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.

The assessment of fetal cardiac functions in pregnancies with autoimmune diseases: a prospective case-control study

OBJECTIVES

This study aimed to assess the effect of the inflammatory process on fetal cardiac functions in pregnant women with autoimmune diseases (AID).

METHODS

This prospective study included 36 pregnant women with diagnosed AID. Nineteen systemic lupus erythematosus, 12 antiphospholipid syndrome, 5 Sjögren's syndrome, and 72 healthy pregnancies were included. Fetal cardiac functions were evaluated with pulsed-wave, tissue Doppler, and M-mode echocardiography.

RESULTS

Sociodemographic data were similar in both groups. Significant increases were found in tricuspid E (43.5 ± 0.9, p<0.001) and A (59.2 ± 2.2, p<0.001) and E/A (0.74 ± 0.03, p<0.001), E'/A' (0.64 ± 0.15, p<0.001), E/E' (6.5 ± 0.6, p<0.001), and left ventricular myocardial performance index (0.54 ± 0.03, p=0.005). We demonstrated a significant decrease in tricuspid E' (6.7 ± 0.6, p<0.001) and S' (6.9 ± 1, p<0.001) and in TAPSE (7.7 ± 0.5, p=0.002). We also found a significantly prolonged PR interval (130 ± 8, p<0.001). There was a significant increase in E' (6.8, p=0.033) and a significant decrease in E/E' ratio (6.4, p=0.027) in the group using hydroxychloroquine (HCQ) compared to non-users.

CONCLUSIONS

We found that pregnancy with autoimmune diseases affects fetal heart functions. Additionally, hydroxychloroquine may positively affect the heart of AID fetuses. This information might be useful to clinicians in the follow-up of cardiovascular diseases.

Intrahepatic cholestasis of pregnancy and fetal cardiac dysfunction: a systematic review and meta-analysis

OBJECTIVE

Intrahepatic cholestasis of pregnancy is associated with adverse perinatal outcomes. Fetal cardiac dysfunction may be 1 part of the pathophysiology of pregnancies complicated by intrahepatic cholestasis of pregnancy. This systematic review and meta-analysis aimed to evaluate the association between intrahepatic cholestasis of pregnancy and fetal cardiac dysfunction.

DATA SOURCES

Systematic searches were performed on the databases of Medline, Embase, and Cochrane Library (up to March 2, 2023) for studies evaluating fetal cardiac function in pregnancies complicated by intrahepatic cholestasis of pregnancy in addition to the reference lists of included studies.

STUDY ELIGIBILITY CRITERIA

Studies were eligible for inclusion if they assessed the fetal cardiac function by fetal echocardiography in women with intrahepatic cholestasis of pregnancy (mild or severe) and compared with fetuses of healthy pregnant women. The studies published in English were included.

METHODS

The quality of the retrieved studies was assessed using the Newcastle-Ottawa Scale. Data on fetal myocardial performance index, E wave/A wave peak velocities ratio, and PR interval were pooled for the meta-analysis using random-effects models. The results were presented as weighted mean differences and 95% confidence intervals. This meta-analysis was registered with the International Prospective Register of Systematic Reviews (registration number: CRD42022334801).

RESULTS

A total of 14 studies were included in this qualitative analysis. Of note, 10 studies that reported data on fetal myocardial performance index, E wave/A wave peak velocities ratio, and PR interval were included in the quantitative analysis and showed a significant association between intrahepatic cholestasis of pregnancy and fetal cardiac dysfunction. Significantly higher fetal left ventricular myocardial performance index values (weighted mean difference, 0.10; 95% confidence interval, 0.04-0.16) and longer fetal PR intervals (weighted mean difference, 10.10 ms; 95% confidence interval, 7.34-12.86) were revealed in pregnancies complicated by intrahepatic cholestasis of pregnancy. Compared with the situation in pregnancies complicated by mild intrahepatic cholestasis of pregnancy, PR intervals were even longer in pregnancies complicated by severe intrahepatic cholestasis of pregnancy (weighted mean difference, 5.98 ms; 95% confidence interval, 0.20-11.77). There was no significant difference in fetal E wave/A wave peak velocities ratio between the group with intrahepatic cholestasis of pregnancy and the healthy pregnant group (weighted mean difference, 0.01; 95% confidence interval, -0.03 to 0.05).

CONCLUSION

Our findings supported the idea that intrahepatic cholestasis of pregnancy is associated with overall impaired fetal myocardial performance and impaired fetal cardiac conduction system. However, current evidence about the association between fetal cardiac dysfunction and intrahepatic cholestasis of pregnancy-induced stillbirth is lacking. Further studies are needed to reveal the relationship between fetal cardiac dysfunction and adverse perinatal outcomes in pregnancies complicated by intrahepatic cholestasis of pregnancy.

