A fetal cardiovascular score to predict infant hypertension and arterial remodeling in intrauterine growth restriction

Umbilical Vein Flows and Cardiac Size, Shape, and Ventricular Contractility in Fetuses With Estimated Weight Less-Than 10th Centile

OBJECTIVES

In a cohort of patients with estimated fetal weights (EFWs) <10th centile, we aimed 1) to compare the prevalence of abnormalities of fetal 4-chamber view (4CV) cardiac size, shape, and ventricular contractility in fetal growth restricted (FGR) and small-for-gestational-age (SGA) fetuses and 2) to compare umbilical vein flow (UVF) measurements to standard Doppler surveillance in predicting abnormalities of cardiac function.

METHODS

Prospective observational cohort study of fetuses with EFW <10th percentile. Measurements of size and shape used were 4CV transverse width, 4CV cardiac area, 4CV global sphericity index, and right-to-left ventricular mid-chamber width ratio. Variables of contractility used were fractional shortening change at the mid-ventricle chamber, global longitudinal strain, fractional area change, and left ventricular cardiac output. The UVF and standard Doppler surveillance including umbilical artery (UA), middle cerebral artery, and cerebroplacental ratio (CPR) were collected. Control data were from previously published studies.

RESULTS

A total of 95 fetuses with EFWs <10th centile were included in the study. The rates of abnormalities of cardiac size and shape and ventricular contractility were all significantly elevated compared with normally grown control fetuses but similar between FGR and SGA fetuses. In a subset of 76 patients with UVF data, evaluation UVF identified more patients with any abnormality of contractility compared with UA (37.9 vs 17.2%, P = .02).

CONCLUSIONS

The addition of UVF doubled the detection rate of ventricular contractility abnormalities. The addition of UVF should be considered in the surveillance of FGR and SGA fetuses to further stratify the severity of hypoxemia and to identify those at greater risk for future cardiovascular dysfunction.

Maternal rest improves growth in small-for-gestational-age fetuses (<10th percentile)

BACKGROUND

Optimal management of fetuses diagnosed as small for gestational age based on an estimated fetal weight of <10th percentile represents a major clinical problem. The standard approach is to increase fetal surveillance with serial biometry and antepartum testing to assess fetal well-being and timing of delivery. Observational studies have indicated that maternal rest in the left lateral position improves maternal cardiac output and uterine blood flow. However, maternal bed rest has not been recommended based on the results of a randomized clinical trial that showed that maternal rest does not improve fetal growth in small-for-gestational-age fetuses. This study was conducted to revisit this question.

OBJECTIVE

This study aimed to determine whether maternal bed rest was associated with an increase in the fetal biometric parameters that reflect growth after the diagnosis of a small-for-gestational-age fetus.

STUDY DESIGN

A retrospective study was conducted on fetuses who were diagnosed as small for gestational age because of an estimated fetal weight of <10th percentile for gestational age. The mothers were asked to rest in the left lateral recumbent position. Fetal biometry was performed 2 weeks after the diagnosis. All fetuses before entry into the study had a previous ultrasound that demonstrated an estimated fetal weight of >10th percentile. To assess the response to bed rest, the change in fetal biometric parameters (estimated fetal weight, head circumference, abdominal circumference, and femur length) after the recommendation of bed rest was computed for 2 periods: (1) before the diagnosis of a weight of <10th percentile vs at the time of diagnosis of a weight of <10th percentile and (2) at the time of diagnosis of a weight of <10th percentile vs 2 weeks after maternal bed rest. For repeated measures, proportions were compared using the McNemar test, and percentile values were compared using the Kruskal-Wallis test. A P value of <.05 was considered significant. To describe changes in the estimated fetal weight without bed rest, 2 control groups in which the mothers were not placed on bed rest after the diagnosis of a small-for-gestational-age fetus were included.

RESULTS

A total of 265 fetuses were observed before and after maternal bed rest. The following were observed in this study: (1) after 2 weeks of maternal rest, 199 of 265 fetuses (75%) had a fetal weight of >10th percentile; (2) the median fetal weight percentile increased from 6.8 (interquartile range, 4.4-8.4) to 18.0 (interquartile range, 9.5-29.5) after 2 weeks of bed rest; (3) similar trends were noted for the head circumference, abdominal circumference, and femur length. In the groups of patients who were not asked to be on bed rest, a reassignment to a weight of >10th percentile at a follow-up examination only occurred in 7 of 37 patients (19%) in the Texas-Michigan group and 13 of 111 patients (12%) in the Colorado group compared with the bed rest group (199/265 [75%]) (P<.001).

CONCLUSION

Patients who were prescribed 2 weeks of bed rest after the diagnosis of a fetal weight of <10th percentile had an increase in weight of >10th percentile in 199 of 265 fetuses (75%). This increase in fetal weight was significantly higher than that in the 2 control groups in which bed rest was not prescribed. This observation suggests that bed rest improves fetal growth in a subset of patients.

Abnormal Shape and Size of the Cardiac Ventricles Are Associated with a Higher Risk of Neonatal Death in Fetuses with Isolated Left Congenital Diaphragmatic Hernia

INTRODUCTION

The objective of this study was to evaluate the association between fetal cardiac deformation analysis (CDA) and cardiac function with severe adverse perinatal outcomes in fetuses with isolated left congenital diaphragmatic hernia (CDH).

METHODS

CDA in each ventricle (contractility, size, and shape), evaluated by speckle tracking and novel FetalHQ software, and markers of cardiac function (E/A ratios, pulmonary and aortic peak systolic velocities, and sigmoid annular valve diameters), were evaluated in fetuses with isolated left CDH. Two evaluations were performed: at referral (CDA and function) and within 3 weeks of delivery (CDA). Severe adverse neonatal outcomes were considered neonatal death (ND) or survival with CDH-associated pulmonary hypertension (CDH-PH). Differences and associations between CDA, cardiac function, and severe adverse outcomes were estimated.

RESULTS

Fifty fetuses were included, and seventeen (34%) had severe adverse neonatal outcomes (11 ND and 6 survivors with CDH-PH). At first evaluation, the prevalence of a small left ventricle was 34% (17/50) with a higher prevalence among neonates presenting severe adverse outcomes (58.8 [10/17] vs. 21.2% [7/33]; p = 0.01; OR, 5.03 [1.4-19.1; p = 0.01]) and among those presenting with neonatal mortality (8/11 [72.7] vs. 9/39 [23.0%]; p = 0.03; OR, 8.9 [1.9-40.7; p = 0.005]). No differences in cardiac function or strain were noted between fetuses with or without severe adverse outcomes. Within 3 weeks of delivery, the prevalence of small left ventricle was higher (19/34; 55.8%) with a more globular shape (reduced transverse/longitudinal ratio). A globular right ventricle was significantly associated with ND or survival with CDH-PH (OR, 14.2 [1.5-138.3]; p = 0.02).

CONCLUSION

Fetuses with isolated CDH at risk of perinatal death or survival with CDH-PH had a higher prevalence of a small left ventricle and abnormal shape of the right ventricle.

Cardiovascular decline in offspring during the perinatal period in an ovine model of fetal growth restriction

Fetal growth restriction (FGR) increases the risk cardiovascular disease (CVD) in adulthood. Placental insufficiency and subsequent chronic fetal hypoxemia are causal factors for FGR, leading to a redistribution of blood flow that prioritizes vital organs. Subclinical signs of cardiovascular dysfunction are evident in growth-restricted neonates; however, the mechanisms programming for CVD in adulthood remain unknown. This study aimed to determine the potential mechanisms underlying structural and functional changes within the heart and essential (carotid) and nonessential (femoral) vascular beds in growth-restricted lambs. Placental insufficiency was surgically induced in ewes at 89 days gestational age (dGA, term = 148dGA). Three age groups were investigated: fetal (126dGA), newborn (24 h after preterm birth), and 4-wk-old lambs. In vivo and histological assessments of cardiovascular indices were undertaken. Resistance femoral artery function was assessed via in vitro wire myography and blockade of key vasoactive pathways including nitric oxide, prostanoids, and endothelium-dependent hyperpolarization. All lambs were normotensive throughout the first 4 wk of life. Overall, the FGR cohort had more globular hearts compared with controls (P = 0.0374). A progressive decline in endothelium-dependent vasodilation was demonstrated in FGR lambs compared with controls. Further investigation revealed that impairment of the prostanoid pathway may drive this reduction in vasodilatory capacity. Clinical indicators of CVD were not observed in our FGR lambs. However, subclinical signs of cardiovascular dysfunction were present in our FGR offspring. This study provides insight into potential mechanisms, such as the prostanoid pathway, that may warrant therapeutic interventions to improve cardiovascular development in growth-restricted newborns.NEW & NOTEWORTHY Our findings provide novel insight into the potential mechanisms that program for cardiovascular dysfunction in growth-restricted neonates as our growth-restricted lambs exhibited a progressive decline in endothelium-dependent vasodilation in the femoral artery between birth and 4 wk of age. Subsequent analyses indicated that this reduction in vasodilatory capacity is likely to be mediated by the prostanoid pathway and prostanoids could be a potential target for therapeutic interventions for fetal growth restriction (FGR).

