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Objectives Extracorporeal cardiopulmonary resuscitation in children with refractory cardiac arrest has been shown to improve survival, however, risk factors associated with mortality and neurologic impairments are not well defined. We analyzed our recent institutional experience with pediatric extracorporeal cardiopulmonary resuscitation to identify variables associated with survival and neurocognitive outcome. Design Retrospective observational study. Setting Pediatric cardiology and congenital heart surgery departments of a tertiary referral heart center. Patients Seventy-two consecutive children (median age, 0.3 yr [0.0-1.9 yr]) who underwent extracorporeal cardiopulmonary resuscitation at our institution during the study period from 2005 to 2016. Interventions Not applicable. Measurements and main results Median duration of resuscitation was 60 minutes (42-80 min) and median extracorporeal support duration was 5.4 days (2.2-7.9 d). Forty-three (59.7%) extracorporeal cardiopulmonary resuscitation events occurred during off-hours, however, neither duration of resuscitation (65 min [49-89 min] vs 51 min [35-80 min]; p = 0.16) nor survival (34.9% vs 37.9%; p = 0.81) differed significantly compared to working hours. Congenital heart disease was present in 84.7% of the patients. Survival to hospital discharge was 36.1%; younger age, higher lactate levels after resuscitation, acute kidney injury, renal replacement therapy, hepatic injury, and complexity of prior cardiothoracic surgical procedures were significantly associated with mortality. At mid-term follow-up (median, 4.1 yr [3.7-6.1 yr]), 22 patients (84.6% of discharge survivors) were still alive with 77.3% having a favorable neurologic outcome. High lactate levels, arrest location other than ICU, and requirement for renal replacement therapy were associated with unfavorable neurologic outcome. Interestingly, longer duration of resuscitation did not negatively impact survival or neurologic outcome. Conclusions Extracorporeal cardiopulmonary resuscitation is a valuable tool for the treatment of children with refractory cardiac arrest and a favorable neurologic outcome can be achieved in the majority of survivors even after prolonged resuscitation. Mortality after extracorporeal cardiopulmonary resuscitation in postcardiac surgery children is associated with procedural complexity.

Unfavorable neurological outcome in children after cardiopulmonary resuscitation in infancy is frequent. However, few studies have investigated the development of these patients using comprehensive developmental tests and the feasibility of the Bayley Scales of Infant Development, 3rd Edition (BSID-III) has not been reported for this population. In this cross-sectional pilot study, we assessed the cognitive, language, and motor development in infants after cardiopulmonary resuscitation of ≥ 5 min with the BSID-III at the age of 12 or 24 months, depending on recruitment age. For analysis, 11 patients with in-hospital (n = 8) and out-of-hospital (n = 3) cardiac arrest were included. BSID-III results could not be quantified in three patients because of visual/hearing and/or motor impairment. In patients with quantifiable scores, 50.0% scored average in composite BSID-III scores, while the other 50.0% showed developmental delays, scoring distinctly below average. We conclude that the BSID-III is feasible for developmental assessment in the majority of the study population, but the use of instruments suitable for hearing/visually impaired and/or severely disabled infants is crucial to avoid biased results. Accurate characterization of developmental deficits is important to facilitate early identification and therapy of deficits.

OBJECTIVES We analysed our 29-year experience of surgical repair of atrioventricular septal defect (AVSD) to define risk factors for mortality and reoperation. METHODS Between 1988 and 2017, 508 patients received AVSD repair in our institution; 359 patients underwent surgery for complete AVSD, 76 for intermediate AVSD and 73 for partial AVSD. The median age of the patients was 6.1 months (interquartile range 10.3 months), and the median weight was 5.6 kg (interquartile range 3.2 kg). The standard AVSD repair was performed using 2-patch technique (n = 347) and complete cleft closure (n = 496). The results were divided into 2 surgical eras (early era 1986-2004 and late era 2004-2017). Risk factors were analysed to determine the impact of patient age, weight, the presence of trisomy 21 and complex AVSD on mortality and reoperation rate. RESULTS In-hospital mortality decreased from 10.2% (n = 26) in early surgical era to 1.6% (n = 4) in late surgical era (P

