Right and left ventricular 24-segment sphericity index is abnormal in small-for-gestational-age fetuses

Factors Predicting Fetal Growth Restriction and Fetal Cardiac Remodeling

Objective

This study aimed to investigate factors influencing fetal growth restriction (FGR) occurrence and assess the clinical significance of fetal cardiac parameters in FGR prediction.

Methods

Pregnant women with clinically suspected FGR (n=179) and uncomplicated pregnancies (n=53) were included. All had undergone routine obstetric ultrasonography and fetal echocardiography. Umbilical artery flow (UAF) and fetal cardiac parameters (left atrial transverse diameter (LAd), right atrial transverse diameter (RAd), left ventricular transverse diameter (LVd), right ventricular transverse diameter (RVd), foramen ovale width, atrial septum diameter, interventricular septal thickness, left ventricular posterior wall thickness, right ventricular free wall thickness, aortic diameter, pulmonary artery diameter, mitral E velocity, mitral A velocity, tricuspid E velocity, tricuspid A velocity, aortic valve peak flow velocity, and pulmonary valve peak flow velocity) were detected. Follow up was conducted until birth, various fetal clinical parameters were collected: maternal body mass index (BMI), hypertensive disorders complicating pregnancy (HDCP), abnormal umbilical artery flow, placental or umbilical cord anomalies, low amniotic fluid volume, preterm birth, emergency cesarean delivery, maternal height, maternal age, gestational diabetes mellitus (GDM), hypothyroidism, assisted reproductive technology (ART), parity, and neonatal gender. Participants were categorized into confirmed FGR (n=119) and control (n=113) groups based on neonatal birth weight.

Results

Significant differences were observed between groups in maternal BMI, HDCP, abnormal UAF, placental or umbilical cord anomalies, low amniotic fluid volume, preterm birth, and emergency cesarean delivery. FGR was positively related to abnormal UAF, placental or umbilical cord anomalies, preterm birth and emergency cesarean delivery and negatively to maternal BMI (r=-0.276). Compared to the control group, the FGR group exhibited significantly larger RAd, RVd, RA/LA, and RV/LV.

Conclusion

Fetal growth-restricted fetuses have enlarged right heart structures. Fetal cardiac examinations are valuable for early FGR diagnosis, potentially improving neonatal body weight and reducing adverse pregnancy outcomes.

Evaluation of fetal heart size, morphology and function with fetal growth restriction using fetal HQ

BACKGROUND

Fetal growth restriction (FGR) is associated with various perinatal complications. Limited research has focused on the fetal heart in the context of FGR. This study aimed to investigate the application value of fetal heart quantification (HQ) technology in evaluating the size, morphology, and function of the heart in FGR.

METHODS

A total of 31 fetuses diagnosed with FGR in our hospital from April 2022 to May 2024 were included, alongside another 31 normal fetuses matched for gestational age as the control group. Ultrasound Doppler parameters of the middle cerebral artery (MCA), umbilical artery (UA), venous catheter, and fetal HQ parameters were collected for comparative analysis, and perinatal data were followed up.

RESULTS

Fetuses with FGR exhibited significant differences in various parameters of the MCA and UA compared to the control group (P < 0.05). The four-chamber view end-diastolic transverse width, end-diastolic area, left ventricular (LV) end-diastolic area, end-systolic area, end-systolic length, end-diastolic volume, end-systolic volume, and right ventricular (RV) end-systolic area in the FGR group were significantly lower than those in the control group (P < 0.05). In the 24-segment analysis, the LV fractional shortening in the FGR group was greater than in the control group at segments 12 to 14, while the end-diastolic diameter (ED) at segments 5 to 13 of the LV and segments 1 to 14 of the RV were smaller than those in the control group, with statistical significance (P < 0.05). Analysis of each subgroup indicated that fractional shortening (FS) in the early-onset group was significantly greater than in the late-onset group at RV segments 2 to 8. LV-ED at segments 1 to 15 and RV-ED at segments 1 to 16 were significantly smaller in the early-onset group than in the control group, and LV ED segments 20 to 21 were significantly smaller in the early-onset group compared to the late-onset group (P < 0.05). FS in the mild group was significantly larger than in the normal group at LV segments 10 to 16. The severe group exhibited significantly smaller LV segment 2 to 11 ED and the mild group showed smaller RV segments 1 to 13 compared to the control group (P < 0.05).

CONCLUSIONS

Fetal HQ is a promising technique for evaluating the cardiac function, size, and morphology in cases of FGR.

