 5th-95th percentile range as expected. Thus, this reference range was validated for our population in late pregnancy. However, the expected level of concordance was not seen at 27⁺⁰-28⁺⁶ weeks'. The other two references to which we compared our Mod-MPI values demonstrated poor concordance, especially at 27⁺⁰-29⁺⁰ weeks'. Pearson interobserver correlation was also improved at 35⁺⁰-37⁺⁰ weeks' at 0.434, compared with 0.083 at 27⁺⁰-29⁺⁰ weeks' gestation.

CONCLUSIONS

Concordance and interobserver variability between our cohort and similar populations were both improved at 35⁺⁰-37⁺⁰ weeks' compared with 27⁺⁰-29⁺⁰ weeks' gestation. Overall, variable Mod-MPI reproducibility across gestations limits clinical application, especially earlier in pregnancy. Manual Mod-MPI measurement should be considered most reliable in late pregnancy until automated MPI measurement is possible.

Determination of the fetal myocardial performance index in women with gestational impaired glucose tolerance and to assess whether this parameter is a possible prognostic indicator of adverse fetal outcome

AIM

The aim of this study was to investigate if the myocardial performance index (MPI) is altered in fetuses in women with gestational impaired glucose tolerance (GIGT), controlled on diet and whether this parameter is also predictive of adverse outcome in this group, as in poorly controlled gestational diabetes.

METHODS

In a prospective cross-sectional study, 32 women with GIGT on diet in the 3rd trimester were recruited and matched with 32 women with normal pregnancies (control group). Using Doppler echocardiography, the MPI was calculated. Placental resistance Doppler markers in both groups were also determined. An abnormal outcome was defined as any of the following: stillbirth, neonatal death, neonatal intensive care unit (NICU) admissions, tachypnea with pulmonary oedema, neonatal cord pH <7.15, five minute Apgar score <7, and cardiomyopathy.

RESULTS

The cases had a significantly higher median MPI compared to controls, p value <.0001. There were eight abnormal outcomes recorded in the 32 fetuses in the study group, corresponding to an adverse outcome rate of 25%. Fetuses with an adverse outcome had significantly higher MPI measurements compared to the GIGT fetuses with normal outcome. The MPI served as an excellent predictor of adverse outcome in the GIGT fetuses, with a total area under the ROC curve of 0.96. An MPI z-score greater than 4.0 conferred a sensitivity of 100% and specificity of 80%. No abnormal outcomes were noted in the control group.

CONCLUSIONS

The MPI is impaired in fetuses in GIGT women, with fetuses with an adverse outcome having significantly higher MPI measurements compared to the fetuses with normal outcome in the GIGT group. MPI has the potential to improve fetal surveillance in gestational diabetes.

Assessment of fetal myocardial performance in severe early onset pre-eclampsia (EO-PET) with and without intrauterine growth restriction across deteriorating stages of placental vascular resistance and links to adverse outcomes

OBJECTIVE

To determine whether fetuses in severe early onset pre-eclampsia (EO-PET) with or without intrauterine growth restriction has cardiac dysfunction across deteriorating stages of placental vascular resistance and whether this dysfunction influences perinatal outcome.

STUDY DESIGN

This was a prospective cross-sectional study performed in a tertiary care university medical centre. Sixty pregnant patients with severe early-onset pre-eclampsia between 27 and 32 weeks were recruited and matched with 60 patients having normal pregnancies. An analysis of cardiac function using the myocardial performance index (MPI) and early ventricular filling (E) and late active atrial contraction (A) ratios (E/A ratios) in the study group was performed compared to controls and further analysis was performed based on worsening placental vascular resistance and presence of growth restriction.

RESULTS

MPI values were increased in the pre-eclamptic group, irrespective if growth restriction co-exists, compared to controls (0.61 vs 0.38, p<0.001). Its median value progressively increased with worsening placental vascular resistance. For adverse perinatal outcome cut-off MPI values have been suggested. The E/A ratios were significantly decreased in the pre-eclamptic group compared to controls (0.66 vs 0.79, p<0.0001). No adverse outcomes were noted in the control group.

CONCLUSION

Fetal cardiac function is significantly impaired in pregnancies complicated by severe early onset pre-eclampsia, irrespective if growth restriction co-exists and worsens with deteriorating grades of placental vascular resistance. The MPI can potentially be integrated into routine fetal surveillance techniques.

Can the Myocardial Performance Index Be Used as a New Predictive Factor for a Poor Prognosis in Fetuses With Idiopathic Polyhydramnios?

OBJECTIVES

The purpose of this study was to determine whether there are any changes in cardiac function in fetuses with idiopathic polyhydramnios and also to evaluate the value of the myocardial performance index for prediction of adverse perinatal outcomes.

METHODS

A prospective case-control study was conducted with a total of 134 fetuses between 24 and 40 weeks' gestation. Polyhydramnios was defined as an amniotic fluid index of greater than 24 cm. Seventy-three fetuses of healthy mothers were assigned as the control group whereas 36 fetuses with an amniotic fluid index of 24 to 34 cm constituted the nonsevere polyhydramnios group, and 31 fetuses with an amniotic fluid index of 35 cm or greater constituted the severe polyhydramnios group. Fetal echocardiography was performed to compare cardiac function parameters among groups. To determine which perinatal outcomes were independently associated with an increased myocardial performance index, a multivariate logistic regression analysis was performed.

RESULTS

The myocardial performance index was significantly higher in polyhydramnios groups compared with controls (P < .001). Among fetuses with polyhydramnios, the myocardial performance index was significantly higher in severe polyhydramnios compared with nonsevere polyhydramnios (P = .003). An increased myocardial performance index in polyhydramnios was independently associated with nonreassuring fetal status (odds ratio, 2.12; 95% confidence interval, 1.41-4.53; P = .005), emergency cesarean delivery (odds ratio, 1.54; 95% confidence interval, 1.12-2.37; P= .025), and respiratory distress syndrome (odds ratio, 1.79; 95% confidence interval, 1.21-3.87; P = .012).

CONCLUSIONS

An increased myocardial performance index is an early indicator of adverse perinatal outcomes in pregnancies complicated by idiopathic polyhydramnios.

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.

Fetal left modified myocardial performance index measured by the Auto Mod-MPI system: development of reference values and application to recipients of twin-to-twin transfusion syndrome

OBJECTIVES

To establish normal reference ranges for the fetal left modified myocardial performance index (Mod-MPI) measured by the Auto Mod-MPI system and evaluate Mod-MPI changes in recipients of twin-to-twin transfusion syndrome (TTTS) before and after fetoscopic laser coagulation.

METHODS

This was a prospective longitudinal study of normal singleton fetuses from 12.0 to 40.0 weeks of gestation. TTTS cases treated by laser coagulation were reviewed for Mod-MPI measurements of recipients. All measurements were performed using the Auto Mod-MPI system by a single experienced operator.

RESULTS

Among a total 447 examinations from 222 fetuses, we were unable to measure the Mod-MPI in two cases, and therefore, 445 examinations were analyzed. The median Mod-MPI consistently increased from 0.44 to 0.56 throughout gestation. The median isovolumetric contraction time (ICT) and isovolumetric relaxation time (IRT) also increased with advancing gestational age. The ejection time (ET) increased until 27 weeks of gestation and decreased thereafter. In the 30 recipients, Mod-MPI, ICT, and IRT increased before laser coagulation and significantly decreased after laser coagulation.

CONCLUSION

Normal reference values for left Mod-MPI were established using the Auto Mod-MPI system, and these might be useful for assessing cardiac function in TTTS. © 2016 John Wiley & Sons, Ltd.