Growth patterns and cerebroplacental hemodynamics in fetuses with congenital heart disease

Pregnancy Complications in Fetal Congenital Heart Disease: A Result of Common Early Developmental Pathways Rather Than Fetal Hemodynamics

OBJECTIVE

The aim of this study was to compare placenta-related complications (adverse placental syndrome) between different types of fetal CHD based on cardiac hemodynamics.

METHOD

All CHD cases diagnosed prenatally by fetal ECHO during 2009-2023 were selected. Exclusion criteria were as follows: multiple pregnancies, pregnancy termination, known genetic aberrations, and extracardiac anomalies. Cases were categorized into 6 groups based on theorized hemodynamic factors. Reference values for fetal growth restriction (FGR), preeclampsia (PE), pregnancy induced hypertension (PIH), and intra uterine fetal demise (IUFD) from the overall Dutch and/or European population were used.

RESULTS

After exclusion, 1293 cases were available for analysis. The incidence of FGR was 198/1247 (15.9%). There was a significant difference in FGR between the groups of CHD (p = 0.002) though it could not be correlated with aortic flow and oxygenation. There was a high incidence of PE (64/1282, 5.0%), PIH (43/1284, 3.3%), and IUFD (33/1291, 2.6%) in our cohort as compared to reference values. Nonetheless, there were no differences in PE, PIH, and IUFD between the different CHD groups.

CONCLUSION

A high incidence of adverse placental syndrome was found though this could not be related to fetal hemodynamics. Even in CHDs without hemodynamic changes, a high incidence of these complications was found. This might be a clinical manifestation of early embryological developmental pathways that affect both the placenta and the fetal heart.

Congenital Heart Disease Fetuses Have Decreased Mid-Gestational Placental Flow, Placental Malperfusion Defects, and Impaired Growth

Background

Placental health may impact the development and outcomes of congenital heart disease (CHD). CHD fetuses have been shown retrospectively to have decreased placental blood flow.

Objectives

The purpose of this study was to determine if CHD fetuses with decreased placental blood flow have placental pathology at birth and if there is a relationship between placental blood flow, placental pathology, and outcomes.

Methods

We performed a prospective case-control study of 38 CHD fetuses, including 28 with single ventricle physiology and 36 controls. Demographic, clinical, and postnatal biometric data were collected. Umbilical venous volume flow (UVVF) was measured from 2nd trimester fetal echocardiograms. Placentas underwent standardized pathological analysis. Standard descriptive statistics and regression analyses were performed to analyze the relationship between UVVF, placental defects, and outcomes.

Results

CHD fetuses had a 15% decrease in mid-gestational UVVF indexed to fetal weight (P < 0.01), and a 27% reduction in UVVF as a proportion of fetal cardiac output (P < 0.01) compared to controls. CHD fetuses had increased placental maternal vascular malperfusion (MVM) lesions (44% vs 18%, P < 0.05), especially high-grade MVM (39% vs 9.1%, P = 0.05), and a trend toward increased placental fetal vascular malperfusion lesions (42% vs 23%, P = 0.10). Placental MVM but not fetal vascular malperfusion lesions were associated with decreased birth weight in CHD fetuses (P < 0.001). There was no association between UVVF and placental pathologic findings or fetal growth.

Conclusions

CHD (particularly single ventricle) fetuses have decreased mid-gestational placental blood flow, increased placental malperfusion defects, and impaired fetal growth. Placental MVM may influence impaired fetal growth in CHD.

Recommendations for the training and practice of fetal cardiology from the Association of European Paediatric Cardiology

Prenatal detection of cardiac abnormalities has increased significantly over the past few decades, such that fetal cardiology has developed into a sub-specialty of paediatric and congenital cardiology. As this speciality develops further and extends across Europe and more globally, it is important to standardize the requirements for training and subsequent practice, to optimize prenatal diagnosis and perinatal care. In addition to the knowledge and technical skills required to make a correct diagnosis, the counseling of families after diagnosis and the planning of appropriate perinatal management is equally important. The aim of these recommendations is to provide a framework for both basic and advanced training for paediatric cardiologists wishing to practice as fetal cardiologists, as well as highlighting requisites for a fetal cardiology service. All aspects regarding training in fetal cardiology and service provision are addressed including diagnosis, counseling and management.

Adaptive Growth of the Ductus Arteriosus and Aortic Isthmus in Various Ductus-Dependent Complex Congenital Heart Diseases

BACKGROUND

The ductus arteriosus (DA) is critical in maintaining postnatal circulation in neonates with obstructed systemic circulation (OSC) and pulmonary circulation (OPC). We hypothesized that the size of the DA and aortic isthmus (AoI) undergoes adaptive growth in utero to counteract the hemodynamic challenges in these congenital heart diseases (CHD).