Association of Amniotic Fluid Volume and Fetal Cardiac and Cerebrovascular Parameters in Fetal Growth Restriction

OBJECTIVES

To investigate the prevalence of oligohydramnios, brain sparing, and cardiac dysfunction among a cohort of fetal growth restriction (FGR).

METHODS

To assess the prevalence of oligohydramnios amongst a large sample of FGR fetuses, we screened a database of ultrasounds of FGR pregnancies from our maternal-fetal medicine clinics (clinical cohort) for diminished amniotic fluid volume. Using a threshold of a maximum vertical pocket (MVP) of <2 cm for "oligohydramnios," and 2 to 3 cm as a "reduced fluid" group, trends of Doppler values and cardiac parameters were assessed from pregnancies in an ongoing research study (comprehensive cohort).

RESULTS

In the clinical cohort, oligohydramnios was identified in only 2/229 (0.8%) and reduced fluid in 19/229 (8%). In the comprehensive cohort, oligohydramnios was seen in 3/126 (2.3%) and reduced fluid in 14/126 (11.1%). A high rate of cardiac and Doppler abnormalities were observed in the oligohydramnios group of the comprehensive cohort. The patients with oligohydramnios had a distinctly different cardiac phenotype with small (2/3 with cardiac area <5th%) (P = 0.01) and round (3/3 with global sphericity index <5th%) (P = 0.02) hearts.

CONCLUSION

Oligohydramnios, when present with FGR, is accompanied by high rates of cerebral and cardiovascular abnormalities.

Fetal 24-Segment Sphericity Index and Ventricular Fractional Shortening Between 12 and 20 Weeks of Gestation

BACKGROUND

Although the fetal sphericity index (SI) and fractional shortening (FS) of 24 transverse segments have been previously reported after the 20th gestational week, there have been no reports during the first and early second trimester.

OBJECTIVE

This study aimed to clarify the SI and FS of 24 transverse segments in normal fetuses before the 20th gestational week.

METHODS

A total of 101 normal fetuses aged between 12 and 20 gestational weeks were examined. The displacement of the ventricular endocardium during the cardiac cycle was computed using speckle-tracking software (GE Healthcare, Milwaukee, WI). We analyzed the length of 24 end-diastolic lateral segments and the end-diastolic basal (seg1-6)- middle (Seg7-15)-apical (Seg16-24) distribution from the base to the apex of each ventricle, according to the method described by DeVore et al. The SI and FS were computed for each of the 24 segments by dividing the mid-basal-apical length by the transverse size.

RESULTS

The SI for each segment was independent of the gestational age. The SI of the right ventricle was significantly lower than that of the left ventricle for segments 1-14, suggesting that the right ventricle was more spherical than the left ventricle in the basal segment only. The FS of the right ventricle was significantly lower than that of the left ventricle in segments 1 to 2 and 13 to 24.

CONCLUSION

The morphology of the ventricles before 20 weeks of gestation differs from that between 20 and 40 weeks of gestation. This difference may be related to myocardial densification or performance.

Prediction of fetal growth restriction and small for gestational age by ultrasound cardiac parameters

OBJECTIVE

Prediction of fetal growth restriction (FGR) and small of gestational age (SGA) infants by using various ultrasound cardiac parameters in a logistic regression model.

METHODS

In this retrospective study we obtained standardized ultrasound images of 357 fetuses between the 20th and 39th week of gestation, 99 of these fetuses were between the 3rd and 10th growth percentile, 61 smaller than 3rd percentile and 197- appropriate for gestational age over the 10th percentile (control group). Several cardiac parameters were studied. The cardiothoracic ratio and sphericity of the ventricles was calculated. A binary logistic regression model was developed for prediction of growth restriction using the cardiac and biometric parameters.

RESULTS

There were noticeable differences between the control and study group in the sphericity of the right ventricle (p = 0.000), left and right longitudinal ventricle length (pright = 0.000, pleft = 0.000), left ventricle transverse length (p = 0.000), heart diameter (p = 0.002), heart circumference (p = 0.000), heart area (p = 0.000), and thoracic diameter limited by the ribs (p = 0.002). There was no difference of the cardiothoracic ratio between groups. The logistic regression model achieved a prediction rate of 79.4 % with a sensitivity of 74.5 % and specificity of 83.2 %.

CONCLUSION

The heart of growth restricted infants is characterized by a more globular right ventricle, shorter ventricle length and smaller thorax diameter. These parameters could improve prediction of FGR and SGA.