How Automated Techniques Ease Functional Assessment of the Fetal Heart: Applicability of MPI+™ for Direct Quantification of the Modified Myocardial Performance Index

(1) Objectives: In utero functional cardiac assessments using echocardiography have become increasingly important. The myocardial performance index (MPI, Tei index) is currently used to evaluate fetal cardiac anatomy, hemodynamics and function. An ultrasound examination is highly examiner-dependent, and training is of enormous significance in terms of proper application and subsequent interpretation. Future experts will progressively be guided by applications of artificial intelligence, on whose algorithms prenatal diagnostics will rely on increasingly. The objective of this study was to demonstrate the feasibility of whether less experienced operators might benefit from an automated tool of MPI quantification in the clinical routine. (2) Methods: In this study, a total of 85 unselected, normal, singleton, second- and third-trimester fetuses with normofrequent heart rates were examined by a targeted ultrasound. The modified right ventricular MPI (RV-Mod-MPI) was measured, both by a beginner and an expert. A calculation was performed semiautomatically using a Samsung Hera W10 ultrasound system (MPI+™, Samsung Healthcare, Gangwon-do, South Korea) by taking separate recordings of the right ventricle's in- and outflow using a conventional pulsed-wave Doppler. The measured RV-Mod-MPI values were assigned to gestational age. The data were compared between the beginner and the expert using a Bland-Altman plot to test the agreement between both operators, and the intraclass correlation was calculated. (3) Results: The mean maternal age was 32 years (19 to 42 years), and the mean maternal pre-pregnancy body mass index was 24.85 kg/m² (ranging from 17.11 to 44.08 kg/m²). The mean gestational age was 24.44 weeks (ranging from 19.29 to 36.43 weeks). The averaged RV-Mod-MPI value of the beginner was 0.513 ± 0.09, and that of the expert was 0.501 ± 0.08. Between the beginner and the expert, the measured RV-Mod-MPI values indicated a similar distribution. The statistical analysis showed a Bland-Altman bias of 0.01136 (95% limits of agreement from -0.1674 to 0.1902). The intraclass correlation coefficient was 0.624 (95% confidence interval from 0.423 to 0.755). (4) Conclusions: For experts as well as for beginners, the RV-Mod-MPI is an excellent diagnostic tool for the assessment of fetal cardiac function. It is a time-saving procedure, offers an intuitive user interface and is easy to learn. There is no additional effort required to measure the RV-Mod-MPI. In times of reduced resources, such assisted systems of fast value acquisition represent clear added value. The establishment of the automated measurement of the RV-Mod-MPI in clinical routine should be the next level in cardiac function assessment.

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.

Comparison of Parameters of Fetal Doppler Echocardiography Between Mothers with and Without Diabetes

BACKGROUND

The current study aimed to compare fetal myocardial function and ventricular thickness in diabetic and normal pregnancies.

METHODS

Women with singleton pregnancies in the second or third trimester who were referred for routine prenatal or anomaly ultrasounds within March 2020 to February 2021 were enrolled in the study. Women with a positive history of overt or gestational diabetes mellitus (GDM) were considered the case group (n = 50), and women without GDM were considered the control group (n = 50). The study did not include women with multifetal pregnancy, hypertension, intrauterine growth retardation, and polyhydramnios. A complete fetal Doppler echocardiography was performed to measure isovolumic relaxation time (IVRT), left myocardial performance index (MPI), E/A ratio, right and left ventricular wall thickness, and end-diastolic interventricular septal thickness (IVST). The data were analyzed using three types of decision tree (DT) algorithms, and the performance of each DT was measured on the testing dataset.

RESULTS

The frequency of IVRT > 41 milliseconds was significantly higher in the case group than in the control group. The mean MPI values were 0.53 ± 0.15 and 0.43 ± 0.09 (P < 0.05), respectively, and the mean IVST values were 3.3 ± 1.11 and 2.49 ± 0.55 mm (P < 0.05) in the case and control groups, respectively, but not different between the subjects with overt or GDM (P > 0.05). Additionally, in the case group, the mean left MPI values were 0.57 ± 0.18 and 0.49 ± 0.12 in participants with poor and good glycemic control, respectively (P = 0.12).

CONCLUSIONS

Complete prenatal echocardiography performed in the second or third trimester is an appropriate tool for the diagnosis of fetal cardiac dysfunction in diabetic mothers and is suggested to perform for diabetic mothers, even those with good glycemic control.