BACKGROUND The majority of children supported with ventricular assist devices (VADs) are bridged to heart transplantation. Although bridge to recovery has been reported, low recovery patient numbers has precluded systematic analysis. The aim of this study was to delineate recovery rates and predictors of recovery and to report on long-term follow-up after VAD explantation in children. METHODS Children bridged to recovery at our institution from January 1990 to May 2016 were compared with a non-recovery cohort. Clinical and echocardiographic data before and at pump stoppages and after VAD explantation were analyzed. Kaplan‒Meier estimates of event-free survival, defined as freedom from death or transplantation after VAD removal, were determined. RESULTS One hundred forty-nine children (median age 5.8 years) were identified. Of these, 65.2% had cardiomyopathy, 9.4% had myocarditis, and 24.8% had congenital heart disease. The overall recovery rate was 14.2%, and was 7.1% in patients with dilated cardiomyopathy. Predictors of recovery were age

Objective. Cold-inducible RNA-binding protein (CIRBP) has been shown to be involved not only in cooling-induced cellular protection but also as a mediator of sterile inflammation, a critical mechanism of the innate immune response in ischemia/reperfusion (I/R) injury. The role of microglia and its activation in cerebral I/R injury warrants further investigation as both detrimental and regenerative properties have been described. Therefore, we investigated the effects of cooling, specifically viability, activation, and release of damage associated molecular patterns (DAMPs) on oxygen glucose deprivation/reperfusion- (OGD/R-) induced injury in murine BV-2 microglial cells. Methods. Murine BV-2 microglial cells were exposed to 2 to 6 h OGD (0.2% O2 in glucose- and serum-free medium) followed by up to 19 h of reperfusion, simulated by restoration of oxygen (21% O2) and nutrients. Cells were maintained at either normothermia (37°C) or cooled to 33.5°C, 1 h after experimental start. Cultured supernatants were harvested after exposure to OGD for analysis of DAMP secretions, including high-mobility group box 1 (HMGB1), heat shock protein 70 (HSP70), and CIRBP, and cytotoxicity was assessed by lactate dehydrogenase releases after exposure to OGD and reperfusion. Intracellular cold-shock proteins CIRBP and RNA-binding motif 3 (RBM3) as well as caspases 9, 8, and 3 were also analyzed via Western blot analysis. Furthermore, inducible nitric oxide synthase (iNOS), ionized calcium-binding adaptor molecule 1 (Iba1), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), interleukin-1β (IL-1β), interleukin-1α (IL-1α), monocyte chemotactic protein 1 (MCP-1), transforming growth factor β (TGFβ), CIRBP, and RBM3 gene expressions were assessed via reverse transcription polymerase chain reaction, and TNF-α, IL-6, and IL-1β releases into the cultured supernatants were assessed via enzyme-linked immunosorbent assays (ELISA). Results. Prolonged exposure to OGD resulted in increased BV-2 necrotic cell death, which was attenuated by cooling. Cooling also significantly induced cold-shock proteins CIRBP and RBM3 gene expressions, with CIRBP expression more rapidly regulated than RBM3 and translatable to significantly increased protein expression. DAMPs including HMGB-1, HSP70, and CIRBP could be detected in cultured supernatants after 6 h of OGD with CIRBP release being significantly attenuated by cooling. Exposure to OGD suppressed cytokine gene expressions of IL-1β, TNF-α, MCP-1, and TGFβ independently of temperature management, whereas cooling led to a significant increase in IL-1α gene expression after 6 h of OGD. In the reperfusion phase, TNF-α and MCP-1 gene expressions were increased, and cooling was associated with significantly lower TGFβ gene expression. Interestingly, cooled Normoxia groups had significant upregulations of microglial activation marker, Iba1, IL-1β, and TNF-α gene expressions. Conclusion. BV-2 microglial cells undergo necrotic cell death resulting in DAMP release due to OGD/R-induced injury. Cooling conveyed neuroprotection in OGD/R-injury as observable in increased cell viability as well as induced gene expressions of cold shock proteins. As cooling alone resulted in both upregulation of microglial activation, expression of proinflammatory cytokines, and cold shock protein transcript and protein expression, temperature management might have ambiguous effects in sterile inflammation. However, cooling resulted in a significant decrease of extracellular CIRBP, which has recently been characterized as a novel DAMP and a potent initiator and mediator of inflammation.