Reference Ranges and Development Patterns of Fetal Myocardial Function Using Speckle Tracking Echocardiography in Healthy Fetuses at 17 to 24 Weeks of Gestation

OBJECTIVE

The purposes of the study were to develop reference ranges and maturation patterns of fetal cardiac function parameters measured by speckle tracking echocardiography (STE) using multiple biometric variables at 17 to 24 weeks' gestation among Thai fetuses and to compare with other previous reports.

STUDY DESIGN

The four-chamber view of the fetal heart in 79 healthy fetuses was suitably analyzed by STE to establish the best-fit regression model. The 95% reference intervals and Z-score equations of fetal cardiac function parameters were computed.

RESULTS

The fractional area change of both ventricles, left ventricular (LV) end-diastolic and end-systolic volumes, LV stroke volume, LV cardiac output (CO), and LV CO per kilogram were all increased according to gestational age (GA) and five fetal biometric measurements. However, the global longitudinal strain, basal-apical length fractional shortening (BAL-FS), BAL annular free wall and septal wall FS, BAL free wall and septal wall annular plane systolic excursions, 24-segment transverse width FS, as well as LV ejection fraction were all independent of GA or other somatic characteristics. There were varying development patterns between fetal right and left ventricles of these cardiac function indices across the gestation period.

CONCLUSION

Our study created Z-score and corresponding centile calculators, 5th and 95th centile reference tables, and corresponding graphs and determined the normal evolution across gestation using multiple somatic growth and age variables between 17 and 24 gestational weeks. These nomograms serve as an essential prerequisite for quantitatively evaluating fetal cardiac contractility and allow for precisely detecting early changes in the fetal heart function.

KEY POINTS

· Most fetal cardiac function measurements were correlated with all the independent variables.. · Fetal ventricular function parameters have their own characteristic maturation changes.. · Racial variability may not occupy an important place for fetal myocardial function during these GA..

Evaluation of the changes in cardiac morphology of fetuses with congenital heart disease using fetalHQ

Objective: To evaluate the changes in cardiac morphology of fetuses with congenital heart disease (CHD) using the fetal heart quantitative technique (fetalHQ).Methods: A total of 20 normal pregnant women (control group) and 20 pregnant women suspected of fetal CHD (case group) were included in this study. The dynamic images of the four-chamber view of the fetal heart were recorded and analyzed using fetalHQ. The global sphericity index (GSI) and 24-segment SI of the two groups were compared. The differences in the left and right ventricular 24-segment SI for each group were investigated.Results: There was no statistically significant difference in the GSI between the two groups (p > 0.05). The difference in the SI values of left ventricular segments 1-2 between the case group and control group was statistically significant (all p < 0.05), while the intergroup difference in SI of left ventricular segments 3-24 was not significant (all p > 0.05). The SI of the 24 segments of the right ventricle showed no significant intergroup difference (all p > 0.05). The difference in the left and right ventricular 24-segment SI in the case group did not reach statistical significance (all p > 0.05). In the control group, the SI values between the left and right ventricles were significantly different in segments 18-24 (all p < 0.05), and no significant difference was found in segments 1-17 (all p > 0.05). There was a statistically significant intergroup difference in the percentage of unusual left ventricular SI, determined based on Z-score (p < 0.05), and the percentage of outliers for the right ventricle between the two groups showed no significant difference (p > 0.05).Conclusion: The fetalHQ is regarded as a straightforward and reliable approach for assessing the cardiac GSI and 24-segment SI of left and right ventricles in fetuses diagnosed with CHD. While CHD may not significantly impact the overall shape of the fetal heart or the geometric shape of the right ventricle, in this study, a notable increase in SI values for the left ventricular 1-2 segments was observed, indicating a more flattened ventricular chamber. Additionally, the morphological distinctions between the left and right ventricles in fetuses with CHD are no longer discernible.

Speckle Tracking Analysis in Fetuses with D-Transposition: Predicting the Need for Urgent Neonatal Balloon Atrial Septostomy

INTRODUCTION

Speckle tracking analysis of the endocardium of the right (RV) and left (LV) ventricles was used to evaluate the size, shape, and contractility of these chambers in fetuses with D-Transposition of the great arteries (D-TGA) to identify fetuses that would require emergent balloon atrial septostomy (BAS) after birth.