METHODS

Postnatal echocardiograms of neonates diagnosed prenatally with ductal-dependent CHD who were started on prostaglandins within 24 h of birth were reviewed. We assessed the cross-sectional area of the aortic valve opening, pulmonary valve opening, AoI, and DA by calculating (diameter)2/body surface area. Neonates were classified into OSC or OPC then subgrouped depending upon the patency of semilunar valves: OSC with and without aortic atresia (OSC-AA and OSC-nAA, respectively) and OPC with and without pulmonary atresia (OPC-PA and OPC-nPA, respectively).

RESULTS

Ninety-four cases were studied. The DA in OSC was significantly larger than OPC, and the DA in OSC-AA was significantly larger than OSC-nAA. The size of the AoI was significantly larger in OPC than OSC and larger in OSC-AA than OSC-nAA. Within the OSC-nAA group, there was no significant difference in the size of the DA, AoI, or pulmonary valve opening between those with retrograde flow (RF) at the AoI and without (nRF) except the aortic valve opening was significantly larger in nRF. All groups had comparable cross-sectional areas of systemic output.

CONCLUSIONS

Our findings suggest that DA and AoI show compensatory growth to maintain critical blood flow to vital organs against primary anatomical abnormalities in ductus-dependent CHD. (249 words).

Placenta histology related to flow and oxygenation in fetal congenital heart disease

BACKGROUND

Fetuses with congenital heart defects (CHD) show delayed neurodevelopment, fetal growth restriction (FGR) and placenta related complications. The neurodevelopmental delay may be, partly, attributed to placental factors.

AIM

As both placental development and fetal aortic flow/oxygenation influence neurodevelopment, placentas were compared within fetal CHD groups based on aortic oxygenation and flow, aiming to unravel the true effects in the developmental processes.

STUDY DESIGN

Placental tissues of pregnancies with fetal CHD and healthy controls were selected from biobanks of two Dutch academic hospitals (LUMC, UMCU). Additionally, biometry and Dopplers were assessed.

SUBJECTS

CHD cases with reduced oxygenation (RO) towards the fetal brain were compared to cases with reduced flow (RF) in the aortic arch and healthy controls. Genetic abnormalities, termination of pregnancy, fetal demise and/or multiple pregnancies were excluded.

OUTCOME MEASURES

Histological outcomes were related to fetal Dopplers and biometry. A placenta severity score was used to assess the severity of placental abnormalities per case.

RESULTS

In CHD, significantly more delayed maturation, maternal vascular malperfusion, fetal hypoxia and higher placenta severity scores (median 14 in RO, 14 in RF, 5 in controls, p < 0.001) were observed. Doppler abnormalities (PI UA > p90, PI MCA < p10, CPR < p10) and FGR were more often found in CHD. There were no differences in placental abnormalities, fetal growth and fetal Dopplers between cases with RO and RF.

CONCLUSION

Fetal hemodynamics in the ascending aorta could not be related to placenta characteristics. We hypothesize that placental development influences neurodevelopment in excess of hemodynamics in CHD cases.

Post-COVID-19 Fetal Cardiac Morphology and Systolic Evaluation in Infected Pregnant Women by Fetal Heart Quantification Technology

OBJECTIVES

Due to the government's liberalization of epidemic control, the current 2019 novel coronavirus disease (COVID-19) has started to spread widely within China. This study aimed to use the fetal heart quantification (fetal HQ) technique to assess the cardiac function and morphology of the fetuses of pregnant women diagnosed with COVID-19 in the early stages of pregnancy.

METHODS

Exactly 86 pregnant women diagnosed with COVID-19 infection in early pregnancy (COVID-19 group) and 90 healthy pregnant women (control group) who underwent fetal echocardiography were prospectively included in this study. The fetal HQ technique was applied to compare the differences in the global sphericity index (GSI), global strain values (GS), fractional area change (FAC), and 24-segment fractional shortening (FS) of the left and right ventricles, between the COVID-19 group and the control group.

RESULTS

Compared with the control group, the differences in GS and 24-segment FS of the left ventricle in the COVID-19 group were not statistically significant. However, the COVID-19 group showed lower GSI values compared with the control group (1.24 vs 1.28). FAC (48.12%) of the left ventricle and GS (-23.55%), FAC (41.74%) of the right ventricle in the COVID-19 group were reduced compared with FAC (50.50%) of the left ventricle and GS (-27.63%), FAC (46.01%) of the right ventricle in the control group. Segmental analysis revealed reduced FS in segments 20-24 in the COVID-19 group compared with the control group. Right ventricular GS was an independent predictor of adverse pregnancy outcome with an optimal cutoff value of -18.66%.