The aim of the study was to evaluate the educational achievement of patients diagnosed with univentricular heart physiology (UVHP) or transposition of the great arteries (TGA) after neonatal cardiac surgery.An exploratory online survey was performed with patients registered with the National Register for Congenital Heart Defects in Germany. For this publication, a subgroup analysis was conducted among patients diagnosed with TGA (n = 173; 36.3%) and UVHP (n = 304; 63.7%).Median age of the sample at school enrollment was 6 years (range, 5-8 years). The majority were enrolled at a standard elementary school (n = 368 of 477; 77.1%), although patients with UVHP were enrolled significantly more often at a special needs school (n = 52 of 304; 17.1%, TGA patients n = 11/ of 173; 6.4%, P.001). A total of 45.8% (n = 66 of 144) of the patients graduated with a high school diploma. A substantial number of patients had been diagnosed with behavioral or learning disorders (TGA patients n = 63 of 173 [36.4%], UVHP patients n = 148 of 304 [48.7%]) and received early supportive therapy or remedial teaching before (TGA patients n = 89 of 173 [51.4%], UVHP patients n = 209 of 304 [68.8%]) and/or during their school careers (TGA patients n = 54 of 173 [31.2%], UVHP patients n = 120 of 304 [39.5%]).A large proportion of patients who underwent neonatal cardiac surgery graduated with a high school diploma. These results are of great importance to congenital heart defect patients, affected families, and treating physicians. Nevertheless, study participants, especially patients with UVHP, face some academic challenges. We conclude that long-term follow-up examinations and regular developmental assessments may be beneficial.

Children frequently require red blood cell transfusion after cardiac surgery, which can generate an inflammatory response that is associated with increased morbidity and mortality. The aim of this study was to evaluate the inflammatory response and clinical effect of RBC transfusion in children. In a pediatric prospective controlled clinical trial 48 children were randomized to an unwashed or washed red blood cell transfusion group after cardiac surgery. Red blood cells were washed using an auto transfusion device with blood gas analyses of the packed red blood cells performed before transfusion. Vital parameters, blood analyses, and plasma concentrations of cytokines were measured before and 24 h after transfusion. Forty-five children were included with 23 receiving unwashed and 22 washed red blood cells. Washing reduced hemoglobin, potassium, and glucose while increasing sodium concentration in the packed red blood cells. Increased levels of hemoglobin, hematocrit, and erythrocyte counts were observed in both groups after transfusion. Increased levels of cytokine expression (IL-1α, IL-6, IL-8, MCP-1, and TARC) were detected in the group receiving unwashed red blood cells, while IL-8 levels were reduced in patients receiving washed red blood cells. Also, the percentage increase of cytokine concentrations (IL-6, IL-8, MCP-1, and GP-VI) before in comparison to after transfusion was lower in patients receiving washed red blood cells. No significant differences in clinical outcome parameters were observed between the two groups. Transfusion of red blood cells induces a pro-inflammatory reaction which can be diminished by washing the red blood cells before transfusion. Further clinical trials with larger patient cohorts receiving multiple transfusions are needed to better evaluate the clinical outcome.

