Brain maturation is delayed in infants with complex congenital heart defects

Deciphering the developmental order and microstructural patterns of early white matter pathways in a diffusion MRI based fetal brain atlas

White matter (WM) of the fetal brain undergoes rapid development to form early structural connections. Diffusion magnetic resonance imaging (dMRI) has shown to be a useful tool to depict fetal brain WM in utero, and many studies have observed increasing fractional anisotropy and decreasing diffusivity in the fetal brain during the second-to-third trimester, whereas others reported non-monotonic changes. Unbiased dMRI atlases of the fetal brain are important for characterizing the developmental trajectories of WM and providing normative references for in utero diagnosis of prenatal abnormalities. To date, the sole fetal brain dMRI atlas was collected from a Caucasian/mixed population and was constructed based on the diffusion tensor model with limited spatial resolution. In this work, we proposed a fiber orientation distribution (FOD) based pipeline for generating fetal brain dMRI atlases, which showed better registration accuracy than a diffusion tensor based pipeline. Based on the FOD-based pipeline, we constructed the first Chinese fetal brain dMRI atlas using 89 dMRI scans of normal fetuses at gestational age between 24 and 38 weeks. Complex non-monotonic trends of tensor- and FOD-derived microstructural parameters in eight WM tracts were observed, which jointly pointed to different phases of microstructural development. Specifically, we speculated that the turning point of the diffusivity trajectory may correspond to the starting point of pre-myelination, based on which, the developmental order of WM tracts can be mapped and the order was in agreement with the order of myelination from histological studies. The normative atlas also provided a reference for the detection of abnormal WM development, such as that in congenital heart disease. Therefore, the established high-order fetal brain dMRI atlas depicted the spatiotemporal pattern of early WM development, and findings may help decipher the distinct microstructural events in utero.

Neurodevelopmental outcomes after neonatal surgery

Children who require surgery in the newborn period are at risk for long-term neurodevelopmental impairment (NDI). There is growing evidence that surgery during this critical window of neurodevelopment gives rise to an increased risk of brain injury, predisposing to neurodevelopmental challenges including motor delays, learning disabilities, executive function impairments, and behavioral disorders. These impairments can have a significant impact on the quality of life of these children and their families. This review explores the current literature surrounding the effect of neonatal surgery on neurodevelopment, as well as the spectrum of proposed mechanisms that may impact neurodevelopmental outcomes. The goal is to identify modifiable risk factors and patients who may benefit from close neurodevelopmental follow-up and early referral to therapy.

Risk Factors for Tube Feeding at Discharge in Infants Undergoing Neonatal Surgery for Congenital Heart Disease: A Systematic Review

Approximately 30-50% of infants undergoing neonatal surgery for congenital heart disease (CHD) cannot meet oral feeding goals by discharge and require feeding tube support at home. Feeding tubes are associated with increased readmission rates and consequent hospital, payer, and family costs, and are a burden for family caregivers. Identification of modifiable risk factors for oral feeding problems could support targeted care for at-risk infants. Therefore, the aim of this systematic review is to determine risk factors for tube feeding at discharge in infants undergoing neonatal surgery for CHD. Following Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines, a search was conducted using MEDLINE, CINAHL, and Cochrane Database of Systematic Reviews. Studies published before 2010 were excluded. The search resulted in 607 records, of which 18 were included. Studies were primarily retrospective cohort designs and results were often inconsistent. Study quality was assessed using the Joanna Briggs Critical Appraisal Tools. As a group, the studies exhibited substantial risk for bias. Based on the findings, infants who struggle with feeding preoperatively, experience increased nil per os duration and/or low oral feeding volume postoperatively, experience increased duration of mechanical ventilation, or have vocal cord dysfunction may be at risk for tube feeding at hospital discharge. Factors warranting further examination include cardiac physiology (e.g., aortic arch obstruction) and the relationship between neurodevelopment and oral feeding. Clinicians should use caution in assuming risk for an individual and prioritize early implementation of interventions that facilitate oral feeding development.

Clinical factors associated with microstructural connectome related brain dysmaturation in term neonates with congenital heart disease

Objective

Term congenital heart disease (CHD) neonates display abnormalities of brain structure and maturation, which are possibly related to underlying patient factors, abnormal physiology and perioperative insults. Our primary goal was to delineate associations between clinical factors and postnatal brain microstructure in term CHD neonates using diffusion tensor imaging (DTI) magnetic resonance (MR) acquisition combined with complementary data-driven connectome and seed-based tractography quantitative analyses. Our secondary goal was to delineate associations between mild dysplastic structural brain abnormalities and connectome and seed-base tractography quantitative analyses. These mild dysplastic structural abnormalities have been derived from prior human infant CHD MR studies and neonatal mouse models of CHD that were collectively used to calculate to calculate a brain dysplasia score (BDS) that included assessment of subcortical structures including the olfactory bulb, the cerebellum and the hippocampus.

Methods

Neonates undergoing cardiac surgery for CHD were prospectively recruited from two large centers. Both pre- and postoperative MR brain scans were obtained. DTI in 42 directions was segmented into 90 regions using a neonatal brain template and three weighted methods. Clinical data collection included 18 patient-specific and 9 preoperative variables associated with preoperative scan and 6 intraoperative (e.g., cardiopulmonary bypass and deep hypothermic circulatory arrest times) and 12 postoperative variables associated with postoperative scan. We compared patient specific and preoperative clinical factors to network topology and tractography alterations on a preoperative neonatal brain MRI, and intra and postoperative clinical factors to network topology alterations on postoperative neonatal brain MRI. A composite BDS was created to score abnormal findings involving the cerebellar hemispheres and vermis, supratentorial extra-axial fluid, olfactory bulbs and sulci, hippocampus, choroid plexus, corpus callosum, and brainstem. The neuroimaging outcomes of this study included (1) connectome metrics: cost (number of connections) and global/nodal efficiency (network integration); (2) seed based tractography methods of fractional anisotropy (FA), radial diffusivity, and axial diffusivity. Statistics consisted of multiple regression with false discovery rate correction (FDR) comparing the clinical risk factors and BDS (including subcortical components) as predictors/exposures and the global connectome metrics, nodal efficiency, and seed based- tractography (FA, radial diffusivity, and axial diffusivity) as neuroimaging outcome measures.

Results

A total of 133 term neonates with complex CHD were prospectively enrolled and 110 had analyzable DTI. Multiple patient-specific factors including d-transposition of the great arteries (d-TGA) physiology and severity of impairment of fetal cerebral substrate delivery (i.e., how much the CHD lesion alters typical fetal circulation such that the highest oxygen and nutrient rich blood from the placenta are not directed toward the fetal brain) were predictive of preoperative reduced cost (p < 0.0073) and reduced global/nodal efficiency (p < 0.03). Cardiopulmonary bypass time predicted postoperative reduced cost (p < 0.04) and multiple postoperative factors [extracorporeal membrane oxygenation (ECMO), seizures and cardiopulmonary resuscitation (CPR)] were predictive of postoperative reduced cost and reduced global/nodal efficiency (p < 0.05). Anthropometric measurements (weight, length, and head size) predicted tractography outcomes. Total BDS was not predictive of brain network topology. However, key subcortical components of the BDS score did predict key global and nodal network topology: abnormalities of the cerebellum predicted reduced cost (p < 0.0417) and of the hippocampus predicted reduced global efficiency (p < 0.0126). All three subcortical structures predicted unique alterations of nodal efficiency (p < 0.05), including hippocampal abnormalities predicting widespread reduced nodal efficiency in all lobes of the brain, cerebellar abnormalities predicting increased prefrontal nodal efficiency, and olfactory bulb abnormalities predicting posterior parietal-occipital nodal efficiency.

Conclusion

Patient-specific (d-TGA anatomy, preoperative impairment of fetal cerebral substrate delivery) and postoperative (e.g., seizures, need for ECMO, or CPR) clinical factors were most predictive of diffuse postnatal microstructural dysmaturation in term CHD neonates. Anthropometric measurements (weight, length, and head size) predicted tractography outcomes. In contrast, subcortical components (cerebellum, hippocampus, olfactory) of a structurally based BDS (derived from CHD mouse mutants), predicted more localized and regional postnatal microstructural differences. Collectively, these findings suggest that brain DTI connectome and seed-based tractography are complementary techniques which may facilitate deciphering the mechanistic relative contribution of clinical and genetic risk factors related to poor neurodevelopmental outcomes in CHD.

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.

Prescription medication use after congenital heart surgery

BACKGROUND

Improvements in mortality after congenital heart surgery have necessitated a shift in focus to postoperative morbidity as an outcome measure. We examined late morbidity after congenital heart surgery based on prescription medication use.