METHODS

This was a retrospective analysis of fetuses with D-TGA and intact ventricular septum that were divided into 2 groups. Group 1 underwent urgent BAS after birth because of a restrictive atrial septum and group 2 did not. Using speckle tracking analysis, the end-diastolic and end-systolic RV and LV areas, lengths, widths, sphericity indices, and contractility were computed. Logistic regression analysis was performed to identify fetuses who would require urgent neonatal BAS.

RESULTS

Of the 39 fetuses with D-TGA, 55% (n = 22) required urgent neonatal BAS (group 1) and 45% (n = 17) (group 2) did not. When comparing D-TGA groups 1 and 2, differences were seen in RV and LV area, sphericity index for segment 1 of the LV, LV fractional area of change and free wall annular plane systolic excursion, fractional shortening for LV segment 12, and RV free wall strain. Regression analysis of these measurements identified 91% of neonates who underwent BAS, with a false-positive rate of 12%.

CONCLUSION

Using speckle tracking analysis to evaluate the RV and LV, measurable differences were identified for the RV and LV size, shape, and contractility between fetuses who underwent neonatal urgent BAS vs. those who did not require this procedure.

Evaluation of changes of cardiac morphology and function in fetuses with ductus arteriosus constriction by Speckle-tracking echocardiography

BACKGROUND

Premature ductus arteriosus constriction (DA Con) can result in right ventricular enlargement, right ventricular hypertrophy, and tricuspid regurgitation.

METHOD

This study retrospectively analyzed 34 singleton fetuses that underwent fetal echocardiography with a diagnosis of DA Con (16 cases with mild to moderate, and 18 cases with moderate to severe) and 45 healthy fetuses. The morphology and function parameters of cardiac, as well as the 24-Segment of ventricles, were compared between the DA Con group and controls, and between the mild to moderate and moderate to severe groups, using the fetal heart quantification (FHQ) technology.

RESULTS

There were no significant difference in left ventricular parameters in DA Con group when compared to controls. Moreover, fetal 4CV-GSI was significantly reduced, as well as the sphericity index (SI), fractional shortening (FS), global longitudinal strain (GS) and fractional area change (FAC) of right ventricle, especially in the basal-middle segments. Compared with the mild to moderate group, LV-FS increased and RV-FS decreased in moderate to severe group.

CONCLUSION

The results showed that the fetal heart in the DA Con group was different from the controls in morphology and function. FHQ technology provides a comprehensive assessment for the evaluation of cardiac morphological and functional changes in DA Con 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.

Fetal echocardiographic evaluation before and after nifedipine treatment in preterm labor

OBJECTIVE

To assess the effect of nifedipine used for tocolysis on cardiac morphology and functions.

METHODS

The study included 47 pregnant women diagnosed with preterm labor at 32-33 weeks. Fetal echocardiographic evaluation was performed with two-dimensional (2D) imaging, M-mode, pulsed wave (PW) Doppler, and tissue Doppler imaging (TDI) before and after the 48^th hour of nifedipine treatment.

RESULTS

No significant change was observed in Doppler parameters (pulsatility indices of the umbilical artery, middle cerebral artery, ductus venosus) and cardiac morphology (cardiothoracic ratio, end-diastolic longitudinal diameters, sphericity indices, wall thickness) after nifedipine treatment. The parameters obtained with TDI (e', a', s', e'/a', E/e' of mitral and tricuspid valves), M- mode (TAPSE, MAPSE), pulsed Doppler (myocardial performance index, left cardiac output, right cardiac output, tricuspid E, A waves, tricuspid E/A ratio, mitral E, A waves, mitral E/A ratio) did not change after nifedipine treatment.

CONCLUSION

To date, this is the first study to examine the effects of nifedipine on the fetal heart using the TDI. Since nifedipine is a drug that is frequently used and well-tolerated in the prevention of preterm labor, it is crucial that it does not cause changes in fetal cardiac parameters during tocolysis. Therefore, we used TDI in addition to conventional methods to evaluate the effect of nifedipine, which is frequently used in obstetrics, on cardiac functions in the early period. Nifedipine treatment seems not to affect systolic or diastolic functions. This indicates that nifedipine is reliable on cardiac functions and morphology in pregnancies treated for preterm labor.

Post-COVID-19 fetal cardiac evaluation in moderate infection group of pregnant women

PURPOSE

To determine the long-term fetal cardiac effects of the SARS-CoV-2 infection in pregnant women recovered from moderate COVID-19 with fetal echocardiography (ECHO).