CONCLUSIONS

The results suggest that COVID-19 infection in early pregnancy may have a negative impact on fetal cardiac morphology and function. Fetal HQ may offer a new assessment method for the early identification of fetal cardiac alterations in pregnant women infected with COVID-19.

Interdependence of placenta and fetal cardiac development

The placenta and fetal heart undergo development concurrently during early pregnancy, and, while human studies have reported associations between placental abnormalities and congenital heart disease (CHD), the nature of this relationship remains incompletely understood. Evidence from animal studies suggests a plausible cause and effect connection between placental abnormalities and fetal CHD. Biomechanical models demonstrate the influence of mechanical forces on cardiac development, whereas genetic models highlight the role of confined placental mutations that can cause some forms of CHD. Similar definitive studies in humans are lacking; however, placental pathologies such as maternal and fetal vascular malperfusion and chronic deciduitis are frequently observed in pregnancies complicated by CHD. Moreover, maternal conditions such as diabetes and pre-eclampsia, which affect placental function, are associated with increased risk of CHD in offspring. Bridging the gap between animal models and human studies is crucial to understanding how placental abnormalities may contribute to human fetal CHD. The next steps will require new methodologies and multidisciplinary approaches combining innovative imaging modalities, comprehensive genomic testing, and histopathology. These studies may eventually lead to preventative strategies for some forms of CHD by targeting placental influences on fetal heart development.

The Placenta in Congenital Heart Disease: Form, Function and Outcomes

The maternal-fetal environment, controlled and modulated by the placenta, plays a critical role in the development and well-being of the fetus, with long-term impact through programming of lifelong health. The fetal cardiovascular system and placenta emerge at the same time embryologically, and thus placental form and function are altered in the presence of congenital heart disease (CHD). In this review, we report on what is known about the placenta from a structural and functional perspective when there is CHD. We describe the various unique pathologic findings as well as the diagnostic imaging tools used to characterize placental function in utero. With growing interest in the placenta, a standardized approach to characterizing placental pathology has emerged. Furthermore, application of ultrasonography techniques and magnetic resonance imaging now allow for insights into placental blood flow and functionality in vivo. An improved understanding of the intriguing relationship between the placenta and the fetal cardiovascular system will provide opportunities to develop novel ways to optimize outcomes. Once better understood, therapeutic modulation of placental function offered during the vulnerable period of fetal plasticity may be one of the most impactful ways to alter the course of CHD and its complications.

Cerebroplacental hemodynamics in fetuses with transposition of the great arteries and usefulness in predicting neonatal condition

OBJECTIVES

Literature on cerebroplacental hemodynamics in fetuses with transposition of the great arteries (TGA) is scarce and provides conflicting results regarding the presence of a brain-sparing effect. The aims of this study were to examine Doppler parameters in the middle cerebral artery (MCA) and umbilical artery (UA) in a large cohort of fetuses with TGA, and to assess their possible utility in predicting the need for urgent balloon atrial septostomy (BAS) in the neonate.

METHODS

This was a retrospective observational study of fetuses diagnosed with TGA between 2008 and 2022 and an age-matched cohort of normal fetuses, conducted in a single tertiary fetal cardiology center. Medical records and echocardiographic examinations were reviewed to collect demographic, sonographic and follow-up data. Selected Doppler parameters were compared between fetuses with TGA and normal fetuses, as well as between TGA fetuses with and those without an associated ventricular septal defect (VSD), to assess the impact of this congenital heart defect on cerebroplacental circulation. Additionally, Doppler indices in patients with a restrictive foramen ovale (FO) were analyzed to identify potential predictors of the need for urgent BAS.

RESULTS

A total of 541 examinations of 159 fetuses with TGA performed between 19 and 40 weeks' gestation and 1300 examinations of 1215 age-matched normal fetuses were included in the study. MCA pulsatility index (PI) and UA-PI followed expected trends throughout pregnancy, with slightly higher values observed in TGA fetuses, albeit within the limits for the normal population. Cerebroplacental ratio (CPR) values were similar in normal and TGA fetuses. The presence of a small VSD did not have a clinically significant impact on Doppler parameters. Peak systolic velocity (PSV) in the MCA increased gradually after 35 weeks' gestation, especially in fetuses that did not develop restriction of the FO after birth. MCA-PSV values below 1.16 multiples of the median measured at 38 weeks or later predicted the need for urgent BAS with 81.4% sensitivity and 52.4% specificity.