Cardiotocography in Obstetrics: New Solutions for "Routine" Technology

This work is devoted to the problems of one of the most common screening examinations used in medical practice: fetal cardiotocography (CTG). The technology of ultrasonic monitoring of fetal heart rate (HR) variations has been used for more than 70 years. During this time, it has undergone many upgrades and has been characterized several times as a hopelessly outdated routine technology. Over the past 5-7 years, many in-depth studies and review papers on cardiotocography have appeared, which revealed both the problems and prospects of the technology. Basically, hopes are associated with artificial intelligence, which should increase the accuracy of the analysis of initially inaccurate measurements obtained using ultrasonic testing. At the same time, after the introduction of pulsed operating modes and the appearance of multi-chip sensors, the quality of the original signal remains practically unchanged. This circumstance makes the prospects of the technology very problematic. However, until now, there has not been a reliable replacement for this screening, which is equally safe, non-invasive, and accessible to a wide range of specialists, medical institutions, and patients. The paper discusses and substantiates proposals for improving the technology based on original (different from traditional CTG) methods of processing information received from ultrasonic sensors, which, in the author's opinion, allow for solving the main problems of CTG: identifying the correct direction of radiation to the fetal heart and to reliably evaluate beat-to-beat heart rate.

Efficacy of fetal left ventricular modified myocardial performance index in predicting adverse perinatal outcomes in intrahepatic cholestasis of pregnancy

OBJECTIVE

This study aimed to evaluate the effectiveness of fetal left ventricular modified myocardial performance index in predicting adverse perinatal outcomes for intrahepatic cholestasis of pregnancy.

METHODS

A cross-sectional study was conducted, including 51 women with intrahepatic cholestasis of pregnancy and 80 healthy controls. Using Doppler ultrasonography, E-wave, A-wave, isovolumetric contraction time, isovolumetric relaxation time, and ejection time were recorded and the left ventricular modified myocardial performance index was measured.

RESULTS

Findings showed that the mean left ventricular modified myocardial performance index, isovolumetric contraction time, and isovolumetric relaxation time values were statistically significantly higher while the ejection time and E/A ratios were statistically significantly lower in the intrahepatic cholestasis of pregnancy group than the control group. In the intrahepatic cholestasis of pregnancy group, a statistically significant positive correlation was found between left ventricular modified myocardial performance index and adverse perinatal outcomes in the intrahepatic cholestasis of pregnancy group (r=0.478, p<0.001), while a statistically significant negative correlation was found between the E/A ratio and adverse perinatal outcomes (r=-0.701, p<0.001).

CONCLUSIONS

For intrahepatic cholestasis of pregnancy cases, high fetal left ventricular modified myocardial performance index values were an indicator of ventricular dysfunction, and this correlated with negative perinatal outcomes.

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.

Left myocardial performance index in monochorionic diamniotic twin pairs complicated by selective fetal growth restriction with abnormal umbilical artery Doppler

OBJECTIVE

To evaluate left myocardial performance index (MPI) and its time intervals in monochorionic diamniotic (MCDA) twin pairs complicated by selective fetal growth restriction (sFGR) with abnormal (persistent -type II- or intermittent -type III- absent or reversed end-diastolic flow) umbilical artery Doppler.

METHODS

Retrospective study including 16 MCDA twin pairs with sFGR type II, 26 MCDA twin pairs with sFGR type III and 42 gestational age-matched uncomplicated MCDA twin pairs in a single tertiary center. Left isovolumetric contraction time (ICT), ejection time (ET), and isovolumetric relaxation time (IRT) were measured and MPI calculated by conventional Doppler at diagnosis of sFGR.

RESULTS

In sFGR type II, the smaller twin had shorter ET and prolonged IRT and MPI, while the larger twin showed prolonged ICT and MPI as compared to uncomplicated MCDA twins. In sFGR type III, the smaller twin had shorter ICT and ET, while the larger twin showed prolonged ICT, IRT, and MPI in comparison to controls.

CONCLUSION

A differential pattern of MPI time intervals could be observed in MCDA twins with sFGR type II and III. All twins had echocardiographic signs of pressure/volume overload, except the smaller twin type III with shorter systolic times probably reflecting reduced volume load.

Echocardiographic assessment of fetal cardiac function in the uterine artery ligation rat model of IUGR

BACKGROUND

Intrauterine growth restriction (IUGR) leads to cardiac dysfunction and adverse remodeling of the fetal heart, as well as a higher risk of postnatal cardiovascular diseases. The rat model of IUGR, via uterine artery ligation, is a popular model but its cardiac sequelae is not well investigated. Here, we performed an echocardiographic evaluation of its cardiac function to determine how well it can represent the disease in humans.

METHODS

Unilateral uterine artery ligation was performed at embryonic day 17 (E17) and echocardiography was performed at E19 and E20.

