Morbidity and mortality in premature or low birth weight patients with congenital heart disease in three European pediatric heart centers between 2016 and 2020

Background

The treatment of preterm and low birth weight (LBW) neonates born with congenital heart disease (CHD) requiring early cardiac intervention remains challenging. We aimed to analyze morbidity and mortality in this combined high-risk patient group.

Methods

A retrospective cohort study was conducted of preterm [<37 weeks gestational age (GA)] and/or LBW neonates (<2,500 g) born with a diagnosis of CHD, which requires invasive cardiac intervention (surgery or catheter) within their first year of life. Patients born between 2016 and 2020 and treated in three European pediatric heart centers were included.

Results

A total of 308 neonates (51% male) with CHD were included. Of those, 237 (77%) were born preterm, 259 (84%) were LBW, and 188 (61%) were both. The median GA was 35.4 weeks (interquartile range 33.3-36.9) and the mean birth weight was 2,016 ± 580 g. CHD was categorized as simple (12%), moderate (64%), or severe (24%). The overall complication rate was 45% and was highest in patients with severe CHD (p = 0.002). One-year mortality (19%) was associated with severe CHD, low relative birth weight in patients with genetic diagnoses, and low GA at birth, whereas GA at birth significantly impacted survival only after 3 months of life.

Conclusions

The high morbidity and mortality in preterm and LBW neonates with CHD reflect their complexity and consequent limited treatment feasibility.

Perioperative Brain Injury in Relation to Early Neurodevelopment Among Children with Severe Congenital Heart Disease: Results from a European Collaboration

OBJECTIVE

To examine the relationship between perioperative brain injury and neurodevelopment during early childhood in patients with severe congenital heart disease (CHD).

STUDY DESIGN

One hundred and seventy children with CHD and born at term who required cardiopulmonary bypass surgery in the first 6 weeks after birth were recruited from 3 European centers and underwent preoperative and postoperative brain MRIs. Uniform description of imaging findings was performed and an overall brain injury score was created, based on the sum of the worst preoperative or postoperative brain injury subscores. Motor and cognitive outcomes were assessed with the Bayley Scales of Infant and Toddler Development Third Edition at 12 to 30 months of age. The relationship between brain injury score and clinical outcome was assessed using multiple linear regression analysis, adjusting for CHD severity, length of hospital stay (LOS), socioeconomic status (SES), and age at follow-up.

RESULTS

Neither the overall brain injury score nor any of the brain injury subscores correlated with motor or cognitive outcome. The number of preoperative white matter lesions was significantly associated with gross motor outcome after correction for multiple testing (P = .013, β = -0.50). SES was independently associated with cognitive outcome (P < .001, β = 0.26), and LOS with motor outcome (P < .001, β = -0.35).

CONCLUSION

Preoperative white matter lesions appear to be the most predictive MRI marker for adverse early childhood gross motor outcome in this large European cohort of infants with severe CHD. LOS as a marker of disease severity, and SES influence outcome and future intervention trials need to address these risk factors.

Cryogenic vacuum valve with actuation times down to 50 ms

We have conceived, built, and operated a cryogenic vacuum valve with opening and closing times as short as 50 ms that can be used in strong magnetic fields and across a broad range of duty cycles. It is used to seal a cryogenic Penning trap at liquid-helium temperature for long-term storage of highly charged ions in a vacuum better than 10-15 hPa from a room-temperature ion beamline at vacuum conditions around 10-9 hPa. It will significantly improve any experiment where a volume at the most extreme vacuum conditions must be temporarily connected to a less demanding vacuum during repeated experimental cycles. We describe the design of this valve and show measurements that characterize its main features.

Long-term neurodevelopmental outcome and serial cerebral magnetic resonance imaging assessment in Fontan patients at school age

OBJECTIVES

Children with univentricular congenital heart disease undergoing staged surgical palliation are at risk for impaired neurodevelopmental (ND) outcome. Little is known about the long-term effects on brain growth until school age.

METHODS

In a prospective two-centre study, consecutive patients undergoing stage I (Hybrid or Norwood) to stage III (Fontan procedure) were evaluated by 2 serial cerebral magnetic resonance imaging examinations, somatic growth and ND testing before Fontan procedure at 2 years of age (Bayley-III) and after Fontan at 6-8 years of age (Wechsler Intelligence Scale for Children-third edition). Magnetic resonance imaging findings were compared with 8 healthy controls. Medical and sociodemographic characteristics were documented and related to cerebral and ND findings.

RESULTS

We examined 33 children (16 female) at a mean age of 2.3 (0.35) and 6.8 (± 0.7) years. The mean Bayley-III cognitive scales were 99.1 (9.9), language scales 98.4 (11.9) and motor scales 98.5 (13.8) at the first examination. Follow-up at school age showed a mean total IQ of 86.7 (13.6). The rate of structural brain lesions increased from 39% at 2 years to 58% at school age. Bayley-III language scale (P = 0.021) and mean Wechsler Intelligence Scale for Children-third edition (P = 0.019) were lower in children with pathological MR findings. Total brain volume (P < 0.001), total grey matter volume (P = 0.002), deep grey matter volume (P = 0.001) and white matter volume (P < 0.001) were smaller in patients compared to age- and gender-matched healthy controls.

CONCLUSIONS

Smaller brain volumes and structural brain lesions in complex congenital heart defect patients at school age are associated with impaired ND outcome. For the evaluation of predictive surgical or clinical factors, larger multicentre studies are needed.

Neuromonitoring, neuroimaging, and neurodevelopmental follow-up practices in neonatal congenital heart disease: a European survey

BACKGROUND

Brain injury and neurodevelopmental impairment remain a concern in children with complex congenital heart disease (CHD). A practice guideline on neuromonitoring, neuroimaging, and neurodevelopmental follow-up in CHD patients undergoing cardiopulmonary bypass surgery is lacking. The aim of this survey was to systematically evaluate the current practice in centers across Europe.

