Impact of congenital heart disease on brain development in newborn infants

Postnatal Brain Trajectories and Maternal Intelligence Predict Childhood Outcomes in Complex CHD

Objective: To determine whether early structural brain trajectories predict early childhood neurodevelopmental deficits in complex CHD patients and to assess relative cumulative risk profiles of clinical, genetic, and demographic risk factors across early development. Study Design: Term neonates with complex CHDs were recruited at Texas Children's Hospital from 2005-2011. Ninety-five participants underwent three structural MRI scans and three neurodevelopmental assessments. Brain region volumes and white matter tract fractional anisotropy and radial diffusivity were used to calculate trajectories: perioperative, postsurgical, and overall. Gross cognitive, language, and visuo-motor outcomes were assessed with the Bayley Scales of Infant and Toddler Development and with the Wechsler Preschool and Primary Scale of Intelligence and Beery-Buktenica Developmental Test of Visual-Motor Integration. Multi-variable models incorporated risk factors. Results: Reduced overall period volumetric trajectories predicted poor language outcomes: brainstem ((β, 95% CI) 0.0977, 0.0382-0.1571; p = 0.0022) and white matter (0.0023, 0.0001-0.0046; p = 0.0397) at 5 years; brainstem (0.0711, 0.0157-0.1265; p = 0.0134) and deep grey matter (0.0085, 0.0011-0.0160; p = 0.0258) at 3 years. Maternal IQ was the strongest contributor to language variance, increasing from 37% at 1 year, 62% at 3 years, and 81% at 5 years. Genetic abnormality's contribution to variance decreased from 41% at 1 year to 25% at 3 years and was insignificant at 5 years. Conclusion: Reduced postnatal subcortical-cerebral white matter trajectories predicted poor early childhood neurodevelopmental outcomes, despite high contribution of maternal IQ. Maternal IQ was cumulative over time, exceeding the influence of known cardiac and genetic factors in complex CHD, underscoring the importance of heritable and parent-based environmental factors.

Outcome of humanitarian patients with late complete repair of tetralogy of Fallot: A 13-year long single-center experience

Background

Surgical repair of tetralogy of Fallot is usually performed between 3 and 6 months of age with pulmonary valve-sparing repair promoted for the best long-term result. Through a humanitarian program from developing countries, late complete surgical repair of tetralogy of Fallot has been performed at our institution for many years.

Methods

Retrospective analysis of pre- and perioperative data, as well as 30-days outcome of patients older than one year with a confirmed diagnosis of tetralogy of Fallot who had a complete surgical repair between 2005 and 2018 at our institution.

Results

One hundred sixty-five patients were included with a median age of 4.5 years [3.0-6.3], median weight of 13.5 kg [10.9 to 16.5], median transcutaneous oximetry of 78% [70 to 85] and median pulmonary valve annulus Z-score of -1.8 [-3.4 to -0.8]. There was no early surgical mortality. By multivariate analysis, only severe right ventricular hypertrophy, severe right ventricle outflow tract obstruction, and hypoplasia of the main pulmonary artery were independent predictors of failure to preserve the pulmonary annulus at surgical repair.

Conclusions

Late complete surgical repair of tetralogy of Fallot has low mortality and morbidity even when pulmonary valve-sparing repair cannot be successfully performed. The preservation of the pulmonary valve function is significantly associated with shorter ventilation time, ICU and hospital lengths of stay. In the analyzed group of patients, a pulmonary valve-sparing repair cannot be predicted exclusively based on the dimension of the pulmonary valve annulus.

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.

The Feasibility of Kangaroo Care and the Effect on Maternal Attachment for Neonates in a Pediatric Cardiac Intensive Care Unit

BACKGROUND

As survival rates in neonates with congenital heart disease have improved, research has shown they are at an increased risk for brain injury and neurodevelopmental delay. One intervention shown to have a positive impact on the development in premature and full-term newborns, as well as a positive impact on mother-infant relationship, is kangaroo care (KC). There is limited evidence to support the use of KC in infants with congenital heart disease, some of who may also be premature.