RESULTS

Growth-restricted fetuses were significantly smaller and lighter, and had an higher placenta-to-fetus weight ratio. Growth-restricted fetal hearts had reduced wall thickness-to-diameter ratio, indicating left ventricular (LV) dilatation, and they had elevated trans-mitral and trans-tricuspid E/A ratios and reduced left and right ventricular fractional shortening (FS), suggesting systolic and diastolic dysfunction. These were similar to human IUGR fetuses. However, growth-restricted rat fetuses did not demonstrate head-sparing effect, displayed a lower LV myocardial performance index, and ventricular outflow velocities were not significantly reduced, which were dissimilar to human IUGR fetuses.

CONCLUSIONS

Despite the differences, our results suggest that this IUGR model has significant cardiac dysfunction, and could be a suitable model for studying IUGR cardiovascular physiology.

IMPACT

Animal models of IUGR are useful, but their fetal cardiac function is not well studied, and it is unclear if they can represent human IUGR fetuses. We performed an echocardiographic assessment of the heart function of a fetal rat model of IUGR, created via maternal uterine artery ligation. Similar to humans, the model displayed LV dilatation, elevated E/A ratios, and reduced FS. Different from humans, the model displayed reduced MPI, and no significant outflow velocity reduction. Despite differences with humans, this rat model still displayed cardiac dysfunction and is suitable for studying IUGR cardiovascular physiology.

Improvement of cardiac function in fetuses with growth restriction following antenatal betamethasone administration: fact or artifact?

INTRODUCTION

Use of corticosteroids for fetal lung maturation has reduced the perinatal mortality/morbidity from prematurity related complications. There is a paucity of studies evaluating the effect of steroid administration on the fetal circulation and cardiac function in fetal growth restriction (FGR). The aim of the study was to assess changes in fetal Doppler indices and cardiovascular function in pregnancies complicated with FGR after administration of betamethasone.

METHODS

This was a prospective study conducted in a tertiary care research center between July 2017 and May 2018. Pregnant women with FGR between 28 and 36 weeks' gestation, who were scheduled to receive betamethasone (two doses of 12 mg, 24 h apart) were recruited. Fetal cardiovascular function in fetuses FGR was assessed immediately before first dose and once between 6 and 24 h after the second dose of betamethasone by the same operator. Wilcoxon matched-pairs signed-rank test or paired t-tests were used to compare parameters before and after corticosteroid exposure.

RESULTS

Fifty cases with FGR were evaluated before and after administration of betamethasone, at mean gestational age of 34.6 ± 2.0 weeks. Fetal heart rate (148.78 ± 9.10 versus 144.73 ± 9.61, p < .001), left heart myocardial performance index ([MPI], 0.66 ± 0.06 versus 0.55 ± 0.09, p ≤ .001) and right heart MPI (0.65 ± 0.04 versus 0.63 ± 0.04, p .016) showed improvement after steroids. Left heart isovolumic relaxation and contraction indices along with ejection time of both sides showed a small but statistically significant improvement (p < .001), but other fetal cardiac functional and Doppler indices remain unchanged after steroids.

CONCLUSIONS

Fetal heart rate, cardiac MPI, left sided isovolumic indices showed an improvement after betamethasone administration. Follow up studies are needed to ascertain whether these effects persist in the long term and to determine whether these are beneficial to a growth restricted fetuses.

Left Ventricular Isovolumetric Relaxation Time Is Prolonged in Fetal Long-QT Syndrome

BACKGROUND

Long-QT syndrome (LQTS), an inherited cardiac repolarization disorder, is an important cause of fetal and neonatal mortality. Detecting LQTS prenatally is challenging. A fetal heart rate (FHR) less than third percentile for gestational age is specific for LQTS, but the sensitivity is only ≈50%. Left ventricular isovolumetric relaxation time (LVIRT) was evaluated as a potential diagnostic marker for fetal LQTS.

METHODS AND RESULTS

LV isovolumetric contraction time, LV ejection time, LVIRT, cycle length, and FHR were measured using pulsed Doppler waveforms in fetuses. Time intervals were expressed as percentages of cycle length, and the LV myocardial performance index was calculated. Single measurements were stratified by gestational age and compared between LQTS fetuses and controls. Receiver-operator curves were performed for FHR and normalized LVIRT (N-LVIRT). A linear mixed-effect model including multiple measurements was used to analyze trends in FHR, N-LVIRT, and LV myocardial performance index. There were 33 LQTS fetuses and 469 controls included. In LQTS fetuses, the LVIRT was prolonged in all gestational age groups (P<0.001), as was the N-LVIRT. The best cutoff to diagnose LQTS was N-LVIRT ≥11.3 at ≤20 weeks (92% sensitivity, 70% specificity). Simultaneous analysis of N-LVIRT and FHR improved the sensitivity and specificity for LQTS (area under the curve=0.96; 95% confidence interval, 0.82-1.00 at 21-30 weeks). N-LVIRT, LV myocardial performance index, and FHR trends differed significantly between LQTS fetuses and controls through gestation.