METHODS

Forty-five pregnant women that recovered from moderate COVID-19 (CRG) 4 weeks after the infection confirmation, were compared with 45 gestational and maternal age-matched control groups (CG) in terms of demographic features fetal cardiac morphological (sphericity index, cardiothoracic ratio), and functional (myocardial performance index, mitral E/A, tricuspid E/A, mitral and tricuspid annular plane systolic excursion) parameters.

RESULTS

There was no difference in demographic features between the groups. Fetal cardiac morphologic parameters were found to be similar between the two groups. When the fetal cardiac functional assessment of the two groups was compared, only mitral E/A ratio results were found to be statistically significantly lower in the CRG than in the control group (p = 0.030).

CONCLUSION

The fetal heart does not seem to be negatively affected by COVID-19 after recovery from moderate infection. These results about the fetal effect of SARS-CoV-2 may improve our limited knowledge of the utility of fetal ECHO in pregnant women who recovered from COVID-19.

Assessment of the Size and Shape of the 4-Chamber View and the Right and Left Ventricles using Fetal Speckle Tracking in Normal Fetuses at 17-24 Gestational Weeks

INTRODUCTION

The aim of the study was to establish normal reference values obtained by fetal speckle tracking analysis of the fetal heart between 17-24 weeks of gestation among Thai fetuses and compare the nomograms with previous studies.

METHODS

The 4-chamber view of the fetal heart in 79 normal fetuses was analyzed by speckle tracking analysis to determine the best-fit regression model. The 95% reference intervals and Z-score equations of fetal cardiac parameters were computed.

RESULTS

The end-diastolic length, width, area, and circumference of the 4-chamber view (4CV) as well as the ventricular end-diastolic length, 24-segment widths, and area were all increased as a function of gestational age (GA) and 5 fetal biometric parameters. In contrast, the global sphericity index (SI), 24-segment SI, and right ventricle/left ventricle width and area ratios did not change with GA or fetal biometric measurements. There were few differences in Z-score reference ranges of fetal cardiac measurements between the current study and previous studies conducted in different patient populations.

CONCLUSION

Our study provided z-score and corresponding centile calculators, 5th and 95th centile reference tables, and corresponding graphs for evaluating the size and shape of the 4CV and the right and left ventricles using 6 independent variables between 17 and 24 weeks of gestation. These results provide normal reference ranges for future studies of fetuses with pathologies that may alter the size and shape of the 4-chamber view and ventricles.

Cardiac Measurements of Size and Shape in Fetuses With Absent or Reversed End-Diastolic Velocity of the Umbilical Artery and Perinatal Survival and Severe Growth Restriction Before 34 Weeks' Gestation

OBJECTIVES

The purpose of this study was to evaluate the end-diastolic size and shape of the 4-chamber view as well as the right ventricle (RV) and left ventricle (LV) in growth-restricted fetuses before 34 weeks' gestation with absent or reversed end-diastolic velocity of the umbilical artery and compare the results between those with perinatal deaths and those who survived the neonatal period.

METHODS

Forty-nine fetuses with growth restriction and absent or reversed end-diastolic velocity of the umbilical artery were studied. The size, shape, and sphericity index of the 4-chamber view, RV, and LV were assessed. The number and percentage of fetuses with z score values of less than -1.65 and greater than 1.65 were computed.

RESULTS

Of the 49 fetuses, there were 13 perinatal deaths (27%) and 36 (63%) neonatal survivors. Measurements that were unique for neonatal survivors were an increased RV apical transverse width and decreased measurements of the following: LV and RV widths, LV and RV areas, as well as RV sphericity indices.

CONCLUSIONS

Fetuses with a smaller RV and LV size and area and those with a globular-shaped RV were at significantly lower risk for perinatal death.

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.

Evaluation of 24-segment sphericity index of fetal heart using FetalHQ

OBJECTIVE

To evaluate the 24-segment sphericity index (SI) of the fetal heart using FetalHQ regarding the change with advancing gestation and reproducibility.

METHODS

Eighty-one pregnant women at 18-21 + 6 and 28-31 + 6 weeks were studied using FetalHQ to calculate 24-segment SI of left and right ventricles. Intra- and inter-class correlation coefficients and intra- and inter-observer agreements of measurements for SI were assessed in each segment.