CONCLUSIONS

MCA-PI, UA-PI and CPR values in fetuses with TGA usually fall within normal limits throughout pregnancy. The presence of a small VSD does not affect the Doppler parameters significantly. MCA-PSV increases in TGA fetuses after 35 weeks, and its value measured at the last prenatal examination (ideally after 37 weeks) may serve as an additional predictive factor for the need for urgent BAS. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.

Evaluation of Intracranial Structures of Fetuses With Congenital Heart Defects

OBJECTIVES

We classified congenital heart defects (CHDs) according to cerebral blood flow oxygenation and aimed to evaluate the effect on the size of brain structures in these fetuses.

METHODS

The study which was designed retrospectively, included 28 patients with fetal CHDs and 76 patients without fetal anomalies.

RESULTS

The width and length of the cavum septum pellucidum significantly increased in the CHD group (P = .002, P = .004). The biparietal diameter and z scores were significantly lower in the single ventricle (SV) (P = .006, P = .019), and the head circumference (HC) and z scores were significantly lower in the transposition of great arteries (TGA) (P = .013, P = .038). The transverse cerebellar diameter, the cerebellar HC and the cerebellar hemisphere area values were lower in the SV (P = .005, P = .017, P = .044).

CONCLUSIONS

Brain structure changes are more pronounced in groups with low cerebral oxygenation, especially in the SV and the TGA.

Patterns of placental injury in various types of fetal congenital heart disease

OBJECTIVES

Fetal blood circulation may be modified in congenital heart disease (CHD). This retrospective analysis was performed to study whether the type of CHD is associated with specific placental pathology.

METHODS

3 types of CHD based on presumed proportion of placental and systemic blood distribution in fetal circulation were analyzed: Group 1: 89 cases with low placental blood content (hypoplastic left heart syndrome, transposition of great arteries, coarctation of aorta), Group 2: 71 placentas with intermediate placental and systemic blood content due to increased intracardiac blood mixing (tetralogy of Fallot, truncus arteriosus, double inlet/outlet ventricle), and Group 3: 24 placentas with high placental blood content (tricuspid or pulmonary atresia, Ebstein anomaly). Frequencies of 27 independent clinical and 47 placental phenotypes of 184 placentas in those three groups were statistically compared.

RESULTS

The most advanced gestational age at delivery, and large vessel (global) fetal vascular malperfusion (FVM) were most common in Group 1, while macerated stillbirths, neonatal mortality, abnormal amniotic fluid volume (oligohydramnios or polyhydramnios), other congenital anomalies, distal villous lesions of FVM, placental edema and amnion nodosum were most common in Groups 2 and 3, although the frequencies of placental lesions were statistically not significant.

CONCLUSIONS

Left heart obstructive lesions potentially associated with brain maldevelopment show increase in lesions of global FVM (in aggregate and individually fetal vascular ectasia, stem vessel obliteration and intramural fibrin deposition) as may be seen in umbilical cord compromise. CHD with increased intracardiac blood mixing or with right heart defects is associated with average preterm gestational age at delivery and placental lesions of distal villous FVM, villous edema and amnion nodosum.

Early Cerebrovascular Autoregulation in Neonates with Congenital Heart Disease

Neonates with congenital heart disease (CHD) display delayed brain development, predisposing them to impaired cerebrovascular autoregulation (CAR) and ischemic brain injury. For this paper, we analyzed the percentage of time with impaired CAR (%time impaired CAR) during the first 72 h after birth, the relation with clinical factors, and survival in 57 neonates with CHD. The primary outcome was a correlation coefficient of cerebral oxygenation (rcSO2) and mean arterial blood pressure (MABP, mmHg) for two hours on a daily basis. The %time impaired CAR ranged from 9.3% of the studied time on day one to 4.6% on day three. Variables associated with more %time impaired CAR were the use of inotropes (day 1, B = 19.5, 95%CI = 10.6-28.3; day 3, B = 11.5, 95%CI = 7.1-16), lower MABP (day 1, B = -0.6, 95%CI = -1.2-0.0), and dextro-transposition of the great arteries (dTGA) (16.2%) compared with other CHD types (2.0-5.0%; day 1, p = 0.022). Survival was not an associated variable. To summarize, impaired CAR was found in CHD neonates in up to 9.3% of the studied time. More evidence is necessary to evaluate an association with inotropes, dTGA, %time impaired CAR, and long-term outcome, further in larger cohorts.

Near-Term Cerebroplacental Doppler, Heart Morphology, and Neonatal Biometry in Hypoplastic Left Heart Syndrome

OBJECTIVES

To analyze near-term cerebroplacental Doppler, heart morphology, and neonatal biometry in isolated hypoplastic left heart syndrome (HLHS) relative to healthy controls.