METHODS

Between 1953 and 2009, 10,635 patients underwent congenital heart surgery at <15 years of age in Finland. We obtained 4 age-, sex-, birth-time, and hospital district-matched controls per patient. The Social Insurance Institution of Finland provided data on all prescription medications obtained between 1999 and 2012 by patients and controls. Patients were assigned one diagnosis based on a hierarchical list of cardiac defects and dichotomised into simple and severe groups. Medications were divided into short- and long-term based on indication. Follow-up started at the first operation and ended at death, emigration, or 31 December, 2012.

RESULTS

Totally, 8623 patients met inclusion criteria. Follow-up was 99.9%. In total, 8126 (94%) patients required prescription medications. Systemic anti-bacterials were the most common short-term prescriptions among patients (93%) and controls (88%). Patients required betablockers (simple hazard ratio 1.9, 95% confidence interval 1.7-2.1; severe hazard ratio 6.5, 95% confidence interval 5.3-8.1) and diuretics (simple hazard ratio 3.2, 95% CI 2.8-3.7; severe hazard ratio 38.8, 95% CI 27.5-54.7) more often than the general population. Both simple and severe defects required medication for cardiovascular, gastrointestinal, psychiatric, neurologic, metabolic, autoimmune, and infectious diseases more often than the general population.

CONCLUSIONS

The significant risk for postoperative cardiovascular and non-cardiovascular disease warrants close long-term follow-up after congenital heart surgery for all defects.

Evaluation and Management of Noncardiac Comorbidities in Children With Congenital Heart Disease

Outcomes for patients with neonatal heart disease are affected by numerous noncardiac and genetic factors. These can include neonatal concerns, such as prematurity and low birth weight, and congenital anomalies, such as airway, pulmonary, gastrointestinal, and genitourinary anomalies, and genetic syndromes. This section will serve as a summary of these issues and how they may affect the evaluation and management of a neonate with heart disease. These noncardiac factors are heavily influenced by conditions common to neonatologists, making a strong argument for multidisciplinary care with neonatologists, cardiologists, surgeons, anesthesiologists, and cardiovascular intensivists. Through this section and this project, we aim to facilitate a comprehensive approach to the care of neonates with congenital heart disease.

Optimizing Neurodevelopmental Outcomes in Neonates With Congenital Heart Disease

Neurodevelopmental impairment is a common and important long-term morbidity among infants with congenital heart disease (CHD). More than half of those with complex CHD will demonstrate some form of neurodevelopmental, neurocognitive, and/or psychosocial dysfunction requiring specialized care and impacting long-term quality of life. Preventing brain injury and treating long-term neurologic sequelae in this high-risk clinical population is imperative for improving neurodevelopmental and psychosocial outcomes. Thus, cardiac neurodevelopmental care is now at the forefront of clinical and research efforts. Initial research primarily focused on neurocritical care and operative strategies to mitigate brain injury. As the field has evolved, investigations have shifted to understanding the prenatal, genetic, and environmental contributions to impaired neurodevelopment. This article summarizes the recent literature detailing the brain abnormalities affecting neurodevelopment in children with CHD, the impact of genetics on neurodevelopmental outcomes, and the best practices for neonatal neurocritical care, focusing on developmental care and parental support as new areas of importance. A framework is also provided for the infrastructure and resources needed to support CHD families across the continuum of care settings.

Prevalence, Risk Factors, and Impact of Preoperative Seizures in Neonates With Congenital Heart Disease

PURPOSE

The purpose of this study was to assess the prevalence, risk factors, and impact of electrographic seizures in neonates with complex congenital heart disease before cardiac surgery.

METHODS

A cohort of 31 neonates with congenital heart disease monitored preoperatively with continuous video-EEG (cEEG) was first reviewed for electrographic seizure burden and EEG background abnormalities. Second, cEEG findings were correlated with brain MRI and 18-month outcomes.

RESULTS

Continuous video-EEG was recorded preoperatively for a median duration of 20.5 hours (range, 2.5-93.5 hours). The five neonates (16%; 95% confidence interval, 5.5% to 34%) with seizures detected on cEEG in the preoperative period had a diagnosis of transposition of the great arteries or similar physiology, detected in four of five postnatally. None of the 157 recorded electrographic seizures had a clinical correlate. The median time to first seizure was 65 minutes (range, 6-300 minutes) after cEEG hookup. The median maximum hourly seizure burden was 12.4 minutes (range, 7-23 minutes). Before the first electrographic seizure, a prolonged interburst interval (>10 seconds) was not associated with seizures (coefficient 1.2; 95% confidence interval, -1.1 to 3.6). MRI brain lesions were three times more common in neonates with seizures. Sharp wave transients on cEEG were associated with delayed opercular development.

CONCLUSIONS

In this cohort, preoperative electrographic seizures were common, were all subclinical, and were associated with MRI brain injury and postnatal diagnosis of transposition of the great arteries. The findings motivate further study of the mechanisms of preoperative brain injury, particularly among neonates with a postnatal diagnosis of transposition of the great arteries.

Age Difference of the Relationship Between Cerebral Oxygen Saturation and Physiological Parameters in Pediatric Cardiac Surgery with Cardiopulmonary Bypass: Analysis Using the Random-Effects Model

Recently, monitoring of cerebral oxygen saturation (ScO₂) has become widespread in pediatric cardiac surgery. Our previous study reported that mean blood pressure (mBP) was the major contributor to ScO₂ throughout cardiac surgery with cardiopulmonary bypass (CPB) in children weighing under 10 kg. We speculated that this result might be attributable to incomplete cerebral autoregulation in such young children. Accordingly, our hypothesis is that the relationship between ScO₂ and the physiological parameters may change according to the growth of the children. ScO₂ was measured with an INVOS 5100C (Somanetics, Troy, MI). Random-effects analysis was employed with ScO₂ as a dependent variable, and seven physiological parameters (mBP, central venous pressure, nasopharyngeal temperature, SaO₂, hematocrit, PaCO₂, and pH) were entered as independent covariates. The analysis was performed during the pre-CPB, CPB, and post-CPB periods by dividing the patients into two groups: infants (Infant Group) and children who were more than 1 year old (Child Group). The Infant and Child Groups consisted of 28 and 21 patients. In the random-effects analysis, mBP was the major contributor to ScO₂ during CPB in both groups. During the pre-CPB period, the effect of mBP was strongest in the Infant group. However, its effect was second to that of SaO₂ in the Child Group. During the post-CPB period, SaO₂ and mBP still affected ScO₂ in the Infant group. However, the dominant contributors were unclear in the Child Group. Cerebral autoregulation may be immature in infants. In addition, it may be impaired during CPB even after 1 year of age.

Association of Cerebrovascular Stability Index and Head Circumference Between Infants With and Without Congenital Heart Disease

Congenital heart disease (CHD) is a common birth defect in the United States. CHD infants are more likely to have smaller head circumference and neurodevelopmental delays; however, the cause is unknown. Altered cerebrovascular hemodynamics may contribute to neurologic abnormalities, such as smaller head circumference, thus we created a novel Cerebrovascular Stability Index (CSI), as a surrogate for cerebral autoregulation. We hypothesized that CHD infants would have an association between CSI and head circumference. We performed a prospective, longitudinal study in CHD infants and healthy controls. We measured CSI and head circumference at 4 time points (newborn, 3, 6, 9 months). We calculated CSI by subtracting the average 2-min sitting from supine cerebral oxygenation (rcSO₂) over three consecutive tilts (0-90°), then averaged the change score for each age. Linear regressions quantified the relationship between CSI and head circumference. We performed 177 assessments in total (80 healthy controls, 97 CHD infants). The average head circumference was smaller in CHD infants (39.2 cm) compared to healthy controls (41.6 cm) (p < 0.001) and head circumference increased by 0.27 cm as CSI improved in the sample (p = 0.04) overall when combining all time points. Similarly, head circumference increased by 0.32 cm as CSI improved among CHD infants (p = 0.04). We found CSI significantly associated with head circumference in our sample overall and CHD infants alone, which suggests that impaired CSI may affect brain size in CHD infants. Future studies are needed to better understand the mechanism of interaction between CSI and brain growth.

Practice variations for fetal and neonatal congenital heart disease within the Children's Hospitals Neonatal Consortium

BACKGROUND

Many aspects of care for fetuses and neonates with congenital heart disease (CHD) fall outside standard practice guidelines, leading to the potential for significant variation in clinical care for this vulnerable population.

METHODS

We conducted a cross-sectional survey of site sponsors of the Children's Hospitals Neonatal Consortium, a multicenter collaborative of 41 Level IV neonatal intensive care units to assess key areas of clinical practice variability for patients with fetal and neonatal CHD.

RESULTS

We received responses from 31 centers. Fetal consult services are shared by neonatology and pediatric cardiology at 70% of centers. Three centers (10%) routinely perform fetal magnetic resonance imaging (MRI) for women with pregnancies complicated by fetal CHD. Genetic testing for CHD patients is routine at 76% of centers. Preoperative brain MRI is standard practice at 5 centers (17%), while cerebral NIRS monitoring is regularly used at 14 centers (48%). Use of electroencephalogram (EEG) after major cardiac surgery is routine in 5 centers (17%). Neurodevelopmental follow-up programs are offered at 30 centers (97%).