METHODS

An online-based structured survey was sent to pediatric cardiac surgical centers across Europe between April 2019 and June 2020. Results were summarized by descriptive statistics.

RESULTS

Valid responses were received by 25 European centers, of which 23 completed the questionnaire to the last page. Near-infrared spectroscopy was the most commonly used neuromonitoring modality used in 64, 80, and 72% preoperatively, intraoperatively, and postoperatively, respectively. Neuroimaging was most commonly performed by means of cranial ultrasound in 96 and 84% preoperatively and postoperatively, respectively. Magnetic resonance imaging was obtained in 72 and 44% preoperatively and postoperatively, respectively, but was predominantly reserved for clinically symptomatic patients (preoperatively 67%, postoperatively 64%). Neurodevelopmental follow-up was implemented in 40% of centers and planned in 24%.

CONCLUSIONS

Heterogeneity in perioperative neuromonitoring and neuroimaging practice in CHD in centers across Europe is large. The need for neurodevelopmental follow-up has been recognized. A clear practice guideline is urgently needed.

IMPACT

There is large heterogeneity in neuromonitoring, neuroimaging, and neurodevelopmental follow-up practices among European centers caring for neonates with complex congenital heart disease. This study provides a systematic evaluation of the current neuromonitoring, neuroimaging, and neurodevelopmental follow-up practice in Europe. The results of this survey may serve as the basis for developing a clear practice guideline that could help to early detect and prevent neurological and neurodevelopmental sequelae in neonates with complex congenital heart disease.

Risk Factors for Perioperative Brain Lesions in Infants With Congenital Heart Disease: A European Collaboration

Background:

Infants with congenital heart disease are at risk of brain injury and impaired neurodevelopment. The aim was to investigate risk factors for perioperative brain lesions in infants with congenital heart disease.

Methods:

Infants with transposition of the great arteries, single ventricle physiology, and left ventricular outflow tract and/or aortic arch obstruction undergoing cardiac surgery <6 weeks after birth from 3 European cohorts (Utrecht, Zurich, and London) were combined. Brain lesions were scored on preoperative (transposition of the great arteries N=104; single ventricle physiology N=35; and left ventricular outflow tract and/or aortic arch obstruction N=41) and postoperative (transposition of the great arteries N=88; single ventricle physiology N=28; and left ventricular outflow tract and/or aortic arch obstruction N=30) magnetic resonance imaging for risk factor analysis of arterial ischemic stroke, cerebral sinus venous thrombosis, and white matter injury.

Results:

Preoperatively, induced vaginal delivery (odds ratio [OR], 2.23 [95% CI, 1.06–4.70]) was associated with white matter injury and balloon atrial septostomy increased the risk of white matter injury (OR, 2.51 [95% CI, 1.23–5.20]) and arterial ischemic stroke (OR, 4.49 [95% CI, 1.20–21.49]). Postoperatively, younger postnatal age at surgery (OR, 1.18 [95% CI, 1.05–1.33]) and selective cerebral perfusion, particularly at ≤20 °C (OR, 13.46 [95% CI, 3.58–67.10]), were associated with new arterial ischemic stroke. Single ventricle physiology was associated with new white matter injury (OR, 2.88 [95% CI, 1.20–6.95]) and transposition of the great arteries with new cerebral sinus venous thrombosis (OR, 13.47 [95% CI, 2.28–95.66]). Delayed sternal closure (OR, 3.47 [95% CI, 1.08–13.06]) and lower intraoperative temperatures (OR, 1.22 [95% CI, 1.07–1.36]) also increased the risk of new cerebral sinus venous thrombosis.

Conclusions:

Delivery planning and surgery timing may be modifiable risk factors that allow personalized treatment to minimize the risk of perioperative brain injury in severe congenital heart disease. Further research is needed to optimize cerebral perfusion techniques for neonatal surgery and to confirm the relationship between cerebral sinus venous thrombosis and perioperative risk factors.

Detection of early signs of right ventricular systolic impairment in unoperated Ebstein's anomaly by cardiac magnetic resonance feature tracking

BACKGROUND

Cardiovascular magnetic resonance feature-tracking analysis (CMR-FT) provides a quantitative assessment of myocardial contraction with potential for diagnostic and prognostic ability in a wide spectrum of diseases. Ebstein's anomaly (EA) is a rare congenital heart disease characterized by apical displacement of the tricuspid valve. However, it is also considered a disorder of development affecting the global right ventricular myocardium. Aim of our study is to describe the complex contractile mechanics of the functional right ventricle (RV) in patients affected by EA through CMR-FT.

METHODS

Fifty surgery-free EA patients who had undergone a complete CMR protocol at our institution between January 2017 and December 2020 were selected for the retrospective study. A historical control group of twenty-five healthy subjects was also included. CMR-FT analysis was performed at a dedicated workstation by manually tracing RV endo- end epicardial borders on steady-state-free-precession (SSFP) cine images. Strain values were calculated. Apical displacement of the tricuspid valve (TV) was measured on a 4-chamber cine image from the right atrio-ventricular junction to the functional annulus of the TV.

RESULTS

EA patients presented significantly impaired RV global radial strain (GRS) and global circumferential strain (GCS) compared to controls (P<0.0001 and P=0.0008, respectively). In a subgroup analysis, GRS was significantly compromised in patients with a severely displaced TV (>16 mm/m²) compared to milder forms (P=0.03) and to controls (P<0.0001). Among EA patients with a preserved ejection fraction, 12 (48%) vs. 6 (24%) controls had reduced both GRS and GCS.