Purpose Recently, a novel mobile driving unit (MDU) of the only approved pediatric ventricular assist device (VAD) system for both short- and long-term support of children of all sizes and ages received market approval. The MDU was specifically developed to improve mobility and autonomy of children supported with this paracorporeal (pc) VAD. This case series collects initial information with the aim to assess the first clinical experience. Methods A retrospective case series gathered anonymized patient health data of pediatric patients supported with MDU. The usability was assessed by means of a patient standardized questionnaire (numerical scale, 1= worst to 5= best). Results From February 2020 until September 2020, eight children (3 females) have been supported with a pc VAD in combination with the MDU. The median age was 1.4 years (range 0.5 - 7.5), median body surface area 0.4 m2 (0.3 - 0.9). Primary diagnosis was cardiomyopathy (CM) in 7 patients (5 dilated and 2 restrictive CM), and congenital heart disease in one child. Five patients (62.5%) received a pc VAD as left-sided and two patients as biventricular support (BVAD, 25%). One had a secondary right-sided pc VAD in combination with an implantable left-sided centrifugal VAD. The distribution of pc pump chambers by size was 10 ml pump: 2 patients (25%), 15 ml pump: 4 subjects (50%) and 30 ml pump: 2 children (25%), plus 15 ml pumps in both pc BVAD patients. The mean time of VAD support was 406 ± 241 days, with 148 ± 76 days on MDU. At the end of the observational period, 5 patients (62.5%) were still on system, 2 (25%) were transplanted and 1 died (12.5%) for causes not related to the driving unit. The survey found increased mobility (score 4.2/5), enlarged activity radius (5/5) and reduced noise nuisance (4.5/5) with MDU in comparison to the stationary unit. There were no complaints in MDU handling reported and the easiness to use was rated (4.5/5). In addition the parents reported a significant less heat generation by the MDU. The safety profile of MDU showed five adverse events: one fatal case (12.5%), one respiratory failure (12.5%), both not device-related, and two pump malfunctions (25%). One patient (12.5%) underwent pump replacement due to fibrin debris. Conclusion The case series suggests that the novel MDU is safe and effective for VAD support in the pediatric population. It is likely that MDU will increase the quality of life in this cohort.

We assessed the dynamics in the prevalence of children with congenital heart disease (CHD) and Down syndrome in Germany with regard to phenotype, severity, and gender. Data from patients with CHD and Down syndrome born between 1980 and 2014 were analyzed, who are registered with the German National Register for Congenital Heart Defects. One thousand six hundred eighteen CHD patients with Down syndrome were identified. The prevalence of children born with both Down syndrome and CHD was constant from 2005 to 2009 but increased from 2010 to 2014. Regarding CHD groups, complex and simple lesions have become more equal since 2005. The number of simple lesions with shunt has a peak prevalence in the period of 2010-2014. Atrioventricular septal defect was the most common CHD phenotype, but temporal changes were found within the group of CHD phenotypes over the observation period.Our findings suggest a growing number of CHD and Down syndrome, which may be the result of improved medical management and progress in educational, social, and financial support. This development is noteworthy as it adds new aspects to present discussions in the media and political settings. What is known: • Congenital heart disease is regarded to be the most important clinical phenomenon in children with Down syndrome, due to its significant impact on morbidity and mortality. • New developments in prenatal diagnostic and therapy management of congenital heart disease continue to influence the number of patients diagnosed with congenital heart disease and Down syndrome. What is New: • This study provides essential data giving the first overview of the dynamics in the prevalence of congenital heart disease and Down syndrome over an extended length of time up to 2015 in a large patient cohort, taking recent developments into account. • Our data suggest a growing prevalence of congenital heart disease and Down syndrome, which may be the result of improved medical management for Down syndrome patients and progress in educational, social, and financial support for their families; this development is noteworthy as it adds new aspects to the present discussion in the media and political settings.

PurposeThrough this study we aimed to assess the educational level and employment status of adults with CHD in Germany.MethodsData were acquired from an online survey carried out in 2015 by the German National Register for Congenital Heart Defects. A total of 1458 adults with CHD participated in the survey (response rate: 37.6%). For 1198 participants, detailed medical information, such as main cardiac diagnosis and information from medical reports, was available.ResultsOf the participants surveyed (n=1198), 54.5% (n=653) were female, and the mean age was 30 years. The majority of respondents (59.4%) stated that they had high education levels and that they were currently employed (51.1%). Patients with simple CHD had significantly higher levels of education (pConclusionsMore than half of the participants had high education levels and the majority were employed. The association between CHD and its severity and individuals’ educational attainment should be investigated more closely in future studies.

