Assessment of fetal modified myocardial performance index in early-onset and late-onset fetal growth restriction

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.

Association between Doppler assessment and secondary cesarean delivery for intrapartum fetal compromise in small-for-gestational-age fetuses

PURPOSE

To elucidate the association between arterial and venous Doppler ultrasound parameters and the risk of secondary cesarean delivery for intrapartum fetal compromise (IFC) and neonatal acidosis in small-for-gestational-age (SGA) fetuses.

METHODS

This single-center, prospective, blinded, cohort study included singleton pregnancies with an estimated fetal weight (EFW) < 10th centile above 36 gestational weeks. Upon study inclusion, all women underwent Doppler ultrasound, including umbilical artery (UA) pulsatility index (PI), middle cerebral artery (MCA) PI, fetal aortic isthmus (AoI) PI, umbilical vein blood flow (UVBF), and modified myocardial performance index (mod-MPI). Primary outcome was defined as secondary cesarean section due to IFC.

RESULTS

In total, 87 SGA pregnancies were included, 16% of which required a cesarean section for IFC. Those fetuses revealed lower UVBF corrected for abdominal circumference (AC) (5.2 (4.5-6.3) vs 7.2 (5.5-8.3), p = 0.001). There was no difference when comparing AoI PI, UA PI, ACM PI, or mod-MPI. No association was found for neonatal acidosis. After multivariate logistic regression, UVBF/AC remained independently associated with cesarean section due to IFC (aOR 0.61 [0.37; 0.91], p = 0.03) and yielded an area under the curve (AUC) of 0.78 (95% CI, 0.67-0.89). A cut-off value set at the 50th centile of UVBF/AC reached a sensitivity of 86% and specificity of 58% for the occurrence of cesarean section due to IFC (OR 8.1; 95% CI, 1.7-37.8, p = 0.003).

CONCLUSION

Low levels of umbilical vein blood flow (UVBF/AC) were associated with an increased risk among SGA fetuses to be delivered by cesarean section for IFC.

Reference Ranges for Left Modified Myocardial Performance Index: Systematic Review and Meta-Analysis

INTRODUCTION

The modified myocardial performance index (mod-MPI) is a noninvasive Doppler-derived metric used to evaluate fetal cardiac function. However, the reference ranges for mod-MPI in normal fetuses are not clearly defined, which limits the use of this technology in fetuses with potential cardiac compromise. Thus, we aimed to perform a systematic review and meta-analysis of published mod-MPI reference ranges across gestation.

METHODS

The published literature was systematically searched, and all published articles in any language that provided values for the left ventricular mod-MPI obtained in low-risk, singleton fetuses were considered eligible for further review. All retrieved titles and abstracts were independently reviewed by two researchers. Mean and standard deviation by gestational week was extracted or calculated from published data. DerSimonian-Laird random-effects models were used to estimate pooled means and 95% confidence intervals (CIs).

RESULTS

The search resulted in 618 unique citations, of which 583 did not meet inclusion criteria, leaving 35 abstracts selected for full-text review. Review of the references of these 35 articles identified another 5 studies of interest. Of the 40 articles reviewed, six met inclusion criteria. There was significant heterogeneity seen in the mod-MPI results reported. Mod-MPI increased as pregnancy progressed in all studies. The pooled mean mod-MPI at 11 weeks' gestation was 0.400 (95% CI 0.374-0.426) and increased to 0.585 (95% CI 0.533-0.637) at 41 weeks' gestation. The increase was linear in 5 of 6 studies, while in 1 study, the mod-MPI was stable until 27 weeks' gestation, and then increased throughout the third trimester. Despite all having trends increasing over pregnancy, there was no study in which all the weekly means fell within the pooled 95% CI.

CONCLUSION

While mod-MPI does increase over gestation, the true "reference ranges" for fetuses remain elusive. Future efforts to further optimize calculation of time intervals possibly via automation are desperately needed to allow for reproducibility of this potentially very useful tool to assess fetal cardiac function.

Modified Myocardial Performance Index in Fetal Growth Disturbances as Diagnostic and Prognostic Adjunct

BACKGROUND

Fetal growth disturbance can be associated with cardiac dysfunction. This study aimed to assess the modified myocardial performance index in growth-restricted and appropriate for gestational age fetuses and evaluate both its prognostic value in perinatal period and also its association with adverse perinatal outcomes.