CONCLUSIONS

Many aspects of fetal and neonatal CHD care are highly variable with evolving shared multidisciplinary models.

IMPACT

Many aspects of fetal and neonatal CHD care are highly variable. Genetic testing, placental examination, preoperative neuroimaging, and postoperative EEG monitoring carry a high yield of finding abnormalities in patients with CHD and these tests may contribute to more precise prognostication and improve care. Evidence-based standards for prenatal and postnatal CHD care may decrease inter-center variability.

Ketamine for Management of Neonatal and Pediatric Refractory Status Epilepticus

BACKGROUND AND OBJECTIVES

Few data are available regarding the use of anesthetic infusions for refractory status epilepticus (RSE) in children and neonates, and ketamine use is increasing despite limited data. We aimed to describe the impact of ketamine for RSE in children and neonates.

METHODS

Retrospective single-center cohort study of consecutive patients admitted to the intensive care units of a quaternary care children's hospital treated with ketamine infusion for RSE.

RESULTS

Sixty-nine patients were treated with a ketamine infusion for RSE. The median age at onset of RSE was 0.7 years (interquartile range 0.15-7.2), and the cohort included 13 (19%) neonates. Three patients (4%) had adverse events requiring intervention during or within 12 hours of ketamine administration, including hypertension in 2 patients and delirium in 1 patient. Ketamine infusion was followed by seizure termination in 32 patients (46%), seizure reduction in 19 patients (28%), and no change in 18 patients (26%).

DISCUSSION

Ketamine administration was associated with few adverse events, and seizures often terminated or improved after ketamine administration. Further data are needed comparing first-line and subsequent anesthetic medications for treatment of pediatric and neonatal RSE.

CLASSIFICATION OF EVIDENCE

This study provides Class IV evidence on the therapeutic utility of ketamine for treatment of RSE in children and neonates.

High-Risk Anatomic Subsets in Hypoplastic Left Heart Syndrome

Despite overall improvements in outcomes for patients with hypoplastic left heart syndrome, there remain anatomic features that can place these patients at higher risk throughout their treatment course. These include severe preoperative obstruction to pulmonary venous return, restrictive atrial septum, coronary fistulae, severe tricuspid regurgitation, smaller ascending aorta diameter (especially if <2 mm), and poor ventricular function. The risk of traditional staged palliation has led to the development of alternative strategies for such patients. To further improve the outcomes, we must continue to diligently examine and study anatomic details in HLHS patients.

Neurometabolic changes in neonates with congenital heart defects and their relation to neurodevelopmental outcome

BACKGROUND

Altered neurometabolite ratios in neonates undergoing cardiac surgery for congenital heart defects (CHD) may serve as a biomarker for altered brain development and neurodevelopment (ND).

METHODS

We analyzed single voxel 3T PRESS H¹-MRS data, acquired unilaterally in the left basal ganglia and white matter of 88 CHD neonates before and/or after neonatal cardiac surgery and 30 healthy controls. Metabolite ratios to Creatine (Cr) included glutamate (Glu/Cr), myo-Inositol (mI/Cr), glutamate and glutamine (Glx/Cr), and lactate (Lac/Cr). In addition, the developmental marker N-acetylaspartate to choline (NAA/Cho) was evaluated. All children underwent ND outcome testing using the Bayley Scales of Infant and Toddler Development Third Edition (BSID-III) at 1 year of age.

RESULTS

White matter NAA/Cho ratios were lower in CHD neonates compared to healthy controls (group beta estimate: -0.26, std. error 0.07, 95% CI: -0.40 - 0.13, p value <0.001, FDR corrected p value = 0.010). We found no correlation between pre- or postoperative white matter NAA/Cho with ND outcome while controlling for socioeconomic status and CHD diagnosis.

CONCLUSION

Reduced white matter NAA/Cho in CHD neonates undergoing cardiac surgery may reflect a delay in brain maturation. Further long-term MRS studies are needed to improve our understanding of the clinical impact of altered metabolites on brain development and outcome.

IMPACT

NAA/Cho was reduced in the white matter, but not the gray matter of CHD neonates compared to healthy controls. No correlation to the 1-year neurodevelopmental outcome (Bayley-III) was found. While the rapid change of NAA/Cho with age might make it a sensitive marker for a delay in brain maturation, the relationship to neurodevelopmental outcome requires further investigation.

Correlation of Cerebral Microdialysis with Non-Invasive Diffuse Optical Cerebral Hemodynamic Monitoring during Deep Hypothermic Cardiopulmonary Bypass

Neonates undergoing cardiac surgery involving aortic arch reconstruction are at an increased risk for hypoxic-ischemic brain injury. Deep hypothermia is utilized to help mitigate this risk when periods of circulatory arrest are needed for surgical repair. Here, we investigate correlations between non-invasive optical neuromonitoring of cerebral hemodynamics, which has recently shown promise for the prediction of postoperative white matter injury in this patient population, and invasive cerebral microdialysis biomarkers. We compared cerebral tissue oxygen saturation (StO₂), relative total hemoglobin concentration (rTHC), and relative cerebral blood flow (rCBF) measured by optics against the microdialysis biomarkers of metabolic stress and injury (lactate–pyruvate ratio (LPR) and glycerol) in neonatal swine models of deep hypothermic cardiopulmonary bypass (DHCPB), selective antegrade cerebral perfusion (SACP), and deep hypothermic circulatory arrest (DHCA). All three optical parameters were negatively correlated with LPR and glycerol in DHCA animals. Elevation of LPR was found to precede the elevation of glycerol by 30–60 min. From these data, thresholds for the detection of hypoxic-ischemia-associated cerebral metabolic distress and neurological injury are suggested. In total, this work provides insight into the timing and mechanisms of neurological injury following hypoxic-ischemia and reports a quantitative relationship between hypoxic-ischemia severity and neurological injury that may inform DHCA management.

"The Mental Health Piece is Huge": perspectives on developing a prenatal maternal psychological intervention for congenital heart disease

OBJECTIVES

Women carrying a fetus diagnosed with congenital heart disease often experience significant distress because of their medical diagnosis. Given the well-documented impact associated with elevated prenatal stress and critical importance of developing targeted interventions, this study aims to examine stressors, coping and resilience resources, and mental health treatment preferences in pregnant women receiving a congenital heart disease diagnosis to inform the development of a psychological intervention to reduce maternal distress prenatally.

METHODS

Three groups of participants were included consisting of two pregnant women carrying a fetus with congenital heart disease, five women of children (4-16 months) with congenital heart disease, and five paediatric cardiology medical providers. Responses were gathered via semi-structured interviews and analysed using qualitative thematic analysis.

RESULTS

Information regarding four broad areas were analysed of emotional distress during pregnancy; experience of initial diagnosis; coping and resilience; and perspectives on a mental health intervention in pregnancy. Anxiety regarding baby's future, guilt following diagnosis, and various coping strategies emerged as primary themes among the participant sample. Medical staff corroborated mothers' heightened anxiety and viewed a psychotherapeutic intervention during the prenatal period as essential and complimentary to standard of care.

CONCLUSION

We identified salient themes and preferred components for a future psychological intervention delivered prenatally.

PRACTICE IMPLICATIONS

Patients' and providers' perspectives regarding the nature of maternal distress, resilience and treatment preferences can inform the development of interventions to support the emotional well-being of pregnant women carrying a fetus with congenital heart disease to optimise care and potentially improve outcomes for fetal brain development.

Impact of Comorbid Prematurity and Congenital Anomalies: A Review

Preterm infants are more likely to be born with congenital anomalies than those who are born at full-term. Conversely, neonates born with congenital anomalies are also more likely to be born preterm than those without congenital anomalies. Moreover, the comorbid impact of prematurity and congenital anomalies is more than cumulative. Multiple common factors increase the risk of brain injury and neurodevelopmental impairment in both preterm babies and those born with congenital anomalies. These include prolonged hospital length of stay, feeding difficulties, nutritional deficits, pain exposure and administration of medications including sedatives and analgesics. Congenital heart disease provides a well-studied example of the impact of comorbid disease with prematurity. Impaired brain growth and maturity is well described in the third trimester in this population; the immature brain is subsequently more vulnerable to further injury. There is a colinear relationship between degree of prematurity and outcome both in terms of mortality and neurological morbidity. Both prematurity and relative brain immaturity independently increase the risk of subsequent neurodevelopmental impairment in infants with CHD. Non-cardiac surgery also poses a greater risk to preterm infants despite the expectation of normal in utero brain growth. Esophageal atresia, diaphragmatic hernia and abdominal wall defects provide examples of congenital anomalies which have been shown to have poorer neurodevelopmental outcomes in the face of prematurity, with associated increased surgical complexity, higher relative cumulative doses of medications, longer hospital and intensive care stay and increased rates of feeding difficulties, compared with infants who experience either prematurity or congenital anomalies alone.