METHODS

This retrospective study included 55 fetuses with HLHS (29 with mitral valve stenosis [MS]/aortic valve atresia [AA], 14 with MS/aortic valve stenosis, and 12 with mitral valve atresia [MA]/[AA]) diagnosed prenatally between 2010 and 2019 at 2 referral centers and 101 healthy controls. Ultrasound assessment included umbilical artery (UA), middle cerebral artery (MCA) pulsatility index (PI), and cerebroplacental ratio (CPR), with neonatal weight, length, head circumference (HC), Apgar score, and UA pH measured at birth.

RESULTS

In total, 32.7% of HLHS fetuses had abnormal MCA-PI and UA-PI, and 38.2% had CPRs below the fifth percentile before birth. All tested Doppler parameters differed from those of the healthy controls (P ≤ .01). Birth weight and length were comparable between HLHS and control fetuses, whereas birth HCs were smaller in the HLHS group than in the control group (P = .018). In both groups, increased UA-PI correlated with lower birth weight, but only HLHS fetuses with UA-PI > the 95th percentile had a lower median HC at birth than those with normal UA-PI (P = .045). The median UA-PI percentile was higher in fetuses with MA than in fetuses with MS (P = .015). The ascending aortic diameter correlated with birth weight (P = .036) and birth length (P = .039).

CONCLUSION

Abnormal cerebroplacental hemodynamics are evident in a high percentage of near-term fetuses with HLHS, and increased placental resistance may contribute to birth weight and HC. Moreover, heart morphology may impact placental circulation and neonatal biometry.

Longitudinal changes in fetal head biometry and fetoplacental circulation in fetuses with congenital heart defects

INTRODUCTION

Objectives were to analyze changes in fetal cephalic biometry and fetoplacental circulation throughout pregnancy in fetuses with congenital heart defects.

MATERIAL AND METHODS

Prospective study conducted on three university tertiary referral hospitals. Fetuses with the diagnosis of isolated congenital heart defects attending between 2014 and 2018 were included. Congenital heart defects were divided into two groups according to the oxygen supply to the central nervous system: group I (expected low placental blood content and low oxygen delivery to the brain) and group II (expected intermediate and high placental blood content). Fetal biometry and Doppler parameters were collected between 25-30 weeks of gestation and 34-40 weeks of gestation and transformed into Z scores. The results were compared with healthy controls. Finally, general linear modeling was performed to analyze repeated measurements.

RESULTS

In all, 71 fetuses met the inclusion criteria. Fetuses with congenital heart defects had significantly smaller head (biparietal diameter [p < 0.001], head circumference [p = 0.001]) and abdominal circumference (p < 0.001), and lower estimated fetal weight (p < 0.001) than controls. When analyzing according to congenital heart defects type, head size was significantly smaller in group I compared with group II (p = 0.04). Regarding Doppler parameters, fetuses with congenital heart defects showed higher umbilical artery pulsatility index (p < 0.001) and lower cerebroplacental ratio (p = 0.044) than controls. In group I, umbilical artery pulsatility index was above the 95th centile in 15.4% of fetuses compared with 6.7% in group II and 1.9% in controls (p < 0.001); moreover, middle cerebral artery pulsatility index was below the 5th centile in 5.4% of group I fetuses compared with 0% in group II and 1.2% in controls (p = 0.011). General linear model for two measurements showed significant longitudinal changes in biometric parameters. Growth rate of fetal head through pregnancy (head circumference Z score) was lower in fetuses with congenital heart defects compared with controls (p = 0.043). In group I, the head circumference Z score longitudinal decrease was significantly higher than in group II (p < 0.001).

CONCLUSIONS

Fetuses with congenital heart defects are at risk of smaller head size and Doppler changes. Growth rate of fetal head throughout pregnancy is also affected. These findings are mainly associated with cardiac defects with expected low oxygen supply to the central nervous system.

Alterations in Cardiac Output in Fetuses with Congenital Heart Disease

OBJECTIVE

Fetuses with severe congenital heart disease (CHD) have altered blood flow patterns. Prior work to assess fetal combined cardiac output (CCO) is limited by sample size and lack of longitudinal gestational data. Our aim was to evaluate CCO in CHD fetuses to determine whether the presence of single ventricle (SV) physiology or aortic obstruction impacts fetal blood flow and cardiovascular hemodynamics.