Cardiometabolic sex differences in adults born small for gestational age

Aim

This study aimed to assess the cardiometabolic sex similarities and differences in adults born small for gestational age.

Methods

This study was an ambispective cohort study from a birth registry in Barcelona, Spain, including 523 adult participants (20-40 years-old) subdivided as born small for gestational age (SGA, if birth weight <10th centile) or adequate fetal growth for gestational age (AGA). Cardiometabolic health was assessed by echocardiography, electrocardiogram, blood pressure measurement, vascular ultrasound, anthropometric measurements, and serum glycemia and lipid profile. Stratified analyses by sex were performed by estimation of adjusted absolute difference (AAD) using inverse probability weighting.

Results

Compared with AGA, the stratified analyses by sex showed a more pronounced reduction in ejection fraction [AAD: female -1.73 (95% CI -3.2 to -0.28) vs. male -1.33 (-3.19 to 0.52)] and increment in heart rate [female 3.04 (0.29-5.8) vs. male 2.25 (-0.82 to 5.31)] in SGA females compared with SGA males. In contrast, a more pronounced reduction in PR interval [female -1.36 (-6.15 to 3.42) vs. male -6.61 (-11.67 to -1.54)] and an increase in systolic blood pressure [female 0.06 (-2.7 to 2.81) vs. male 2.71 (-0.48 to 5.9)] and central-to-peripheral fat ratio [female 0.05 (-0.03 to 0.12) vs. male 0.40 (0.17-0.62)] were mainly observed in SGA male compared with SGA female.

Conclusions

Sex differences were observed in the effect of SGA on cardiometabolic endpoints with female being more prone to cardiac dysfunction and male to electrocardiographic, vascular, and metabolic changes. Future research including sex-stratification data is warranted.

Early-Onset Fetal Growth Restriction Increases Left Ventricular Sphericity in Adolescents Born Very Preterm

Left ventricular shape alterations predict cardiovascular outcomes and have been observed in children born preterm and after fetal growth restriction (FGR). The aim was to investigate whether left ventricular shape is altered in adolescents born very preterm and if FGR has an additive effect. Adolescents born very preterm due to verified early-onset FGR and two control groups with birthweight appropriate for gestational age (AGA), born at similar gestational age and at term, respectively, underwent cardiac MRI. Principal component analysis was applied to find the modes of variation best explaining shape variability for end-diastole, end-systole, and for the combination of both, the latter indicative of function. Seventy adolescents were included (13-16 years; 49% males). Sphericity was increased for preterm FGR versus term AGA for end-diastole (36[0-60] vs - 42[- 82-8]; p = 0.01) and the combined analysis (27[- 23-94] vs - 51[- 119-11]; p = 0.01), as well as for preterm AGA versus term AGA for end-diastole (30[- 56-115] vs - 42[- 82-8]; p = 0.04), for end-systole (57[- 29-89] vs - 30[- 79-34]; p = 0.03), and the combined analysis (44[- 50-145] vs - 51[- 119-11]; p = 0.02). No group differences were observed for left ventricular mass or ejection fraction (all p ≥ 0.33). Sphericity was increased after very preterm birth and exacerbated by early-onset FGR, indicating an additive effect to that of very preterm birth on left ventricular remodeling. Increased sphericity may be a prognostic biomarker of future cardiovascular disease in this cohort that as of yet shows no signs of cardiac dysfunction using standard clinical measurements.

Longitudinal Behavior of Left-Ventricular Strain in Fetal Growth Restriction

Fetal growth restriction (FGR) is associated with an increased risk of adverse outcomes resulting from adaptive cardiovascular changes in conditions of placental insufficiency, leading to cardiac deformation and dysfunction, which can be evaluated with 2D speckle tracking echocardiography (2D-STE). The aim of the present study was to evaluate whether reduced fetal growth is associated with cardiac left-ventricle (LV) dysfunction, using 2D-STE software widely used in postnatal echocardiography. A prospective longitudinal cohort study was performed, and global (GLO) and segmental LV longitudinal strain was measured offline and compared between FGR and appropriate-for-gestational-age (AGA) fetuses throughout gestation. All cases of FGR fetuses were paired 1:2 to AGA fetuses, and linear mixed model analysis was performed to compare behavior differences between groups throughout pregnancy. Our study shows LV fetal longitudinal strain in FGR and AGA fetuses differed upon diagnosis and behaved differently throughout gestation. FGR fetuses had lower LV strain values, both global and segmental, in comparison to AGA, suggesting subclinical cardiac dysfunction. Our study provides more data regarding fetal cardiac function in cases of placental dysfunction, as well as highlights the potential use of 2D-STE in the follow-up of cardiac function in these fetuses.

Cardiac remodeling from the fetus to adulthood

Prenatal cardiac remodeling refers to in utero changes in the fetal heart that occur as a response to an adverse intrauterine environment. In this article, we will review the main mechanisms leading to cardiac remodeling and dysfunction, summarizing and describing the major pathological conditions that have been reported to be related to this in utero plastic adaptive process. We will also recap the current evidence regarding the persistence of fetal cardiac remodeling and dysfunction, both in infancy and later in adult life. Moreover, we will discuss primary, secondary, and tertiary preventive measures and future clinical and research aspects.

Early Life Determinants of Vascular Structure in Fetuses, Infants, Children, and Adolescents: A Systematic Review and Meta-Analysis

OBJECTIVE

To investigate the association between early life exposures during the first 1000 days (conception to age 24 months) and aortic intima-media thickness (aIMT), an early indicator of cardiovascular disease (CVD) risk, in youths.

STUDY DESIGN

The MEDLINE, Embase, Scopus, CINAHL, and Allied and Complementary Medicine databases were searched from inception to July 2021. Eligibility criteria included observational controlled studies in youths aged <20 years with risk factors/exposures during the first 1000 days and aIMT measurements (unadjusted mean ± SD). Outcome data were pooled using a random-effects meta-analysis. Meta-regression was used to investigate confounders.

RESULTS

A total of 8657 articles were identified, of which 34 were included in our meta-analysis. The age of participants ranged from 22.9 weeks gestation in utero to 10.9 years. In the meta-analysis (n = 1220 cases, n = 1997 controls), the following factors were associated with greater aIMT: small for gestational age (SGA) status (14 studies, mean difference, 0.082 mm; 95% CI, 0.051-0.112; P < .001; I² = 97%), intrauterine growth restriction (6 studies; mean difference, 0.198 mm, 95% CI, 0.088-0.309; P < .001; I² = 97%), preeclampsia (2 studies; mean difference, 0.038 mm; 95% CI, 0.024-0.051; P < .001; I² = 38%), and large for gestational age (LGA) status (3 studies; mean difference, 0.089 mm; 95% CI, 0.043-0.0136; P < .001; I² = 93%). In meta-regression, older age (P < .001), higher prevalence of maternal smoking (P = .04), and SGA (P < .001) were associated with greater difference in aIMT in preterm participants compared with controls. Limitations included the high heterogeneity present in most meta-analyses and the scope of our meta-regression.

CONCLUSIONS

Adverse early life exposures are associated with greater aIMT in youths, consistent with an increased risk for CVD later in life. Further research is needed to determine whether intervention and preventive strategies deliver clinical benefits to improve future cardiovascular health.