RESULTS

With respect to intra-observer reproducibility, all SI values showed correlations between 0.596 and 0.774 for the left ventricle, and between 0.491 and 0.764 for the right ventricle, with good intra-observer agreements except for right ventricular segment 11-15. With respect to inter-observer reproducibility, all SI values showed correlations between 0.473 and 0.755 for the left ventricle, and between 0.48 and 0.767 for the right ventricular segment 1-18. However, right ventricular segment 19-24 showed no correlations. Good inter-observer agreements were noted in the right ventricle, whereas poor inter-observer agreements were evident in the left ventricle. There were significant differences in the mean SI values in the apical segment of the left ventricle between 18-21 + 6 and 28-31 + 6 weeks (p < .05), whereas there were no significant differences in the mean SI values in the right ventricle between both gestational ages.

CONCLUSION

These results show that measurements of 24-segment SI of fetal heart had relatively low reliability of measurements performed by experienced sonographers. This may suggest that more training on proper placement of the 3 end-systolic and end-diastolic reference points during the initial analysis may be relevant.

Differences in cardiac geometry in relation to body size among neonates with abnormal prenatal growth and body size at birth

OBJECTIVES

Both excessive and restricted fetal growth are associated with changes in cardiac geometry and function at birth. There are significant issues when indexing cardiac parameters for body size in the neonatal period. The aims of this study were to determine to what extent cardiac geometry is dependent on body size in term and preterm neonates with restricted or excessive fetal growth and how this is affected by adiposity.

METHODS

This was a cross-sectional study of neonates born between 31 and 42 weeks of gestation, divided into three groups: (1) small-for-gestational age (SGA, birth weight > 2 SD below the mean); (2) large-for-gestational age (LGA, birth weight > 2 SD above the mean); and (3) appropriate-for-gestational-age controls (AGA, birth weight ≤ 2 SD from the mean). Cardiac geometry and function were compared between the study groups, adjusting for body size. The potential impact of infant adiposity and maternal disease was assessed.

RESULTS

In total, 174 neonates were included, of which 39 were SGA, 45 were LGA and 90 were AGA. Body size was reflected in cardiac dimensions, with differences in cardiac dimensions disappearing between the SGA and AGA groups when indexed for body surface area (BSA) or thoracic circumference. The same was true for the differences in atrial and ventricular areas between the LGA and AGA groups. However, left ventricular inflow and outflow tract dimensions did not follow this trend as, when indexed for BSA, they were associated negatively with adiposity, resulting in diminished dimensions in LGA compared with AGA and SGA neonates. Adiposity was associated positively with left ventricular mass, right ventricular length and area and right atrial area. The SGA group showed increased right ventricular fractional area change, possibly reflecting differences in the systolic function of the right ventricle. We found evidence of altered diastolic function between the groups, with the mitral valve inflow E- to lateral E'-wave peak velocity ratio being increased in the LGA group and decreased in the SGA group.

CONCLUSIONS

Cardiac geometry is explained by body size in both term and preterm AGA and SGA infants. However, the nature of the relationship between body size and cardiac dimensions may be influenced by adiposity in LGA infants, leading to underestimation of left ventricular inflow and outflow tract dimensions when adjusted for BSA. Adjustments for thoracic circumference provide similar results to those for BSA. Copyright © 2020 ISUOG. Published by John Wiley & Sons Ltd.

Effects of nifedipine on fetal cardiac function in preterm labor

Objectives To evaluate the effects of nifedipine treatment on fetal hemodynamics and cardiac function during preterm labor. This prospective study assessed several quantitative parameters of fetal cardiac circulation and function, and found no significant changes at 48 h after nifedipine treatment. These findings suggest that tocolytic nifedipine may be safe for fetuses. It supports clinicians to use nifedipine treatment for tocolysis without any cardiac effect on the fetus. Methods A prospective cohort study was conducted at a tertiary hospital between January 2016 and October 2017. A total of 45 pregnant women who required nifedipine for preterm labor were included in this study. Fetal Doppler ultrasound was performed and fetal systolic and diastolic function was measured prior to, and 48 h after, the first nifedipine treatment. Conventional Doppler parameters were used to evaluate fetal heart function and hemodynamic changes. Tricuspid annular plane systolic excursion, mitral annular plane systolic excursion and the sphericity index were also evaluated to assess changes in fetal cardiac morphology. Results No significant changes in fetal Doppler parameters were observed following nifedipine tocolysis. There was no significant difference in the fetal cardiac function parameters of both ventricles before vs. after nifedipine treatment. Tricuspid annular plane systolic excursion, mitral annular plane systolic excursion, and sphericity index values were unchanged following nifedipine treatment. Conclusions Oral administration of nifedipine did not to alter fetal cardiac function or morphology. Fetal cardiac parameters and various Doppler indices were unchanged following nifedipine treatment. Maternal nifedipine treatment does not appear to have any significant effect on fetal cardiac function.