Objective Therapeutic hypothermia has been shown to attenuate myocardial cell death due to ischemia/reperfusion injury. However, cellular mechanisms of cooling remain to be elucidated. Especially during reperfusion, mitochondrial dysfunction contributes to cell death by releasing apoptosis inductors. The aim of the present study was to investigate the effects of moderate therapeutic hypothermia (33.5 °C) on mitochondrial mediated apoptosis in ischemia/reperfusion-injured cardiomyocytes. Methods Ischemic injury was simulated by oxygen-glucose deprivation for 6 h in glucose/serum-free medium at 0.2% O2 in mouse atrial HL-1 cardiomyocytes. Simulation of reperfusion was achieved by restoration of nutrients in complete supplemented medium and incubation at 21% O2. Early application of therapeutic hypothermia, cooling during the oxygen-glucose deprivation phase, was initiated after 3 h of oxygen-glucose deprivation and maintained for 24 h. Mitochondrial membrane integrity was assessed by cytochrome c and AIF protein releases. Furthermore, mitochondria were stained with MitoTracker Red and intra-cellular cytochrome c localization was visualized by immunofluorescence staining. Moreover, anti-apoptotic Bcl-2 and Hsp70 as well as phagophore promoting LC3-II protein expressions were analyzed by Western-blot analysis. Results Therapeutic hypothermia initiated during oxygen-glucose deprivation significantly reduced mitochondrial release of cytochrome c and AIF in cardiomyocytes during reperfusion. Secondly, anti-apoptotic Bcl-2/Bax ratio and Hsp70 protein expressions were significantly upregulated due to hypothermia, indicating an inhibition of both caspase-dependent and -independent apoptosis. Furthermore, cardiomyocytes treated with therapeutic hypothermia showed increased LC3-II protein levels associated with the mitochondria during the first 3 h of reperfusion, indicating the initiation of phagophores formation and sequestration of presumably damaged mitochondrion. Conclusion Early application of therapeutic hypothermia effectively inhibited cardiomyocyte cell death due to oxygen-glucose deprivation/reperfusion-induced injury via multiple pathways. As hypothermia preserved mitochondrial membrane integrity, which resulted in reduced cytochrome c and AIF releases, induction of both caspase-dependent and -independent apoptosis was minimized. Secondly, cooling attenuated intrinsic apoptosis via Hsp70 upregulation and increasing anti-apoptotic Bcl-2/Bax ratio. Moreover, therapeutic hypothermia promoted mitochondrial associated LC3-II during the early phase of reperfusion, possibly leading to the sequestration and degradation of damaged mitochondrion to attenuate the activation of cell death.

Objective:We developed the Long-term Early Development Research (LEADER) project to investigate the development of children with CHD and/or after cardiopulmonary resuscitation. Both populations are at risk for delays in motor, cognitive, and language development. However, few studies to date have investigated the longitudinal development in these children.Methods:To establish a clinical research unit, we planned three studies: a cross-sectional study in children after cardiopulmonary resuscitation (LEADER-REA Pilot Study), a longitudinal study in children after cardiopulmonary resuscitation, with a focus on evaluating various biomarkers as predictors for developmental outcome (LEADER-CPR study), and a longitudinal study in children with ventricular septal defect, tetralogy of Fallot, or transposition of the great arteries after cardiac surgery (LEADER-CHD study).Results:Implementation of all three LEADER studies was successful and study protocols were conducted as planned. Findings from the LEADER-REA Pilot study have been recently published and data collection for both prospective trials is ongoing. Descriptive analysis of the first 20 assessments of the LEADER-CHD study showed no severe deficits in overall cognitive, motor, and language developments in the children.Conclusions:Children with CHD and/or after cardiopulmonary resuscitation are at risk for developmental delay. Therefore, a detailed developmental assessment is necessary as a pre-requisite for individual developmental support. Our LEADER project has been shown to be feasible in a clinical setting and is the first step towards the establishment of a clinical research unit in our clinic with a focus on longitudinal research.

