Long-Term Neurodevelopmental Outcomes of Children with Congenital Heart Defects

Novel Insights in Perioperative Neuroprotection in Neonatal Congenital Heart Disease

Congenital heart disease (CHD) includes defects of intrauterine cardiac development that result in alterations to the morphology and/or physiology of the heart, usually expressed early in fetal or postnatal life. This group represents one of the most common congenital anomalies of all living newborns worldwide. Neurodevelopmental deficits are a reality in patients with CHDs and may contribute to significant sequela and long-term morbidity beginning in infancy and extending into adulthood. There is general agreement that the perioperative period of neonatal cardiac surgery may be responsible for a significant burden of lifelong neurological injury in patients with CHDs. Recent research has advanced understanding of neurodevelopmental trajectories, factors that increase neurodevelopmental risk, and neuroprotective strategies for patients with these disorders. In the present study, we aim to describe the different emerging strategies for neuroprotection in the perioperative period in neonatal patients with congenital heart disease.

Perioperative Factors Associated with 2-Year Neurodevelopmental Outcome in Neonates Undergoing Congenital Cardiac Surgery with Cardiopulmonary Bypass: A Single-Center Cohort Study

Advances in neonatal cardiac surgery have significantly reduced mortality rates for complex congenital heart diseases (CHD). However, long-term morbidities, particularly neurodevelopmental (NDV) outcomes, remain a concern. Perioperative factors implicated in NDV delays are less described. This study aimed to assess NDV outcomes at 2 years in a cohort of neonates undergoing cardiopulmonary bypass (CPB) and identify perioperative variables associated with non-optimal NDV. This analysis included neonates from the Loire Infant Follow-up Team (LIFT) cohort who underwent CPB between 2014 and 2021. NDV outcomes were assessed at 24 months using the Ages and Stages Questionnaire (ASQ-2) and/or expert clinical evaluations. Non-optimal NDV was defined as two or more ASQ domains below cut-off values or a clinical diagnosis of neurodevelopmental delay. Of 254 neonates operated on 84 were analyzed. Non-optimal NDV was observed in 11 patients (13.1%), while 65 (77.4%) were classified as having Optimal NDV. Motor and cognitive delays were infrequent (5%), and language delays were observed in 9.5% of cases. No association between major complication during post-operative period and non-optimal NDV was found. Maximal serum lactate levels during the first 72 postoperative hours were significantly associated with non-optimal NDV after adjusting for RACHS category (adjusted odds ratio: 1.41 per mmol/L above 2.2 mmol/L, p = 0.04). Contemporary neonatal cardiac surgery shows encouraging NDV outcomes, with achieving normal development by 2 years. Elevated postoperative lactate levels, used as a surrogate of serious events occurring during the post-operative period, were associated with non-optimal NDV, highlighting the importance of optimizing perioperative care. Larger studies with extended follow-up are needed to validate these findings and explore additional modifiable predictors of long-term outcomes.

Developmental and Psychological Concerns in Children With Complex Congenital Heart Disease: The Need for a Screening Program

AIM

Complex congenital heart disease (CHD) is associated with adverse neurodevelopmental and psychological outcomes. Limited Australian data exist regarding these outcomes or follow-up. This cross-sectional study aims to determine the prevalence of developmental and psychological concerns in South Australian children with complex CHD and concurrent developmental or psychological healthcare utilisation.

METHODS

Families of children with complex CHD aged between 3 years and 7 years 11 months undertook a series of validated screening questionnaires for development (Parents' Evaluation of Developmental Status [PEDS], Parents' Evaluation of Developmental Status-Developmental Milestones [PEDS:DM]) and mental health (Strengths and Difficulties Questionnaire [SDQ]). Demographic data, cardiac history, comorbidities, and current healthcare engagement was determined through standardised patient information questionnaires and medical records. Rates of developmental and psychological concern were determined and compared to Australian general population data.