Cardiovascular Dysfunction in Intrauterine Growth Restriction

PURPOSE OF REVIEW

We highlight important new findings on cardiovascular dysfunction in intrauterine growth restriction.

RECENT FINDINGS

Intrauterine growth restriction (IUGR) is a multifactorial condition which negatively impacts neonatal growth during pregnancy and is associated with health problems during the lifespan. It affects 5-15% of all pregnancies in the USA and Europe with varying percentages in developing countries. Epidemiological studies have reported that IUGR is associated with the pathogenesis of hypertension, activation of the renin-angiotensin system (RAS), disruption in placental-mTORC and TGFβ signaling cascades, and endothelial dysfunction in IUGR fetuses, children, adolescents, and adults resulting in the development of cardiovascular diseases (CVD). Experimental studies are needed to investigate therapeutic measures to treat increased blood pressure (BP) and long-term CVD problems in people affected by IUGR. We outline the mechanisms mediating fetal programming of hypertension in developing CVD. We have reviewed findings from different experimental models focusing on recent studies that demonstrate CVD in IUGR.

Impact of offspring endothelial function from de novo hypertensive disorders during pregnancy: An evidence-based review

De novo hypertensive disorders of pregnancy (HDP) which consist of gestational hypertension and preeclampsia affect maternal and offspring morbidity and mortality, and potentially increase the risk of cardiovascular disease in the offspring. It is well known that de novo HDP causes various maternal complications, including cardiovascular diseases, placental abruption and liver and kidney failure. However, there are studies suggesting that offspring of pregnancies complicated by de novo HDP have an increased risk of long-term cardiovascular disease. The endothelium is an important regulator of vascular function, and its dysfunction is highly associated with the development of cardiovascular diseases. Hence, this review aimed to systematically identify articles related to the effect of de novo HDP on the endothelial function of the offspring. A computerized database search was conducted on PubMed, Scopus, and Medline from 1976 until 2022. A total of 685 articles were obtained. We identified another three additional articles through review articles and Google Scholar. Altogether, we used 13 articles for data extraction. All studies reported that endothelial function was impaired in the offspring of de novo HDP. This is most likely attributed to impaired vasodilation, subclinical atherosclerosis formation, inflammation, and dysregulated epigenetic regulation of endothelial functions.

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.

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

AIM

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

MATERIAL AND METHODS

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

RESULTS

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

CONCLUSION

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

4D imaging of fetal right ventricle-feasibility study and a review of the literature

Functional analysis of the fetal cardiovascular system is crucial for the assessment of fetal condition. Evaluation of the right ventricle with standard 2D echocardiography is challenging due to its complex geometry and irregular muscle fibers arrangement. Software package TOMTEC 4D RV-Function is an analysis tool which allows assessment of right ventricular function based on volumetric measurements and myocardial deformation. The aim of this study was to determine the feasibility of this method in fetal echocardiography. The retrospective study was conducted in the high-flow Referral Center for Fetal Cardiology. We recorded 4D echocardiographic sequences of 46 fetuses with normal hearts. Following parameters were calculated: end-diastolic volume (EDV), end-systolic volume (ESV), stroke volume (SV) and ejection fraction (EF), right ventricle longitudinal free-wall (RVLS free-wall) and septal strain (RVLS septum). Tei index was calculated as a standard measure or RV function for comparison. 4D assessment was feasible in 38 out of 46 fetuses (83%). RV volumetric parameters—EDV, ESV and SV—increased exponentially with gestational age. Functional parameters—RV Tei index, EF and strains—were independent of gestational age. Mean EF was 45.2% (± 6%), RV free-wall strain was − 21.2% and RV septal strain was − 21.5%. There was a statistically significant correlation between septal and free-wall strains (r = 0.51, p = 0.001) as well as between EF and RV free-wall strain (r = − 0.41, p = 0.011). 4D RV assessment is feasible in most fetuses. Its clinical application should be further investigated in larger prospective studies.

The thrifty phenotype hypothesis: The association between ultrasound and Doppler studies in fetal growth restriction and the development of adult disease

Barker pioneered the idea that the epidemic of coronary heart disease in Western countries in the 20th century, which paradoxically coincided with improved standards of living and nutrition, has its origin in fetal life. Indeed, there is substantial evidence associating low birthweight because of fetal growth restriction with an increased risk of vascular disease in later adult life. These conclusions led to the second part of the Barker hypothesis, the thrifty phenotype, in which adaptation to undernutrition in fetal life leads to permanent metabolic and endocrine changes. Such changes are beneficial if the undernutrition persists after birth but may predispose the individual to obesity and impaired glucose tolerance if conditions improve. The hypothesis assumes that a poor nutrient supply during a critical period of in utero life may "program" a permanent structural or functional change in the fetus, thereby altering the distribution of cell types, gene expression, or both. The fetus, in response to placental undernutrition and to maintain sufficient vascular supply to the brain, decreases resistance to blood flow in the middle cerebral artery. Simultaneously, because of the limited blood supply to the fetus, the arterial redistribution process is accompanied by increased resistance to flow to other fetal vital organs, such as the heart, kidneys, liver, and pancreas. It may explain why individuals exposed to ischemic changes in utero develop dyslipidemia, lower nephron number, and impaired glucose tolerance, all factors contributing to metabolic syndrome later in life. Nevertheless, support for the hypotheses comes mainly from studies in rodents and retrospective epidemiologic studies. This review focused on ultrasound and Doppler studies of human fetal growth restriction in several fetal organs: the placenta, fetal circulation, brain, heart, kidneys, adrenal glands, liver, and pancreas. Support for the hypothesis was provided by animal studies involving conditions that create fetuses with growth restriction with effects on various fetal organs and by human studies that correlate impaired fetal circulation with the in utero development and function of fetal organs.

Reference ranges for fetal cardiac, ventricular and atrial relative size, sphericity, ventricular dominance, wall asymmetry and relative wall thickness from 18 to 41 gestational weeks

OBJECTIVE

To construct nomograms for fetal cardiac, ventricular and atrial relative size and geometry parameters from 18 to 41 weeks' gestation using a low-risk population of singleton pregnancies.

METHODS

This was a prospective cohort study of 602 low-risk singleton pregnancies undergoing comprehensive fetal echocardiography, from 18 to 41 weeks of gestation, to assess fetal cardiac, atrial and ventricular relative size and sphericity, ventricular dominance, wall asymmetry and relative wall thickness. Intra- and interobserver measurement reproducibility was evaluated using intraclass correlation coefficients (ICC). In order to construct reference ranges across pregnancy, parametric regressions were tested to model each measurement against gestational age and estimated fetal weight. The measurements evaluated were: cardiothoracic ratio; atrial-to-heart area ratios; ventricular-to-heart area ratios; cardiac, ventricular and atrial sphericity indices; right-to-left basal and midventricular ratios; septal-to-free wall thickness ratios; and relative wall thickness.

RESULTS

Fetal cardiac, ventricular and atrial morphometry for assessing relative size and geometry could be successfully performed in > 95% of the population, with moderate-to-excellent interobserver reproducibility (ICC, 0.623-0.907) and good-to-excellent intraobserver reproducibility (ICC, 0.787-0.938). Cardiothoracic ratio and ventricular right-to-left ratio showed a modest increase throughout gestation. Atrial-to-heart and ventricular-to-heart area ratios, atrial sphericity indices and septal-to-free wall thickness ratios were constant with gestational age. Left and right ventricular basal sphericity indices showed a tendency to decrease at the end of gestation, while left and right midventricular sphericity indices tended to decrease in the second trimester. The cardiac sphericity index and left and right relative wall thickness showed a modest decrease with gestational age. Nomograms across gestation were constructed for all echocardiographic parameters described.

CONCLUSIONS

The assessment of cardiac, ventricular and atrial relative size and geometry is feasible and reproducible in the fetus. We provide standardized reference ranges for these parameters throughout gestation, enabling the accurate assessment of cardiac remodeling patterns during fetal life. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.