CONCLUSIONS

The contractile pattern of the functional RV in EA is characterised by prevalent alterations in the short-axis direction as indicated by reduced GRS and GCS. Strain values might be reduced prior to routine used functional parameters like RV ejection fraction (RVEF) and can possibly serve as an early predictor of myocardial dysfunction in EA patients.

Exercise-dependent changes in ventricular-arterial coupling and aortopulmonary collateral flow in Fontan patients: a real-time CMR study

AIMS

Inefficient ventricular-arterial (V-A) coupling has been described in Fontan patients and may result in adverse haemodynamics. A varying amount of aortopulmonary collateral (APC) flow is also frequently present that increases volume load of the single ventricle. The aim of the study was to assess changes in V-A coupling and APC flow during exercise CMR.

METHODS AND RESULTS

Eighteen Fontan patients (age 24 ± 3 years) and 14 controls (age 23 ± 4 years) underwent exercise CMR using a cycle ergometer. Ventricular volumetry and flow measurements in the ascending aorta (AAO), inferior (IVC), and superior (SVC) vena cava were assessed using real-time sequences during stepwise increases in work load. Measures of systemic arterial elastance Ea, ventricular elastance Ees, and V-A coupling (Ea/Ees) were assessed. APC flow was quantified as AAO - (SVC + IVC). Ea remained unchanged during all levels of exercise in both groups (P = 0.39 and P = 0.11). Ees increased in both groups (P = 0.001 and P < 0.001) with exercise but was lower in the Fontan group (P = 0.04). V-A coupling was impaired in Fontan patients at baseline (P = 0.04). Despite improvement during exercise (P = 0.002) V-A coupling remained impaired compared with controls (P = 0.001). Absolute APC flow in Fontan patients did not change during exercise even at maximum work load (P = 0.98).

CONCLUSIONS

Inefficient V-A coupling was already present at rest in Fontan patients and aggravated during exercise due to a limited increase in ventricular contractility which demonstrates the importance of a limited functional reserve of the single ventricle. APC flow remained unchanged suggesting no further increase in volume load during exercise.

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.

Bioelastic properties of the aorta in children, adolescents and young adults after cardiac transplantation: a cardiovascular magnetic resonance study

Background

Long-term complications after cardiac transplantation are common and typically include arterial hypertension and coronary allograft vasculopathy. Few studies also suggested that heart transplant recipients have an increased arterial stiffness.

Purpose

This prospective study aimed to assess the bioelastic properties of the aorta as well as LV function, morphology and structure in children and young adults after cardiac transplantation.

Methods

CMR studies from 34 patients (median age: 17.1 years, range: 8–24 years) who underwent cardiac transplantation in childhood were analysed. Aortic anatomy and distensibility were assessed at five locations of the thoracic aorta using steady-state free precession cine sequences. Pulse wave velocity (PWV) of the aortic arch and the descending thoracic aorta was measured from 2-dimensional phase contrast images. Size and function of the left atrium and the ventricles were assessed from a stack of short axis slices. Myocardial T1 times were determined using a standard MOLLI sequence.

Results

Cross-sectional areas of the ascending aorta and the aortic arch tended to be lower in patients compared to controls (ascending aorta 464.5±172.5 mm2 vs. 515.3±186.3 mm2, aortic arch 342.4±113.3 mm2 vs. 376.9±148.5 mm2) whereas cross-sectional areas of the descending aorta tended to be higher (aortic isthmus 283.7±102.1 mm2 vs. 257.9±89.5 mm2, aorta descendens diaphragmal 218.4±75.8 mm2 vs. 214.2±75.0 mm2) and showed a correlation with systolic blood pressure (r=0.33). PWV was higher in the aortic arch (4.8±2.4 m/s vs. 3.6±0.7 m/s).

Aortic distensibility was slightly higher at all measuring points in the study population compared to the control group and showed an increase with rising distance from the heart (ascending aorta 10.5±5.8 10–3 mm Hg-1, aortic isthmus 13.1±7.5 10–3 mm Hg-1, descending aorta 16.6±6.8 10–3 mm Hg-1). Biventricular volumes were slightly reduced in the patient group compared to the control group but this was not statistically significant. Only left ventricular mass messured during the systolic phase was higher in the study population compared to the control group (males 55.1 g/m2 vs. 53.0 g/m2, females 46.2 g/m2 vs. 45.2 g/m2). T1 mapping demonstrated increased T1 times in the heart-transplanted group compared to published data in healthy adults. In particular, T1 times of the lateral and inferior myocardial segments were higher.

Conclusion

Patients who underwent cardiac transplantation in childhood seem to have a reduced bioelasticity of the thoracic aorta. Increased myocardial T1 times suggesting alterations in myocardial structure.

Funding Acknowledgement

Type of funding sources: None.

Closure of outpatient cardiac rehabilitation during the first COVID-19 lockdown in Austria in spring 2020 resulted in deteriorating physical exercise capacity: a mixed-methods study

Background

Group-based cardiac rehabilitation (CR) has inevitably been disrupted by COVID-19-related public health measures, increasing the risk of deterioration in modifiable risk factors for patients with cardiovascular disease (CVD).

Purpose

To examine the impact of CR closure during the first COVID-19-related national lockdown in Austria in spring 2020 on patients' maintenance of physical activity, physical fitness levels, and cardiovascular risk profile; and to describe the patient experience of lack of group-based CR training due to COVID-19.