RESULTS

Fifty-five participants enrolled in the study. The most common cardiac diagnoses were Transposition of the Great Arteries (n = 13) and Tetralogy of Fallot (n = 11). Predictive developmental domain/s of concern were highly prevalent utilising both PEDS (57%) and PEDS:DM (70%) screening tools, exceeding Australian population rates (22%). Psychological concern (28%) also exceeded Australian population data (10%). Nearly half of participants identified to have developmental or psychological concern/s had no current general paediatric, allied health or mental health professional engagement.

CONCLUSIONS

Developmental and psychological concerns detected on screening in children with complex CHD significantly exceed Australian general population prevalence rates. Without an established screening program, a large proportion of participants did not have active follow-up, indicating the importance of routine screening.

Randomized Trial of Pulsatile and Nonpulsatile Flow in Cyanotic and Acyanotic Congenital Heart Surgery

BackgroundThe study objective was to determine the impact of cardiopulmonary bypass perfusion modalities on cerebral hemodynamics and clinical outcomes in congenital cardiac surgery patients stratified by acyanotic versus cyanotic heart disease.MethodsA total of 159 pediatric (age <18 years) cardiac surgery patients were prospectively randomized to pulsatile or nonpulsatile cardiopulmonary bypass and stratified by type of congenital heart disease: acyanotic versus cyanotic. Intraoperative cerebral gaseous microemboli counts and middle cerebral artery pulsatility index were assessed. Organ injury was quantified by Pediatric Logistic Organ Dysfunction-2 (PELOD-2) score at 24, 48, and 72 h postoperatively. Additional outcomes included Pediatric Risk of Mortality-3 score, vasoactive-inotropic score, duration of mechanical ventilation, intensive care and hospital length of stay, and 180-day mortality. Heterogenous variance linear models (ie, ANOVA and mixed models) and χ2 tests were used to compare groups for continuous and categorical variables, respectively.ResultsWithin congenital heart disease subgroups, patients randomized to nonpulsatile versus pulsatile bypass had similar preoperative and operative characteristics. While the intraoperative pulsatility index was higher in the pulsatile subset of both acyanotic and cyanotic groups (P < .05), regional cerebral oxygen saturation, mean arterial pressure, and gaseous microemboli counts were similar. Postoperative PELOD-2 scores decreased at similar rates in the acyanotic and cyanotic subgroups regardless of the perfusion modality utilized. There were also no significant between-group differences in the additional postoperative outcomes by perfusion modality in either acyanotic or cyanotic groups.ConclusionsDespite patients undergoing pulsatile cardiopulmonary bypass experiencing a more physiologic pulsatility index in both acyanotic and cyanotic groups, no significant differences in cerebral hemodynamics or clinical outcomes were appreciated.

Congenital Heart Defects and Apgar Score at Birth, a Nationwide Study

BACKGROUND

Low Apgar scores have been associated with an increased risk of brain injury and neurodevelopmental disorders in newborns with congenital heart defects (CHDs). However, the relation between CHD subtypes and low Apgar scores remains unknown. This study aimed to assess the association between major subtypes of CHD and low (<7) Apgar scores at 5 minutes.

METHODS AND RESULTS

This population-based study included 1 040 474 liveborn singletons in Denmark from 1997 to 2013. The association between CHD and low Apgar scores was estimated by confounder-adjusted, multivariable logistic regression. In mediation analyses, the underlying mechanisms were examined. Low Apgar scores were present in 3.0% of newborns with CHD and in 0.7% of newborns without CHD. Overall, CHD was associated with an increased risk of a low Apgar score (adjusted odds ratio, 2.5 [95% CI, 2.1-3.0]). CHD subtypes associated with the highest risks were anomalous pulmonary venous return (adjusted odds ratio, 5.7 [95% CI, 2.2-14.9]), hypoplastic left heart syndrome (adjusted odds ratio, 5.1 [95% CI, 2.2-11.8]), and transposition of the great arteries (adjusted odds ratio, 3.5 [95% CI, 1.7-7.4]). In mediation analyses, preterm birth explained 25.2% (95% CI, 11.8-38.6) of the association between CHD and low Apgar scores.