Right ventricular dysfunction identified by abnormal strain values precedes evident growth restriction in small for gestational age fetuses

OBJECTIVES

Small for gestational age (SGA) fetuses have an increased risk for adverse outcome. Placental insufficiency leads to changes in the circulation, with secondary adaptation of the fetal heart resulting in changed cardiac deformation. This deformation can be measured with 2D speckle tracking echocardiography (2D-STE). SGA is antenatally often undiagnosed. The measurement of deformation changes in the fetal heart might help in the prediction of SGA and identify fetuses in need of more intensive surveillance.

METHODS

In this longitudinal prospective cohort study, global longitudinal strain (GLS) and strain rate (GLSR), measured before 23 weeks gestational age were compared between SGA and appropriate for gestational age (AGA) fetuses, based on birthweight corrected for gestational age at birth.

RESULTS

The fetal heart rate was significantly increased in SGA; 158 beats per minute (146-163) vs 148 (134-156); P = 0.035 in AGA. Right ventricle GLS (RV-GLS) values were significantly increased in SGA; -15.87% (-11.69% to -20.55%) vs -20.24% (-16.29% to -24.28%); p = 0.024, respectively.

CONCLUSION

RV-GLS values, measured with 2D-STE, were significantly increased in SGA, indicating systolic RV dysfunction before 23 weeks gestational age in fetuses who will become SGA later in pregnancy. A large longitudinal prospective cohort study is needed to confirm these findings.

Advances in fetal echocardiography: myocardial deformation analysis, cardiac MRI and three-dimensional printing

PURPOSE OF REVIEW

Advances in ultrasound technology have led to new ways of evaluating cardiac function and structure, including myocardial deformation imaging (strain and strain rate), cardiac MRI and three-dimensional (3D) printing. As ultrasound technology has improved, it has become possible to use these modalities to evaluate the fetal heart. This article will review some of the more recent developments in applying these techniques to the evaluation of fetal cardiac structure and function.

RECENT FINDINGS

Myocardial deformation analyses have led to the establishment of normative values for strain and strain rate in the fetal heart and have also been used to evaluate fetal heart function in both fetal disease states and maternal disease states. Technological advances in MRI technology, 3D imaging and 3D printing have opened up new methods of evaluating fetal structural heart disease.

SUMMARY

A deeper understanding of the subtleties of myocardial dysfunction in various fetal and maternal disease states may elucidate the pathophysiology involved and lead to new treatment and/or counseling paradigms that may ultimately affect outcome. Similarly, the ability to image the fetal heart in new ways, including fetal MRI and 3D printing, could potentially change fetal counseling techniques and prenatal planning.

Assessment of ventricular contractility in fetuses with an estimated fetal weight less than the tenth centile

OBJECTIVE

To determine whether abnormal global, transverse, and longitudinal ventricular contractility of the heart in fetuses with an estimated fetal weight <10th centile is present, irrespective of Doppler studies of the umbilical artery and cerebroplacental ratio.

STUDY DESIGN

This was a retrospective study of 50 fetuses with an estimated fetal weight <10th centile that were classified based on Doppler results from the pulsatility indices of the umbilical artery and middle cerebral artery, and the calculated cerebroplacental ratio (pulsatility indices of the umbilical artery/middle cerebral artery). Right and left ventricular measurements were categorized into 3 groups: (1) global ventricular contractility (fractional area change), (2) transverse ventricular contractility (24-segment transverse fractional shortening), and (3) basal-apical longitudinal contractility (longitudinal strain, longitudinal displacement fractional shortening, and basal lateral and septal wall annular plane systolic excursion). Z scores for the above measurements were computed for fetuses with an estimated fetal weight <10th centile using the mean and standard deviation derived from normal controls. Ventricular contractility measurements were considered abnormal if their Z score values were <5th centile (z score <-1.65) or >95th centile (Z score >1.65), depending on the specific ventricular measurement.