Prematurity and Congenital Heart Disease: A Contemporary Review

Congenital heart disease (CHD) is the most commonly reported birth defect in newborns. Neonates with CHD are more likely to be born prematurely, and a higher proportion of preterm neonates have CHD than their term counterparts. The implications of preterm birth on the cardiac and noncardiac organ systems are vast and require special management considerations. The feasibility of surgical interventions in preterm neonates is frequently limited by patient size and delicacy of immature cardiac tissues. Thus, special care must be taken when considering the appropriate timing and type of cardiac intervention. Despite improvements in neonatal cardiac surgical outcomes, preterm and early term gestational ages and low birthweight remain important risk factors for in-hospital mortality. Understanding the risks of early delivery of neonates with prenatally diagnosed CHD may help guide perioperative management in neonates who are born preterm. In this review, we will describe the risks and benefits of early delivery, postnatal cardiac and noncardiac evaluation and management, surgical considerations, overall outcomes, and future directions regarding optimization of perinatal evaluation and management of fetuses and preterm and early term neonates with CHD.

Impact of Congenital Heart Defects on the Developing Brain

OBJECTIVES

Congenital heart defects (CHD) are responsible for neurodevelopmental delays that were initially attributed to brain injury resulting from cardiac surgery. However, prenatal imaging have shown that brain anomalies are present at birth. The aim of this study was to assess in utero brain injuries before birth in fetuses/neonates with congenital cardiopathies.

METHODS

A complete autopsy evaluation with detailed study of the cardiopathy and neuropathological study was performed in 40 fetuses/neonates. Syndromic congenital cardiopathies were excluded because of the potential other causes of brain injury. The patients were classified into two groups according to their term at death.

RESULTS

Statistical analyses indicated the mean brain weight was not significantly different between subjects with different morphological types of congenital cardiopathies. However, the brain weight was at or below the fifth percentile in most third-trimester subjects compared to normal brain weight in second-trimester subjects. Low brain weight in third-trimester subjects was also associated with frequent lesions similar to those described in preterm infants, with a particular involvement of white matter and its components.

CONCLUSIONS

These observations allowed us to establish the timing and impact of prenatal neuropathological lesions on brain development, and to correlate them with imaging data reported in the literature.

Altered Cerebral Microstructure in Adults With Atrial Septal Defect and Ventricular Septal Defect Repaired in Childhood

Background

Delayed brain development, brain injury, and neurodevelopmental disabilities are commonly observed in infants operated for complex congenital heart defect. Our previous findings of poorer neurodevelopmental outcomes in individuals operated for simple congenital heart defects calls for further etiological clarification. Hence, we examined the microstructural tissue composition in cerebral cortex and subcortical structures in comparison to healthy controls and whether differences were associated with neurodevelopmental outcomes.

Methods and Results

Adults (n=62) who underwent surgical closure of an atrial septal defect (n=33) or a ventricular septal defect (n=29) in childhood and a group of healthy, matched controls (n=38) were enrolled. Brain diffusional kurtosis imaging and neuropsychological assessment were performed. Cortical and subcortical tissue microstructure were assessed using mean kurtosis tensor and mean diffusivity and compared between groups and tested for associations with neuropsychological outcomes. Alterations in microstructural tissue composition were found in the parietal, temporal, and occipital lobes in the congenital heart defects, with distinct mean kurtosis tensor cluster‐specific changes in the right visual cortex (pericalcarine gyrus, P=0.002; occipital part of fusiform and lingual gyri, P=0.019). Altered microstructural tissue composition in the subcortical structures was uncovered in atrial septal defects but not in ventricular septal defects. Associations were found between altered cerebral microstructure and social recognition and executive function.

Conclusions

Children operated for simple congenital heart defects demonstrated altered microstructural tissue composition in the cerebral cortex and subcortical structures during adulthood when compared with healthy peers. Alterations in cerebral microstructural tissue composition were associated with poorer neuropsychological performance.

Registration

URL: https://www.clinicaltrials.gov; Unique identifier: NCT03871881.

In infants with congenital heart disease autonomic dysfunction is associated with pre-operative brain injury

BACKGROUND

Brain injury is a serious and common complication of critical congenital heart disease (CHD). Impaired autonomic development (assessed by heart rate variability (HRV)) is associated with brain injury in other high-risk neonatal populations.

OBJECTIVE

To determine whether impaired early neonatal HRV is associated with pre-operative brain injury in CHD.

METHODS

In infants with critical CHD, we evaluated HRV during the first 24 h of cardiac ICU (CICU) admission using time-domain (RMS 1, RMS 2, and alpha 1) and frequency-domain metrics (LF, nLF, HF, nHF). Pre-operative brain magnetic resonance imaging (MRI) was scored for injury using an established system. Spearman's correlation coefficient was used to determine the association between HRV and pre-operative brain injury.

RESULTS

We enrolled 34 infants with median birth gestational age of 38.8 weeks (IQR 38.1-39.1). Median postnatal age at pre-operative brain MRI was 2 days (IQR 1-3 days). Thirteen infants had MRI evidence of brain injury. RMS 1 and RMS 2 were inversely correlated with pre-operative brain injury.

CONCLUSIONS

Time-domain metrics of autonomic function measured within the first 24 h of admission to the CICU are associated with pre-operative brain injury, and may perform better than frequency-domain metrics under non-stationary conditions such as critical illness.

IMPACT

Autonomic dysfunction, measured by heart rate variability (HRV), in early transition is associated with pre-operative brain injury in neonates with critical congenital heart disease. These data extend our earlier findings by providing further evidence for (i) autonomic dysfunction in infants with CHD, and (ii) an association between autonomic dysfunction and brain injury in critically ill neonates. These data support the notion that further investigation of HRV as a biomarker for brain injury risk is warranted in infants with critical CHD.

Chronic hypoxemia induces mitochondrial respiratory complex gene expression in the fetal sheep brain

Objective

The molecular pathways underlying hypoxemia-induced alterations in neurodevelopment of infants with congenital heart disease have not been delineated. We used transcriptome analysis to investigate differential gene expression induced by hypoxemia in an ovine artificial-womb model.

Methods

Mid-gestation fetal sheep (median [interquartile range] 109 [107-112] days' gestation) were cannulated via the umbilical vessels, attached to a pumpless, low-resistance oxygenator circuit, and incubated in a sterile, fluid environment for 22 [21-23] days. Fetuses were maintained with an oxygen delivery of 20-25 mL/kg/min (normoxemia, n = 3) or 14-16 mL/kg/min (hypoxemia, n = 4). Transcriptional profiling by RNA sequencing was carried out on left frontal brains and hypoxemia-regulated genes were identified by differential gene expression analysis.

Results

A total of 228 genes whose expression was up or down regulated by ≥1.5-fold (false discovery rate ≤0.05) were identified. The majority of these genes were induced in hypoxemic animals compared to normoxemic controls, and functional enrichment analysis identified respiratory electron transport as a pathway strongly upregulated in the brain during chronic hypoxemia. Further examination of hypoxemia-induced genes showed robust induction of all 7 subunits of the mitochondrial NADH:ubiquinone oxidoreductase (complex I). Other hypoxemia-induced genes included cytochrome B, a component of complex III, and ATP6, ATP8, both of which are components of complex V.

Conclusions

Chronic fetal hypoxemia leads to upregulation of multiple mitochondrial respiratory complex genes critical for energy production and reactive oxygen species generation, including complex I. These data provide valuable insight into potential pathways involved in chronic hypoxemia-induced neuropathology and offers potential therapeutic targets for fetal neuroprotection in fetuses with congenital heart defects.

Quality of life and other patient-reported outcomes across the lifespan among people with Fontan palliation

Traditional congenital heart disease (CHD) outcomes include mortality (survival to adulthood and life expectancy) as well as cardiac and non-cardiac morbidity. Strategies to identify and manage sequelae have primarily focused on objective data obtained though invasive and non-invasive diagnostic approaches. In contrast, patient-reported outcomes (PROs) provide subjective information, using standardized measures, about patients' health and wellbeing as reported directly by patients, without interpretation, interference, or assumptions made by clinicians or others. Selection of PRO measures entails thoughtful consideration of who the individuals being surveyed are, why assessment is occurring (e.g., what are the domains of interest; clinical vs. research), and what processes are in place for acquisition, administration, interpretation, and response. In this review, we focus on three domains of PROs for pediatric and adult patients with Fontan physiology: physical health status, psychological functioning, and quality of life (QOL). Infants, children, adolescents, and adults with CHD face a spectrum of challenges that may influence PROs across the lifespan. In general, patients with Fontan palliation tend to have lower physical health status, experience more psychological distress, and have equivalent or reduced QOL compared to healthy peers. Herein, we provide an overview of PROs among people with Fontan circulation as a group, yet simultaneously emphasize that the optimal way to understand the experiences of any individual patient is to ask and listen. We also offer clinical and research initiatives to improve the adoption and utility of PROs in CHD settings, which demonstrate commitment to capturing, understanding, and responding to the patient voice.