CONCLUSIONS

Nearly all CHD subtypes were associated with an increased risk of a low Apgar score. The association was most pronounced in severe and potentially cyanotic types of CHD. These findings suggest that CHD is associated with a complicated fetal-to-neonatal transition and highlight the potential for improvements of this process in infants with CHD.

Gut Microbiota Influences Developmental Anesthetic Neurotoxicity in Neonatal Rats

BACKGROUND

Anesthetic exposure during childhood is significantly associated with impairment of neurodevelopmental outcomes; however, the causal relationship and detailed mechanism of developmental anesthetic neurotoxicity remain unclear. Gut microbiota produces various metabolites and influences the brain function and development of the host. This relationship is referred to as the gut-brain axis. Gut microbiota may influence developmental anesthetic neurotoxicity caused by sevoflurane exposure. This study investigated the effect of changes in the composition of gut microbiota after fecal microbiota transplantation on spatial learning disability caused by developmental anesthetic neurotoxicity in neonatal rats.

METHODS

Neonatal rats were allocated into the Control (n = 10) and Sevo (n = 10) groups in Experiment 1 and the Sevo (n = 20) and Sevo+FMT (n = 20) groups in Experiment 2, according to the randomly allocated mothers' group. The rats in Sevo and Sevo+FMT groups were exposed to 2.1% sevoflurane for 2 hours on postnatal days 7 to 13. Neonatal rats in the Sevo+FMT group received fecal microbiota transplantation immediately after sevoflurane exposure on postnatal days 7 to 13. The samples for fecal microbiota transplantation were obtained from nonanesthetized healthy adult rats. Behavioral tests, including Open field, Y-maze, Morris water maze, and reversal Morris water maze tests, were performed to evaluate spatial learning ability on postnatal days 26 to 39.

RESULTS

Experiment 1 revealed that sevoflurane exposure significantly altered the gut microbiota composition. The relative abundance of Roseburia (effect value: 1.01) and Bacteroides genus (effect value: 1.03) increased significantly after sevoflurane exposure, whereas that of Lactobacillus (effect value: -1.20) decreased significantly. Experiment 2 revealed that fecal microbiota transplantation improved latency to target (mean ± SEM; Sevo group: 9.7 ± 8.2 seconds vs, Sevo+FMT group: 2.7 ± 2.4 seconds, d=1.16, 95% confidence interval: -12.7 to -1.3 seconds, P = .019) and target zone crossing times (Sevo group: 2.4 ± 1.6 vs, Sevo+FMT group: 5.4 ± 1.4, d=1.99, 95% confidence interval: 2.0-5.0, P < .001) in the reversal Morris water maze test. Microbiota analysis revealed that the α-diversity of gut microbiota increased after fecal microbiota transplantation. Similarly, the relative abundance of the Firmicutes phylum (effect value: 1.44), Ruminococcus genus (effect value: 1.69), and butyrate-producing bacteria increased after fecal microbiota transplantation. Furthermore, fecal microbiota transplantation increased the fecal concentration of butyrate and induced histone acetylation and the mRNA expression of brain-derived neurotrophic factor in the hippocampus, thereby suppressing neuroinflammation and neuronal apoptosis.

CONCLUSIONS

The alternation of gut microbiota after fecal microbiota transplantation influenced spatial learning ability in neonatal rats with developmental anesthetic neurotoxicity. Modulation of the gut microbiota may be an effective prophylaxis for developmental anesthetic neurotoxicity in children.