Methods

This mixed-methods study recruited patients from an outpatient CR centre in Austria during summer 2020. Eligibility criteria were regular attendance at weekly group-based exercise training at the centre until the COVID-19-related lockdown in March 2020; pre-lockdown completion of a maximal cycle ergometer test; no contraindications for maximal exercise testing; and no new complaints limiting exercise performance. Participants underwent post-lockdown quantitative assessment of physical fitness (maximal cycle ergometer testing, submaximal cycle ergometer training session at individual pre-lockdown settings) and cardiovascular risk status. These were compared with pre-lockdown data from medical records. Participants gave qualitative interviews about their experience of maintaining exercise during lockdown. Interviews were audio-recorded, transcribed, coded, and interpreted using framework analysis.

Results

Twenty-eight (57%) of 49 eligible patients were recruited, 1 withdrew, and 27 completed all study procedures. Two participants were excluded from analysis of physical fitness data, due to subsequent diagnosis of new complaints limiting exercise performance. Mean (SD) age was 69 (7.4) years. Six (22%) were female. Median (IQR) time since first CVD event was 8 (5.5, 9) years. In maximal ergometer testing, 14 (56%) had deteriorated, 10 (40%) were unchanged, and 1 (4%) had improved post-lockdown. At group level, power was significantly reduced (maximal ergometer testing, submaximal ergometer training), whereas CVD risk factors remained unchanged from pre- to post-lockdown (table 1). Qualitative analysis corroborated the negative impact of the closure of CR classes (table 2).

Conclusions

This patient cohort was heterogeneous with respect to physical activity levels and exercise capacity, yet overall motivated and experienced in exercise training, having regularly attended training sessions at the centre before the lockdown. Despite individually seeking out alternative exercise options during lockdown, group average exercise capacity deteriorated even in this motivated and exercise-conscious group. This highlights the importance of providing group-based opportunities for supervised high intensity training for patients who engage well in such a setting, and the detrimental impact of disruption to this type of CR service.

Funding Acknowledgement

Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Ludwig Boltzmann Gesellschaft COVID-19 Support Measure: Open Innovation in Science (OIS) Research Enrichment Fund

The neuroendocrine effects of dehydroepiandrosterone and 17β-estradiol in the in vitro preterm hyperoxia infant model

Preterm birth causes neurological deficits. Previously, we demonstrated that fetal zone steroids reduce hyperoxia-mediated cell death in vitro. In immature oligodendrocytes (OLN-93 cells), dehydroepiandrosterone + 17β-estradiol co-treatment had synergistic beneficial effects while signals were transduced through different receptors. In immature astrocytes (C6 cells), both hormones compete for the same receptor and no synergistic effects were observed. 17β-estradiol and progesterone drastically decrease while fetal zone steroids, mainly dehydroepiandrosterone, remain persistently high within preterm infants until term. Substitution of 17β-estradiol and progesterone does not improve neurological outcomes. We investigated the influence of dehydroepiandrosterone, 17β-estradiol or dehydroepiandrosterone + 17β-estradiol treatment in C6 or OLN-93 cells on steroid receptor availability and activation of intracellular signaling molecules in hyperoxic cell culture. We sought explanations of the observed synergistic effect in preliminary study. In C6 cells, the generated signaling of dehydroepiandrosterone + 17β-estradiol treatment has no synergistic effects. The combined effect on this particular pathway does not potentiate cell survival. In OLN-93 cells, we observed significant differences in the early generated signaling of 17β-estradiol + dehydroepiandrosterone treatment to either 17β-estradiol dehydroepiandrosterone alone but never to both at the same time. The latter finding needs, therefore, further investigation to explain synergistic effects. Nevertheless, we add insight into the receptor and signaling cascade alterations induced by 17β-estradiol, dehydroepiandrosterone or 17β-estradiol + dehydroepiandrosterone treatment of C6 and OLN-93 cells in hyperoxia.

Interrelations of Intraoperative Changes in Cerebral Tissue Oxygen Saturation with Brain Volumes and Neurodevelopment Outcome After the Comprehensive Stage II Procedure in Infants With Hypoplastic Left Heart Syndrome: A Retrospective Cohort Study

OBJECTIVES

The monitoring of cerebral tissue oxygen saturation by near-infrared spectroscopy (S_cerebO₂) is used widely in pediatric cardiac anesthesia. However, little information is available on the effects of changes in perioperative S_cerebO₂ on brain morphology and neurologic outcome. The primary hypothesis tested in this study was that intraoperative S_cerebO₂ during the comprehensive stage II procedure correlated with brain volumes assessed by magnetic resonance imaging and neurodevelopmental scores.

DESIGN

Retrospective observational cohort study.

SETTING

University Hospital, Pediatric Heart Centre.

PATIENTS AND MEASUREMENTS

In 19 infants, the intraoperative course of S_cerebO₂ during the comprehensive stage II procedure was examined. Minimal S_cerebO₂ and integrated S_cerebO₂ below 45% (AUC) during surgery, as well as cerebral magnetic resonance imaging (MRI) examinations and Bayley III test at the ages of two-to-three years, were analyzed.

MAIN RESULTS

A positive correlation between minimal S_cerebO₂ and intracranial volume (p = 0.0243), total brain volume (p = 0.0243), and white matter volume (p = 0.0276) was observed, as was a negative correlation between AUC and intracranial volume (p = 0.0454) and white matter volume (p = 0.0381), respectively. No association was found between S_cerebO₂ and Bayley-III Score.

CONCLUSION

The correlation between S_cerebO₂ and brain volumes measured by MRI pointed out a possible importance of neuroprotective strategies aimed at optimizing S_cerebO₂ during complex congenital heart surgery. That no correlation between S_cerebO₂ and Bayley III Score was found suggested multifactorial causes for neurologic outcome in children with congenital heart defects.

Smaller brain volumes at two years of age in patients with hypoplastic left heart syndrome - Impact of surgical approach

BACKGROUND

Brain growth in hypoplastic left heart syndrome (HLHS) is reduced before and after birth. Little is known about further brain growth until two years of age before Fontan procedure and the potential impact of type of surgery.