Pre-eclampsia is associated with increased neurodevelopmental disorders in children with congenital heart disease

AIMS

Our primary aim was to examine whether exposure to pre-eclampsia increases the risk of neurodevelopmental disorders in children born with congenital heart disease (CHD). Our secondary aim was to evaluate whether CHD and pre-eclampsia may act in synergy and potentiate this risk.

METHOD AND RESULTS

Using population-based registries, we included all Danish children born with CHD between 1994 and 2017. Non-singletons and children born with a syndrome were excluded. Neurodevelopmental disorders including attention-deficit/hyperactivity disorder, autism spectrum disorders, and tic disorders were identified with the use of the 10th edition of International Classification of Disease (ICD-10) codes DF80-DF98. Using Cox proportional hazard regression, we estimated the risk of neurodevelopmental disorders in children with CHD exposed to pre-eclampsia compared with those with CHD not exposed to pre-eclampsia. The population consisted of 11 449 children born with CHD. Children exposed to pre-eclampsia had an increased risk of neurodevelopmental disorders, hazard ratio: 1.84 (95% confidence interval: 1.39-2.42). Furthermore, a comparison cohort of 113 713 children with no CHD diagnoses were included. Using cumulative incidence analyses with death as competing risk, we compared the risk of neurodevelopmental disorders if exposed to pre-eclampsia among children with CHD and children without CHD. Exposure to pre-eclampsia drastically increased the cumulative incidence of neurodevelopmental disorders in children born with CHD.

CONCLUSION

Exposure to pre-eclampsia is associated with increased risk of neurodevelopmental disorders in children born with CHD. CHD and pre-eclampsia may act in synergy and potentiate this effect. Clinicians should therefore be especially attentive to neurodevelopmental problems in this vulnerable subgroup.

Chronic foetal hypoxaemia does not cause elevation of serum markers of brain injury

OBJECTIVES

The objective of this study was to investigate changes in serum biomarkers of acute brain injury, including white matter and astrocyte injury during chronic foetal hypoxaemia. We have previously shown histopathological changes in myelination and neuronal density in fetuses with chronic foetal hypoxaemia at a level consistent with CHD.

METHODS

Mid-gestation foetal sheep (110 ± 3 days gestation) were cannulated and attached to a pumpless, low-resistance oxygenator circuit, and incubated in a sterile fluid environment mimicking the intrauterine environment. Fetuses were maintained with an oxygen delivery of 20-25 ml/kg/min (normoxemia) or 14-16 ml/kg/min (hypoxaemia). Myelin Basic Protein and Glial Fibrillary Acidic Protein serum levels in the two groups were assessed by ELISA at baseline and at 7, 14, and 21 days of support.

RESULTS

Based on overlapping 95% confidence intervals, there were no statistically significant differences in either Myelin Basic Protein or Glial Fibrillary Acidic Protein serum levels between the normoxemic and hypoxemic groups, at any time point. No statistically significant correlations were observed between oxygen delivery and levels of Myelin Basic Protein and Glial Fibrillary Acidic Protein.

CONCLUSION

Chronic foetal hypoxaemia during mid-gestation is not associated with elevated serum levels of acute white matter (Myelin Basic Protein) or astrocyte injury (Glial Fibrillary Acidic Protein), in this model. In conjunction with our previously reported findings, our data support the hypothesis that the brain dysmaturity with impaired myelination found in fetuses with chronic hypoxaemia is caused by disruption of normal developmental pathways rather than by direct cellular injury.

Genetic mouse models of autism spectrum disorder present subtle heterogenous cardiac abnormalities

Autism spectrum disorder (ASD) and congenital heart disease (CHD) are linked on a functional and genetic level. Most work has investigated CHD‐related neurodevelopmental abnormalities. Cardiac abnormalities in ASD have been less studied. We investigated the prevalence of cardiac comorbidities relative to ASD genetic contributors. Using high frequency ultrasound imaging, we screened 9 ASD‐related genetic mouse models (Arid1b^(+/−), Chd8^(+/−), 16p11.2 (deletion), Sgsh^(+/−), Sgsh^(−/−), Shank3 Δexon 4–9^(+/−), Shank3 Δexon 4–9^(−/−), Fmr1^(−/−), Vps13b^(+/−)), and pooled wild‐type littermates (WTs). We measured heart rate (HR), aorta diameter (AoD), thickness and thickening of the left‐ventricular (LV) anterior and posterior walls, LV chamber diameter, fractional shortening, stroke volume and cardiac output, mitral inflow Peak E and A velocity ratio, ascending aorta velocity time integral (VTI). Mutant groups presented small‐scale alterations in cardiac structure and function compared to WTs (LV anterior wall thickness and thickening, chamber diameter and fractional shortening, HR). A greater number of significant differences was observed among mutant groups than between mutant groups and WTs. Mutant groups differed primarily in structural measures (LV chamber diameter and anterior wall thickness, HR, AoD). The mutant groups with most differences to WTs were 16p11.2 (deletion), Fmr1^(−/−), Arid1b^(+/−). The mutant groups with most differences from other mutant groups were 16p11.2 (deletion), Sgsh^(+/−), Fmr1^(−/−). Our results recapitulate the associated clinical findings. The characteristic ASD heterogeneity was recapitulated in the cardiac phenotype. The type of abnormal measures (morphological, functional) can highlight common underlying mechanisms. Clinically, knowledge of cardiac abnormalities in ASD can be essential as even non‐lethal abnormalities impact normal development.

Altered myelination in youth born with congenital heart disease

Brain injury and dysmaturation is common in fetuses and neonates with congenital heart disease (CHD) and is hypothesized to result in persistent myelination deficits. This study aimed to quantify and compare myelin content in vivo between youth born with CHD and healthy controls. Youth aged 16 to 24 years born with CHD and healthy age‐ and sex‐matched controls underwent brain magnetic resonance imaging including multicomponent driven equilibrium single pulse observation of T₁ and T₂ (mcDESPOT). Average myelin water fraction (MWF) values for 33 white matter tracts, as well as a summary measure of average white matter MWF, the White Matter Myelination Index, were calculated and compared between groups. Tract‐average MWF was lower throughout the corpus callosum and in many bilateral association tracts and left hemispheric projection tracts in youth with CHD (N = 44) as compared to controls (N = 45). The White Matter Myelination Index was also lower in the CHD group. As such, this study provides specific evidence of widespread myelination deficits in youth with CHD, likely representing a long‐lasting consequence of early‐life brain dysmaturation in this population. This deficient myelination may underlie the frequent neurodevelopmental impairments experienced by CHD survivors and could eventually serve as a biomarker of neuropsychological function.

Fetal Brain Volume Predicts Neurodevelopment in Congenital Heart Disease

BACKGROUND

Neurodevelopmental impairment is common in children with congenital heart disease (CHD), but postnatal variables explain only 30% of the variance in outcomes. To explore whether the antecedents for neurodevelopmental disabilities might begin in utero, we analyzed whether fetal brain volume predicted subsequent neurodevelopmental outcome in children with CHD.

METHODS

Fetuses with isolated CHD and sociodemographically comparable healthy control fetuses underwent fetal brain magnetic resonance imaging and 2-year neurodevelopmental evaluation with the Bayley Scales of Infant and Toddler Development, Third Edition (Bayley-III) and the Adaptive Behavior Assessment System, Third Edition (ABAS-3). Hierarchical regression evaluated potential predictors of Bayley-III and ABAS-3 outcomes in the CHD group, including fetal total brain volume adjusted for gestational age and sex, sociodemographic characteristics, birth measures, and medical history.

RESULTS

The CHD group (n=52) had lower Bayley-III cognitive, language, and motor scores than the control group (n=26), but fetal brain volumes were similar. Within the CHD group, larger fetal total brain volume correlated with higher Bayley-III cognitive, language, and motor scores and ABAS-3 adaptive functioning scores (r=0.32-0.47; all P<0.05), but this was not noted in the control group. Fetal brain volume predicted 10% to 21% of the variance in neurodevelopmental outcome measures in univariate analyses. Multivariable models that also included social class and postnatal factors explained 18% to 45% of the variance in outcome, depending on developmental domain. Moreover, in final multivariable models, fetal brain volume was the most consistent predictor of neurodevelopmental outcome across domains.

CONCLUSIONS

Small fetal brain volume is a strong independent predictor of 2-year neurodevelopmental outcomes and may be an important imaging biomarker of future neurodevelopmental risk in CHD. Future studies are needed to support this hypothesis. Our findings support inclusion of fetal brain volume in risk stratification models and as a possible outcome in fetal neuroprotective intervention studies.