METHODS

Totally 131 pregnant women were included in this prospective study. Of these, 56 cases were in study group with a diagnosis of small fetus and 75 cases were in control group with a diagnosis appropriately grown fetus. Fetal echocardiography was performed in all pregnant women to measure modified myocardial performance index. Umbilical, middle cerebral and uterine artery Doppler ultrasound parameters were measured in the study group. Small fetuses were categorized into 2 subgroups of late-onset fetal growth restriction and small for gestational age.

RESULTS

Modified myocardial performance index was significantly higher in small fetuses compared to controls (0.45 vs. 0.37, P <.001). Newborn intensive care unit admission rates were significantly higher in small fetuses than in controls (chi-square test, P <.001). The highest mean modified myocardial performance index was recorded in the late-onset fetal growth restriction subgroup (0.45 vs. 0.41 vs. 0.37). The sensitivity and specificity of modified myocardial performance index in predicting adverse outcomes at a cut-off value of 0.41 were 63% and 75%, respectively. There was a significant negative correlation between modified myocardial performance index values and birth weights.

CONCLUSIONS

We found higher left fetal heart modified myocardial performance index values in small fetuses indicating the presence of prenatal cardiac dysfunction. Fetal myocardial performance deteriorates in concordance with severity of growth restriction. Modified myocardial performance index can also be used to predict adverse perinatal outcomes among growth-restricted fetuses.

Role of myocardial performance index (MPI) and cerebro-placental ratio (CPR) in predicting adverse perinatal outcome

INTRODUCTION

This study aimed to evaluate the association of the Myocardial Performance Index (MPI) and Cerebro-Placental Ratio (CPR) in predicting adverse perinatal outcomes in fetuses who are appropriately-grown (AGA), small-for-gestational-age (SGA) and growth restricted (FGR).

METHODS

Singleton pregnancies were recruited after 24 weeks. The patients were recruited after having been classified as AGA (AC/EFW > 10th centile), SGA (AC/EFW-3rd-10th centile without doppler abnormalities), and FGR (AC/EFW < 3rd centile or 3rd-10th centile with doppler abnormalities). A total of 103 cases comprising 48 AGA, 11 SGA, and 44 FGRfetuses were recruited. The Pulsatility Index of the Umbilical artery, Middle cerebral artery, Ductus Venosus, and Aortic Isthmus was obtained. MPI and CPR were calculated too. The primary outcome was to evaluate the predictive value of MPI and CPR for the composite adverse perinatal outcome.

RESULTS

The mean gestational age of recruitment was 30 weeks. The OR for Composite Adverse Perinatal Outcome in FGR group for MPI > .47 and CPR < 1.67 was 3.48 (95% CI: 1.00-12.24, p-value < .05) with sensitivity and specificity of 65% each and 11.08 (95% CI: 2.62-46.83, p-value = .001) with the sensitivity of 82% and specificity of 70%, respectively. When combined together, MPI and CPR yielded an OR of 58.5 (95% CI: 4.58-746.57, p-value = .002) with a sensitivity of 56.5% and specificity of 95% in the FGR group.

CONCLUSIONS

MPI in conjunction with CPR can be used together to predict adverse perinatal outcomes in FGR.

Assessment of left ventricular function by spatio-temporal image correlation in fetuses with fetal growth restriction

AIM

To compare the evaluation of left ventricular function by spatio-temporal image correlation (STIC) between fetal growth restriction (FGR) fetuses and normal fetuses.

METHODS

Forty-two FGR fetuses and 50 normal fetuses with gestational age ranging from 28 to 35 weeks, were chosen for the study group and control group, respectively. The fetal heart was acquired using the STIC modality, beginning with a four-chamber view. A 7.5-12.5 s acquisition time and 20-35°angle of the acquisition were used for the acquisition. The resulting STIC dataset was saved for offline analysis. Ventricular volumes were measured using the Virtual Organ Computer-aided Analysis (VOCAL) mode, where the observer defines the contours of the ventricle and traces the endocardia. Stroke volume (SV) = end diastolic volume (EDV)-end systolic volume (ESV) and ejection fraction (EF) = SV/EDV × 100%. The data of the two groups were analyzed.