METHODS

In a prospective, two-center study 29 patients with HLHS and variants were treated by Norwood (n = 5) or Hybrid procedure (n = 24). At two years of age a cerebral MRI was performed and brain volumes (total gray, deep gray, white matter) and cerebrospinal fluid volume were calculated using FreeSurfer image analysis suite and compared to a healthy control group (n = 8).

RESULTS

The total brain volumes in patients with HLHS were smaller compared to controls (HLHS: 893 ± 76 ml vs. controls: 1015 ± 148 ml, p = 0.005). This difference was found in all three brain compartments after Norwood procedure, whereas patients after Hybrid procedure had total and deep gray volumes comparable to controls. When comparing Norwood to Hybrid patients, deep gray matter volume reduction was more pronounced (Norwood: 38.4 ± 4.1 ml vs. Hybrid: 44.4 ± 3.9 ml, p = 0.005) than white matter reduction (Norwood: 255 ± 19 ml vs. Hybrid: 285 ± 31 ml, p = 0.032).

CONCLUSIONS

Smaller total and regional brain volumes were found two years after Norwood or Hybrid procedure in children with HLHS. The brain volume reduction was more distinct after Norwood than after Hybrid procedure. Longitudinal studies are needed to identify impact of early staged-surgeries on brain development and may become part of the decision-making process in individual patients.

Neurodevelopmental outcome in hypoplastic left heart syndrome after hybrid procedure

BACKGROUND

Little is known about the mid-term outcome and brain development in patients following the hybrid approach for hypoplastic left heart syndrome (HLHS). This study investigates neurodevelopmental outcome, quality of life (QoL) and brain MRI findings in HLHS preschoolers treated with the hybrid approach.

METHODS

Twenty HLHS patients (60% males) have been examined after neonatal hybrid Stage I and comprehensive stage II operation at the Pediatric Heart Center Giessen, Germany, between 2012 and 2016. Patients were evaluated with the Bayley Scales of Infant and Toddler Development III (Bayley-III), neurological examination, the Preschool Children Quality of Life Questionnaire (TAPQOL) at age 26.5±3.6 months, and again at 39.7±3.9 months with the Pediatric Cardiac Quality of Life Inventory (PCQLI). Furthermore, brain volumetric measurements and conventional brain MRI findings (27.3±4.5 months) were analyzed and compared with six healthy controls (29.2±11.1 months, P=0.53). Children with verified genetic comorbidities were excluded.

RESULTS

Mean cognitive, language, and motor composite scores on the Bayley-III were not different from healthy norms (100±15), and were 101±9.3 (P=0.48), 100±13 (P=0.93), and 98±11.7 (P=0.45), respectively. Status post stroke was the most common brain MRI abnormality, and was found in 3/19 (16%) patients, most common affecting the middle cerebral artery territory. In comparison to controls, total white matter volumes were reduced (P=0.014), and cerebrospinal fluid (CSF) volumes were increased (P=0.042) in patients. Overall health-related QoL in 2 to 3 years aged children HLHS was good, but inferior scores in the motor subscale were noted compared to healthy norms (P=0.007). However, at 3 to 4 years, parents reported comparable QoL for their children in the PCQLI to children with biventricular heart lesion.

CONCLUSIONS

HLHS patients followed by hybrid approach without major complications show a favorable neurodevelopment at 2-3 years of age. Despite extensive health-related burden, the vast majority of Fontan preschoolers with HLHS showed a good health-related QoL. Nevertheless, comprehensive care and establishing routine follow-up examinations are important to recognize long-term challenges and further improve neurodevelopmental outcome of this high-risk patient population.

Interrelationship Between Hemodynamics, Brain Volumes, and Outcome in Hypoplastic Left Heart Syndrome

BACKGROUND

The long-term impact of altered hemodynamics after stage II in children with hypoplastic left heart syndrome (HLHS) and hypoplastic left heart complex (HLHC) on cerebral growth and neurodevelopmental outcome is unknown. We aimed to investigate whether elevated central venous and atrial filling pressures before the Fontan procedure may be associated with smaller brain volumes and poorer neurodevelopmental outcome after the initial hybrid procedure.

METHODS

In a two-center cohort study semiautomated segmentation of cerebral magnetic resonance imaging scans was conducted in 25 children with HLHS/HLHC (25 hybrid) before the Fontan procedure (27.6 ± 4.3 months) and in 8 healthy control subjects (29.7 ± 9.5 months). Study patients were evaluated with the Bayley Scales of Infant and Toddler Development III (Bayley-III) and a neurologic examination. Hemodynamic measures after stage II were assessed with cardiac catheterization at 2 years of age before Fontan completion. Children with known genetic comorbidities were excluded.

RESULTS

In HLHS/HLHC patients higher atrial filling pressures (6 ± 3 mm Hg; range, 2-14) were correlated with reduced brain volumes and lower language composite score, whereas higher Glenn pressures (10 ± 3 mm Hg; range, 6-16) were related to higher cerebrospinal fluid, reduced brain volumes, and lower cognitive, language, and motoric composite scores in the Bayley-III. Compared with control subjects white matter volumes were reduced and cerebrospinal fluid volumes increased in study patients.

CONCLUSIONS

These data suggest that altered cardiovascular hemodynamics after stage II influence brain growth and neurodevelopmental outcome in infants with HLHS/HLHC.

