Perinatal Changes in Fetal Ventricular Geometry, Myocardial Performance, and Cardiac Function in Normal Term Pregnancies

Impact of maternal bariatric surgery on offspring perinatal cardiac function: A prospective study

OBJECTIVE

To assess perinatal cardiac function in offspring of women with previous bariatric surgery and examine its association with maternal glucose control.

DESIGN

Prospective study.

SETTING

Maternity unit, UK.

POPULATION

Fifty-four fetuses/neonates; 29 of post-bariatric surgery women and 25 of women without surgery.

METHODS

Prospective, longitudinal observational study of pregnant women with and without previous bariatric surgery, matched for early pregnancy body mass index. Cardiac function of all offspring was assessed by two-dimensional conventional, spectral tissue Doppler and speckle-tracking echocardiography at 35-37 weeks of gestation and at 5-7 weeks of age. Maternal glycated haemoglobin (HbA1c) was measured at 27-30 weeks of gestation. Maternal demographics and fetal/infant cardiac function indices were compared between the groups. Correlation coefficient (r) is reported.

MAIN OUTCOME MEASURES

Fetal/infant cardiac function indices.

RESULTS

Compared with no-bariatric neonates, offspring of post-bariatric women were smaller at birth (birthweight centiles: 64.96 ± 36.41 versus 40.17 ± 27.99; p = 0.007). There were no significant differences in fetal/infant cardiac function indices and perinatal cardiac changes, between groups. There was a positive correlation between maternal HbA1c and fetal left ventricular (LV) longitudinal strain (r = 0.33) and LV longitudinal strain rate (r = 0.29), suggesting an inverse relation between HbA1c and fetal LV systolic function, but this was mainly seen in offspring of women with no previous bariatric surgery (r = 0.56 and r = 0.50, respectively).

CONCLUSIONS

Maternal bariatric surgery does not appear to inadvertently affect the offspring cardiac performance. We found an inverse correlation between maternal HbA1c levels and fetal LV systolic function but this was mainly seen in the no-bariatric pregnancies.

Do Maternal Heart Diseases Affect Fetal Cardiac Functions?

OBJECTIVES

To investigate whether fetal cardiac function is affected by underlying heart disease in pregnant women.

METHODS

A total of 100 pregnant women who were ≥34 gestational weeks were included in the study, 40 in the maternal heart disease (MHD) group diagnosed with heart disease and 60 in the control group. All cardiac diseases in pregnant women were diagnosed preconceptionally and categorized according to the New York Heart Association (NYHA) classification system. Fetal cardiac functions of study groups were evaluated by M-mode, color tissue Doppler imaging (c-TDI), and pulsed wave Doppler.

RESULTS

Tricuspid annular plane systolic excursion and myocardial performance index (MPI) values were significantly higher and isovolumetric relaxation time was prolonged in the MHD group. The MPI value was found higher in MHD group with NYHA Class II compared to those with NYHA Class I. No significant change in any of the fetal tricuspid annular peak velocity values measured by c-TDI in the MHD group. There were no differences in fetal cardiac functions and perinatal outcomes between pregnant women with acquired and congenital heart diseases. Patients in NYHA Class II had lower birth weight, 1st and 5th minute APGAR scores, and higher neonatal intensive care unit admission rates.

CONCLUSIONS

Underlying heart diseases in pregnant women can cause alterations in the systolic and diastolic function of the fetal heart. High fetal MPI values detected in cardiac patients may indicate that cardiac pathologies during pregnancy affect fetal cardiac globular myocardial function. Cardiac pathologies that progress with restricted physical activity may cause changes in fetal cardiac function and may be associated with adverse perinatal outcomes.

Left atrial strain in fetal echocardiography - could it be introduced to everyday clinical practice?

OBJECTIVES

Prenatal cardiology is a part of preventive cardiology based on fetal echocardiography and fetal interventional cardiology, which facilitates treatment of congenital heart defects (CHD) in pediatric patients and consequently in adults. Timely prenatal detection of CHD plays a pivotal role in facilitating the appropriate referral of pregnant women to facilities equipped to provide thorough perinatal care within the framework of a well-structured healthcare system. The aim of this paper is to highlight the role of left atrial strain (LAS) in prenatal evaluation of fetal heart and prediction of structural and functional disorders.

METHODS

We conducted a comprehensive literature review searching PubMed for articles published from inception up until August 2023, including the search terms "left atrial strain", "fetal echocardiography", and "prenatal cardiology" combined through Boolean operators. In addition, references lists of identified articles were further reviewed for inclusion.

RESULTS

Our review underscores the significance of LAS parameters in fetal echocardiography as a screening tool during specific gestational windows (starting from 11 to 14 weeks of gestation, followed by better visualization between 18 and 22 weeks of gestation). The left atrial strain technique and its parameters serve as valuable indicators, not only for identifying cardiac complications but also for predicting and guiding therapeutic interventions in cases of both cardiac and noncardiac pregnancy complications in fetuses. Evidence suggests establishment of second-trimester reference strain and strain rate values by speckle-tracking echocardiography in the healthy fetal cohort is essential for the evaluation of myocardial pathologies during pregnancy.

CONCLUSIONS

Finding of LAS of fetal heart is feasible and probably can have potential for clinical and prognostic implications.