PURPOSE

The purpose of this study was to examine the safety and feasibility of introducing KC for neonates with congenital heart disease in the pediatric cardiac intensive care unit.

METHODS

A descriptive observational feasibility study was employed to evaluate the safety and efficacy of KC for this population.

RESULTS

There were 25 neonates included with 60 sessions of KC. There were no adverse events including line and tube dislodgments and physiological instability related to the use of KC.

IMPLICATIONS FOR PRACTICE

This study found KC to be safe and feasible for neonates with KC.

IMPLICATIONS FOR RESEARCH

This is the first study examining the feasibility and safety of KC in this vulnerable population of neonates. Further research should be conducted using a quasi-experimental design to investigate neurodevelopmental outcomes with a larger sample of patients.

Cerebral oxygen saturation and cerebrovascular instability in newborn infants with congenital heart disease compared to healthy controls

Objective

Infants with Congenital Heart Disease (CHD) are at risk for developmental delays, though the mechanisms of brain injury that impair development are unknown. Potential causes could include cerebral hypoxia and cerebrovascular instability. We hypothesized that we would detect significantly reduced cerebral oxygen saturation and greater cerebrovascular instability in CHD infants compared to the healthy controls.

Methods

We performed a secondary analysis on a sample of 43 term infants (28 CHD, 15 healthy controls) that assessed prospectively in temporal cross-section before or at 12 days of age. CHD infants were assessed prior to open-heart surgery. Cerebral oxygen saturation levels were estimated using Near-Infrared Spectroscopy, and cerebrovascular stability was assessed with the response of cerebral oxygen saturation after a postural change (supine to sitting).

Results

Cerebral oxygen saturation was 9 points lower in CHD than control infants in both postures (β = -9.3; 95%CI = -17.68, -1.00; p = 0.028), even after controlling for differences in peripheral oxygen saturation. Cerebrovascular stability was significantly impaired in CHD compared to healthy infants (β = -2.4; 95%CI = -4.12, -.61; p = 0.008), and in CHD infants with single ventricle compared with biventricular defects (β = -1.5; 95%CI = -2.95, -0.05; p = 0.04).

Conclusion

CHD infants had cerebral hypoxia and decreased cerebral oxygen saturation values following a postural change, suggesting cerebrovascular instability. Future longitudinal studies should assess the associations of cerebral hypoxia and cerebrovascular instability with long-term neurodevelopmental outcomes in CHD infants.

Cerebral Autoregulation in Neonates With and Without Congenital Heart Disease

BACKGROUND

Congenital heart disease (CHD) is a leading birth defect in the United States, affecting about 40 000 neonates each year. Despite efforts to prevent developmental delays, many children with CHD have neurological deficits that last into adulthood, influencing employability, self-care, and quality of life.

OBJECTIVE

To determine if neonates with CHD have impaired cerebral autoregulation and poorer neurodevelopmental outcomes compared with healthy controls.

METHODS

A total of 44 full-term neonates, 28 with CHD and 16 without, were enrolled in the study. Inclusion criteria included confirmed diagnosis of CHD, stable hemodynamic status, and being no more than 12 days old. Exclusion criteria included intraventricular hemorrhage and intubation. Cerebral autoregulation was determined by measuring regional cerebral oxygenation during a postural change. The Einstein Neonatal Neurobehavioral Assessment Scale was used to measure overall neurodevelopmental outcomes (motor, visual, and auditory functions).

RESULTS

Of the 28 neonates with CHD, 8 had single-ventricle physiology. A χ² analysis indicated no significant difference in impaired cerebral autoregulation between neonates with CHD and controls (P = .38). Neonates with CHD had lower regional cerebral oxygenation than did neonates without CHD (P < .001). Regression analyses with adjustments for cerebral autoregulation indicated that neonates with CHD had poorer total neurodevelopmental outcomes scores (β = 9.3; P = .02) and motor scores (β = 7.6; P = .04).