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 intrauterine growth status on aortic intima-media thickness and aortic diameter in near-term fetuses: a comparative cross-sectional study

Intrauterine undernutrition may lead to fetal vascular programming. We compared abdominal aortic intima-media thickness (aIMT) and aortic diameter (aD) between appropriate for gestational age (AGA) and growth-restricted fetuses (GRF). We recruited 136 singleton fetuses at 34-37 weeks of gestation from Fetal Medicine Unit of Aga Khan University Hospital, Karachi (January-November 2017). Subjects were classified as AGA (n = 102) and GRF (n = 34) using INTER-GROWTH 21st growth reference and standard ultrasound protocol. Their far- and near-wall aIMT and aD were compared after adjustment of maternal age, first-trimester body mass index, fetal gender, hypertension and hyperglycemia in pregnancy. As the severity of growth restriction increased in GRF, aIMT and aD showed an increasing and a decreasing trend, respectively. Both far- and near-wall aIMT in GRF [(adj. β = 0.082, 95% confidence interval [CI] 0.042-0.123) and (adj. β = 0.049, 95% CI 0.010-0.089)] were significantly greater with reference to AGA fetuses. GRF subgroup analysis into small for gestational age (SGA) fetuses and intrauterine growth restricted (IUGR) revealed highly significant difference between AGA and IUGR for far (0.142 mm, P-value < 0.001) and near-wall aIMT (0.115 mm, P-value < 0.001) and marginally significant aD difference (0.51 mm, P-value 0.05). These findings suggest that the extent of fetal aortic remodelling is influenced by the severity of growth restriction. Hence, the targeted interventions for the cardiovascular health promotion of IUGR and SGA born neonates are desirable during early childhood, particularly in set ups with high prevalence of low birth weight babies.

Postnatal persistence of cardiac remodeling and dysfunction in late fetal growth restriction

Fetal growth restriction is one of the most common obstetric complications, affecting 7-10% of all pregnancies. Affected fetuses are exposed to an adverse environment in utero during a critical time of development and may face long-term health consequences such as increased cardiovascular risk in adulthood. Growth restricted fetuses develop remodeled hearts with signs of systolic and diastolic dysfunction. Cardiac adaptations are more evident in early severe cases, but also present in late onset fetal growth restriction. Cardiovascular remodeling persists into postnatal life, from the neonatal period to adolescence, encompassing an increased susceptibility to adult disease. In this review, we summarize the current evidence on cardiovascular programming associated to fetal growth restriction, its postnatal consequences and potential strategies to reduce their cardiovascular risk.

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.

Maternal Predictors of Disparate Outcomes in Children With Single Ventricle Congenital Heart Disease

Background Significant variability in morbidity and mortality persists for children with functionally single ventricle congenital heart disease (SV-CHD) despite standardization in medical and surgical care. We hypothesized that maternal health factors may be associated with an increased risk of poor outcomes in children with SV-CHD. Methods and Results This retrospective, observational, cohort study included term maternal-infant pairs with a diagnosis of SV-CHD who underwent surgical palliation from 2006 to 2015 at Primary Children's Hospital. Pairs lacking maternal variables of interest or infant follow-up data were excluded. The association of maternal risk factors of abnormal pre-pregnancy body mass index, abnormal gestational weight gain (<7 or >20 kg), hypertensive disorders, and gestational diabetes mellitus with death/transplant and hemodynamics were analyzed using regression models. Of 190 infants, 135 (71%) maternal-infant dyads had complete data for inclusion. Death or transplant occurred in 48 infants (36%) during an average follow-up of 2.2 years (0.1-11.7 years). Abnormal gestational weight gain was associated with an increased risk of death and/or transplant in logistic regression (odds ratio, 3.22; 95% CI, 1.32-7.86; P=0.01), but not Cox regression (hazard ratio, 1.9; 95% CI, 1.0-3.7; P=0.055). Mean pulmonary artery pressures were higher in the setting of abnormal gestational weight gain (16.5±2.9 versus 14.7±3.0 mm Hg; P<0.001), and abnormal pre-pregnancy body mass index (15.7±3.5 versus 14.2±2.1 mm Hg; P<0.001) in the systemic right ventricle group. Conclusions Abnormal gestational weight gain (excessive or inadequate) is a novel risk factor for worse outcomes in SV-CHD. The fetoplacental environment may alter the trajectory of vascular development to impact outcomes in infants with SV-CHD.

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.

Size and shape of the four-chamber view of the fetal heart in fetuses with an estimated fetal weight less than the tenth centile

BACKGROUND

Fetuses with an estimated fetal weight below the 10^th centile have an increased risk of adverse perinatal and long-term outcomes as well as increased rates of cardiac dysfunction, which often alters cardiac size and shape of the 4-chamber view and the individual ventricles. As a result, a simple method has emerged to screen for potential cardiac dysfunction in fetuses with estimated fetal weights <10^th centile by measuring the size and shape of the 4-chamber view and the size of the ventricles.

OBJECTIVE

To determine the number of fetuses with an abnormal size and shape of the 4-chamber view and size of the ventricles in fetuses with an estimated fetal weight <10^th centile.

MATERIALS AND METHODS

This was a retrospective study of 50 fetuses between 25 and 37 weeks of gestation with an estimated fetal weight <10^th centile. Data from their last examination were analyzed. From an end-diastolic image of the 4-chamber view, the largest basal-apical length and transverse width were measured from their corresponding epicardial borders. This allowed the 4-chamber view area and global sphericity index (4-chamber view length/4-chamber view width) to be computed. In addition, tracing along the endocardial borders with speckle tracking software enabled measurements of the right and left ventricular chamber areas and the right ventricle/left ventricle area ratios to be computed. Doppler waveform pulsatility indices from the umbilical (umbilical artery pulsatility index) and middle cerebral arteries (middle cerebral artery pulsatility index) were analyzed, and the cerebroplacental ratio (middle cerebral artery pulsatility index/umbilical artery pulsatility index) computed. Umbilical artery pulsatility indices >90^th and cerebroplacental ratios <10^th centile were considered abnormal. Using data from the control fetuses, the centile for each of the cardiac measurements was categorized by whether it was <10^th or >90^th centile, depending upon the measurement.

RESULTS

Of the 50 fetuses with estimated fetal weight <10^th centile, 50% (n = 25) had a normal umbilical artery pulsatility index and cerebroplacental ratio. These fetuses had significantly more (P < 0.02 to <0.0001) abnormalities of the size and shape of the 4-chamber view than controls. In all, 44% had a 4-chamber view area >90^th centile, 32% had a 4-chamber view global sphericity index <10^th centile, 56% had a 4-chamber view width >90^th centile, and 80% had 1 or more abnormalities of size and/or shape. The remaining 50% of fetuses (n = 25) had abnormalities of 1 or both for the umbilical artery pulsatility index and/or cerebroplacental ratio. These fetuses had significantly higher rates of abnormalities (P <0.05 to <0.0001) than controls for the following 4-chamber view measurements: 36% had a 4-chamber view area >90^th centile; 28% had a 4-chamber view global sphericity index <10^th centile; and 68% had a 4-chamber view width >90^th centile. Only those fetuses with an abnormal umbilical artery pulsatility index had significant changes in ventricular size; 56% had a left ventricular area <10^th centile; 28% had a right ventricular area <10^th centile; 36% had right ventricular/left ventricular area ratio >90^th centile. One or more of the above abnormal measurements were present in 92% of the fetuses.

CONCLUSION

Higher rates of abnormalities of cardiac size and shape of the 4-chamber view were found in fetuses with an estimated fetal weight <10^th centile, regardless of their umbilical artery pulsatility index and cerebroplacental ratio measurements. Those with a normal umbilical artery pulsatility index and an abnormal cerebroplacental ratio had larger and wider measurements of the 4-chamber view. In addition, the shape of the 4-chamber view was more globular or round than in controls. These fetuses may have an increased risk of perinatal complications and childhood and/or adult cardiovascular disease. Screening tools derived from the 4-chamber view, acting as surrogates for ventricular dysfunction, may identify fetuses who could benefit from further comprehensive testing and future preventive interventions.