RESULTS

(1) SV increased with fetal growth in both groups and was positively correlated with gestational age (p < .01), whereas EF remained constant throughout gestation and had no correlation with gestational age (p > .05). (2) There was no difference found in EF between the two groups, (p > .05), SV was significantly lower in FGR group than those in the normal group (p < .01).

CONCLUSION

The STIC is a precise method for calculating fetal ventricular volume changes and functions. Reduced SV occurred at the initial stage of fetal deterioration before the discovery of abnormal EF in FGR fetuses, indicating cardiac dysfunction. SV could be a sensitive indicator of cardiac dysfunction. The use of EF to assess fetal cardiac function is not perfect.

Prenatal Prediction of Fetal Growth Restriction and Postnatal Outcomes by Ultrasound Assessment of Fetal Myocardial Performance Index and Blood Flow Spectrum

Objective

Fetal growth restriction (FGR) affects 5% to 10% of newborns and is a major determinant of perinatal morbidity and mortality. Myocardial performance index (MPI), also known as the Tei index, is a useful, noninvasive, and Doppler-derived myocardial performance tool for fetal cardiac function evaluation. The purpose of the study is to evaluate ultrasonic prediction on FGR and postnatal outcomes using MPI and blood flow spectrum.

Methods

This retrospective study included 240 pregnant women developing FGR and 240 healthy pregnant women. The blood flow spectrum of middle cerebral artery (MCA), umbilical artery (UA), and ductus venous including systolic to diastolic ratio (S/D), resistant index (RI), pulse index (PI), and peak ventricular systolic velocity/atrial contraction valley velocity (S/a) were examined using the GE Voluson E8 ultrasound system.

Results

The MPI, S/D, RI, PI of UA, and S/a were all higher but S/D, RI, and PI of MCA were lower in the FGR group than those in the control group (P < 0.001). The MPI, S/D, RI, PI of UA, S/D, RI, PI of MCA, and ductus venous S/a yielded AUC of 0.813, 0.835, 0.791, 0.804, 0.789, 0.796, 0.803, and 0.784 when they were used to predict the incidence of FGR. Of note, the pregnant women with poor pregnancy outcomes exhibited higher values of MPI, S/D, RI, PI of UA, and S/a with lower scores of 1 min Apgar concomitant with lower values regarding S/D, RI, and PI of MCA than those with favorable pregnancy outcomes (P < 0.001). The MPI (r = -0.623), S/D (r = -0.660), RI (r = -0.601), PI (r = -630) of UA, and S/a (r = -0.573) shared negative correlations with 1 min Apgar scores (P < 0.001). Of note, the S/D (r = 0.562), RI (r = 0.597), and PI (r = 0.619) of MCA were positively correlated with 1 min Apgar scores (P < 0.001). It was revealed that the MPI, S/D, RI, PI of UA, S/D, RI, PI of MCA, and ductus venous S/a yielded AUC of 0.806, 0.833, 0.774, 0.788, 0.807, 0.729, 0.748, and 0.770 when they were used to predict the incidence of poor pregnancy outcomes for pregnant women developing FGR.

Conclusion

Our study demonstrates good ultrasonic prediction on FGR and postnatal outcomes using MPI and blood flow spectrum.

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.

Fetal cardiac alterations in the late-onset growth-restricted fetuses: A prospective case-control study

AIM

Fetal growth restriction (FGR) has significant consequences on cardiac functions. This study aims to evaluate cardiac functional parameters in late-onset (FGR) fetuses and compare those appropriate for gestational age (AGA) fetuses.

MATERIAL AND METHODS

Fifty-six singleton pregnancies were involved in this prospective case-control study. Delphi consensus was used to define late-onset FGR. We compared the E/A ratio, left myocardial performance index (MPI) and tricuspid annular plane systolic excursion (TAPSE) in late-onset FGR cases and gestational age-matched AGA fetuses.

RESULTS

Twenty-eight late-onset FGR and 28 AGA fetuses were enrolled. The mean gestational age in the late-onset FGR group was 34.1 ± 2.3 weeks and 34.4 ± 2.1 in controls. The E/A ratio was 0.88 ± 0.09 in AGA fetuses, 0.79 ± 0.11 in the late-onset FGR group, and significantly lower in late-onset FGR fetuses (p: 0.012). Left MPI was 0.51 ± 0.09 in AGA and 0.62 ± 0.11 in the late-onset FGR group. Left MPI was markedly higher in late-onset FGR fetuses (p: 0.024). TAPSE was 7.4 ± 2.9 mm in controls and 5.2 ± 1.8 in the late-onset FGR group, and it was significantly shorter in the late-onset FGR fetuses (p: 0.016).