Screening and Evaluation of Neurodevelopmental Impairments in Infants Under 6 Months of Age with Congenital Heart Disease

Clinical evaluation of neurodevelopmental impairments before 6 months of age is needed in congenital heart disease (CHD) to promote early referral to developmental interventions. The objective was to identify the risk of cerebral palsy (CP) and to compare neurodevelopment outcomes in infants with and without CHD. In a longitudinal study, 30 infants with CHD and 15 infants without CHD were assessed at 1 month, 3 months, and 6 months of age. Included measures were General Movement Assessment (GMA), Test of Infant Motor Performance (TIMP) and the Bayley Scale of Infant Development, third edition (Bayley-III), selected to identify the risk of CP, document neurodevelopmental impairments and infants' eligibility for early intervention services. Abnormal GMA categories were found in the CHD group where 48% had poor repertoire and 15% were at high risk of CP. At 3 months of age, CHD group had significantly lower TIMP scores compared to infants without CHD [t(41) = 6.57, p = 0.01]. All infants in the study had higher Bayley-III scores at 6 months than at 3 months of age. Infants with CHD had lower gross motor, fine motor and cognitive Bayley-III scores compared to their peers without CHD. Over time infants without CHD outperformed the CHD group in the gross motor skills [F_(1,41) = 11.76, p = .001]. Higher prevalence of abnormal GMs, lower TIMP and Bayley-III were found in infants with single ventricle physiology compared to two-ventricle physiology. The risk of CP exists in infants with CHD, and these infants have worse outcomes compared to their peers without CHD. These differences are intensified in the single ventricle population.Clinical Trial Registration National Institute of Health, Unique identifier: NCT03104751; Date of registration-April 7, 2017.

Characteristics of Neonates with Cardiopulmonary Disease Who Experience Seizures: A Multicenter Study

OBJECTIVE

To compare key seizure and outcome characteristics between neonates with and without cardiopulmonary disease.

STUDY DESIGN

The Neonatal Seizure Registry is a multicenter, prospectively acquired cohort of neonates with clinical or electroencephalographic (EEG)-confirmed seizures. Cardiopulmonary disease was defined as congenital heart disease, congenital diaphragmatic hernia, and exposure to extracorporeal membrane oxygenation. We assessed continuous EEG monitoring strategy, seizure characteristics, seizure management, and outcomes for neonates with and without cardiopulmonary disease.

RESULTS

We evaluated 83 neonates with cardiopulmonary disease and 271 neonates without cardiopulmonary disease. Neonates with cardiopulmonary disease were more likely to have EEG-only seizures (40% vs 21%, P < .001) and experience their first seizure later than those without cardiopulmonary disease (174 vs 21 hours of age, P < .001), but they had similar seizure exposure (many-recurrent electrographic seizures 39% vs 43%, P = .27). Phenobarbital was the primary initial antiseizure medication for both groups (90%), and both groups had similarly high rates of incomplete response to initial antiseizure medication administration (66% vs 68%, P = .75). Neonates with cardiopulmonary disease were discharged from the hospital later (hazard ratio 0.34, 95% CI 0.25-0.45, P < .001), although rates of in-hospital mortality were similar between the groups (hazard ratio 1.13, 95% CI 0.66-1.94, P = .64).

CONCLUSION

Neonates with and without cardiopulmonary disease had a similarly high seizure exposure, but neonates with cardiopulmonary disease were more likely to experience EEG-only seizures and had seizure onset later in the clinical course. Phenobarbital was the most common seizure treatment, but seizures were often refractory to initial antiseizure medication. These data support guidelines recommending continuous EEG in neonates with cardiopulmonary disease and indicate a need for optimized therapeutic strategies.

Corpus callosum size by neurosonography in fetuses with congenital heart defect and relationship with expected pattern of brain oxygen supply

OBJECTIVE

To evaluate corpus callosum (CC) size by neurosonography (NSG) in fetuses with an isolated major congenital heart defect (CHD) and explore the association of CC size with the expected pattern of in-utero oxygen supply to the brain.

METHODS

A total of 56 fetuses with postnatally confirmed isolated major CHD and 56 gestational-age-matched controls were included. Fetuses with CHD were stratified into two categories according to the main expected pattern of cerebral arterial oxygen supply: Class A, moderately to severely reduced oxygen supply (left outflow tract obstruction and transposition of the great arteries) and Class B, near normal or mildly impaired oxygenated blood supply to the brain (other CHD). Transvaginal NSG was performed at 32-36 weeks in all fetuses to evaluate CC length, CC total area and areas of CC subdivisions in the midsagittal plane.

RESULTS

CHD fetuses had a significantly smaller CC area as compared to controls (7.91 ± 1.30 vs 9.01 ± 1.44 mm² ; P < 0.001), which was more pronounced in the most posterior part of the CC. There was a significant linear trend for reduced CC total area across the three clinical groups, with CHD Class-A cases showing more prominent changes (controls, 9.01 ± 1.44 vs CHD Class B, 8.18 ± 1.21 vs CHD Class A, 7.53 ± 1.33 mm² ; P < 0.05).

CONCLUSIONS

Fetuses with major CHD had a smaller CC compared with controls, and the difference was more marked in the CHD subgroup with expected poorer brain oxygenation. Sonographic CC size could be a clinically feasible marker of abnormal white matter development in CHD. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

Are outcomes in congenital cardiac surgery better than ever?

BACKGROUND AND AIM OF THE STUDY

Congenital heart disease is the most common congenital defect among infants born in the United States. Within the first year of life, 1 in 4 of these infants will need surgery. Only one generation removed from an overall mortality of 14%, many changes have been introduced into the field. Have these changes measurably improved outcomes?

METHODS

The literature search was conducted through PubMed MEDLINE and Google Scholar from inception to October 31, 2021. Ultimately, 78 publications were chosen for inclusion.

RESULTS

The outcome of overall mortality has experienced continuous improvements in the modern era of the specialty despite the performance of more technically demanding surgeries on patients with complex comorbidities. This modality does not account for case-mix, however. In turn, clinical outcomes have not been consistent from center to center. Furthermore, variation in practice between institutions has also been documented. A recurring theme in the literature is a movement toward standardization and universalization. Examples include mortality risk-stratification that has allowed direct comparison of outcomes between programs and improved definitions of morbidities which provide an enhanced framework for diagnosis and management.

CONCLUSIONS

Overall mortality is now below 3%, which suggests that more patients are surviving their interventions than in any previous era in congenital cardiac surgery. Focus has transitioned from survival to improving the quality of life in the survivors by decreasing the incidence of morbidity and associated long-term effects. With the transformation toward standardization and interinstitutional collaboration, future advancements are expected.

Neurodevelopmental and functional outcome in hypoplastic left heart syndrome after Hybrid procedure as stage I

BACKGROUND

Patients with hypoplastic left heart syndrome (HLHS) undergoing staged palliation until Fontan procedure are at risk for impaired neurodevelopmental (ND) outcome. The Hybrid procedure with bilateral pulmonary artery banding, ductal stenting, and balloon atrioseptostomy may offer a less invasive stage I procedure compared to the Norwood stage I procedure avoiding early neonatal cardiopulmonary bypass (CPB) surgery. Despite altered fetal cerebral hemodynamics, the type of stage I procedure may be a covariate influencing ND outcome and functional outcome may also be altered due to postponing neonatal CPB surgery. Within this review, we analyzed ND outcome as well as functional outcome after Hybrid procedure as stage I procedure.

METHODS

The review analyzed original publications (OPs) published before March 15, 2022, identified by Cochrane, EMBASE, OVID, Scopus, and Web of science. An OP was included if short-to-long-term neurodevelopment outcome, brain development, somatic, and cardiac outcome in patients for HLHS and variants treated by Hybrid procedure were analyzed. In addition to database searches, we reviewed all references of the analyzed OP to obtain a comprehensive list of available studies. The author, year of publication, demographic characteristics of study population, study design (prospective or retrospective), study assessment, and main findings were summarized.

RESULTS

Twenty-one OPs were included with data of patients with ND outcome and functional cardiac outcome. Overall, there is an impaired mid-term ND outcome in patients with Hybrid procedure as stage I for HLHS. Only slight differences between stage I procedures (Hybrid vs. Norwood) in two comparing studies have been determined affecting right ventricular remodeling, short- and mid-term ND outcome, reduced brain growth until two years of age, sufficient quality of life, and altered hemodynamics influencing brain volumes and cerebral perfusion pattern.

CONCLUSIONS

Despite some minor differences regarding the mid-term follow-up in patients with HLHS comparing Hybrid vs. Norwood procedure, its impact on ND outcome seems rather low. This may be explained by the large number of covariates as well as the small study populations and the different selection criteria for patients undergoing Hybrid or Norwood procedure as stage I.