The influence of maternal inflammatory bowel diseases on fetal cardiac functions: A case-control study

BACKGROUND

The altered maternal inflammatory milieu and changes in maternal vascular structure (arterial stiffness) and function may affect the fetal heart in pregnant women diagnosed with inflammatory bowel disease (IBD).

AIMS

To investigate fetal cardiac functions in IBD pregnancies and to reveal the relationship between IBD duration and fetal cardiac functions.

STUDY DESIGN

Prospective case-control study.

SUBJECTS

The case group included 19 pregnant women with ulcerative colitis and seven with Crohn's disease who were in remission at the time of the study. The control group consisted of 52 healthy pregnant women matched for gestational age in the third trimester of pregnancy (at 32 to 33 weeks).

OUTCOME MEASURES

Fetal cardiac functions. The assessment was blinded as to whether the patients were cases or controls.

RESULTS

The right ventricular E', E'/A', S', and tricuspid annular plane systolic excursion (TAPSE) were significantly lower, and E/E', myocardial performance index (MPI'), and isovolumetric relaxation time (IVRT') were significantly higher in fetuses of IBD pregnancies. Diastolic functions (E/E', E', E'/A', and IVRT'), systolic functions (S' and TAPSE), and global function (MPI') were changed in the case group. A significantly strong correlation was between maternal disease duration and fetal right ventricle diastolic function parameters (E/E', E, E', E'/A') in the case group (r2 = 0.780; p ≤0.001, r2 = 0.570; p ≤0.001, r2 = 0.604; p ≤0.001, r2 = 0.638; p ≤0.001, respectively).

CONCLUSION

Diastolic and systolic fetal cardiac functions changed in IBD pregnancies. As the disease duration increases, especially fetal cardiac diastolic functions may be affected.

Effect of oval foramen restriction and premature contraction of the arterial catheter on right heart function of fetuses and infants

Objective

The effect of fetal oval foramen restriction and premature contraction of the arterial catheter for the right heart function of fetuses and infants was studied by evaluating the right and left ventricular (RV/LV) ratios, the tricuspid annular plane systolic excursion (TAPSE) value, and the Tei index of right heart function parameters.

Methods

This study was approved by the Ethics Committee of First Affiliated Hospital of Hebei North University (K20190116). We collected 257 fetuses between March 2020 and December 2021. Among these, 98 fetuses that did not have any heart abnormalities were assigned to group A, 91 fetuses with restriction of the left and right atrial channels were assigned to group B, and 68 fetuses with premature contraction of the arterial catheter were assigned to group C. The ventricular transverse diameter, the right heart TAPSE value and the Tei index of fetuses in late pregnancy and 90 days after birth were measured in the three groups, and the diagnostic value of each index for the right heart function injury was evaluated. P < 0.05 indicates significant.

Results

The P-value of the TAPSE value and Tei index of infants in BC and AC groups and postnatal infants were less than 0.05, which was significant. In the BC group, the RV/LV ratio of fetuses was compared when P > 0.05, which was not significant; however, P < 0.05 after birth was considered significant. For fetuses and postnatal infants in the BC group, the RV/LV ratio was negatively associated with the TAPSE value. However, it was positively associated with the Tei index; Diagnostic test results. To predict impaired right heart function after birth, TAPSE had low diagnostic value, RV/LV and Tei index had high diagnostic value.

Conclusions

Oval foramen restriction and premature contraction of the arterial catheter may affect the right heart function after birth and be related to the degree of the right heart enlargement. Although TAPSE prediction of the fetal and postnatal right heart function is limited, the RV/LV ratio and the Tei index can be used to predict impaired right heart function after birth.

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.

Comparison of cardiac morphology and function in small for gestational age fetuses and fetuses with late-onset fetal growth retardation

OBJECTIVES

To compare cardiac structural and functional findings of fetuses with fetal growth restriction (FGR) and small for gestational age (SGA).

METHODS

In this prospective cohort study, patients were classified into three groups using Delphi procedure according to fetal weight, umbilical, uterine artery Doppler and cerebroplacental ratio. Fetal cardiac ultrasonographic morphology and Doppler examination was performed to all pregnant women at 36 weeks of gestation.

RESULTS

Seventy three patients were included in the study. There were one (6.7%) patient in the control group, 2 (13.3%) in the SGA group and 12 (80%) in the FGR group who needed neonatal intensive care unit (NICU) and NICU requirement was significantly higher in FGR fetuses (p<0.001). Left spherical index was found to be lower only among FGR fetuses (p=0.046). Left ventricular wall thickness was decreased and the right/left ventricular wall ratio was increased in FGR fetuses (p=0.006, p<0.001). Tricuspid/mitral valve ratio and mitral annular plane systolic excursion value was lower in FGR fetuses (p=0.034, p=0.024 respectively). Also, myocardial performance index was remarkably higher in FGR group (p=0.002).

CONCLUSIONS

We detected cardiac morphological changes in cases of both SGA and FGR-more pronounced in the FGR cases. Findings related to morphological changes on the left side in FGR cases were considered secondary to volume increase in FGR cases as an indicator of a brain-protective effect. In the FGR group, both systolic and diastolic dysfunctions were detected in the left heart.

Evaluation of fetal cardiac morphology and functions in pregnant women with familial Mediterranean fever

OBJECTIVE

We aimed to evaluate and compare fetal cardiac morphology and functions of pregnant women with familial Mediterranean fever (FMF) and healthy pregnant women.