CONCLUSION

Preoperative neonates with CHD have poorer developmental outcomes and more hypoxemia than do controls.

Association between the use of magnesium sulfate as neuroprotector in prematurity and the neonatal hemodynamic effects

PURPOSE

Cerebral palsy is often associated with prematurity and magnesium sulfate (MgSO₄) has been used as a neuroprotector, with favorable results. However, its mechanism of action has not been fully elucidated. This study aimed to evaluate the association between MgSO₄ at the imminent premature delivery and neonatal hemodynamic effects.

MATERIALS AND METHODS

A cross-sectional study involving 94 newborns (NB) between 24 and 32 weeks at a Brazilian hospital was performed. Bivariate analysis between the use or the non-use of MgSO₄ and hemodynamic characteristics was performed, using the Chi-square test.

RESULTS

NB were evaluated between those who received MgSO₄ (27.7) and those who did not (72.3%). Normal heart rate was verified in 62.8% of NB, normal respiratory rate in 70.2%, and normal temperature in 22.3%. Oxygen saturation higher or equal than 95% was evidenced in 85.1% of NB, normal hemoglucotest in 74.5%, and hemoglobin greater or equal than 16.4 g/dL in 30.9%. Non-invasive ventilation was performed in 48.9% of NB, while 51.1% were submitted to endotracheal ventilation. There was no significance relation detected between the use of MgSO₄ and the hemodynamic characteristics.

CONCLUSIONS

MgSO₄ does not appear to influence hemodynamic factors as a cause of the neuroprotection in premature NB.

Heart transplantation in children with intellectual disability: An analysis of the UNOS database

Heart transplantation in children with intellectual disability (ID) is an issue of debate due to the shortage of available donor organs. We sought to perform the first large-scale retrospective cohort study describing the prevalence and outcomes of heart transplantation in this population. The United Network of Organ Sharing database was queried from 2008 to 2015 for pediatric patients (age <19 years) receiving first, isolated heart transplant. Recipients were divided into three subgroups: definite ID, probable ID, and no ID. The chi-square test was used to compare patients' baseline characteristics. Kaplan-Meier and Cox proportional hazard regression analyses were used to estimate the association between ID and death-censored graft failure and patient survival. Over the study period, 565 pediatric patients with definite (131) or probable (434) ID received first heart transplant, accounting for 22.4% of all first pediatric heart transplants (n=2524). Recipients with definite ID did not significantly differ from those without ID in terms of gender, ethnicity, ischemia time, severity of pretransplant condition (waitlist status, mechanical ventilation, inotrope dependence, ECMO, VAD, PVRI, infection prior to transplant), or incidents of acute rejection within the first year. ID was associated with prolonged waitlist time (P<.001). Graft and patient survival at 3 years was equivalent between children with and without ID (P=.811 and .578, respectively). We conclude that intellectual disability is prevalent in children receiving heart transplants, with 22.4% of recipients over the study period having definite or probable ID. ID does not appear to negatively affect transplantation outcomes. Future studies are needed to assess long-term outcomes of transplantation in this population.

Neurodevelopmental delay with critical congenital heart disease is mainly from prenatal injury not infant cardiac surgery: current evidence based on a meta-analysis of functional magnetic resonance imaging

OBJECTIVE

No consensus has been reached regarding whether brain injury related to congenital heart disease (CHD) is caused by infant cardiac surgery and/or prenatal injury resulting from the CHD. We performed this meta-analysis to identify the likely cause of neurodevelopmental delay in CHD patients.