CONCLUSIONS

The LVIRT is prolonged in LQTS fetuses. Findings of a prolonged N-LVIRT and sinus bradycardia can improve the prenatal detection of fetal LQTS.

The value of echocardiography and Doppler in the prediction of fetal demise after laser coagulation for TTTS: A systematic review and meta-analysis

This study aimed to investigate the value of echocardiography and Doppler before fetoscopic laser coagulation for twin‐twin transfusion syndrome (TTTS) in the prediction of intrauterine fetal demise (IUFD). We performed a systematic review and meta‐analysis to compare preoperative parameters between fetuses with and without demise after laser surgery. Eighteen studies were included. Recipient twins have an increased risk of demise in case of preoperative absent/reversed flow (A/REDF) in the umbilical artery (odds ratio [OR] 2.76, 95% confidence interval [CI], 1.78‐4.28), absent or reversed a‐wave in the ductus venosus (OR 2.32, 95% CI, 1.70‐3.16), or a middle cerebral artery peak systolic velocity > 1.5 multiples of the median (MoM) (OR 7.59, 95% CI, 2.56‐22.46). In donors, only A/REDF in the umbilical artery (OR 3.40, 95% CI, 2.68‐4.32) and absent or reversed a‐wave in the ductus venosus (OR 1.66, 95% CI, 1.12‐2.47) were associated with IUFD. No association was found between donor‐IUFD and preoperative myocardial performance index (MPI). Two studies found an association between abnormal MPI and recipient demise. With this study, we have identified a set of preoperative Doppler parameters predictive of fetal demise after laser surgery. More research is needed to assess the utility of preoperative echocardiographic parameters such as the MPI in predicting IUFD.

What's already known about this topic?

Doppler parameters are associated with fetal demise after laser surgery.

Echocardiographic parameters are currently not used in risk stratification.

What does this study add?

A more extensive set of preoperative Doppler parameters is defined to predict post‐laser fetal demise.

The utility of preoperative echocardiographic parameters such as the MPI in predicting fetal demise remains unclear.

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.

Assessment of strain and dyssynchrony in normal fetuses using speckle tracking echocardiography - comparison of three different ultrasound probes

OBJECTIVE

To evaluate segmental left (LV-S) and right (RV-S) ventricular strain as well as longitudinal mechanical myocardial dyssynchrony as a time difference between peaks in strain of both ventricles in fetuses (two-chamber-dyssynchrony, 2C-DYS) using speckle tracking echocardiography (STE). The aim of our study was to evaluate the influence of data acquisition on the results of STE measurement using different ultrasound probes.

METHODS

We prospectively recorded cardiac cycles of four-chamber views of 56 normal fetuses with three different ultrasound probes and analyzed them offline with speckle tracking imaging software. Furthermore, we looked at a possible influence of heartbeat variability (beat-to-beat variability).

RESULTS

The evaluation of the parameters was feasible with all three probes in 53 cases. There was no influence of heartbeat variability and no noticeable differences in 2C-DYS, LV-S and RV-S in all cases and for all three probes determined.

CONCLUSION

Assessment of strain and dyssynchrony using STE with three different probes is comparable. Further research is needed to validate dyssynchrony as a predictor for fetal outcome.

Cardiotocography and beyond: a review of one-dimensional Doppler ultrasound application in fetal monitoring

One-dimensional Doppler ultrasound (1D-DUS) provides a low-cost and simple method for acquiring a rich signal for use in cardiovascular screening. However, despite the use of 1D-DUS in cardiotocography (CTG) for decades, there are still challenges that limit the effectiveness of its users in reducing fetal and neonatal morbidities and mortalities. This is partly due to the noisy, transient, complex and nonstationary nature of the 1D-DUS signals. Current challenges also include lack of efficient signal quality metrics, insufficient signal processing techniques for extraction of fetal heart rate and other vital parameters with adequate temporal resolution, and lack of appropriate clinical decision support for CTG and Doppler interpretation. Moreover, the almost complete lack of open research in both hardware and software in this field, as well as commercial pressures to market the much more expensive and difficult to use Doppler imaging devices, has hampered innovation. This paper reviews the basics of fetal cardiac function, 1D-DUS signal generation and processing, its application in fetal monitoring and assessment of fetal development and wellbeing. It also provides recommendations for future development of signal processing and modeling approaches, to improve the application of 1D-DUS in fetal monitoring, as well as the need for annotated open databases.