METHODS

The study included 34 pregnant women with FMF and 68 healthy pregnant women matched with maternal age, gravidity, parity, gestational age, and pre-pregnancy body mass index (BMI) in 34th-37th gestational weeks. Fetal echocardiographic evaluation was performed with two-dimensional (2D) imaging, M-mode imaging, pulsed wave (PW) Doppler, and tissue Doppler imaging (TDI).

RESULTS

Fetal cardiac morphological measures, including cardiothoracic ratio, cardiac axis angle, right and left ventricular area, sphericity index, and ventricular septal thickness was similar in both groups. Compared with the control group, myocardial performance index (MPI), which indicates global myocardial performance, was significantly higher, and ejection time (ET) was significantly shortened in the FMF group. In addition, which shows the diastolic functional parameters such as, tricuspid E wave, E/A, E/E' ratio, and mitral E wave, E/A, E/E' ratio, were significantly higher; tricuspid A and mitral A waves were significantly lower. We found that mitral and tricuspid annular plane systolic excursion (MAPSE and TAPSE) were significantly lower in those with FMF duration over eight years than those with FMF duration less than 8 years.

CONCLUSION

There is no fetal cardiac morphological change in pregnant women with FMF. However, there may be changes in diastolic function. As the maternal FMF duration increases, systolic functions may also change.

Urgent neonatal balloon atrial septostomy in simple transposition of the great arteries: predictive value of fetal cardiac parameters

OBJECTIVES

To investigate the impact of abnormal perinatal loading conditions on cardiac geometry and function in term fetuses and neonates with transposition of the great arteries with intact interventricular septum (simple TGA), and to explore the predictive value of fetal cardiac parameters for an urgent balloon atrial septostomy (BAS) after birth.

METHODS

This was a prospective longitudinal follow-up study of women delivering at term, including both uncomplicated pregnancies with normal outcome and pregnancies affected by fetal simple TGA. Conventional, spectral-tissue Doppler and speckle-tracking echocardiographic parameters were obtained within 1 week before delivery and within the first few hours after delivery. Neonates with simple TGA that required urgent BAS were assessed after the procedure and before corrective arterial switch surgery. Cardiac parameters were normalized by cardiac cycle length, ventricular end-diastolic length or end-diastolic dimension, as appropriate. Fetal and neonatal cardiac parameters were compared between simple-TGA cases and controls, and perinatal changes in the simple-TGA group were assessed. Receiver-operating-characteristics (ROC)-curve analysis was used to assess the predictive value of fetal cardiac parameters for urgent BAS after birth in the simple-TGA group.

RESULTS

A total of 67 pregnant women delivering at term were included in the study (54 normal pregnancies and 13 with a diagnosis of fetal simple TGA). Compared with normal term fetuses, term fetuses with simple TGA exhibited more globular hypertrophied ventricles, increased biventricular systolic function and diastolic dysfunction (right ventricular (RV) sphericity index (SI), 0.58 vs 0.54; left ventricular (LV)-SI, 0.55 vs 0.49; combined cardiac output (CCO), 483 vs 406 mL/min/kg; LV torsion, 4.3 vs 3.0 deg/cm; RV isovolumetric relaxation time (IVRT'), 127 vs 102 ms; P < 0.01 for all). Compared with normal neonates, neonates with simple TGA demonstrated biventricular hypertrophy, a more spherical right ventricle and altered systolic and diastolic functional parameters (RV-SI, 0.61 vs 0.43; RV myocardial performance index, 0.47 vs 0.34; CCO, 697 vs 486 mL/min/kg; LV-IVRT', 100 vs 79 ms; RV-IVRT', 106 vs 71 ms; P < 0.001 for all). Paired comparison of neonatal and fetal cardiac indices in the simple-TGA group showed persistence of the fetal phenotype, increased biventricular systolic myocardial contractility and CCO, and diastolic dysfunction (RV systolic myocardial velocity (S'), 0.31 vs 0.24 cm/s; LV-S', 0.23 vs 0.18 cm/s; CCO, 697 vs 483 mL/min/kg; LV torsion, 1.1 vs 4.3 deg/cm; P < 0.001 for all). Several fetal cardiac parameters in term fetuses with simple TGA demonstrated high predictive value for an urgent BAS procedure after birth. Our proposed novel fetal cardiac index, LV rotation-to-shortening ratio, as a potential marker of subendocardial dysfunction, for a cut-off value of ≥ 0.23, had an area under the ROC curve (AUC) of 0.94, sensitivity of 100% and specificity of 83%. For RV/LV end-diastolic area ratio ≥ 1.33, pulmonary-valve-to-aortic-valve-dimension ratio ≤ 0.89, RV/LV cardiac output ratio ≥ 1.38 and foramen-ovale-dimension-to-total-interatrial-septal-length ratio ≤ 0.27, AUC was 0.93-0.98, sensitivity was 86% and specificity was 83-100% for all.

CONCLUSIONS

Simple-TGA fetuses exhibited cardiac remodeling at term with more profound alterations in these cardiac parameters after birth, suggestive of adaptation to abnormal loading conditions and possible adaptive responses to hypoxemia. Perinatal adaptation in simple TGA might reflect persistence of the abnormal parallel arrangement of cardiovascular circulation and the presence of widely patent fetal shunts imposing volume load on the neonatal heart. The fetal cardiac parameters that showed high predictive value for urgent BAS after birth might reflect the impact of late-gestation pathophysiology and progressive hypoxemia on fetal cardiac geometry and function in simple TGA. If these findings are validated in larger prospective studies, detailed cardiac assessment of fetuses with simple TGA near term could facilitate improvements in perinatal management and refinement of the timing of postnatal intervention strategies to prevent adverse pregnancy outcomes. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.