Hemodynamic factors associated with fetal cardiac remodeling in late fetal growth restriction: a prospective study

Background Altered cardiac geometry affects a proportion of fetuses with growth restriction (FGR). The aim of this study was to explore the hemodynamic factors associated with cardiac remodeling in late FGR. Methods This was a prospective study of singleton pregnancies complicated by late-onset FGR undergoing assessment of left (LV) and right (RV) ventricular sphericity-index (SI). The study population was divided in two groups according to the presence of cardiac remodelling, defined as LVSI <5th centile. The following outcomes were explored: gestational age at birth, birthweight, caesarean section (CS) for fetal distress, umbilical artery (UA) pH and neonatal admission to special care unit. The differences between the 2 groups in UA pulsatility index (PI), middle cerebral artery (MCA) PI, uterine artery PI, cerebroplacental ratio (CPR) and umbilical vein (UV) flow corrected for fetal abdominal circumference (UVBF/AC) were tested. Results In total, 212 pregnancies with late FGR were enrolled in the study. An abnormal LV SI was detected in 119 fetuses (56.1%). Late FGR fetuses with cardiac remodeling had a lower birthweight (2390 g vs. 2490; P = 0.04) and umbilical artery pH (7.21 vs. 7.24; P = 0.04) and were more likely to have emergency CS (42.8% vs. 26.9%; P = 0.023) and admission to special care unit (13.4% vs. 4.3%; P = 0.03) compared to those with normal LVSI. No difference in either UA PI (p = 0.904), MCA PI (P = 0.575), CPR (P = 0.607) and mean uterine artery PI (P = 0.756) were present between fetuses with or without an abnormal LV SI. Conversely, UVBF/AC z-score was lower (-1.84 vs. -0.99; P ≤ 0.001) in fetuses with cardiac remodeling and correlated with LV (P ≤ 0.01) and RV SI (P ≤ 0.02). Conclusion Fetal cardiac remodelling occurs in a significant proportion of pregnancies complicated by late FGR and is affected by a high burden of short-term perinatal compromise. The occurrence of LV SI is independent from fetal arterial Dopplers while it is positively associated with umbilical vein blood flow.

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

Aim

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

Methods

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

Results

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

Conclusion

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

Proportionality at birth and left ventricular hypertrophy in healthy adolescents

BACKGROUND

Perinatal growth has important implications for cardiac development. Low birth weight is associated with cardiovascular (CV) events and mortality, and animal studies have shown that fetal growth restriction is associated with cardiac remodeling in the perinatal period leading to a permanent loss of cardiomyocyte endowment and compensatory hypertrophy.

AIMS

To determine associations of birthweight (BW) and multiple proportionality indexes (body mass index (BMI); weight/length² and Ponderal index (PI); weight/length³) at birth on one hand, with left ventricular (LV) structure and function during adolescence.

SUBJECTS

379 healthy adolescents aged 14-18 years in Augusta, Georgia.

OUTCOME MEASURES

LV structure and function parameters, including intraventricular septal thickness in diastole (IVSd), LV internal dimension in diastole (LVIDd), LV internal diameter in systole (LVIDs), LV posterior wall thickness in diastole (LVPWd), relative wall thickness (RWT), midwall fractional shortening (MFS), and ejection fraction, were assessed by echocardiography.

RESULTS

When associations of birthweight, birth BMI, and birth PI with LV structure and function parameters were separately evaluated with linear regression adjusting for age, sex, race, Tanner stage, socioeconomic status, and physical activity, significant positive associations of BW with LVIDd (P = 0.004), birth BMI with LV mass index (P = 0.01), and birth PI with IVSd (P = 0.02), LVPWd (P = 0.03), and LV mass index (P = 0.002) were identified. When LV structure and function parameters were compared across PI tertiles, a significant U-shaped trend for LV mass index (P_quadratic = 0.04) was identified.

CONCLUSIONS

Our adolescent data suggest that proportionality at birth may identify associations between perinatal growth and cardiac remodeling independent of birthweight alone.

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.

Speckle Tracking of the Basal Lateral and Septal Wall Annular Plane Systolic Excursion of the Right and Left Ventricles of the Fetal Heart

OBJECTIVE

Annular plane systolic excursion (APSE) has been evaluated for the right (RV) and left (LV) ventricles using M-mode echocardiography. This study examined APSE using 2-dimensional speckle tracking (2DST) of the lateral and septal annuli of the RV and LV in normal fetuses.

METHODS

Two hundred normal fetuses were prospectively examined between 20 and 40 weeks' gestation, in which the end-diastolic and end-systolic lengths were measured from the apex to the insertion of the annuli into the lateral and septal walls of the RV and LV using 2DST. Subtracting the end-systolic from the end-diastolic length resulted in the APSE measurement. The APSE values from the ventricular and septal locations were regressed against biometric and gestational age independent variables, and the mean and standard deviation computed using fractional polynomial analysis. Within-subject repeated measures of variance were used to compare results within and between the right ventricular and left ventricular basal APSE values.

RESULTS

When regressed against the independent variables the R² for the APSE of the right ventricular lateral wall ranged from 0.39 to 0.40, the left ventricular lateral wall 0.29 to 0.31, the right ventricular septal wall 0.22 to 0.40, and the left ventricular septal wall 0.05 to 0.07. There was a significant difference (P < .001) for APSE between the right ventricular and left ventricular lateral wall and their respective septal annuli, the left ventricular and right ventricular lateral wall annuli, and the left ventricular and right ventricular septal annuli.

CONCLUSIONS

The right ventricular and left ventricular lateral and septal wall APSE can be computed using 2DST and are associated with changing fetal biometric and age measurements.

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

OBJECTIVE

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

METHODS

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

RESULTS

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

CONCLUSION

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

Cardiovascular Programming During and After Diabetic Pregnancy: Role of Placental Dysfunction and IUGR

Intrauterine growth restriction (IUGR) is a condition whereby a fetus is unable to achieve its genetically determined potential size. IUGR is a global health challenge due to high mortality and morbidity amongst affected neonates. It is a multifactorial condition caused by maternal, fetal, placental, and genetic confounders. Babies born of diabetic pregnancies are usually large for gestational age but under certain conditions whereby prolonged uncontrolled hyperglycemia leads to placental dysfunction, the outcome of the pregnancy is an intrauterine growth restricted fetus with clinical features of malnutrition. Placental dysfunction leads to undernutrition and hypoxia, which triggers gene modification in the developing fetus due to fetal adaptation to adverse utero environmental conditions. Thus, in utero gene modification results in future cardiovascular programming in postnatal and adult life. Ongoing research aims to broaden our understanding of the molecular mechanisms and pathological pathways involved in fetal programming due to IUGR. There is a need for the development of effective preventive and therapeutic strategies for the management of growth-restricted infants. Information on the mechanisms involved with in utero epigenetic modification leading to development of cardiovascular disease in adult life will increase our understanding and allow the identification of susceptible individuals as well as the design of targeted prevention strategies. This article aims to systematically review the latest molecular mechanisms involved in the pathogenesis of IUGR in cardiovascular programming. Animal models of IUGR that used nutrient restriction and hypoxia to mimic the clinical conditions in humans of reduced flow of nutrients and oxygen to the fetus will be discussed in terms of cardiac remodeling and epigenetic programming of cardiovascular disease. Experimental evidence of long-term fetal programming due to IUGR will also be included.

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

OBJECTIVE

Fetuses with growth restriction have been reported to have an abnormal sphericity index (SI), which is indicative of the shape of the ventricular chambers of the heart. Our aim was to evaluate the SI for 24 transverse segments distributed from base to apex of the right (RV) and left (LV) ventricles to determine whether, in small-for-gestational-age (SGA) fetuses, the SI is abnormal at locations other than the basal segment.

METHODS

We evaluated 30 SGA fetuses between 25 and 37 weeks of gestation. SI was computed for both ventricles by dividing the end-diastolic mid-basal-apical length by each of 24 end-diastolic transverse segmental widths, from base (Segment 1) to apex (Segment 24). For each ventricle, the Z-score and centile for the SI from each of the 24 segments were computed using the mean and SD from published equations. The 24-segment method, defining abnormal SI as values < 10^th centile or > 90^th centile, was compared with that of using only the basal segment by chi-square analysis to determine the number of fetuses identified with an abnormal SI.