Inferring neurocognition using artificial intelligence on brain MRIs

Brain magnetic resonance imaging (MRI) offers a unique lens to study neuroanatomic support of human neurocognition. A core mystery is the MRI explanation of individual differences in neurocognition and its manifestation in intelligence. The past four decades have seen great advancement in studying this century-long mystery, but the sample size and population-level studies limit the explanation at the individual level. The recent rise of big data and artificial intelligence offers novel opportunities. Yet, data sources, harmonization, study design, and interpretation must be carefully considered. This review aims to summarize past work, discuss rising opportunities and challenges, and facilitate further investigations on artificial intelligence inferring human neurocognition.

[Research progress on neurodevelopmental disorders associated with congenital heart disease]

The incidence and disability rate of neurodevelopmental disorders in children are high, making it a significant public health issue affecting children's health globally. Neurodevelopmental disorders are particularly common in children with congenital heart disease (CHD), with clinical characteristics varying by type of CHD, surgical approach, age stage, and the presence of different complications or comorbidities. In recent years, based on the intervention model of "early diagnosis and early treatment," foreign studies have begun to explore new techniques for preventive early intervention in high-risk children with neurodevelopmental disorders, achieving promising results. This paper reviews the clinical characteristics of neurodevelopmental disorders associated with CHD, aiming to provide a theoretical basis for implementing new preventive early intervention techniques for children with CHD, thereby further reducing the incidence of neurodevelopmental disorders associated with CHD.

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.

Exploring the origins of neurodevelopmental proteasomopathies associated with cardiac malformations: are neural crest cells central to certain pathological mechanisms?

Neurodevelopmental proteasomopathies constitute a recently defined class of rare Mendelian disorders, arising from genomic alterations in proteasome-related genes. These alterations result in the dysfunction of proteasomes, which are multi-subunit protein complexes essential for maintaining cellular protein homeostasis. The clinical phenotype of these diseases manifests as a syndromic association involving impaired neural development and multisystem abnormalities, notably craniofacial anomalies and malformations of the cardiac outflow tract (OFT). These observations suggest that proteasome loss-of-function variants primarily affect specific embryonic cell types which serve as origins for both craniofacial structures and the conotruncal portion of the heart. In this hypothesis article, we propose that neural crest cells (NCCs), a highly multipotent cell population, which generates craniofacial skeleton, mesenchyme as well as the OFT of the heart, in addition to many other derivatives, would exhibit a distinctive vulnerability to protein homeostasis perturbations. Herein, we introduce the diverse cellular compensatory pathways activated in response to protein homeostasis disruption and explore their potential implications for NCC physiology. Altogether, the paper advocates for investigating proteasome biology within NCCs and their early cranial and cardiac derivatives, offering a rationale for future exploration and laying the initial groundwork for therapeutic considerations.

Meta-regression of sulcal patterns, clinical and environmental factors on neurodevelopmental outcomes in participants with multiple CHD types

Congenital heart disease affects 1% of infants and is associated with impaired neurodevelopment. Right- or left-sided sulcal features correlate with executive function among people with Tetralogy of Fallot or single ventricle congenital heart disease. Studies of multiple congenital heart disease types are needed to understand regional differences. Further, sulcal pattern has not been studied in people with d-transposition of the great arteries. Therefore, we assessed the relationship between sulcal pattern and executive function, general memory, and processing speed in a meta-regression of 247 participants with three congenital heart disease types (114 single ventricle, 92 d-transposition of the great arteries, and 41 Tetralogy of Fallot) and 94 participants without congenital heart disease. Higher right hemisphere sulcal pattern similarity was associated with improved executive function (Pearson r = 0.19, false discovery rate-adjusted P = 0.005), general memory (r = 0.15, false discovery rate P = 0.02), and processing speed (r = 0.17, false discovery rate P = 0.01) scores. These positive associations remained significant in for the d-transposition of the great arteries and Tetralogy of Fallot cohorts only in multivariable linear regression (estimated change β = 0.7, false discovery rate P = 0.004; β = 4.1, false discovery rate P = 0.03; and β = 5.4, false discovery rate P = 0.003, respectively). Duration of deep hypothermic circulatory arrest was also associated with outcomes in the multivariate model and regression tree analysis. This suggests that sulcal pattern may provide an early biomarker for prediction of later neurocognitive challenges among people with congenital heart disease.