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.

Differential Changes in Myocardial Performance Index and Its Time Intervals in Donors and Recipients of Twin-to-Twin Transfusion Syndrome before and after Laser Therapy

OBJECTIVE

To evaluate left myocardial performance index (MPI) and time intervals in fetuses with twin-to-twin transfusion syndrome (TTTS) before and after laser surgery.

METHODS

Fifty-one fetal pairs with TTTS and 47 uncomplicated monochorionic twin pairs were included. Left ventricular isovolumetric contraction time (ICT), ejection time (ET), and isovolumetric relaxation time (IRT) were measured using conventional Doppler.

RESULTS

Recipients showed prolonged ICT (46 ± 12 vs. 31 ± 8 vs. 30 ± 5 ms; p < 0.001) and IRT (51 ± 9 vs. 43 ± 8 vs. 43 ± 5 ms; p < 0.001) and higher MPI (0.57 ± 0.12 vs. 0.47 ± 0.09 vs. 0.44 ± 0.05; p < 0.001) than donors and controls. Donors showed shorter ET than recipients and controls (157 ± 12 vs. 169 ± 10 vs. 168 ± 10 ms; p < 0.001) and higher MPI than controls (0.47 ± 0.09 vs. 0.44 ± 0.05; p = 0.006). Preoperative MPI changes were observed in all TTTS stages. Time intervals partially improved after surgery.

CONCLUSION

Donor and recipient twins had higher MPI due to different changes in the time intervals, possibly reflecting the state of hypovolemia in the donor and hypervolemia and pressure overload in the recipient.

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.

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.

[High-frequency echocardiography for assessment of regional wall motion abnormality and cardiac function in mice with myocardial infarction]

OBJECTIVE

To evaluate the value of high-frequency echocardiography in assessing cardiac structure and function in a mouse model of myocardial infarction.

METHODS

Twenty-five C57BL/6 mice were randomly divided into sham-operated group (n=10) and myocardial infarction model group (n=15) established by ligation of the left anterior descending artery. The cardiac structure, regional wall motion and cardiac function of mice were examined with pulsed wave Doppler (PWD), tissue Doppler imaging (TDI), EKV and M-mode echocardiography 3 days before and at 1 week after the operation. The histological changes and myocardial structure of the heart were observed at 1 week after the operation.

RESULTS

High-frequency echocardiography and HE staining detected obvious myocardial infarction in the mice in the model group. Compared with the sham-operated mice, the mice with myocardial infarction showed significant left ventricular expansion, obvious thinning of the ventricular wall, and significantly decreased ventricular systolic function and diastolic function with regional wall motion abnormality and ventricular remodeling.

CONCLUSION

s 2D-type echocardiography combined with M-mode, PWD, TDI and EKVTM for allows accurate and sensitive detection of the loci and severity of myocardial infarction to provide important evidence for clinical diagnosis and treatment of myocardial infarction.

Beat-to-beat variability of fetal myocardial performance index

OBJECTIVES

To determine whether there is beat-to-beat (BTB) variability in the fetal left myocardial performance index (MPI), as evaluated by an automated system, and whether there is a correlation between MPI and fetal heart rate (FHR).

METHODS

This was a prospective cross-sectional study of uncomplicated, morphologically normal, singleton pregnancies at 20-38 weeks' gestation. Multiple cineloops for left MPI measurement were acquired during a single examination of each fetus. Raw cineloop data were analyzed by our automated MPI system (intraclass correlation coefficient of 1.0 for any given waveform) to produce a set of MPIs. The corresponding instantaneous FHR was measured for each individual cardiac cycle for which MPI was calculated.

RESULTS

Data from 29 fetuses were analyzed; mean MPI was 0.52, mean FHR was 150 beats per min and the median number of cardiac cycles examined per fetus was 70 (interquartile range, 31-115). Marked BTB variability was noted; median coefficient of variation was 10% (range, 5.5-13.9%). FHR was weakly correlated with absolute MPI (r = 0.22; P < 0.05). BTB variation in MPI as a percentage of the mean MPI was not significantly correlated with FHR (r = 0.031; P = 0.146). When standard error of the mean of all MPI values was divided by the mean for each case, it showed that at least four cardiac cycles should be averaged to reduce MPI variability to approximately ± 5%.

CONCLUSION

There is significant BTB variability in fetal left MPI, which has an overall weak correlation with FHR. This could be a factor affecting the consistency of MPI values reported by different research groups. Variability would be reduced by averaging 4-5 cardiac cycles per fetus. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

Evaluation of an automated fetal myocardial performance index

OBJECTIVE

To compare automated measurements of the fetal left myocardial performance index (MPI) with manual measurements for absolute value, repeatability and waveform acceptability.