RESULTS

In 23 of the 30 (77%) SGA fetuses, at least one of the 24 transverse segments in one or both ventricles had an abnormal SI; in 17% of cases, both ventricles were affected, in 23% of cases only the RV was involved and in 37% of cases only the LV was involved. Compared with the 24-segment model, significantly fewer fetuses with an abnormal SI were identified using only basal Segment 1, from the RV base (58%, 7/12; P < 0.01) or only Segment 12, in the mid portion of the RV (50%, 6/12; P < 0.005). Combining measurements of Segment 1 and Segment 12 from the RV identified 83% of fetuses with at least one abnormal SI and was not significantly different from using the 24-segment model. Similarly, significantly fewer fetuses with an abnormal SI were identified using only LV basal Segment 1 (63%, 10/16; P < 0.006) or only Segment 12, in the mid portion of the LV (75%, 12/16; P < 0.03), when compared with the 24-segment model. Combining measurements of both LV Segment 1 and Segment 12 identified 81% (13/16) of fetuses with an abnormal SI and was not significantly different from using the 24-segment model.

CONCLUSION

The 24-segment SI of RV and LV provides a comprehensive method with which to examine the shape of the ventricular chambers and identifies more SGA fetuses with an abnormal SI than are identified using only the basal segment SI. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Relationship of prelabor fetal cardiac function with intrapartum fetal compromise and neonatal status at term

OBJECTIVES

To investigate prospectively the relationship of fetal cardiac function and Doppler ultrasound parameters with intrapartum fetal compromise (IFC) in appropriately grown term fetuses. Secondary aims were to correlate prenatal cardiac function with neonatal acid-base status, intrapartum fetal heart rate (FHR) abnormalities and adverse neonatal outcomes.

METHODS

This was a blinded, prospective, observational, cohort study of 270 women with an uncomplicated singleton pregnancy who underwent fortnightly ultrasound assessment from 36 weeks' gestation until delivery at the Mater Mother's Hospital, Brisbane, Australia. Fetal cardiac output and blood flow parameters were assessed and correlated with intrapartum and neonatal outcomes. The primary outcome was need for operative (either Cesarean or instrumental vaginal) delivery for IFC. Secondary outcome measures were acidosis at birth, 5-min Apgar score ≤ 7, suspicious or pathological FHR abnormalities and admission to the neonatal intensive care unit.

RESULTS

Two hundred and seventy women were included in the analysis, of whom 51 (18.9%) had an emergency operative delivery for IFC. Fetuses that had emergency delivery for IFC showed lower mean left ventricular cardiac output (LVCO) (560 ± 44 mL/min vs 617 ± 73 mL/min; P < 0.001), lower mean LVCO/right ventricular cardiac output (RVCO) ratio (0.55 ± 0.07 vs 0.64 ± 0.11; P < 0.001), lower mean cerebroplacental ratio (CPR) (1.62 ± 0.3 vs 1.90 ± 0.5; P < 0.001) and higher mean RVCO (1026 ± 105 mL/min vs 978 ± 110 mL/min; P = 0.003) compared with those that did not develop IFC. Additionally, LVCO and CPR were lower in fetuses with adverse neonatal outcome.

CONCLUSION

Term fetuses with estimated fetal weight > 10^th centile that develop IFC have evidence of lower LVCO and higher RVCO, which are in turn associated with poorer condition of the newborn. Fetal CPR is positively correlated with LVCO. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Prelabour myocardial deformation and cardiac output in fetuses that develop intrapartum compromise at term: a prospective observational study

Objective: Redistribution of cardiac output is responsible for the "brain sparing" effect seen during periods of acute or chronic fetal stress. We investigated the relationship between prelabour cardiac function in fetuses that subsequently developed intrapartum fetal compromise (IFC). Methods: A blinded, prospective, observational, cohort study, at Mater Mother's Hospital, Brisbane, Australia. A cohort of 284 women with uncomplicated singleton pregnancies underwent ultrasound every 2 weeks from 36 weeks until delivery. Fetal cardiac output was assessed by conventional Doppler ultrasound and myocardial deformation was measured using velocity vector imaging. Results: Two hundred and seventy three women were included in the final analysis, of which 19% had an emergency operative delivery for intrapartum fetal compromise (IFC). Global left ventricular strain (-12.1%, interquartile ranges (IQR) - 10.3 to -14% versus 13%, IQR -11.3 to -14.2%, p = .01) and strain rate (-1.00, IQR 0.85-1.16 s^-1 versus -1.11, IQR -1.00 to -1.21 s^-1, p < .001) were lower in fetuses that required any emergency operative delivery for IFC compared to those that did not. Global longitudinal right ventricular strain rate was lower in fetuses that developed IFC (-1.04 ± 0.22 s^-1 versus 1.13 ± 0.22 s^-1, p < .001), whereas global right ventricular strain did not show any significance differences between the two groups. Additionally, left ventricular cardiac output was lower in fetuses that developed IFC or had a composite neonatal morbidity (560 ± 44 mL/min versus 617 ± 72 mL/min, p < .001) or (581 ± 44 mL/min versus 612 ± 72 mL/min, p < .01), respectively. Conclusion: Lower global left ventricular strain and strain rate and cardiac output are associated with IFC and poorer condition of the newborn. Assessment of fetal cardiac function may be useful for risk stratification for intrapartum fetal compromise in apparently "low risk" term pregnancies.

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.

24-segment sphericity index: a new technique to evaluate fetal cardiac diastolic shape

OBJECTIVE

Because of parallel circulation in the fetus and the differential effect that various disease states may have on the shape of the right and left ventricles, this study was conducted to evaluate the sphericity index (SI) of 24 transverse segments distributed from the base to the apex of each of the ventricular chambers.

METHODS

Two hundred control fetuses were examined between 20 and 40 weeks of gestation. The displacement of the ventricular endocardium during the cardiac cycle was computed using offline speckle-tracking software. From the ASCII output of the analysis, we analyzed 24 end-diastolic transverse segments, distributed from the base to the apex of each ventricle, as well as the end-diastolic mid-basal-apical length. The SI was computed for each of the 24 segments by dividing the mid-basal-apical length by the transverse length for each segment. Regression analysis was performed against biometric measurements and gestational age according to last menstrual period and ultrasound. Eight fetuses, in which the four-chamber view appeared subjectively to demonstrate chamber disproportion, were evaluated as examples to demonstrate the utility of this technology.

RESULTS

The SI for each segment was independent of gestational age and fetal biometric measurements. The SI of the right ventricle was significantly (P < 0.001) lower than that of the left ventricle for segments 1-18, suggesting that the right ventricle was more globular in shape than was the left ventricle at the base, mid and a portion of the apical segments of the chamber. Fetuses with various cardiac structural abnormalities and abnormal fetal growth had abnormal SI values that reflected either a more globular or a more flattened ventricular chamber.

CONCLUSION

Determination of SI for each of 24 segments of the fetal right and left ventricles provides a comprehensive method to examine the shape of the ventricular chambers. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Physiological adaptation of the growth-restricted fetus

The growth-restricted fetus in utero is exposed to a hostile environment and suffers undernutrition and hypoxia. To cope with the stress, the fetus changes its physiological functions. These adaptive changes aid intrauterine survival; however, they can lead to permanent functional and structural changes that can contribute to the development of serious chronic diseases later in life. Epigenetic mechanisms are an important part of the pathophysiological processes behind this "developmental origin of adult diseases." The dominant cardiovascular adaptive change is the redistribution of blood flow in hypoxic fetuses, with preferential supply of blood to the fetal brain, myocardium, and adrenal glands. The proportion of blood from the umbilical vein to the ductus venosus and foramen ovale increases, which increases the cardiac output of the left heart ventricle. The increased perfusion of fetal brain can be followed with Doppler ultrasound as increased diastolic velocities and decreased pulsatility index in the middle cerebral artery.

Long-term cardiovascular consequences of fetal growth restriction: biology, clinical implications, and opportunities for prevention of adult disease

In the modern world, cardiovascular disease is a leading cause of death for both men and women. Epidemiologic studies consistently have suggested an association between low birthweight and/or fetal growth restriction and increased rate of cardiovascular mortality in adulthood. Furthermore, experimental and clinical studies have demonstrated that sustained nutrient and oxygen restriction that are associated with fetal growth restriction activate adaptive cardiovascular changes that might explain this association. Fetal growth restriction results in metabolic programming that may increase the risk of metabolic syndrome and, consequently, of cardiovascular morbidity in the adult. In addition, fetal growth restriction is strongly associated with fetal cardiac and arterial remodeling and a subclinical state of cardiovascular dysfunction. The cardiovascular effects ocurring in fetal life, includes cardiac morphology changes, subclinical myocardial dysfunction, arterial remodeling, and impaired endothelial function, persist into childhood and adolescence. Importantly, these changes have been described in all clinical presentations of fetal growth restriction, from severe early- to milder late-onset forms. In this review we summarize the current evidence on the cardiovascular effects of fetal growth restriction, from subcellular to organ structure and function as well as from fetal to early postnatal life. Future research needs to elucidate whether and how early life cardiovascular remodeling persists into adulthood and determines the increased cardiovascular mortality rate described in epidemiologic studies.