Importance of human milk for infants in the clinical setting: Updates and mechanistic links

INTRODUCTION

Human milk (HM) is the optimal source of nutrition for infants and has been implicated in multiple aspects of infant health. Although much of the existing literature has focused on the individual components that drive its nutrition content, examining HM as a biological system is needed for meaningful advancement of the field. Investigation of the nonnutritive bioactive components of HM and the maternal, infant, and environmental factors which affect these bioactives is important to better understand the importance of HM provision to infants. This information may inform care of clinical populations or infants who are critically ill, hospitalized, or who have chronic diseases and may benefit most from receiving HM.

METHODS

In this narrative review, we reviewed literature examining maternal and infant influences on HM composition with a focus on studies published in the last 10 years that were applicable to clinical populations.

RESULTS

We found multiple studies examining HM components implicated in infant immune and gut health and neurodevelopment. Additional work is needed to understand how donor milk and formula may be used in situations of inadequate maternal HM. Furthermore, a better understanding of how maternal factors such as maternal genetics and metabolic health influence milk composition is needed.

CONCLUSION

In this review, we affirm the importance of HM for all infants, especially clinical populations. An understanding of how HM composition is modulated by maternal and environmental factors is important to progress the field forward with respect to mechanistic links between HM biology and infant health outcomes.

Growth and risk of adverse neuro-developmental outcome in newborns with congenital heart disease: A single-centre retrospective study

BACKGROUND

Mortality in infants with CHD is decreasing and focus has shifted to improving long-term outcomes. Growth and neurodevelopmental outcomes are important long-term endpoints for both clinicians and parents.

OBJECTIVE

To evaluate growth and determine the impact of growth on neurodevelopmental outcomes at one year of age in infants who had an operative or therapeutic catheter procedure for CHD in neonatal period.

METHODS

This was a single-centre retrospective cohort study of infants born at term gestation with CHD. Demographic details, measurements of growth, and scores of Bayley Scales of Infant and Toddler Assessment (third edition), were collected. Enrolled study participants were categorised in subgroups based on the procedures required prior to one-year assessment. Regression analysis was performed to explore predictive ability of anthropometric measurements on mean scores of developmental assessment.

RESULTS

A total of 184 infants were included in the study. Mean z-scores for weight and head circumference at birth were age-appropriate. Mean scores for various developmental domains ranged from borderline to normal except for infants with single ventricular physiology who had gross motor delay concomitant with growth failure. In this group, z-score of weight at one-year-assessment predicted mean score of cognition (p-value 0.02), fine motor (p-value 0.03) and gross motor nearly (p-value 0.06).

CONCLUSIONS

Infants born at term gestation, with CHD, without genetic diagnosis had normal fetal growth. Postnatal growth restriction and developmental delay was most marked in infants with single ventricle physiology, suggesting careful nutritional and developmental monitoring.

Impact of cardiopulmonary bypass on cerebrovascular autoregulation assessed by ultrafast ultrasound imaging