Progression of left ventricular diastolic function in the neonate and early childhood from transmitral color M-mode filling analysis

BACKGROUND

We implemented sophisticated color M-mode analysis to assess age-dependent progression of left ventricular (LV) diastolic function.

METHODS

Normal infants were prospectively enrolled for serial echocardiograms at 1 week, 1 month, 6 months, 1 year, and 2 years. From color M-mode scans, propagation velocity (V_P), strength of filling (V_S), and intraventricular pressure difference (IVPD) in 3 segments along apex-to-mitral valve scan line were measured.

RESULTS

Age-wise comparisons of diastolic filling from 121 echocardiograms in 31 infants showed V_P (cm/s), V_S (cm²/s), and E-wave IVPD (mmHg) at 1 week to be 66.2 ± 11.9, 75.3 ± 19.9, and 1.5 ± 0.4, respectively, while V_P, V_S, and E-wave IVPD at 1 month were 80.3 ± 14.4, 101.2 ± 28.3, and 2.42 ± 1.1, respectively. There were significant differences in V_P and segmental IVPD between first week and first month (p < 0.005) and IVPD between the age groups (p < 0.001).

CONCLUSIONS

Comprehensive analysis of transmitral color M-mode data is feasible in infants, enabling calculation of pressure drop between the LV base and apex and strength of propagation from two distinct slopes. Profound changes very early followed by relatively constant filling mechanics in later infancy indicate significant LV maturation occurring during the first month of life.

IMPACT

We implemented sophisticated analytic methods for color M-mode echocardiography in infants to assess age- and dimension-dependent changes in left ventricular diastolic function. Comprehensive characterization of transmitral color M-mode flow was feasible, enabling calculation of pressure drop between left ventricular base and apex and strength of propagation. Left ventricular diastolic filling function has predictable maturational progression, with significant differences in the intraventricular pressure between infants from birth to 2 years. This study forms the basis for future studies to examine alteration of early diastolic filling in congenital heart disease.

Initial fetal to initial postnatal echocardiogram in uncomplicated atrioventricular septal defects: Do significant changes occur?

BACKGROUND

Yield of serial echocardiography in fetuses with atrioventricular septal defects (fAVSD) has not been well defined. The goal of this study was to document if any major changes occurred from initial fetal to initial postnatal echocardiogram in uncomplicated fAVSD.

METHODS

fAVSD were excluded if initial fetal scan documented complex CHD or any concerns. Changes in ventricular function, valvular regurgitation, or diagnosis between first fetal and first postnatal echocardiogram were recorded.

RESULTS

Fifty-seven fAVSD met criteria. Ninety-six fetal echocardiograms were done in 57 patients. Initial fetal scan was performed at 24.3 ± 3.7 weeks of estimated gestational age. All fAVSD had normal function, 38 had no atrioventricular valve regurgitation (AVVR), and 19 had mild AVVR. First postnatal echocardiogram was performed at 6.3 ± 15.3 days. Fifty-six patients had normal function, 1 patient had mild dysfunction, 16 patients had no AVVR, 36 had mild AVVR, and 5 had moderate AVVR. Three patients (5%) had an improvement in AVVR by one degree, 27 patients (47%) had no change in AVVR, 24 patients (42%) had an increase in AVVR by one degree, and 3 patients (5%) had an increase in AVVR by two degrees. There was no major missed anatomical diagnosis from first prenatal to first postnatal echocardiogram.

CONCLUSION

In fAVSD that had no concerns on their initial fetal echocardiogram, the majority of patients had no major changes noted between their initial fetal echocardiogram and their first postnatal echocardiogram. Repeat fetal echocardiograms may not necessarily be needed in this cohort of patients.

Speckle-Tracking Echocardiography for the Assessment of Atrial Function during Fetal Life

INTRODUCTION

Speckle-tracking echocardiography has become a major tool in the evaluation of heart function. Atrial strain has emerged as an important component in the assessment of cardiac function, but there is a paucity of prenatal data. The aim of this study was to describe our initial experience of measurement of atrial strain in fetuses, with respect to both feasibility and the strain patterns observed.

METHODS

Four-chamber Digital Imaging and Communications in Medicine loops were acquired prospectively for deformation imaging. Fifty-three normal fetuses with no morphologic or functional abnormalities were selected for analysis. The three strain components of atrial cycle for both left atrium (LA) and right atrium (RA) were acquired-reservoir (LAres or RAres), conduit, and contraction (LAct or RAct)-and are expressed as a percentage. Ratios of these components were calculated. Simple linear regression was used to analyze how the dependent variables changed according to gestational age and frame rate.