Reduction of brain volumes after neonatal cardiopulmonary bypass surgery in single-ventricle congenital heart disease before Fontan completion

BackgroundLittle is known about the relationship between brain volumes and neurodevelopmental outcome at 2 years of age in children with single-ventricle congenital heart disease (CHD). We hypothesized that reduced brain volumes may be associated with adverse neurodevelopmental outcome.MethodsVolumetric segmentation of cerebral magnetic resonance imaging (MRI) scans was carried out in 44 patients without genetic comorbidities and in 8 controls. Neurodevelopmental outcome was assessed with the Bayley-III scales.ResultsGray matter (GM), deep GM, white matter (WM), and cerebrospinal fluid (CSF) volumes were 611±59, 43±4.5, 277±30, and 16.4 ml, respectively (interquartile range (IQR) 13.1, 23.3 ml). Children undergoing neonatal cardiopulmonary bypass surgery showed smaller deep GM (P=0.005) and WM (P=0.021) volumes. Brain volumes were smaller in patients compared with controls (GM: P=0.017, deep GM: P=0.012, and WM: P=0.015), whereas CSF volumes were greater (P=0.014). Of all intracranial volumes, only CSF volume was associated with neurodevelopmental outcome, accounting for 21% (P=0.011) of variability in the cognitive composite score when combined with common risk factors in a multivariable analysis.ConclusionIncreased CSF volume represents a significant risk factor for neurodevelopmental impairment in children with single-ventricle CHD. Later assessments are warranted to determine the prognostic role of intracranial volumes for long-term outcome.

Neurodevelopmental Outcome and Health-related Quality of Life in Children With Single-ventricle Heart Disease Before Fontan Procedure

Neurodevelopmental impairment and impaired quality of life constitute a major source of morbidity among children with complex congenital heart disease, in particular for single-ventricle (SV) morphologies. Risk factors and quality of life determining clinical and neurodevelopmental outcome at 2 years of age are examined. In a 2-center cohort study, 48 patients with SV morphology (26 hypoplastic left heart syndrome and 22 other types of univentricular heart defect) have been examined before Fontan procedure between 2010 and 2015. Patients were assessed with the Bayley Scales of Infant and Toddler Development, Third Version (Bayley-III), and the Preschool Children Quality of Life (TAPQOL) questionnaire. A total of 44 patients underwent hybrid procedure (n = 25), Norwood procedure (n = 7), or shunt or banding procedure (n = 12) as first surgery before subsequent bidirectional cavopulmonary anastomosis (n = 48). Median cognitive, language, and motor composite scores on the Bayley-III were 100 (range 65-120), 97 (68-124), and 97 (55-124), respectively. The language composite score was significantly below the norm (P = 0.025). Risk factors for poorer neurodevelopmental outcome were prolonged mechanical ventilation, longer days of hospital stay, and more reinterventions (all P < 0.05). Parents reported a good quality of life for their children. Children undergoing Fontan procedure show a favorable development and good quality of life. More complicated postoperative course and reinterventions constitute risk factors for impaired neurodevelopment. Improving postoperative management and implementing routine follow-up assessments aremeasures to further improve the neurodevelopmental outcome of this high-risk patient population.

Structural cerebral abnormalities and neurodevelopmental status in single ventricle congenital heart disease before Fontan procedure

Objectives

Neonates with single ventricle congenital heart disease are at risk for structural cerebral abnormalities. Little is known about the further evolution of cerebral abnormalities until Fontan procedure.

Methods

Between August 2012 and July 2015, we conducted a prospective cross-sectional two centre study using cerebral magnetic resonance imaging (MRI) and neuro-developmental outcome assessed by the Bayley-III. Forty-seven children (31 male) were evaluated at a mean age of 25.9 ± 3.4 months with hypoplastic left heart syndrome (25) or other single ventricle (22).

Results

Cerebral MRI was abnormal in 17 patients (36.2%) including liquor space enlargements (10), small grey (9) and minimal white (5) matter injuries. Eight of 17 individuals had combined lesions. Median (range) cognitive composite score (CCS) (100, 65-120) and motor composite score (MCS) (97, 55-124) were comparable to the reference data, while language composite score (LCS) (97, 68-124) was significantly lower ( P  = 0.040). Liquor space enlargement was associated with poorer performance on all Bayley-III subscores (CCS: P  = 0.02; LCS: P  = 0.002; MCS: P  = 0.013). The number of re-operations [odds ratio (OR) 2.2, 95% confidence interval (CI) 1.1-4.3] ( P  = 0.03) and re-interventions (OR 2.1, 95% CI 1.1-3.8) ( P  = 0.03) was associated with a higher rate of overall MRI abnormalities.

Conclusions

Cerebral MRI abnormalities occur in more than one third of children with single ventricle, while the neuro-developmental status is less severely affected before Fontan procedure. Liquor space enlargement is the predominant MRI finding associated with poorer neuro-developmental status, warranting further studies to determine aetiology and further evolution until school-age.

Protective Effects of Fetal Zone Steroids Are Comparable to Estradiol in Hyperoxia-Induced Cell Death of Immature Glia

Impaired neurodevelopment in preterm infants is caused by prematurity itself; however, hypoxia/ischemia, inflammation, and hyperoxia contribute to the extent of impairment. Because preterm birth is accompanied by a dramatic decrease in 17β-estradiol (E2) and progesterone, preliminary clinical studies have been carried out to substitute these steroids in preterm infants; however, they failed to confirm significantly improved neurologic outcomes. We therefore hypothesized that the persistently high postnatal production of fetal zone steroids [mainly dehydroepiandrosterone (DHEA)] until term could interfere with E2-mediated protection. We investigated whether E2 could reduce hyperoxia-mediated apoptosis in three immature glial cell types and detected the involved receptors. Thereafter, we investigated protection by the fetal zone steroids DHEA, 16α-hydroxy-DHEA, and androstenediol. For DHEA, the involved receptors were evaluated. We examined aromatases, which convert fetal zone steroids into more estrogenic compounds. Finally, cotreatment was compared against single hormone treatment to investigate synergism. In all cell types, E2 and fetal zone steroids resulted in significant dose-dependent protection, whereas the mediating receptors differed. The neuroprotection by fetal zone steroids highly depended on the cell type-specific expression of aromatases, the receptor repertoire, and the potency of the fetal zone steroids toward these receptors. No synergism in fetal zone steroid and E2 cotreatment was detected in two of three cell types. Therefore, E2 supplementation may not be beneficial with respect to neuroprotection because fetal zone steroids circulate in persistently high concentrations until term in preterm infants. Hence, a refined experimental model for preterm infants is required to investigate potential treatments.