Newborns with congenital heart disease undergoing cardiac surgery are at risk of neurodevelopmental impairment with limited understanding of the impact of intra-operative cardiopulmonary bypass (CPB), deep hypothermia and selective cerebral perfusion on the brain. We hypothesized that a novel ultrasound technique, ultrafast power Doppler (UPD), can assess variations of cerebral blood volume (CBV) in neonates undergoing cardiac surgery requiring CPB. UPD was performed before, during and after surgery in newborns with hypoplastic left heart syndrome undergoing a Norwood operation. We found that global CBV was not significantly different between patients and controls (P = 0.98) and between pre- and post-surgery (P = 0.62). UPD was able to monitor changes in CBV throughout surgery, revealing regional differences in CBV during hypothermia during which CBV correlated with CPB flow rate (R²  = 0.52, P = 0.021). Brain injury on post-operative magnetic resonance imaging was observed in patients with higher maximum variation in CBV. Our findings suggest that UPD can quantify global and regional brain perfusion variation during neonatal cardiac surgery with this first intra-operative application demonstrating an association between CBV and CPB flow rate, suggesting loss of autoregulation. Therefore, the measurement of CBV by UPD could enable optimization of cerebral perfusion during cardiac surgery in neonates. KEY POINTS: The impact of cardiopulmonary bypass (CPB) on the neonatal brain undergoing cardiac surgery is poorly understood. Ultrafast power Doppler (UPD) quantifies cerebral blood volume (CBV), a surrogate of brain perfusion. CBV varies throughout CPB surgery and is associated with variation of the bypass pump flow rate during deep hypothermia. Association between CBV and bypass pump flow rate suggests loss of cerebrovascular autoregulatory processes. Quantitative monitoring of cerebral perfusion by UPD could provide a direct parameter to optimize CPB flow rate.

The Genetics of Neurodevelopment in Congenital Heart Disease

Congenital heart disease (CHD) is the most common birth anomaly, affecting almost 1% of infants. Neurodevelopmental delay is the most common extracardiac feature in people with CHD. Many factors may contribute to neurodevelopmental risk, including genetic factors, CHD physiology, and the prenatal/postnatal environment. Damaging variants are most highly enriched among individuals with extracardiac anomalies or neurodevelopmental delay in addition to CHD, indicating that genetic factors have an impact beyond cardiac tissues in people with CHD. Potential sources of genetic risk include large deletions or duplications that affect multiple genes, such as 22q11 deletion syndrome, single genes that alter both heart and brain development, such as CHD7, and common variants that affect neurodevelopmental resiliency, such as APOE. Increased use of genome-sequencing technologies in studies of neurodevelopmental outcomes in people with CHD will improve our ability to detect relevant genes and variants. Ultimately, such knowledge can lead to improved and more timely intervention of learning support for affected children.

Growth and risk of adverse neuro-developmental outcome in infants with congenital heart disease: A systematic review

AIM

Congenital heart disease (CHD) is one of the most common birth defects affecting around 1:100 infants. In this systematic review, we aimed to determine impact of growth on neurodevelopmental outcomes of infants with CHD.

METHODS

Studies that reported association of growth with developmental outcomes in infants with CHD who had surgery, were included. The search strategy was prospectively registered. Relevant studies were identified by electronic searches. The Cochrane Central Register of Controlled Trials, MEDLINE and EMBASE were searched from their earliest date to February 2022.

RESULTS

Twenty studies met inclusion criteria. Choice of growth measures, developmental assessment tools and timing of assessment varied widely precluding conduct of a meta-analysis. Seventeen studies reported on infants who had cardio-pulmonary bypass. Birth weight was reported in thirteen studies and was associated with adverse outcome in nine. Head circumference at birth and later predicted developmental outcomes in five. Impaired postnatal growth was associated with adverse developmental outcome in seven studies.

CONCLUSION

Growth in infants with congenital heart disease, specifically single ventricle physiology can predict adverse neurodevelopmental outcome. Included studies showed significant clinical heterogeneity. Uniformity should be agreed by various data registries with routine prospective collection of growth and developmental data.

The horizon of pediatric cardiac critical care

Pediatric Cardiac Critical Care (PCCC) is a challenging discipline where decisions require a high degree of preparation and clinical expertise. In the modern era, outcomes of neonates and children with congenital heart defects have dramatically improved, largely by transformative technologies and an expanding collection of pharmacotherapies. Exponential advances in science and technology are occurring at a breathtaking rate, and applying these advances to the PCCC patient is essential to further advancing the science and practice of the field. In this article, we identified and elaborate on seven key elements within the PCCC that will pave the way for the future.