METHODS

We carried out a literature search without language restriction in December 2013, retrieving records from PubMed, EMBASE, the Cochrane Library and the World Health Organization trials center, to identify studies applying functional magnetic resonance imaging (fMRI) evaluation of brain function before surgery and, in some cases, after surgery (both immediate term and short term postoperatively). The preoperative and postoperative fMRI results were extracted, and meta-analysis was performed using Revman 5.1.1 and STATA 11.0, according to the guidelines from the Cochrane review and MOOSE groups.

RESULTS

The electronic search yielded 937 citations. Full text was retrieved for 15 articles and eight articles (nine studies) were eligible for inclusion: six studies (n = 312 cases) with fMRI analysis before surgery and three (n = 36 cases) with complete perioperative fMRI analysis. The overall average diffusivity of CHD cases was significantly higher than that of controls, with a summarized standard (std) mean difference of 1.39 (95% CI, 0.70-2.08), and the fractional anisotropy was lower in CHD cases, with a summarized mean difference of -1.43 (95% CI, -1.95 to -0.91). N-acetylaspartate (NAA)/choline (Cho) for the whole brain was significantly lower in CHD cases compared with healthy ones, while lactate/Cho was significantly higher in CHD cases. Immediate term postoperatively, significant changes in NAA/creatine and NAA/Cho, relative to preoperative values, were found. However, the difference did not persist at the short-term follow-up.

CONCLUSION

This meta-analysis suggests that the delay in neurological development in newborns with CHD is due mainly to prenatal injury, and cardiac surgery might lead to mild brain injuries postoperatively, but fMRI shows recovery within a short period.

Brain volume and neurobehavior in newborns with complex congenital heart defects

OBJECTIVE

To investigate the relationship between tissue-specific alterations in brain volume and neurobehavioral status in newborns with complex congenital heart defects preoperatively.

STUDY DESIGN

Three-dimensional volumetric magnetic resonance imaging was used to calculate tissue-specific brain volumes and a standardized neurobehavioral assessment was performed to assess neurobehavioral status in 35 full-term newborns admitted to the hospital before cardiopulmonary bypass surgery. Multiple linear regression models were performed to evaluate relationships between neurobehavioral status and brain volumes.

RESULTS

Reduced subcortical gray matter (SCGM) volume and increased cerebrospinal fluid (CSF) volume were associated with poor behavioral state regulation (SCGM, P = .04; CSF, P = .007) and poor visual orienting (CSF, P = .003). In cyanotic newborns, reduced SCGM was associated with higher overall abnormal scores on the assessment (P = .001) and poor behavioral state regulation (P = .04), and increased CSF volume was associated with poor behavioral state regulation (P = .02), and poor visual orienting (P = .02). Conversely, acyanotic newborns showed associations between reduced cerebellar volume and poor behavioral state regulation (P = .03).

CONCLUSION

Abnormal neurobehavior is associated with impaired volumetric brain growth before open heart surgery in infants with complex congenital heart defects. This study highlights a need for routine preoperative screening and early intervention to improve neurodevelopmental outcomes.

Intestinal location of necrotizing enterocolitis among infants with congenital heart disease

OBJECTIVE

To determine whether differences exist in the location of necrotizing enterocolitis (NEC) in infants with congenital heart disease (CHD) versus those without CHD.

STUDY DESIGN

Retrospective cohort study utilizing 11 years of patient data. Inclusion criterion was surgical exploration for NEC. Presence or absence of CHD was determined. Surgical and/or pathology reports were reviewed to identify the location of NEC. Data were analyzed by t-tests and χ(2) analyses.

RESULT

One hundred and sixty-seven patients met the inclusion criteria. CHD infants had a higher percentage of mortality. There was no difference in the location of NEC between non-CHD and CHD patients, with the predominant location being the small intestine in both. In addition, there was no difference in the location of NEC between preterm non-CHD patients and full-term CHD patients with the small intestine again being the primary site.

CONCLUSION

Despite differences in gestational age between non-CHD and CHD patients, the location of NEC in these infants did not differ.