METHOD

Prospective study including singleton fetuses with CHD (n=141) and controls (n=118) who underwent a mid and late gestation fetal echocardiogram. Ventricular cardiac output was calculated using the standard computation. CCO was derived as the sum of the right and left cardiac outputs and indexed to estimated fetal weight.

RESULTS

Fetuses with two ventricle (2V) CHD had significantly higher CCO compared to controls and SV-CHD fetuses. Fetuses with SV-CHD had similar CCO compared to controls. Fetuses with 2V-CHD and aortic obstruction had significantly higher CCO than fetuses with SV-CHD and aortic obstruction.

CONCLUSION

Our findings suggest that the SV can compensate and increase CCO despite the lack of a second functioning ventricle however, the degree of compensation may be insufficient to support the increased blood flow needed to overcome the hemodynamic and physiologic alternations seen with severe CHD. This article is protected by copyright. All rights reserved.

Birthweight and isolated congenital heart defects - A systematic review and meta-analysis

Background

Birthweight (BW) is an important prognostic factor in newborns with congenital heart defects (CHD).

Objectives

To give an overview of the literature on BW z‐score in children with isolated CHD.

Search strategy

A systematic search was performed on isolated CHD and BW in PubMed, Embase, Web of Science, COCHRANE Library and Emcare.

Selection criteria

Neonates with isolated CHD were included if a BW percentile, BW z‐score or % small‐or‐gestational age (SGA) was reported.

Data collection and analysis

BW z‐score and percentage SGA were pooled with random‐effect meta‐analysis. Quality and risk of bias were assessed using the modified Newcastle Ottawa Scale.

Main results

Twenty‐three articles (27 893 cases) were included. BW z‐scores were retrieved from 11 articles, resulting in a pooled z‐score of −0.20 (95% CI −0.50 to 0.11). The overall pooled prevalence of SGA <10th percentile was 16.0% (95% CI 11.4–20.5; 14 studies). Subgroup analysis of major CHD showed similar results (BW z‐score −0.23 and percentage SGA 16.2%).

Conclusions

Overall BW in isolated CHD is within range of normality but impaired, with a 1.6‐fold higher risk of SGA, irrespective of the type of CHD (major CHD vs all CHD combined). Our findings underline the association between CHD and BW. The use of BW z‐scores provides insight into growth of all fetuses with CHD.

Tweetable abstract

Infants with a congenital heart defect (CHD) have a lower birthweight z‐score and a higher incidence of small‐for‐gestational age (<10th percentile). This was encountered both in the major CHD‐group as well as in all‐CHD combined group analysis. Future research on the association between birthweight and CHD should include all types of CHDs (including mild cardiac defects) and placental‐related disease, such as pre‐eclampsia. We advocate the use of international standardised fetal growth and birthweight charts in CHD research.

Infants with a congenital heart defect (CHD) have a lower birthweight z‐score and a higher incidence of small‐for‐gestational age (<10th percentile). This was encountered both in the major CHD‐group as well as in all‐CHD combined group analysis. Future research on the association between birthweight and CHD should include all types of CHDs (including mild cardiac defects) and placental‐related disease, such as pre‐eclampsia. We advocate the use of international standardised fetal growth and birthweight charts in CHD research.

Placenta morphology and biomarkers in pregnancies with congenital heart disease - A systematic review

Impaired placentation is an important contributing factor to intra-uterine growth restriction and pre-eclampsia in fetuses with congenital heart defects (CHD). These pregnancy complications occur more frequently in pregnancies with fetal CHD. One of the most important factors influencing the life of children with CHD is neurodevelopmental delay, which seems to start already in utero. Delayed neurodevelopment in utero may be correlated or even (partly) explained by impaired placentation in CHD cases. This systematic review provides an overview of published literature on placental development in pregnancies with fetal CHD. A systematic search was performed and the Newcastle-Ottawa scale was used to access data quality. Primary outcomes were placenta size and weight, vascular and villous architecture, immunohistochemistry, angiogenic biomarkers and/or placental gene expression. A total of 1161 articles were reviewed and 21 studies were included. Studies including CHD with a genetic disorder or syndrome and/or multiple pregnancies were excluded. Lower placental weight and elevated rates of abnormal umbilical cord insertions were found in CHD. Cases with CHD more frequently showed microscopic placental abnormalities (i.e. abnormal villous maturation and increased maternal vascular malperfusion lesions), reduced levels of angiogenic biomarkers and increased levels of anti-angiogenic biomarkers in maternal serum and umbilical cord blood. Altered gene expression involved in placental development and fetal growth were found in maternal serum and CHD placentas. In conclusion, abnormal placentation is found in CHD. More extensive studies are needed to elucidate the contribution of impaired placentation to delayed neurodevelopment in CHD cases.