CONCLUSION

Late-onset FGR is associated with cardiac remodeling and dysfunction. Fetal echocardiography may be beneficial to detect those subtle cardiac changes.

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.

Obstetric ultrasound: where are we and where are we going?

Diagnostic ultrasound (DUS) is, arguably, the most common technique used in obstetrical practice. From A mode, first described by Ian Donald for gynecology in the late 1950s, to B mode in the 1970s, real-time and gray-scale in the early 1980s, Doppler a little later, sophisticated color Doppler in the 1990s and three dimensional/four-dimensional ultrasound in the 2000s, DUS has not ceased to be closely associated with the practice of obstetrics. The latest innovation is the use of artificial intelligence which will, undoubtedly, take an increasing role in all aspects of our lives, including medicine and, specifically, obstetric ultrasound. In addition, in the future, new visualization methods may be developed, training methods expanded, and workflow and ergonomics improved.

Normal reference ranges for fetal cardiac function: Assessed by modified Doppler myocardial performance index (Mod MPI) in the Egyptian population

AIM

To develop gestational age-based reference ranges for the modified Doppler myocardial performance index (Mod MPI) and to examine the maternal characteristics that affect this measurement.

METHODS

This was a cross-sectional study, comprised of 1021 healthy pregnancies between 20+0 to 35+6 weeks' gestation. They were all undergoing ultrasound examination in Cairo Fetal Medicine Unit (CAIFM) in Cairo University, Egypt from 1st April 2017 till 1st April 2019. Mod MPI was obtained used method described by Friedman et al. (2003). Median and SD models were fitted between Mod MPI and gestational age. The distributions of Mod MPI Z-scores were examined in relation to maternal characteristics RESULTS: The normal Mod MPI in second and third trimester (20 + 1 to 35 + 6 weeks' gestation) was 0.408 ± 0.08. Mod MPI was not affected by maternal age, body mass index (BMI) or parity (p value 0.5, 0.6 and 0.2 respectively).

CONCLUSION

This study established normal reference ranges for Mod MPI according to gestational age and generated a graph with 5th,10th, 90th and 95th centiles. Maternal characteristics as age, BMI or parity do not affect value of Mod MPI.

Assessment of fetal modified myocardial performance index in early-onset and late-onset fetal growth restriction

Aim

To investigate the changes of modified myocardial performance index (Mod‐MPI) in early‐onset and late‐onset fetal growth restriction (FGR) cases, and its association with adverse perinatal outcome.

Methods

This was a prospective study on 77 early‐onset and 100 late‐onset FGR cases. Hundred normal fetuses were matched as control groups for early‐onset and late‐onset FGR groups, respectively. Mod‐MPI and vessel Doppler parameters including umbilical artery (UA), ductus venosus (DV), and middle cerebral artery (MCA) were measured. Perinatal outcomes were followed up. Mod‐MPI of FGR cases were compared in normal Doppler, abnormal Doppler, and control groups. The association of Mod‐MPI and perinatal outcome was investigated, and further efficacy of Mod‐MPI predicting adverse outcome was studied.

Results

Compared with control groups, both abnormal and normal Doppler groups showed increased Mod‐MPI in early‐onset and late‐onset FGR, respectively. Mod‐MPI had no significant difference between abnormal and normal Doppler groups. Mod‐MPI was associated with adverse outcome in early‐onset FGR (OR = 3.307) and late‐onset FGR (OR = 3.412). The sensitivity and specificity of Mod‐MPI predicting adverse outcome were 60% and 80% when cutoff value was 0.47 in early‐onset FGR. And they were 65% and 70% when cutoff value was 0.50 in late‐onset FGR.

Conclusion

Fetal growth restriction fetuses had increased Mod‐MPI. Mod‐MPI could be used to predict adverse perinatal outcome of FGR fetuses. Mod‐MPI was an effective parameter to supplement vessels’ Doppler parameters in monitoring FGR.