Neurodevelopmental and Mental Health Outcomes in Patients With Fontan Circulation: A State-of-the-Art Review

Children, adolescents and adults living with Fontan circulation face numerous neurological and developmental challenges. As the population with complex CHD increases thanks to outstanding improvement in medical and surgical care, the long-term developmental and mental health sequelae have become a public health priority in pediatric and congenital cardiology. Many patients with a Fontan circulation experience difficulty in areas of cognition related to attention and executive functioning, visual spatial reasoning and psychosocial development. They are also at high risk for mental health morbidities, particularly anxiety disorders and depression. Several hemodynamic risk factors, beginning during the fetal period, may influence outcomes and yield to abnormal brain growth and development. Brain injury such as white matter lesions, stroke or hemorrhage can occur before, during, or after surgery. Other sociodemographic and surgical risk factors such as multiple catheterizations and surgeries and prolonged hospital stay play a detrimental role in patients' neurodevelopmental prognosis. Prevention and intervention to optimize long-term outcomes are critical in the care of this vulnerable population with complex CHD.

Relationships Between Regional Cerebral Blood Flow and Neurocognitive Outcomes in Children and Adolescents With Congenital Heart Disease

To identify regional cerebral blood flow (rCBF) alterations in children and adolescents with congenital heart disease (CHD) in relation to neurocognitive outcomes using a nonbiased data-driven approach. This is a prospective, observational study of children and adolescents with CHD without brain injury and healthy controls using pseudo-continuous arterial spin labeling (pCASL) MRI. Quantitative rCBF was compared between participants with CHD and healthy controls using a voxelwise data-driven method. Mediation analysis was then performed on a voxelwise basis, with the grouping variable as the independent variable, neurocognitive outcomes (from the NIH Toolbox Cognitive Battery) as the dependent variables, and rCBF as the mediator. After motion correction, a total of 80 studies were analyzable (27 for patients with CHD, 53 for controls). We found steeper age-related decline in rCBF among those with CHD compared to normal controls in the insula/ventromedial prefrontal regions (salience network) and the dorsal anterior cingulate and precuneus/posterior cingulate (default mode network), and posterior parietal/dorsolateral prefrontal (central executive network) (FWE-corrected P< 0.05). The reduced rCBF in the default mode/salience network was found to mediate poorer performance on an index of crystallized cognition from the NIH Toolbox Cognitive Battery in those with CHD compared to controls. In contrast, reduced rCBF in the central executive network/salience network mediated reduced deficits in fluid cognition among patients with CHD compared to controls. Regional cerebral blood flow alterations mediate domain-specific differences in cognitive performance in children and adolescents with CHD compared to healthy controls, independent of injury, and are likely related to brain and cognitive reserve mechanisms. Further research is needed to evaluate the potential of interventions in CHD targeting regional cerebral blood flow across lifespan.

Neuroplacentology in congenital heart disease: placental connections to neurodevelopmental outcomes

Children with congenital heart disease (CHD) are living longer due to effective medical and surgical management. However, the majority have neurodevelopmental delays or disorders. The role of the placenta in fetal brain development is unclear and is the focus of an emerging field known as neuroplacentology. In this review, we summarize neurodevelopmental outcomes in CHD and their brain imaging correlates both in utero and postnatally. We review differences in the structure and function of the placenta in pregnancies complicated by fetal CHD and introduce the concept of a placental inefficiency phenotype that occurs in severe forms of fetal CHD, characterized by a myriad of pathologies. We propose that in CHD placental dysfunction contributes to decreased fetal cerebral oxygen delivery resulting in poor brain growth, brain abnormalities, and impaired neurodevelopment. We conclude the review with key areas for future research in neuroplacentology in the fetal CHD population, including (1) differences in structure and function of the CHD placenta, (2) modifiable and nonmodifiable factors that impact the hemodynamic balance between placental and cerebral circulations, (3) interventions to improve placental function and protect brain development in utero, and (4) the role of genetic and epigenetic influences on the placenta-heart-brain connection. IMPACT: Neuroplacentology seeks to understand placental connections to fetal brain development. In fetuses with CHD, brain growth abnormalities begin in utero. Placental microstructure as well as perfusion and function are abnormal in fetal CHD.

Double Jeopardy: Prematurity and Congenital Heart Disease-What's Known and Why It's Important

This article is based on a composite of talks presented during the Double Jeopardy: Prematurity and Congenital Heart Disease Plenary Session at NeoHeart 2020, a global virtual conference.Prematurity and low weight remain significant risk factors for mortality after neonatal cardiac surgery despite a steady increase in survival. Newer and lower weight thresholds for operability are constantly generated as surgeons gather proficiency, technical mastery, and experience in performing complex procedures on extremely small infants. The relationship between birth weight and survival after cardiac surgery is nonlinear with 2 kilograms (kg) being an inflection point below which marked decline in survival occurs.The prevalence of congenital heart disease (CHD) in premature infants is more than twice that in term born infants. Increased risk of preterm birth in infants with CHD is most commonly due to spontaneous preterm birth and remains poorly understood.Advances in Neonatal-Perinatal medicine have led to a marked improvement in survival of neonates born prematurely over the last several decades. However, the risk of severe morbidities including retinopathy of prematurity, intraventricular hemorrhage, bronchopulmonary dysplasia and necrotizing enterocolitis remains significant in extremely low birth weight infants. Premature infants with CHD are at a greater risk of prematurity related morbidities than premature infants without CHD. Interventions that have been successful in decreasing the risk of these morbidities are addressed.

Can Erythropoietin Reduce Hypoxemic Neurological Damages in Neonates With Congenital Heart Defects?

Congenital heart defects (CHD), the most common cause of birth defects with increasing birth prevalence, affect nearly 1% of live births worldwide. Cyanotic CHD are characterized by hypoxemia, with subsequent reduced oxygen delivery to the brain, especially critical during brain development, beginning in the fetus and continuing through the neonatal period. Therefore, neonates with CHD carry a high risk for neurological comorbidities, even more frequently when there are associated underlying genetic disorders. We review the currently available knowledge on potential prevention strategies to reduce brain damage induced by hypoxemia during fetal development and immediately after birth, and the role of erythropoietin (EPO) as a potential adjunctive treatment. Maternal hyper-oxygenation had been studied as a potential therapeutic to improve fetal oxygenation. Despite demonstrating some effectiveness, maternal hyper-oxygenation has proven to be impractical for extensive clinical application, thus prompting the investigation of specific pathways for pharmacological intervention. Among those, the role of antioxidant pathways and Hypoxia Inducible Factors (HIF) have been studied for their involvement in the protective response to hypoxic injury. One of the proteins induced by HIF, EPO, has properties of being anti-apoptotic, antioxidant, and protective for neurons, astrocytes, and oligodendrocytes. In human trials, EPO administration in neonates with hypoxic ischemic encephalopathy (HIE) significantly reduced the neurological hypoxemic damages in several reported studies. Currently, it is unknown if the mechanisms of pathophysiology of cyanotic CHD are like HIE. Neonates with cyanotic CHD are exposed to both chronic hypoxemia and episodes of acute ischemia-reperfusion injury when undergo cardiopulmonary bypass surgery requiring aortic cross-clamp and general anesthesia. Our review supports future trials to evaluate the potential efficiency of EPO in reducing the hypoxemic neurologic damages in neonates with CHD. Furthermore, it suggests the need to identify early biomarkers of hypoxia-induced neurological damage, which must be sensitive to the neuroprotective effects of EPO.

A Novel Embedded Feature Selection and Dimensionality Reduction Method for an SVM Type Classifier to Predict Periventricular Leukomalacia (PVL) in Neonates

This paper is concerned with the prediction of the occurrence of periventricular leukomalacia (PVL) in neonates after heart surgery. Our prior work shows that the Support Vector Machine (SVM) classifier can be a powerful tool in predicting clinical outcomes of such complicated and uncommon diseases, even when the number of data samples is low. In the presented work, we first illustrate and discuss the shortcomings of the traditional automatic machine learning (aML) approach. Consequently, we describe our methodology for addressing these shortcomings, while utilizing the designed interactive ML (iML) algorithm. Finally, we conclude with a discussion of the developed method and the results obtained. In sum, by adding an additional (Genetic Algorithm) optimization step in the SVM learning framework, we were able to (a) reduce the dimensionality of an SVM model from 248 to 53 features, (b) increase generalization that was confirmed by a 100% accuracy assessed on an unseen testing set, and (c) improve the overall SVM model's performance from 65% to 100% testing accuracy, utilizing the proposed iML method.

How does the convergence of prematurity and congenital heart disease impact the developing brain?

Prematurity and congenital heart disease (CHD) are individually associated with increased risk of brain injury and adverse neurodevelopmental outcomes. Delayed brain development in newborns with CHD has been documented to begin in utero and predisposes newborns with CHD to brain injury. Little is known about the combined risks when prematurity and CHD co-occur. The purpose of this review is to highlight the unique vulnerability of preterm newborns with CHD to brain dysmaturation and brain injury, and the urgent need for prospective research.