Clinician performed ultrasound in fetal growth restriction: fetal, neonatal and pediatric aspects

Fetal growth restriction (FGR) affects 7-10% pregnancies. Conventional and tissue Doppler imaging has noted cardiac compromise during fetal and early neonatal periods in this cohort. In this article, we discuss the use of salient ultrasound parameters across age groups. During fetal life, certain feto-placental sonographic parameters have been linked to adverse perinatal outcomes and are predictive of later life hypertension. During the early postnatal period altered morphometry (hypertrophied and globular hearts) with sub-clinical impairment of cardiac function has been noted in both term and preterm infants with FGR. Vascular imaging has noted thickened and stiffer arteries in association with significantly elevated blood pressure. Similar findings in the pediatric age groups indicate persistence of these alterations, and have formed the basis of intervention studies. Assessment methodology and clinical relevance of these parameters, especially in designing and monitoring of intervention strategies is discussed. Frontline care givers (obstetricians and neonatologists) are increasingly using point of care ultrasound to discern these manifestations of FGR during the sub-clinical phase.

Cord Blood Biomarkers of Cardiac Dysfunction and Damage in Term Growth-Restricted Fetuses Classified by Severity Criteria

OBJECTIVE

To assess cardiovascular function and damage in term small-for-gestational-age (SGA) and intrauterine growth-restricted (IUGR) fetuses by echocardiography and biomarkers in cord blood.

METHODS

This was a cohort study including 60 normal fetuses and 47 term small fetuses subclassified as small for gestational age (SGA) with estimated fetal weight (EFW) between the 3rd and 9th centiles and normal fetoplacental Doppler (n = 14) or intrauterine growth restriction (IUGR, n = 33) if EFW <3rd centile or EFW <10th centile together with cerebroplacental ratio <5th and/or mean uterine artery pulsatility index >95th centile. Fetal echocardiography included left myocardial performance index (MPI) and annular plane systolic excursion. Fetal B-type natriuretic peptide (BNP), troponin-I, heart-type fatty acid-binding proteins (H-FABP), and homocysteine concentrations were measured in cord blood collected at delivery.

RESULTS

Both SGA and IUGR cases presented echocardiographic signs of systolic and diastolic dysfunction with increased MPI (mean controls 0.43 [SD 0.12], SGA 0.47 [0.03], and IUGR 0.57 [0.08], p < 0.01) and decreased mitral annular plane systolic excursion (controls 6.0 mm [1.0], SGA 5.5 mm [0.6], and IUGR 4.9 mm [0.8], p = 0 01). IUGR fetuses presented increased levels of cord blood BNP (controls 17.2 pg/mL [11.5], SGA 22.4 pg/mL [10.7], and IUGR 31.2 pg/mL [26.8], p < 0.01). Troponin I was increased in both SGA and IUGR cases (controls 0.004 ng/mL [0.007], SGA 0.012 ng/mL [0.02], and IUGR 0.018 ng/mL [0.05], p < 0.01). H-FABP and homocysteine showed similar values among groups.

CONCLUSIONS

Cardiac dysfunction and cell damage is a common feature of term SGA and IUGR fetuses despite of the severity criteria for perinatal outcome. Further research is needed to evaluate the potential long-term consequences on their cardiovascular system.

Abnormal Fetal Findings Associated With a Global Sphericity Index of the 4-Chamber View Below the 5th Centile

OBJECTIVES

The purpose of this study was to evaluate the global sphericity index (GSI) of the 4-chamber view and correlate the results with abnormal ultrasound findings.

METHODS

The epicardial end-diastolic basal-apical length (BAL) and transverse length (TL) of the 4-chamber view were measured to compute the GSI (BAL/TL) in 200 control fetuses between 20 and 40 weeks' gestation. Three hundred study fetuses were prospectively examined between 17 and 39 weeks' gestation. The GSI, Z score, and centile were computed for each of the fetuses.

RESULTS

The GSI (1.233; SD, 0.0953) in the control fetuses was independent of gestational age. Eighteen percent of the study fetuses (55 of 300) had a GSI below the 5th centile (<1.08), of whom 96% (53 of 55) had additional abnormal ultrasound findings. Fetuses with an estimated fetal weight below the 10th centile had a significantly (P < .05) higher rate of an umbilical artery Doppler pulsatility index above the 95th centile (27% versus 17.7%), a middle cerebral artery Doppler pulsatility index below the 5th centile (27% versus 0%), an abnormal cerebroplacental ratio (27% versus 4.5%), and an amniotic fluid index of less than 5 cm (36% versus 9%). The TL was significantly increased compared with the BAL in fetuses with cardiac dysfunction, irrespective of the estimated fetal weight.

CONCLUSIONS

An abnormal GSI below the 5th centile is associated with abnormal fetal ultrasound findings.

Descriptive analysis of different phenotypes of cardiac remodeling in fetal growth restriction

OBJECTIVE

To identify different cardiac phenotypes among cases of fetal growth restriction (FGR).

METHODS

Echocardiography was performed in 126 cases with FGR (birth weight < 10^th centile) and 64 appropriate-for-gestational-age (AGA) fetuses. Principal component and cluster analyses were performed to identify different cardiac phenotypes among FGR cases.

RESULTS

Three different cardiac phenotypes were identified among the FGR group: globular in 54% of cases, elongated in 29% of cases and hypertrophic in 17% of cases. Those with a globular heart had the lowest median left-ventricular sphericity index (controls, 1.78 (interquartile range (IQR), 1.62-1.97); FGR elongated, 1.92 (IQR, 1.78-2.09); FGR globular, 1.44 (IQR, 1.36-1.52); FGR hypertrophic, 1.65 (IQR, 1.42-1.77); P = 0.001). FGR cases with an elongated left ventricle had nearly normal cardiac dimensions. FGR cases with a hypertrophic phenotype had the highest median left-ventricular wall thickness (controls, 1.22 (IQR, 1.10-1.67) mm/kg; FGR elongated, 1.52 (IQR, 1.28-1.86) mm/kg; FGR globular, 1.65 (IQR, 1.39-1.99) mm/kg; FGR hypertrophic, 3.68 (IQR, 3.45-4.71) mm/kg; P = 0.001) and cardiac dimensions. Globular and elongated phenotypes showed a fetoplacental profile of late-onset FGR, while the hypertrophic phenotype showed signs of early-onset FGR. The hypertrophic group also had the poorest perinatal results, having the lowest birth-weight centile, gestational age at delivery and Apgar score and the highest postnatal blood pressure and aorta intima-media thickness.

CONCLUSIONS

FGR induces at least three different cardiac phenotypes, with early-onset FGR cases being associated with a hypertrophic response and worse perinatal outcomes. This cardiac phenotypic classification may improve identification of FGR cases with the highest perinatal and long-term cardiovascular risks. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

Online versus offline spatiotemporal image correlation (STIC) M-mode for the evaluation of cardiac longitudinal annular displacement in fetal growth restriction

PURPOSE

Our first aim was to compare online M-mode with offline spatiotemporal image correlation (STIC) M-mode for assessing longitudinal annular displacement (LAD) in growth-restricted fetuses (FGR). Our second aim was to compare LAD measures of FGR cases with controls.

MATERIALS AND METHODS

Prospective study including 40 FGR cases (defined estimated fetal weight and birth weight <10th centile) and 72 normally grown fetuses matched to cases by gestational age at scan. LAD was measured with online M-mode and offline STIC M-mode at the left and right ventricular free walls and septum in all fetuses.