RESULTS

The median gestational age was 30 weeks (range, 23-35), and the frame rate was 74 frames per second (fps; range, 35-121). Left atrial strain was feasible in 48/53 (91%), and right atrial strain in 46/53 (87%) of cases. The onset of LA contraction could be identified on the strain curves in 32 of 48 (67%) cases, and of the RA in 17 of 46 (37%) cases. The values of RAres and RAct were higher compared with those of LAres and LAct (33.9% vs 30.3%, P = .014; and 21.5% vs 16.8%, P = .005), and the contraction:reservoir ratio was also higher for RA (0.63 vs 0.55 for LA, P = .003). Higher values for LAres, LAct, RAres, and RAct were associated with higher frame rate (P = .007, .020, .049, and .012, respectively). The onset of LA contraction was better identified with a higher frame rate (mean 77 vs 59 fps when not seen, P = .007). A higher LA contraction:reservoir ratio was associated with a lower gestational age (P = .042).

CONCLUSION

Measurement of atrial strain is feasible in the fetal heart. The values are influenced by gestational age and frame rate, so it is necessary to account for these variables. Comparison of left versus right atrial strain values contrasts with those observed postnatally. Atrial function merits further study during fetal life, to aid understanding of maturational changes and disease states.

Atrial and Ventricular Deformation Analysis in Normal Fetal Hearts Using Two-Dimensional Speckle Tracking Echocardiography

OBJECTIVE

Two-dimensional speckle tracking echocardiography (2D-STE)-based strain values of the left and the right ventricle have been established; however, less is known about atrial deformation. The aim of our study was to assess both atrial strain and ventricular strain using 2D-STE in a cardiac 4-chamber view and to investigate the effect of possible influencing factors such as gestational age.

METHODS

Fetal echocardiography was performed on a Toshiba Aplio 500 ultrasound system. Based on an apical or basal 4-chamber view of the fetal heart, left and right ventricular longitudinal peak systolic strain (LVLPSS and RVLPSS) as well as left and right atrial longitudinal peak systolic strain (LALPSS and RALPSS) were assessed by 2D-STE.

RESULTS

A total of 101 healthy fetuses were included. The mean gestational age (GA) was 26.0 ± 5.6 weeks. GA was significantly positively correlated (p < 0.05) with LVLPSS and RVLPSS and significantly negatively correlated (p < 0.05) with LALPSS and RALPSS. The mean values for LVLPSS and RVLPSS were -17.44 ± 2.29% and -16.89 ± 1.72%. The mean values for LALPSS and RALPSS were 34.09 ± 4.17% and 35.36 ± 2.90%.

CONCLUSION

Ventricular and atrial deformation analysis in 2D-STE was technically feasible and showed comparable values to current data. For future research on myocardial function (MF) of the fetus, considering GA as an influencing factor for deformation analysis seems to be adequate. Especially, atrial deformation analysis allows the assessment of diastolic myocardial function. Further research needs to clarify the clinical meaning of these myocardial deformation indices in fetuses at risk.

Left ventricular torsional mechanics in term fetuses and neonates

OBJECTIVE

Left ventricular (LV) torsion is an important aspect of cardiac mechanics and is fundamental to normal ventricular function. The myocardial mechanics of the fetal heart and the changes that occur during the transition to the neonatal period have not been explored previously. The aim of this study was to evaluate perinatal changes in LV torsion and its relationship with myocardial function.

METHODS

This was a prospective study of 36 women with an uncomplicated term pregnancy. Fetal and neonatal conventional, spectral tissue Doppler and two-dimensional (2D) speckle tracking echocardiography were performed a few days before and within hours after delivery to measure cardiac indices including LV rotational parameters derived from short-axis views at the base and apex of the heart. Linear regression analysis was used to examine the relationship between LV rotational parameters and cardiac geometric and functional indices in term fetuses and neonates. Perinatal changes in LV rotational parameters were assessed.

RESULTS

There were three patterns of LV twist in term fetuses: those with reversed-apex-type LV twist had the lowest median values of LV torsion (0.1°/cm), with higher values (1.6°/cm) in those with infant-type LV twist and the highest values (4.4°/cm) in those with adult-type LV twist. LV torsion was associated significantly with cardiac geometric and functional indices. Perinatal evaluation revealed a significant increase in LV torsion following delivery in fetuses exhibiting reversed-apex-type LV twist (increase of 2.8°/cm, P = 0.009) and a significant decrease in those with adult-type LV twist (decrease of 3.2°/cm, P = 0.008).

CONCLUSIONS

This study demonstrates the feasibility of 2D speckle tracking imaging for accurate assessment of rotational cardiac parameters in term fetuses. There are unique perinatal patterns of LV twist that demonstrate different values of LV torsion, which was found to correlate with indices of ventricular geometry and myocardial function. Differences in patterns of LV twist may therefore reflect differences in compensatory myocardial adaptation to the physiological environment/loading conditions in late gestation in fetuses and postnatal cardiac adjustment to the acute loading changes that occur at delivery. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Nomograms of Fetal Right Ventricular Fractional Area Change by 2D Echocardiography

OBJECTIVES

Fetal right ventricular (RV) function assessment is challenging due to the RV geometry and limitations of in utero assessment. Postnatally, 2D echocardiographic RV fractional area change (FAC) is used to assess RV global systolic function by calculating the percentage of change in RV area from systole to diastole. Reports on FAC are scarce in prenatal life, and nomograms throughout pregnancy are not available. Our aims were (1) to study prenatal RV FAC feasibility and reproducibility and (2) to construct nomograms for RV FAC and end-diastolic (ED) and end-systolic (ES) RV areas from 18 to 41 weeks of gestation.