A Uniform Description of Perioperative Brain MRI Findings in Infants with Severe Congenital Heart Disease: Results of a European Collaboration

BACKGROUND AND PURPOSE

A uniform description of brain MR imaging findings in infants with severe congenital heart disease to assess risk factors, predict outcome, and compare centers is lacking. Our objective was to uniformly describe the spectrum of perioperative brain MR imaging findings in infants with congenital heart disease.

MATERIALS AND METHODS

Prospective observational studies were performed at 3 European centers between 2009 and 2019. Brain MR imaging was performed preoperatively and/or postoperatively in infants with transposition of the great arteries, single-ventricle physiology, or left ventricular outflow tract obstruction undergoing cardiac surgery within the first 6 weeks of life. Brain injury was assessed on T1, T2, DWI, SWI, and MRV. A subsample of images was assessed jointly to reach a consensus.

RESULTS

A total of 348 MR imaging scans (180 preoperatively, 168 postoperatively, 146 pre- and postoperatively) were obtained in 202 infants. Preoperative, new postoperative, and cumulative postoperative white matter injury was identified in 25%, 30%, and 36%; arterial ischemic stroke, in 6%, 10%, and 14%; hypoxic-ischemic watershed injury in 2%, 1%, and 1%; intraparenchymal cerebral hemorrhage, in 0%, 4%, and 5%; cerebellar hemorrhage, in 6%, 2%, and 6%; intraventricular hemorrhage, in 14%, 6%, and 13%; subdural hemorrhage, in 29%, 17%, and 29%; and cerebral sinovenous thrombosis, in 0%, 10%, and 10%, respectively.

CONCLUSIONS

A broad spectrum of perioperative brain MR imaging findings was found in infants with severe congenital heart disease. We propose an MR imaging protocol including T1-, T2-, diffusion-, and susceptibility-weighted imaging, and MRV to identify ischemic, hemorrhagic, and thrombotic lesions observed in this patient group.

Contrast-enhanced ultrasound of the pediatric brain

Brain contrast-enhanced ultrasound (CEUS) is an emerging application that can complement gray-scale US and yield additional insights into cerebral flow dynamics. CEUS uses intravenous injection of ultrasound contrast agents (UCAs) to highlight tissue perfusion and thus more clearly delineate cerebral pathologies including stroke, hypoxic-ischemic injury and focal lesions such as tumors and vascular malformations. It can be applied not only in infants with open fontanelles but also in older children and adults via a transtemporal window or surgically created acoustic window. Advancements in CEUS technology and post-processing methods for quantitative analysis of UCA kinetics further elucidate cerebral microcirculation. In this review article we discuss the CEUS examination protocol for brain imaging in children, current clinical applications and future directions for research and clinical uses of brain CEUS.

Perspective on Cerebral Autoregulation Monitoring in Neonatal Cardiac Surgery Requiring Cardiopulmonary Bypass

The autoregulation of cerebral blood flow protects against brain injury from transient fluctuations in arterial blood pressure. Impaired autoregulation may contribute to hypoperfusion injury in neonates and infants. Monitoring cerebral autoregulation in neonatal cardiac surgery as a guide for arterial blood pressure management may reduce neurodevelopmental morbidity. Cerebral autoregulation monitoring has been validated in animal models and in an adult trial autoregulation monitoring during bypass improved postoperative delirium scores. The nuances of pediatric cardiac disease and congenital heart surgery make simply applying adult trial findings to this unique population inappropriate. Therefore, dedicated pediatric clinical trials of cerebral autoregulation monitoring are indicated.

Motor Developmental Delay After Cardiac Surgery in Children With a Critical Congenital Heart Defect: A Systematic Literature Review and Meta-analysis

PURPOSE

To systematically review evidence regarding the severity and prevalence of motor development in children with a critical congenital heart defect (CCHD) without underlying genetic anomalies.

SUMMARY OF KEY POINTS

Twelve percent of all included studies reported abnormal mean motor developmental scores, and 38% reported below average motor scores. Children with single-ventricle physiology, especially those with hypoplastic left heart syndrome, had the highest severity and prevalence of motor delay, particularly at 0 to 12 months. Most included studies did not differentiate between gross and fine motor development, yet gross motor development was more affected.

RECOMMENDATIONS FOR CLINICAL PRACTICE

We recommend clinicians differentiate between the type of heart defect, fine and gross motor development, and the presence of genetic anomalies. Furthermore, increased knowledge about severity and prevalence will enable clinicians to tailor their interventions to prevent motor development delays in CCHD.

Parental experience of the neuromotor development of children with congenital heart disease: an exploratory qualitative study

BACKGROUND

Children with severe congenital heart disease (CHD) are a group of children at risk for neurodevelopmental impairments. Motor development is the first domain to show a delay during the first year of life and may significantly contribute to parental concerns, stress, and difficulties in early child-parent attachment. Thus, the aim of the study was to better understand the wishes and concerns of parents of children with CHD and explore their experience of their children's neuromotor development in the first year of life.

METHODS

In this qualitative study, fourteen families were recruited. Their children were aged 1-3 years and had undergone open heart surgery within the first 6 months of life. Semi-structured interviews were audio-recorded and transcribed. The data was explored within an expert group, and a qualitative content analysis was conducted using VERBI MAXQDA software 2020. The study was conducted in accordance with the COREQ checklist.

RESULTS

Parents of children with CHD reported several burdens and needs. Parental burdens concerned the child's motor development, their own physical and psychological strain, and difficulties in communication with healthcare professionals. The needs, parents reported included supporting their child's motor development, a medical coordinator, and better communication between healthcare professionals and parents. During the first phase of their children's illness, parents underwent a dynamic transitional phase and expressed the need to rely on themselves, to trust their children's abilities, and to regain self-determination in order to strengthen their self-confidence.

CONCLUSIONS

It is essential to involve parents of children with CHD at an early stage of decision-making. Parents are experts in their children and appreciate medical information provided by healthcare professionals. Interprofessional teamwork, partnering with parents, and continuous support are crucial to providing the best possible care for children and their families. Family-centred early motor intervention for CHD children might counteract the effect of parental overprotection and improve children's motor development and thus strengthen child-parent interaction. In future work, we aim to evaluate a family-centred early motor intervention for children with CHD developed on the basis of this qualitative study.

TRIAL REGISTRATION

Not applicable.

Long-Term Neurodevelopmental Outcomes of Children with Congenital Heart Defects

OBJECTIVE

To assess whether children with symptomatic congenital heart defects (CHDs) at birth (cyanosis and/or heart failure) are at greater risk of adverse neurodevelopmental outcomes at 8 years of age.

STUDY DESIGN

From a prospective population-based cohort study of newborns with CHDs (EPICARD), we included 473 children with available neurodevelopmental assessments at 8 years of age. We grouped the CHD based on symptoms at birth and need for early neonatal intervention. Ventricular septal defects that closed spontaneously within the first year of life were considered the control group. Neurodevelopmental outcomes were assessed using the Kauffman Assessment Battery Test for Children, Second Edition, for IQ (mean 100 ± 15), and the Developmental NEuroPSYchological Assessment Battery, Second Edition, for detailed assessment of specific neurocognitive domains (mean 10 ± 3). Multivariable regression analysis was used to compare the outcomes across the CHD groups after considering potentially confounding variables.

RESULTS

Compared with the control group, children with cyanotic CHD without heart failure had lower scores for IQ, -7.2 (95% CI -13.4 to -1.2). Children with noncyanotic CHD with heart failure had lower scores in the specific domains of language -1.5 (95% CI -2.2 to -0.7), and memory and learning -1.3 (95% CI -2.4; -0.3). Those with both cyanotic CHD and heart failure had lower scores for IQ, -7.6 (95% CI -13.5 to -1.8), as well as the specific domains of language and memory and learning, -2.0 (95% CI -2.9 to -1.0) and -1.1 (95% CI -2.3 to -0.1), respectively.

CONCLUSIONS

Children with symptomatic CHD at birth are at greater risk of adverse neurodevelopmental outcomes at 8 years of age, with the greatest risk for those who were born with both cyanosis and heart failure.

An introduction to and review of cardiac neurodevelopment: the risks and recommended approaches

PURPOSE OF REVIEW

To introduce the reader to the current understanding of the neurocognitive profile of congenital heart disease (CHD) survivors, the risk factors that may influence outcomes, and to the recommendations for cardiac neurodevelopmental care.

RECENT FINDINGS

A growing body of literature has shown that survivors of CHD are at increased risk for neurodevelopmental impairments. Multiple elements influence each patient's risk, which likely begins in utero and extends to perioperative management, surgical considerations, and long-term clinical care. Additionally, sociodemographic factors may compound these risks. Serial developmental follow-up is recommended for children with critical CHD.

SUMMARY

Though there are some clinical factors that increase risk, based on the high rate of developmental impairments for children with CHD, serial evaluations are recommended. Multidisciplinary and multicenter collaboration is ongoing and will facilitate moving this field forward to improve neurodevelopmental outcomes for children with CHD.