RESULTS

FGR cases had a significant decrease in LAD by STIC in all sites as compared to controls (e.g. right LAD in FGR mean 6.7 mm (SD 1.2) versus controls 7.2 mm (1.2), p = .033). There was a non-significant trend for lower values in FGR when using online M-mode (e.g. right LAD in FGR 6.9 mm (1.5) versus controls 7.4 mm (1.5), p = .084).

CONCLUSIONS

STIC M-mode seems a better method than online M-mode for detecting subtle changes in myocardial motion. STIC presents more precise results and allows an ideal placement of the M-mode arrow. These results confirm previous data suggesting decreased longitudinal motion in FGR.

Persistence of Cardiac Remodeling in Preadolescents With Fetal Growth Restriction

BACKGROUND

Fetal growth restriction (FGR) affects 5% to 10% of newborns and is associated with increased cardiovascular mortality in adulthood. We evaluated whether prenatal cardiovascular changes previously demonstrated in FGR persist into preadolescence.

METHODS AND RESULTS

A cohort study of 58 FGR (defined as birth weight below 10th centile) and 94 normally grown fetuses identified in utero and followed-up into preadolescence (8-12 years of age) by echocardiography and 3-dimensional shape computational analysis. Compared with controls, FGR preadolescents had a different cardiac shape, with more spherical and smaller hearts. Left ventricular ejection fraction was similar among groups, whereas FGR had decreased longitudinal motion (decreased mitral annular systolic peak velocities: control median, 0.11 m/s [interquartile range, 0.09-0.12] versus FGR median 0.09 m/s [interquartile range, 0.09-0.10]; P<0.01) and impaired relaxation (isovolumic relaxation time: control, 0.21 ms [interquartile range, 0.12-0.35] versus FGR, 0.35 ms [interquartile range, 0.20-0.46]; P=0.04). Global longitudinal strain was decreased (control mean, -22.4% [SD, 1.37] versus FGR mean, -21.5% [SD, 1.16]; P<0.001) compensated by an increased circumferential strain and with a higher prevalence of postsystolic shortening in FGR as compared with controls. These differences persisted after adjustment for parental ethnicity and smoking, prenatal glucocorticoid administration, preeclampsia, gestational age at delivery, days in intensive care unit, sex, age, and body surface area at evaluation.

CONCLUSIONS

This study provides evidence that cardiac remodeling induced by FGR persists until preadolescence with findings similar to those reported in their prenatal life and childhood. The findings support the hypothesis of primary cardiac programming in FGR for explaining the association between low birth weight and cardiovascular risk in adulthood.

Fetal Growth Restriction Induces Heterogeneous Effects on Vascular Biomechanical and Functional Properties in Guinea Pigs (Cavia porcellus)

Aim: Fetal growth restriction (FGR) is associated with a variety of cardiometabolic diseases in adulthood which could involve remodeling processes of the vascular walls that could start in the fetal period. However, there is no consensus whether this remodeling affects in a similar way the whole vascular system. We aimed to determine the effects of FGR on the vasoactive and biomechanical properties of umbilical and systemic vessels in fetal guinea pigs.

Methods: FGR was induced by implanting ameroid occluders at mid-gestation in uterine arteries of pregnant guinea pigs, whilst the control group was exposed to simulated surgery. At the term of gestation, systemic arteries (aorta, carotid and femoral) and umbilical vessels were isolated to determine ex vivo contractile and biomechanical responses (stretch-stress until rupture) on a wire myograph, as well as opening angle and residual stresses. Histological characteristics in tissue samples were measured by van Gieson staining.

Results: Aorta and femoral arteries from FGR showed an increased in biomechanical markers of stiffness (p < 0.01), contractile capacity (p < 0.05) and relative media thickness (p < 0.01), but a reduced internal diameter (p < 0.001), compared with controls. There were no differences in the biomechanical properties of carotid and umbilical from control and FGR fetuses, but FGR umbilical arteries had a decreased contractile response to KCl (p < 0.05) along with a reduced relative media thickness (p < 0.05).

Conclusion: Altogether, these changes in functional, mechanical and morphological properties suggest that FGR is associated with a heterogeneous pro-constrictive vascular remodeling affecting mainly the lower body fetal arteries. These effects would be set during a pathologic pregnancy in order to sustain the fetal blood redistribution in the FGR and may persist up to adulthood increasing the risk of a cardiovascular disease.

Fetal cardiovascular remodeling persists at 6 months in infants with intrauterine growth restriction

OBJECTIVES

Intrauterine growth restriction is associated with increased cardiovascular risk later in life but the link between fetal disease and postnatal risk is not well-documented. We evaluated longitudinally the association between cardiovascular remodeling in small-for-gestational-age (SGA) fetuses and at 6 months of age.

METHODS

A cohort of 80 SGA fetuses (defined by estimated fetal and birth weights < 10(th) centile) delivered > 34 weeks' gestation was compared with 80 normally grown age-matched control fetuses, with follow-up at 6 months of corrected age (i.e. 6 months from estimated date of delivery according to first-trimester crown-rump length). Cardiovascular evaluation included a comprehensive echocardiographic assessment in both fetuses and infants and blood pressure and aortic intima-media thickness (aIMT) measurement in infants. Parameters were adjusted by linear regression analysis for gender, gestational age at delivery, pre-eclampsia, prenatal glucocorticoid exposure, Cesarean delivery, admission to neonatal intensive care unit and body surface area.

RESULTS

Both pre- and postnatally, when compared with controls, the SGA group showed a more globular cardiac shape (left sphericity index: controls 2.06 vs SGA 1.87 (P = 0.022) prenatally and 1.92 vs 1.67 (P = 0.007) postnatally), as well as signs of systolic longitudinal dysfunction (systolic annular peak velocity (S'): 7.2 vs 6.3 cm/s (P = 0.003) prenatally and 7.9 vs 6.4 cm/s (P < 0.001) postnatally; tricuspid annular plane systolic excursion: 7.2 vs 6.8 mm (P = 0.015) prenatally and 16.0 vs 14.2 mm (P < 0.001) postnatally) and diastolic dysfunction (left isovolumetric relaxation time: 46 vs 52 ms (P < 0.001) prenatally and 50 vs 57 ms (P = 0.034) postnatally). In addition, infants in the SGA group had increased mean blood pressure (mean: 61 vs 70 mmHg, P < 0.001) and maximum aIMT (0.57 vs 0.66 mm; P < 0.001).

CONCLUSIONS

Primary cardiovascular changes are already present in the SGA fetus and persist at 6 months of age. These data support prenatal cardiovascular remodeling as a mechanistic pathway of increased risk later in life in cases of SGA, regardless of Doppler abnormalities. Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd.

Human fetal growth restriction: a cardiovascular journey through to adolescence

Intrauterine growth restriction has been noted to adversely impact morbidity and mortality in the neonatal period as well as cardiovascular well-being in adolescence and adulthood. Recent data based on a wide range of ultrasound parameters during fetal and neonatal life has noted early and persistent involvement of the cardiovascular system. Some of these measures are predictive of long-term morbidities. Assessment of vascular mechanics is a new and novel concept in this population, and opens up avenues for diagnosis, monitoring and evaluation of the likely effectiveness of interventions. Prevention of these adverse vascular and cardiac outcomes secondary to fetal growth restriction may be feasible and of clinical relevance. This review focuses on growth restriction in humans with respect to cardiovascular remodeling and dysfunction during fetal life, persistence of functional cardiac impairment during early childhood and adolescence, and possible preventive strategies.

Intrauterine growth restriction: impact on cardiovascular development and function throughout infancy

Intrauterine growth restriction (IUGR) refers to the situation where a fetus does not grow according to its genetic growth potential. One of the main causes of IUGR is uteroplacental vascular insufficiency. Under these circumstances of chronic oxygen and nutrient deprivation, the growth-restricted fetus often displays typical circulatory changes, which in part represent adaptations to the suboptimal intrauterine environment. These fetal adaptations aim to preserve oxygen and nutrient supply to vital organs such as the brain, the heart, and the adrenals. These prenatal circulatory adaptations are thought to lead to an altered development of the cardiovascular system and "program" the fetus for life long cardiovascular morbidities. In this review, we discuss the alterations to cardiovascular structure, function, and control that have been observed in growth-restricted fetuses, neonates, and infants following uteroplacental vascular insufficiency. We also discuss the current knowledge on early life surveillance and interventions to prevent progression into chronic disease.