METHODS

Prospective cohort study including 602 low-risk singleton pregnancies undergoing a fetal echocardiography from 18 to 41 weeks of gestation. RV ED and ES areas were measured following standard recommendations for ventricular dimensions and establishing strict landmarks to identify the different phases of the cardiac cycle. RV FAC was calculated as: ([ED area - ES area]/ED area) × 100. RV FAC intra- and inter-observer reproducibility was evaluated in 45 fetuses by calculating the intraclass correlation coefficient (ICC). Parametric regressions were tested to model each parameter against gestational age (GA) and estimated fetal weight (EFW).

RESULTS

RV areas and FAC were successfully obtained in ∼99% of fetuses with acceptable reproducibility throughout gestation (RV ED area inter-observer ICC [95% CI] 0.96 [0.93-0.98], RV ES area 0.97 [0.94-0.98], and FAC 0.69 [0.44-0.83]). Nomograms were constructed for RV ED and ES areas and FAC. RV areas showed a quadratic and logarithmic increase with GA and EFW, respectively. In contrast, RV FAC showed a slight quadratic decrease throughout gestation (mean RV FAC ranged from 36% at 18 weeks of gestation [10-90th centiles: 25-47%, respectively] to 29% at 41 weeks [10-90th centiles: 18-40%, respectively]). The best models for RV areas and FAC were a second-degree polynomial.

CONCLUSIONS

RV FAC is a feasible and reproducible parameter to assess RV global systolic function in fetal life. We provide reference ranges adjusted by GA and EFW that can be used as normal references for the assessment of RV function in prenatal conditions.

Perinatal changes in fetal cardiac geometry and function in diabetic pregnancy at term

OBJECTIVE

To evaluate the effect of diabetes in pregnancy on fetal and neonatal cardiac geometry and function around the time of delivery.

METHODS

This was a prospective study of 75 pregnant women delivering at term, comprising 54 normal pregnancies and 21 with a diagnosis of pregestational or gestational diabetes mellitus. Fetal and neonatal conventional and spectral tissue Doppler and two-dimensional speckle-tracking echocardiography were performed a few days before and within hours after delivery. Fetal and neonatal cardiac geometry, global myocardial deformation and performance, diastolic and systolic function and left ventricular (LV) torsion were compared between normal pregnancies and those with diabetes, and perinatal changes within the diabetes group were assessed.

RESULTS

Compared with normal pregnancies, diabetic pregnancies demonstrated significant differences in fetal ventricular geometry, myocardial deformation and cardiac function (right ventricular (RV) sphericity index, 0.56 vs 0.65; LV torsion, 2.1 °/cm vs 5.6 °/cm; LV isovolumetric relaxation time, 101 ms vs 115 ms; and RV isovolumetric contraction time, 107 ms vs 119 ms; P < 0.001 for all). Compared with normal pregnancies, diabetic pregnancies demonstrated significant differences in neonatal cardiac parameters (mean RV sphericity index, 0.43 vs 0.55; mean LV torsion, 1.30 °/cm vs 2.78 °/cm; median LV myocardial performance index (MPI'), 0.39 vs 0.51; median RV-MPI', 0.34 vs 0.40; P < 0.01 for all). Paired comparison between fetal and neonatal cardiac indices in diabetic pregnancies demonstrated that delivery resulted in a significant improvement in some, but not all, cardiac indices (mean RV sphericity index, 0.65 vs 0.55; mean LV torsion, 5.60 °/cm vs 2.78 °/cm; median RV-MPI', 0.51 vs 0.40; P < 0.01 for all).

CONCLUSIONS

Compared with normal term fetuses and neonates, those of diabetic women exhibit cardiac indices indicative of myocardial impairment, reflecting a response to a relatively hyperglycemic intrauterine environment with alteration in fetal loading conditions (LV preload deprivation and increased RV afterload) and adaptation to subsequent acute changes in hemodynamic load at delivery. Elucidating mechanisms that contribute to the alterations in perinatal cardiac function in diabetic pregnancy could help in refining management and developing better therapeutic strategies to reduce the risk of adverse pregnancy outcomes. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Intervendor Discordance of Fetal and Neonatal Myocardial Tissue Doppler and Speckle-Tracking Measurements

BACKGROUND

Fetal and neonatal studies report a wide range of cardiac parameters derived by pulsed-wave Doppler tissue imaging (DTI) and two-dimensional speckle-tracking echocardiographic (STE) imaging. The use of different ultrasound systems and their vendor-specific software compromises the ability to compare echocardiographic findings among various studies. The aim of this study was to evaluate intervendor reproducibility as well as intra- and interobserver repeatability of DTI and STE measurements in normal-term fetuses and neonates.

METHODS

A prospective study was conducted of term fetuses (n = 196) from uncomplicated pregnancies assessed days before the onset of labor and a few hours after birth. Fetal and neonatal DTI and STE parameters were obtained and analyzed using vendor-specific software on three ultrasound systems: Toshiba Aplio MX versus GE Vivid E9 and GE Vivid E9 versus Philips EPIQ. A reproducibility study in fetuses and neonates (n = 118) was performed by systematic scanning with head-to-head comparison.