RESULTS

The average gestational age at the time of the examination was 32 weeks 4 days (standard deviation 3 weeks 4 days). None of the 50 study fetuses demonstrated absent or reverse flow of the umbilical artery Doppler waveform. Eighty-eight percent (44/50) of fetuses had one or more abnormal measurements of cardiac contractility of 1 or both ventricles. Analysis of right ventricular contractility demonstrated 78% (39/50) to have 1 or more abnormal measurements, which were grouped as follows: global contractility 38% (19/50), transverse contractility 66% (33/50); and longitudinal contractility 48% (24/50). Analysis of left ventricular contractility demonstrated 1 or more abnormal measurements in 58% (29/50) that were grouped as follows: global contractility 38% (19/50); transverse contractility 40% (20/50); and longitudinal contractility 40% (20/50). Of the 50 study fetuses, 25 had normal pulsatility index of the umbilical artery and cerebroplacental ratios, 80% of whom had 1 or more abnormalities of right ventricular contractility and 56% of whom had 1 or more abnormalities of left ventricular contractility. Abnormal ventricular contractility for these fetuses was present in all 3 groups of measurements; global, transverse, and longitudinal. Those with an isolated abnormal pulsatility index of the umbilical artery (n=11) had abnormalities of transverse contractility of the right ventricular and global contractility in the left ventricle. When an isolated cerebroplacental ratio abnormality was present, the right ventricle demonstrated abnormal global, transverse, and longitudinal contractility, with the left ventricle only demonstrating abnormalities in transverse contractility. When both the pulsatility index of the umbilical artery and cerebroplacental ratio were abnormal (3/50), transverse and longitudinal contractility measurements were abnormal for both ventricles, as well as abnormal global contractility of the left ventricle.

CONCLUSIONS

High rates of abnormal ventricular contractility were present in fetuses with an estimated fetal weight <10th centile, irrespective of the Doppler findings of the pulsatility index of the umbilical artery, and/or cerebroplacental ratio. Abnormalities of ventricular contractility were more prevalent in transverse measurements than global or longitudinal measurements. Abnormal transverse contractility was more common in the right than the left ventricle. Fetuses with estimated fetal weight less than the 10th centile may be considered to undergo assessment of ventricular contractility, even when Doppler measurements of the pulsatility index of the umbilical artery, and cerebroplacental ratio are normal.

Aortic Coarctation: A Comprehensive Analysis of Shape, Size, and Contractility of the Fetal Heart

BACKGROUND

An integrated assessment of the size and shape of the 4-chamber view (4-CV) and right and left ventricles (RV and LV) as well as the function of the RV and LV in fetuses with coarctation of the aorta (CoA) has not yet been conducted.

OBJECTIVES

We evaluated the size and shape of the 4-CV, RV, and LV, and function of the RV and LV, to identify a profile for fetuses with CoA when compared to a control population.

METHODS

50 CoA fetuses were compared to 200 controls. This was a retrospective case series comparing the 4-CV of CoA fetuses and controls. The 4-CV end-diastolic area, length, width, and sphericity index were measured to determine the configuration of the 4-CV. Speckle-tracking analysis was used to compute the RV and LV end-diastolic area, length, 24-segment sphericity index, 24-segment transverse width, and the following functional parameters: (1) fractional area change; (2) global, lateral, and septal strain; (3) basal-apical, lateral, and septal annular displacement and fractional shortening; and (4) 24-segment transverse width fractional shortening. Using 5 and 95% reference intervals, the CoA fetal measurements were classified; from these, the odds ratio was computed between the fetuses with CoA and the controls. p < 0.05 was considered significant.

RESULTS

In fetuses with CoA, the 4-CV was spherical in shape, increased in area and width, and decreased in length. Abnormal CoA sphericity indices reflected a flatter LV and a more spherical RV. The LV area, length, and width, and RV length were decreased. The transverse width of the RV was increased. RV and LV global, longitudinal, and transverse contractility were depressed.

CONCLUSIONS

The results demonstrate previously unappreciated differences in the shape, size, and function of the heart in fetuses with CoA. These differences may assist examiners in identifying fetuses with CoA.

Growth of Cardiovascular Structures from the Fetus to the Young Adult

The size, hemodynamics, and function of cardiovascular structures change dramatically from the early fetal life to late adolescence. The principal determinants of cardiovascular dimensions are related to the blood flow needed to meet metabolic demands. This demand is in turn tightly related to body size and body composition, keeping in mind that various tissues may have different metabolic rates. There is no simple model that links cardiac dimensions with a single body size measurement. Consequently, despite abundant scientific literature, few studies have proposed pediatric reference values that efficiently and completely account for the effect of body size. Other factors influence cardiovascular size and function in children, including sex. The influence of sex is multifactorial and not fully understood, but differences in body size and body composition play an important role. We will first review the determinants of cardiovascular size and function in children. We then explore the evaluation and normalization of cardiovascular size and function in pediatric cardiology in relation to the growth of cardiovascular structures during childhood, with a particular focus on sex differences.