Hyperoxia and the Immature Brain

Despite major advances in obstetrics and neonatal intensive care, preterm infants frequently suffer from neurological impairments in later life. Preterm and also full-term neonates are generally susceptible to injury caused by reactive oxygen species due to the immaturity of endogenous radical scavenging systems. It is well known that high oxygen levels experienced during the critical phase of maturation can profoundly influence developmental processes. Supraphysiological oxygen concentrations used for resuscitation or in the care of critically ill infants are known to have deleterious effects on the developing lung and retina, contributing to the pathophysiology of neonatal diseases like bronchopulmonary dysplasia and retinopathy of prematurity. Moreover, experimental work from the last decade suggests that hyperoxia also leads to neuronal and glial cell death, contributing to the injury of white and grey matter observed in preterm infants. During the critical phase of brain maturation, hyperoxia can alter developmental processes, resulting in the disruption of neural plasticity and myelination. However, oxygen therapy can often not be avoided in neonatal intensive care. Therefore, in situations requiring oxygen supplementation, in addition to the development of appropriate monitoring systems, protective and/or regenerative strategies are highly warranted. Here, we summarise the clinical and experimental evidence as well as potential therapeutic strategies, providing an overview of the pathophysiology of oxygen exposure on the developing central nervous system and its impact on neonatal brain injury.

Fifteen-year single center experience with the "Giessen Hybrid" approach for hypoplastic left heart and variants: current strategies and outcomes

Presented is a retrospective outcome study of a 15-year single institutional experience with a contemporary cohort of patients with hypoplastic left heart syndrome and complex that underwent a "Giessen Hybrid" stage I as initial palliation. Hybrid approach consisting of surgical bilateral pulmonary artery banding and percutaneous duct stenting with or without atrial septum manipulation was developed from a rescue approach to a first-line procedure. Comprehensive Aristotle score defined pre-operative condition. Fifteen-year follow-up mortality is reported as occurring within the staged univentricular palliation or before and after biventricular repair. Hybrid stage I was performed in 154 patients; 107 should be treated by single ventricle palliation, 33 by biventricular repair (BVR), 7 received heart transplantation, and 7 were treated by comfort care, respectively. Overall 34 children died. The Aristotle score (mean value 18.2 ± 3) classified for univentricular circulations in newborns did not have statistical impact on the outcome. Two patients died during stage I (1.2%), and the interstage I mortality was 6.7%, and stage II mortality 9%, respectively. Stage III was up to now performed in 57 patients without mortality. At 1 year, the overall unadjusted survival of HLHS and variants was 84% and following BVR 89%, respectively. The Fifteen-year survival rate for HLHS and variants was 77%, with no significant impact of birth weight of less than 2.5 kg. In conclusion, Hybrid stage I fulfilled the criteria of life-saving approach. In our institution, Hybrid procedure replaced Norwood-staged palliation with a considerable mid- and long-term survival rate. Considering interstage mortality close surveillance is mandatory.

Characterisation of recombinant immunoreactive antigens of the scab mite Sarcoptes scabiei

Sarcoptic mange (or scabies) is an important skin disease which can affect a variety of species including humans, cattle, goats, sheep, horses, pigs, rabbits, and dogs. Approximately 300 million people are affected worldwide and in lifestock animals the infestation may lead to substantial economic losses caused by depression in growth and feed conversion rates. Diagnosis of Sarcoptes infestation is difficult and only a few serological tests have been developed using whole mite antigen for diagnosis of mange in animals. Here we describe the isolation and characterisation of cDNAs of several immunoreactive clones and their recombinant expression in Escherichia coli. Three of the proteins contain repetitive sequences which suggests that they might be involved in immune evasion. The application of these antigens in serodiagnosis and the suitability for diagnosis is discussed.

The nuclear dot protein sp100, characterization of domains necessary for dimerization, subcellular localization, and modification by small ubiquitin-like modifiers

The Sp100 and promyelocytic leukemia proteins (PML) are constituents of nuclear domains, known as nuclear dots (NDs) or PML bodies, and are both covalently modified by the small ubiquitin-related protein SUMO-1. NDs play a role in autoimmunity, virus infections, and in the etiology of acute promyelocytic leukemia. To date, little is known about the function of the Sp100 protein. Here we analyzed Sp100 domains that determine its subcellular localization, dimerization, and SUMOylation. A functional nuclear localization signal and an ND-targeting region that coincides with an Sp100 homodimerization domain were mapped. Sequences similar to the Sp100 homodimerization/ND-targeting region occur in several other proteins and constitute a novel protein motif, termed HSR domain. The lysine residue of the Sp100 protein, to which SUMO-1 is covalently linked, was mapped within and may therefore modulate the previously described HP1 protein-binding site. A consensus sequence for SUMOylation of proteins in general is suggested. SUMOylation strictly depended on a functional nuclear localization signal but was not necessary for nuclear import or ND targeting. A three-dimensional structure of Sp100, which supports the mapping data and provides additional information on Sp100 structure/function relationships, was generated by computer modeling. Taken together, our studies indicate the existence of well defined Sp100 domains with functions in ND targeting, nuclear import, nuclear SUMOylation, and protein-protein interaction.