RESULTS

DTI reproducibility showed moderate to good correlation, with good agreement for fetuses and neonates on Toshiba versus GE (intraclass correlation coefficient [ICC] = 0.4-0.8). Correlation of DTI measurements on GE versus Philips was poor to moderate for fetuses (ICC = 0.1-0.6) and moderate to good for neonates (ICC = 0.5-0.8), with wider limits of agreement. Fetal and neonatal STE parameters revealed very poor correlation (ICC = 0.1-0.3) and agreement among ultrasound vendors. Intra- and interobserver repeatability demonstrated good to excellent correlation of all fetal and neonatal DTI and STE measurements, with good agreement irrespective of the ultrasound platform used.

CONCLUSIONS

These findings demonstrate reliable assessment of fetal and neonatal DTI and STE measurements when performed on the same ultrasound platform, whereas ultrasound machines and software from different vendors give significantly divergent estimates of DTI and STE parameters in fetuses and neonates. These intervendor discrepancies have significant clinical and research implications and should be considered when interpreting and comparing study findings, establishing reference standards, or performing systematic reviews.

Perinatal changes in cardiac geometry and function in growth-restricted fetuses at term

OBJECTIVE

To evaluate the effect of fetal growth restriction (FGR) at term on fetal and neonatal cardiac geometry and function.

METHODS

This was a prospective study of 87 pregnant women delivering at term, comprising 54 normally grown and 33 FGR pregnancies. Fetal and neonatal conventional and spectral tissue Doppler and two-dimensional speckle tracking echocardiography were performed a few days before and within hours after birth. Fetal cardiac geometry, global myocardial deformation and performance and systolic and diastolic function were compared between normal and FGR pregnancies before and after birth.

RESULTS

Compared with normally grown fetuses, FGR fetuses exhibited more globular ventricular geometry and poorer myocardial deformation and cardiac function (left ventricular (LV) sphericity index (SI), 0.54 vs 0.49; right ventricular (RV) SI, 0.60 vs 0.54; LV torsion, 1.2 °/cm vs 3.0 °/cm; LV isovolumetric contraction time normalized by cardiac cycle length, 121 ms vs 104 ms; interventricular septum early diastolic myocardial peak velocity/atrial contraction myocardial diastolic peak velocity ratio, 0.60 vs 0.71; P < 0.01 for all). The poorest perinatal outcomes occurred in FGR fetuses with the most impaired cardiac functional indices. When compared with normally grown neonates, FGR neonates showed persistent alteration in cardiac parameters (LV-SI, 0.53 vs 0.50; RV-SI, 0.54 vs 0.44; LV torsion, 1.1 °/cm vs 1.4 °/cm; LV myocardial performance index (MPI'), 0.52 vs 0.42; P < 0.01 for all). Paired comparison of fetal vs neonatal cardiac indices in FGR demonstrated that birth was associated with a significant improvement in some, but not all, cardiac indices (RV-SI, 0.60 vs 0.54; RV-MPI', 0.49 vs 0.39; P < 0.001 for all).

CONCLUSIONS

Compared with normal pregnancies, FGR fetuses and neonates at term exhibit altered cardiac indices indicative of myocardial impairment that reflect adaptation to placental hypoxemia and alterations in hemodynamic load around the time of birth. Elucidating potential mechanisms that contribute to the alterations in perinatal cardiac adaptation in FGR could improve management and aid the development of better therapeutic strategies to reduce the risk of adverse pregnancy outcome. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Maturational patterns in right ventricular strain mechanics from the fetus to the young infant

AIM

To test the hypothesis that right ventricular (RV) function has age-specific patterns of development, we tracked the evolution of RV strain mechanics by 2D-speckle tracking echocardiography (2DSTE) in healthy subjects from mid-gestation through one year of age.

METHODS

We conducted a prospective longitudinal echocardiography study in 50 healthy subjects at five time periods across gestation (16-20 weeks, 21-25 weeks, 26-30 weeks, 31-35 weeks, and 36-40 weeks) and four time periods following delivery (1 week, 1 month, 6 months, and 1 year of age). We characterized RV function by measuring RV global and free wall longitudinal strain and systolic strain rate, and segmental longitudinal strain at the apical-, mid-, and basal- ventricular levels of the free wall. Possible associations of gestational age, postnatal age, estimated fetal weight, body surface area, gender, and heart rate on strain were investigated.

RESULTS

The magnitudes of RV global and free wall longitudinal strain and global strain rate were decreased throughout gestation (p < 0.05 for all). Following birth, the magnitudes of all measures increased from one week through one year (p < 0.001 for all). RV segmental longitudinal strain maintained a base-to-apex gradient (highest-to-lowest) from mid-gestation through one year (p < 0.001). There was no significant difference in strain patterns based on gender or hear rate.

CONCLUSION

The maturational patterns of RV strain are gestational- and postnatal age- specific. With accepted physiological maturation patterns in healthy subjects, these myocardial deformation parameters can provide a valid basis that allows comparison between health and disease.

Longitudinal Annular Systolic Displacement Compared to Global Strain in Normal Fetal Hearts and Those With Cardiac Abnormalities

OBJECTIVES

The purpose of this study was to compare a new technique that measures the midventricular basal-apical longitudinal diastolic and systolic lengths, computes the longitudinal displacement fractional shortening, and compares it to global strain.