Placental abnormalities in congenital heart disease

Congenital heart disease (CHD) remains the most common birth defect in infants, and critical CHD is associated with significant rates of morbidity and mortality. With the advent of powerful yet noninvasive advanced fetal imaging, it is becoming increasingly evident that the presence of CHD in utero disrupts typical development and contributes to the lifelong morbidity in this population. Across healthy and high-risk populations, intrauterine influences can permanently alter fetal development that may manifest in complex morbidities later in life, the so-called fetal-onset-of-adult-disease (FOAD) phenomenon. The placenta plays a critical role in not only supporting fetal development, but also by adapting to specific intrauterine conditions. The role of placental health, adaptation and dysfunction, however, in CHD is not well understood. In this article, we will review current evidence relating placental health in CHD, appraise existing knowledge-gaps in the field and highlight promising new avenues to better understand the impact of placental function on fetal well-being. We will review evidence of ex vivo human placental studies that describe abnormal placental findings in pregnancies complicated by CHD, as well evidence for in vivo assessments of the human placenta. While overall clinical in vivo assessments of placental development are rather limited, we will also review emerging evidence from advanced quantitative and functional magnetic resonance imaging that are bringing new insights into placental structure and function throughout gestation. By providing novel information about placental development, we can now explore the maternal-fetal-placental connection in greater detail, and better understand the multi-factorial mechanisms that may contribute to adverse outcomes seen in survivors of CHD.

Cerebroplacental and Uterine Doppler Indices in Pregnancies Complicated by Congenital Heart Disease of the Fetus

PURPOSE

 Children with congenital heart disease (CHD) are known to have impaired neurodevelopment possibly influenced by altered cerebroplacental hemodynamics antenatally. We compared fetomaternal Doppler patterns in different CHD groups with published normative values during gestation.

MATERIALS AND METHODS

 Retrospective cohort study consisting of 248 CHD fetuses. Subgroups were generated according to the expected ascending aorta oxygen saturation: low portion of high oxygenated umbilical venous (UV) blood (group 1: n = 108), intermediate portion of UV blood due to intracardiac mixing with oxygen poor systemic blood (group 2: n = 103), high (group 3: n = 13) and low portion of UV blood without mixing of blood (group 4: n = 24). Doppler examination included umbilical artery and middle cerebral artery pulsatility index (UA-PI, MCA-PI), cerebroplacental ratio (CPR) and mean uterine artery (mUtA) PI. For mean comparisons at different gestational ages (GA), estimated marginal means from regression models are reported for GA 22 weeks (wks), GA 30 wks and GA 38 wks.

RESULTS

 Z-score transformed values of MCA-PI (zMCA-PI) were significantly lower in group 1 compared to all other subgroups at GA 30 wks (p < 0.05). At 38 wks, group 1 had significantly lower values of zMCA-PI and zCPR compared to groups 2 and 4. Group 1 fetuses showed a significant association between zMCA-PI and zCPR (negative) and GA as well as zmUtA-PI (positive) and GA compared to reference values.

CONCLUSION

 Our data confirm that CHD fetuses have a higher rate of cerebral redistribution in the third trimester. Changes in Doppler patterns were mainly observed in CHD with a low portion of UV blood in the ascending aorta.

Mid-gestational fetal placental blood flow is diminished in the fetus with congenital heart disease

OBJECTIVE

Data suggest fetuses with congenital heart disease (CHD) have placental abnormalities. Their abnormal placental vasculature may affect fetal placental blood flow, which has not previously been explored.

METHOD

We performed a retrospective cross-sectional study comparing umbilical venous volume flow (UVVF) of single ventricle, D-transposition of the great arteries, and tetralogy of Fallot fetuses with fetuses without CHD. UVVF and combined cardiac output (CCO) were calculated from fetal echocardiography and compared using t tests, χ² and Fisher's exact tests.

RESULTS

Mean gestational age and fetal weight were greater in CHD fetuses (26.5 weeks, 1119.4 g; n = 81, P < .001) compared to controls (23.1 weeks, 675 g; n = 170, P < .001). UVVF/fetal weight was nevertheless decreased among cases (99.8 vs 115.3 mL/min/kg, P < .001). Subgroup analysis of 20- to 25-week fetuses demonstrated no significant differences in case and control baseline characteristics. In CHD fetuses (n = 31) compared to controls (n = 144), absolute UVVF (50.8 vs 62.1 mL/min, P = .006), and UVVF/fetal weight (98.8 vs 118.5 mL/min/kg, P < .001) were decreased. Findings were similar in single ventricle (n = 24) and hypoplastic left heart syndrome (n = 14).