METHODS

This was a multicenter international online study using images from uncomplicated, morphologically normal singleton pregnancies (16-38 weeks' gestation). Single Doppler ultrasound cardiac cycle images of 25 cases were selected, triplicated and randomized (n = 75). Six senior observers, unaware of the repetition of images, manually calculated MPI for each waveform and the results were compared with automation. Intraobserver repeatability and interobserver reproducibility were assessed using intraclass correlation coefficients (ICCs) and 95% CI. The agreement between each observer's manual MPI measurements and corresponding automated measurements was evaluated using Bland-Altman plots and ICCs with 95% CI. The degree of variation between experts in the classification of fetal MPI waveform quality was assessed using individual cardiac cycle left MPI images previously classified by two authors as 'optimal', 'suboptimal' or 'unacceptable', with 30 images selected for each quality group. Ten images in each category were duplicated and the resulting 120 images were randomized and then classified online by five observers. The kappa statistic (κ) was used to demonstrate interobserver and intraobserver agreement and agreement of classifications by the five observers.

RESULTS

The automated measurement software returned the same value for any given image, resulting in an ICC of 1.00. Manual measurements had intraobserver repeatability ICC values ranging from 0.69 to 0.97, and the interobserver reproducibility ICC was 0.78. Comparison of automated vs manual MPI absolute measurements for each observer gave ICCs ranging from 0.77 to 0.96. Interobserver image quality classification agreement gave k = 0.69 (P < 0.001), and the intraobserver agreement was variable (κ ranging from 0.40 to 0.81).

CONCLUSIONS

Automated fetal MPI provides superior repeatability and reproducibility to manual methodology. Additionally, experts vary significantly when classifying suitability of fetal MPI waveforms. Automated MPI may facilitate clinical translation by removing human subjectivity. Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd.

Zidovudine treatment in HIV-infected pregnant women is associated with fetal cardiac remodelling

OBJECTIVE

To evaluate the cardiac structure and function of the fetuses of pregnant women with HIV infection on combined antiretroviral treatment (cART) and the HIV-related and nonrelated determinants of abnormal findings.

DESIGN

A prospective cohort study including 42-noninfected fetuses from HIV pregnant women on cART and 84 fetuses from non-HIV-infected women.

METHODS

Fetal echocardiography was performed at 26-32 weeks of pregnancy to assess cardiac structure and function. The impact of maternal and perinatal factors on fetal cardiac remodelling was evaluated by multivariate regression analysis.

RESULTS

Fetuses from HIV pregnant women on cART presented larger hearts and pericardial effusion together with thicker myocardial septal walls (mean 3.56 mm (SD 0.88) vs non-HIV mean 2.75 mm (SD 0.77); P = 0.002) and smaller left ventricular cavities (10.81 mm (SD 2.28) vs 12.3 mm (SD 2.54); P = 0.033). Fetuses from HIV women also presented signs of systolic (mitral systolic annular peak velocity 5.85 cm/s (SD 0.77) vs non-HIV 6.25 cm/s (SD 0.97); P = 0.007) and diastolic (isovolumic relaxation time 52 ms (SD 8.91) vs non-HIV 45 ms (SD 7.98); P < 0.001) dysfunction. In the multivariate analysis, maternal treatment with zidovudine was the only factor significantly associated with fetal cardiac changes (P = 0.014).

CONCLUSION

Fetuses from HIV-infected mothers on cART have cardiac remodelling and dysfunction, which might explain the cardiovascular changes described in childhood. Fetal cardiac remodelling was essentially associated with maternal treatment with zidovudine which challenges its use during pregnancy.

Arteriovenous malformation of vein of Galen as a rare non-hypoxic cause of changes in fetal heart rate pattern during labor

The aim of this case report is to describe a rare non-hypoxic cause of pathological changes in fetal heart rate pattern during labor, and to determine management, including a description of important prenatal aspects when pathologic cardiotocographic recording is performed during labor. A fetus with rare arteriovenous malformation of the vein of Galen, which represents less than 1% of all intracranial arteriovenous malformations, was monitored by intrapartum external cardiotocography in the 37 + 5 gestational week. The baby was born by cesarean section because of signs of imminent intrauterine hypoxia on cardiotocography. However, metabolic acidosis was not confirmed in umbilical cord blood sampling. Despite intensive neonatal care management, the newborn died 31 h after delivery because of progressive cardiac decompensation, hypotension and multi-organ failure. Precise diagnosis of the abovementioned pathology, a pre-labor plan for delivery and postnatal prognosis assessment can significantly contribute to the avoidance of a misdiagnosis of fetal hypoxia and unnecessary operative delivery with marked medico-legal consequences.