Detailed characterization of the binding site of the lipoprotein lipase-specific monoclonal antibody 5D2

Monoclonal antibody (MAb) 5D2 recognizes lipoprotein lipases (LPL) from different species but not related lipases. This MAb is a unique reagent, used world-wide, because it differentiates between monomeric inactive and dimeric active LPL, inhibits human LPL enzyme activity, and binds to C-terminal LPL sequences involved in interactions with lipoproteins, lipoprotein receptors, and heparin. In this study we have analyzed the fine specificity of the MAb epitope recognition in order to better understand its functional properties and species-specific LPL immune reactivity. In peptide scan assays, MAb 5D2 reacted with all, except two, 13 amino acid-long peptides located between positions 380 and 410. Peptides from the amino terminal end of this region reacted more strongly than those from the carboxyl terminal end. Furthermore, only a peptide from the amino terminal end competed effectively with the binding of MAb 5D2 to native LPL bound to microtiter plates or nitrocellulose. A systematic peptide mutagenesis study indicated that 8 amino acids of the reactive region, mainly located in the amino terminal end, are critical for binding and probably directly interact with MAb 5D2. The experimentally determined antigenicities of species-specific LPL peptides and of the corresponding denatured full-length LPL proteins on immunoblots were consistent with these findings. According to a proposed 3D-model for LPL, only the amino terminal end of the antigenic region is easily surface-accessible. These data combined with 3D-modelling of monoclonal antibody (MAb)-lipoprotein lipase (LPL) protein interaction provide new insight into the known biological effects of MAb 5D2 on LPL and the antigenic determinants that are recognized.

A highly amplified mouse gene is homologous to the human interferon-responsive Sp100 gene encoding an autoantigen associated with nuclear dots

In human cells, three proteins are currently known to colocalize in di screte nuclear domains (designated nuclear dots): Sp100, a transcription-activating protein autoantigenic primarily in patients with primary biliary cirrhosis; PML, a tumor suppressor protein involved in development of acute promyelocytic leukemia; and NDP52, a protein of unknown function. Here we report sequence similarities between the Sp100 protein and a putative protein encoded by a highly amplified mouse gene which is visible as an inherited homogeneously staining region (HSR) on chromosome 1 of some mouse populations. By in situ hybridization, the Sp100 gene was mapped to locus 2q37, the syntenic region of the HSR on mouse chromosome 1. Unlike the highly amplified mouse gene, Sp100 was found to be a single-copy gene and showed no restriction fragment length polymorphisms. Sequence similarities in the promoter regions and similar exon-intron organizations of the two genes were revealed. As for Sp100, steady-state levels of the mRNAs of the HSR-encoded genes could be greatly increased by interferon (IFN) treatment. As in human cells, IFN treatment led to an enlargement in both size and number of nuclear dots in mouse cells as visualized by immunofluorescence staining with autoimmune sera from patients with primary biliary cirrhosis. These data indicate that a gene located in the inherited HSR of mice, designated mSp100, is homologous to the human Sp100 gene, has a similar gene organization, and responds similarly to IFN treatment.

The occurrence of trophoblastic disease in Western Samoa

In order to study the occurrence of hydatidiform mole and choriocarcinoma in the island of Western Samoa in the South Pacific, a delivery based study was carried out. All deliveries, both livebirths and stillbirths at the main referral centre (National Hospital), all livebirths at the district hospitals/health centres and all live home deliveries 1980-87 were included. Thirty-two hydatidiform mole cases were recorded on pathological and clinical grounds. No case of choriocarcinoma was encountered. The incidence rate of hydatidiform mole was estimated to be 0.90 per 1000 deliveries, the estimated frequency rate being 1:1109 deliveries. The mean age of cases was 31 years, ranging from 19 to 48. It is suggested that the incidence of trophoblastic disease is not significant in Western Samoa in terms of geographical variations. The importance of methodology in estimating the incidence was also discussed.

Production and characterization of monoclonal antibodies against secretory proteinase of Candida albicans CBS 2730

We describe the production and characterization of three murine monoclonal antibodies (M1-M3) which are directed against different epitopes of the secretory aspartic proteinase of Candida albicans CBS 2730. All antibodies belonged to the IgM class, and they recognized denatured enzyme. Only antibody M1 was capable to react with the active proteinase. Differential reactivity was also observed with a large fragment of the proteinase of C. albicans. All antibodies recognized the corresponding proteinase of C. tropicalis 293 both in the active, and in the denatured state. Denatured porcine pepsin was also recognized by all three antibodies. However, active pepsin was recognized only by antibodies M1 and M2. The antibodies did not inhibit enzymatic activity, and they were not suited for immunofluorescence detection of proteinase on fungal cells. However, employing Western blot analysis, proteinase antigen was detected by antibody M 1 in the serum of a patient suffering from candidal pneumonia. The circulating proteinase antigen was found to be bound to patient's IgM. Implications for the use of monoclonal antibodies in the serodiagnosis of candidosis, and first experiences with other monoclonal anti-proteinase antibodies are discussed.

Penicillin-insensitive pneumococci. Case report and review

Infections due to pneumococci with decreased susceptibility (or resistance) to penicillin have been infrequently recognized. Our experience and that of others suggest that (1) penicillin susceptibility testing of significant pneumococcal isolates should become routine; (2) penicillin may not be adequate therapy for CNS infections due to pneumococci whose penicillin minimal inhibitory concentration is greater than 0.1 microgram/ml; and (3) long-term penicillin "prophylaxis" may be inappropriate in the splenectomized patient in areas where these organisms are prevalent.