CONCLUSION

Mid-gestational placental blood flow in CHD fetuses is decreased compared to controls. Further study is needed to explore the relationship between UVVF and placental pathology, and impact on outcomes.

Impact of extracardiac pathology on head growth in fetuses with congenital heart defect

OBJECTIVE

Neurodevelopmental delay is frequently encountered in children with a congenital heart defect (CHD). Fetuses with major CHD have a smaller head circumference (HC), irrespective of altered cerebral flow or brain oxygenation. This cohort study compared head growth in cases with isolated vs those with non-isolated CHD to evaluate the effect of additional pathology on head size in these fetuses.

METHOD

All CHD cases diagnosed prenatally in the period January 2002-July 2014 were selected from our regional registry, PRECOR. Cases of multiple pregnancy, and those affected by maternal diabetes, severe fetal structural brain anomalies or functional CHD were excluded. Subjects were divided into groups according to whether the CHD was isolated, and the non-isolated group was subdivided into three groups: cases with genetic anomaly, extracardiac malformation or placental pathology. In both isolated and non-isolated CHD groups, CHDs were also grouped according to their potential effect on aortic flow and oxygen saturation. Mean HC Z-scores at 20 weeks and increase or decrease (Δ) of HC Z-scores over the course of pregnancy were compared between isolated and non-isolated groups, using mixed linear regression models.

RESULTS

Included were 916 cases of CHD diagnosed prenatally, of which 378 (41.3%) were non-isolated (37 with placental pathology, 217 with genetic anomaly and 124 with extracardiac malformation). At 20 weeks, non-isolated cases had significantly lower HC Z-scores than did isolated cases (Z-score = -0.70 vs -0.03; P < 0.001) and head growth over the course of pregnancy showed a larger decrease in this group (Δ HC Z-score = -0.03 vs -0.01 per week; P = 0.01). Cases with placental pathology had the lowest HC Z-score at 20 weeks (Z-score = -1.29) and the largest decrease in head growth (Δ HC Z-score = -0.06 per week). In CHD subjects with a genetic diagnosis (Z-score = -0.73; Δ HC Z-score = -0.04 per week) and in those with an extracardiac malformation (Z-score = -0.49; Δ HC Z-score = -0.02 per week), HC Z-scores were also lower compared with those in subjects with isolated CHD. CHDs that result in low oxygenation or flow to the brain were present more frequently in isolated than in non-isolated cases.

CONCLUSIONS

Smaller HC in fetuses with CHD appears to be associated strongly with additional pathology. Placental pathology and genetic anomaly in particular seem to be important contributors to restricted head growth. This effect appears to be irrespective of altered hemodynamics caused by the CHD. Previously reported smaller HC in CHD should, in our opinion, be attributed to additional pathology. Neurodevelopment studies in infants with CHD should, therefore, always differentiate between isolated and non-isolated cases. © 2019 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of the International Society of Ultrasound in Obstetrics and Gynecology.

Application of the INTERGROWTH-21st chart compared to customized growth charts in fetuses with left heart obstruction: late trimester biometry, cerebroplacental hemodynamics and perinatal outcome

PURPOSE

Birth weight (BW) is crucial for surgical outcome in children with left heart obstruction (LHO). Head circumference (HC) is believed to correlate with the neurocognitive outcome in LHO. Our aim was to investigate the application of international standardized growth charts from the INTERGROWTH-21st project in comparison to customized growth charts in fetal LHO.

METHODS

This is a retrospective cohort study consisting of 60 singleton pregnancies complicated by fetal LHO. For the z score calculation of estimated fetal weight (EFW) and biometric parameters, the INTERGROWTH-21st calculator was used as well as algorithms of customized growth charts. Antenatal measurements were compared to newborn biometry and the association with fetal Doppler results (MCA PI: middle cerebral artery pulsatility index and CPR: cerebroplacental ratio) was examined. Furthermore, the ability of each antenatal chart to predict adverse perinatal outcome was evaluated.

RESULTS

At a mean gestational age of 37 weeks, all assessment charts showed significantly smaller mean values for antenatal head circumference (HC) z scores. Highest detection rate for restricted HC growth antenatally was achieved with Hadlock charts. MCA PI and CPR were not associated with neonatal HC. A significant association was observed between EFW and 1-year survival, independent of the considered growth chart.

CONCLUSIONS

Growth chart independently, antenatal HC did tend to be smaller in LHO fetuses. A significant association was observed between EFW and 1-year survival rate. Prospective investigations in CHD fetuses should be carried out with internationally standardized growth charts to better examine their prognostic value in this high-risk population.