Monitoring intrahepatic cholestasis of pregnancy using the fetal myocardial performance index: a cohort study

OBJECTIVE

To investigate use of the fetal myocardial performance index (MPI) in assessing intrahepatic cholestasis of pregnancy (ICP).

METHODS

This was a cohort study including cross-sectional and longitudinal data from 31 women with ICP recruited from June 2012 to March 2014. Fetal left, right and delta MPI (LMPI, RMPI and DMPI), and routine measures of fetal growth and wellbeing, were obtained at each ultrasound examination. Results were evaluated with respect to gestational age (GA)-adjusted reference intervals, level of maternal serum bile acid (SBA) and fetal outcome. Lower SBA (≥ 7.5 and < 40 μmol/L) and high SBA (≥ 40 μmol/L) subgroups of cases were defined for the analysis.

RESULTS

A total of 51 ultrasound examinations were performed in 33 fetuses. The mean LMPI, and means of its isovolumetric relaxation time (IRT) and isovolumetric contraction time (ICT) components were significantly higher in all subgroups of cases of ICP relative to the normal reference mean. Considering only the first examination in each case of ICP, IRT was significantly more prolonged in the high SBA group (n = 10) in comparison to the lower SBA group (n = 23) (52.7 ± 8.0 ms vs 47.3 ± 4.8 ms, P = 0.02), and both IRT (r = 0.538, P = 0.001) and LMPI (r = 0.367, P = 0.036) were significantly correlated with SBA concentration. The proportion of high SBA cases with LMPI, RMPI or DMPI > 2 SD above the GA-adjusted reference mean was not significantly greater than for the lower SBA group. On analysis of all data from those cases with more than one examination, no significant correlation was found between SBA concentration and any of the MPI variables.

CONCLUSIONS

LMPI values increase above the population GA-adjusted mean in cases of ICP, particularly amongst women with higher SBA. A significant correlation between IRT and LMPI at initial examination and increasing SBA concentration was found. A future multicenter prospective study may clarify the prognostic utility of MPI in ICP.

Comparison of Two Different Ultrasound Systems for the Evaluation of Tissue Doppler Velocities in Fetuses

Introduction: Recent studies have reported variations of up to 30% between different ultrasound machines for tissue Doppler imaging (TDI), a problem that can significantly impact clinical diagnosis, patient management and research studies. The objective of this study was to assess repeatability and agreement between fetal myocardial peak velocities evaluated by TDI with two different ultrasound systems. Materials and Methods: Systolic (S'), early (E') and late (A') diastolic myocardial peak velocities at mitral and tricuspid annuli as well as at the basal septum were evaluated by spectral TDI in 150 fetuses using two different ultrasound systems: Siemens Antares (Siemens Medical Systems, Malvern, Pa., USA) and Vivid Q (General Electric Healthcare, Horten, Norway). A method comparison study was performed, calculating intraclass correlation coefficients (ICC), and agreement was assessed by Bland-Altman plots. Results: Annular peak velocities showed lower values when measured by Vivid Q compared to values measured by Siemens Antares. ICC ranged from 0.07 (septal S') to 0.33 (right A'), showing very poor repeatability for clinical application. Agreement between the two systems was also poor, with high coefficients of variation for all measurements. Conclusions: Fetal annular peak velocities obtained with different ultrasound systems are not directly comparable. This is consistent with previous data in adults and warrants the need of system-specific reference values, suggesting that the same ultrasound machine should be used for longitudinal follow-up.

The Fetal Modified Myocardial Performance Index: Is Automation the Future?

The fetal modified myocardial performance index (Mod-MPI) is a noninvasive, pulsed-wave Doppler-derived measure of global myocardial function. This review assesses the progress in technical refinements of its measurement and the potential for automation to be the crucial next step. The Mod-MPI is a ratio of isovolumetric to ejection time cardiac time intervals, and the potential for the left ventricular Mod-MPI as a tool to clinically assess fetal cardiac function is well-established. However, there are wide variations in published reference ranges, as (1) a standardised method of selecting cardiac time intervals used in Mod-MPI calculation has not been established; (2) cardiac time interval measurement currently requires manual, inherently subjective placement of callipers on Doppler ultrasound waveforms; and (3) ultrasound machine settings and ultrasound system type have been found to affect Mod-MPI measurement. Collectively these factors create potential for significant inter- and intraobserver measurement variability. Automated measurement of the Mod-MPI may be the next key development which propels the Mod-MPI into routine clinical use. A novel automated system of Mod-MPI measurement is briefly presented and its implications for the future of the Mod-MPI in fetal cardiology are discussed.