METHODS

Two hundred control fetuses were examined between 20 and 40 weeks' gestation, in whom the longitudinal displacement fractional shortening was computed from end-diastolic and end-systolic lengths measured from the apex to the mid portion of the distance between the level of the basal lateral and septal walls using 2-dimnsional speckle tracking. In addition, global strain was computed using speckle tracking. A correlation analysis was used to compare the longitudinal displacement fractional shortening to global strain. The longitudinal displacement fractional shortening of the right ventricle (RV) and left ventricle (LV) was measured in 10 fetuses with heart abnormalities.

RESULTS

The longitudinal displacement fractional shortening for the RV (mean ± SD, 22.94% ± 4.73%) and LV (21.05% ± 4.21%) was independent of gestational age and other biometric growth parameters, as was global strain (RV, -22.7% ± 4.07%); LV, -22.93% ± 3.52%). The RV longitudinal displacement fractional shortening was greater than that of the LV (P < .024). The correlations between the longitudinal displacement fractional shortening and global strain were 0.95 for the RV and 0.97 for the LV. Comparing the longitudinal displacement fractional shortening and global strain in fetuses with abnormal cardiac findings showed concordant findings in 9 of 10 fetuses.

CONCLUSIONS

The RV and LV longitudinal displacement fractional shortening can be computed from 2-dimensional images of the 4-chamber view and correlated with global strain. The longitudinal displacement fractional shortening was significantly greater for the RV than the LV and was abnormal in fetuses with RV and LV cardiac abnormalities.

Influence of estrous cycle and gestation on cardiovascular system of bitches

The purpose of this study was to evaluate the consequences of the estrous cycle and gestation on the cardiovascular system of bitches evaluated through echocardiographic assessment. Fifteen healthy pregnant bitches aged 2 to 6 years and weighing 8.8 ± 2.5 kg were included in the study. Heart rate and blood pressure were clinically evaluated. M-mode, spectral, and tissue Doppler-echocardiography assessments were performed during the anestrous and estrous stages, every 15 days during pregnancy (15, 30, 45, and 60 days), and 45 days postpartum. The data for evaluated variables were submitted for statistical analysis. Heart rate (P = 0.286) and systolic blood pressure (P = 0.686) were not changed as a result of pregnancy or estrus, while ejection fraction (P = 0.0016) and fractional shortening (P = 0.00004) changed. The variables transmitral flow, isovolumetric relaxation time, aortic and pulmonary flow, and some variables related to myocardium movement obtained via tissue Doppler assessment varied (P < 0.05) among the reproductive periods studied. In conclusion, gestation resulted in changes in echocardiography variables, and consequently, on maternal hemodynamics, with myocardial contractility increasing during pregnancy, resulting in greater systolic efficiency and ventricular compliance.

Fetal Cardiac Function in Maternal Diabetes: A Conventional and Speckle-Tracking Echocardiographic Study

BACKGROUND

Intrauterine exposure to a diabetic environment is associated with adverse fetal myocardial remodeling. The aim of this study was to assess the biventricular systolic and diastolic function of fetuses exposed to maternal diabetes (MD) compared with control subjects, using a comprehensive cardiac functional assessment and exploring the role of speckle-tracking to assess myocardial deformation. The authors hypothesized that fetuses exposed to MD present signs of biventricular dysfunction, which can be detected by deformation analysis.

METHODS

A cross-sectional study was conducted in 129 fetuses with structurally normal hearts, including 76 fetuses of mothers with diabetes and 53 of mothers without diabetes. Maternal baseline characteristics, standard fetoplacental Doppler indices, and conventional echocardiographic and myocardial deformation parameters were prospectively collected at 30 to 33 weeks of gestation.

RESULTS

Fetuses of mothers with diabetes had a significantly thicker interventricular septum compared with control subjects (median, 4.25 mm [interquartile range (IQR), 3.87-4.50 mm] vs 3.67 mm [IQR, 3.40-3.93 mm), P < .001), but no effect modification was demonstrated on myocardial deformation analysis. No significant differences were found in conventional systolic and diastolic functional parameters for the left ventricle and right ventricle, except for lower left ventricular cardiac output in the MD group (median, 320 mL/min [IQR, 269-377 mL/min] vs 365 mL/min [IQR, 311-422 mL/min], P < .05]. Deformation analysis demonstrated a significantly lower early diastolic strain rate (SRe) and late diastolic strain rate (SRa) for both ventricles in the MD group (left ventricle: SRe 1.85 ± 0.72 vs 2.26 ± 0.68 sec^-1, SRa 1.50 ± 0.52 vs 1.78 ± 0.57 sec^-1; right ventricle: SRe 1.57 ± 0.73 vs 1.97 ± 0.73 sec^-1, SRa 2 ± 0.77 vs 1.68 ± 0.79 sec^-1; P < .05), suggesting biventricular diastolic impairment. Additionally, the right ventricle presented a lower global longitudinal strain in the study group (-13.67 ± 4.18% vs -15.52 ± 3.86%, P < .05). Multivariate analysis revealed that maternal age is an independent predictor of left and right ventricular global longitudinal strain (P < .05), with a significant effect only in MD after group stratification.

CONCLUSIONS

Fetuses of mothers with diabetes present signs of biventricular diastolic dysfunction and right ventricular systolic dysfunction by deformation analysis in the third trimester of pregnancy. They may represent a special indication group for functional cardiac assessment, independently of septal hypertrophy. Two-dimensional speckle-tracking could offer an additional benefit over conventional echocardiography to detect subclinical unfavorable changes in myocardial function in this population.