Background Survival rates of children with congenital heart disease (CHD) have increased significantly in the decade. There is now increased interest in the long-term outcome and quality of life of these children. Aims To assess the educational achievement of patients with CHD in Germany. Study design Cross-sectional study using an online survey. The recruitment of study participants was carried out via the database of the German National Register for Congenital Heart Defects (NRCHD). Subjects Patients born between 1992 and 2011 were enrolled in the study. For 2609 study participants (female = 1870 (71.7%); 1072 (41.1%) patients; 1537 (58.9%) parents), who participated in the survey, detailed information regarding the underlying CHD diagnosis and clinical data was available. Outcome measures Age at enrollment, secondary school form, school year repetition, school degree. Results The large majority of study participants were enrolled at a conventional elementary school (83.4%) and started school at the age of 6 years or below (73.3%). In total 45.7% of graduated study participants graduated with the qualification necessary to study at any university. In terms of analysis of the different CHD severity subgroups 57.3% of patients with a mild CHD, 47.5% with a moderate CHD and only 35.1% suffering from a severe CHD attained a high school diploma. Conclusions In our study, the majority of participating CHD patients had a standard school career. These initial results are of great importance to affected families and treating physicians as they show that, in general, a normal school career is possible for all CHD patients.

OBJECTIVES To assess our practice according to the Society of Thoracic Surgeons and the European Association for Cardio-Thoracic Surgery (STS-EACTS) Mortality Score and to the new concept of unit performance. METHODS All main procedures carried out in the years 2012-2016 were analysed. The STS-EACTS model-based mortality risk procedure was used to calculate expected mortality. Surgical performance was estimated as the Aristotle complexity score multiplied by hospital survival. Unit performance was defined as surgical performance multiplied by the number of procedures. RESULTS In total, 2435 procedures were analysed. One hundred and two deaths (95% confidence interval 71-135 deaths) were expected; 43 patients died after operation. Observed mortality divided by expected mortality was 0.42. The ratio ranged from 0.23 (year 2014) to 0.59 (year 2013) and was

Objectives The search for an optimal patch material for aortic valve reconstruction (AVR) is an ongoing challenge. In this study, we report our experience of AVR using decellularized bovine pericardial patch material in congenital heart surgery. Methods Data of 40 consecutive patients who underwent AVR using the CardioCel® patch (Admedus Regen Pty Ltd, Perth, WA, Australia) between February 2014 and August 2016 were retrospectively reviewed. The median age of the patients at operation was 9 (2-34) years, and 18 patients were younger than 7 years. Twenty-six patients initially presented with aortic valve insufficiency (AI) and 14 with stenosis. Clinical and echocardiographic data were available until August 2017 for a median postoperative follow-up (FU) of 22 (6-42) months. Results Nine of 40 (23%) patients experienced an event during FU (death: n = 1, 2.5%; reoperation: n = 8, 20%). Overall, the probability of freedom from reoperation or death was 97 ± 3%, 76 ± 9% and 57 ± 12% at 12, 24 and 36 months of FU, respectively. Reason for reoperation was stenosis in 3 (37.5%) patients, insufficiency in 4 (50%) patients and 1 (12.5%) patient was diagnosed with aortic valve endocarditis. Of the remaining 31 patients, 2 patients are scheduled for reoperation (aortic valve stenosis: n = 1 and AI: n = 1) and 9 patients exhibit worsening of aortic valve function with moderate AI. Freedom from developing combined end point [death/reoperation/moderate degree of aortic valve dysfunction (aortic valve stenosis, AI)] after AVR was 92 ± 5%, 55 ± 9% and 28 ± 9% at 12, 24 and 36 months, respectively. Conclusions AVR using decellularized bovine pericardial patch material in patients with congenital aortic valve disease show unsatisfactory results within the first 3 years of FU.

Minimizing the systemic inflammatory response caused by cardiopulmonary bypass is a major concern. It has been suggested that the perfusion temperature affects the inflammatory response. The aim of this prospective study was to compare the effects of moderate hypothermia (32°C) and normothermia (36°C) during cardiopulmonary bypass on markers of the inflammatory response and clinical outcomes (time on ventilator) after surgical closure of ventricular septal defects. During surgical closure of ventricular septal defects under cardiopulmonary bypass, 20 children (median age 4.9 months, range 2.3-38 months; median weight 7.2 kg, range 5.2-11.7 kg) were randomized to a perfusion temperature of either 32°C (Group 1, n = 10) or 36°C (Group 2, n = 10). The clinical data and blood samples were collected before cardiopulmonary bypass, directly after aortic cross-clamp release, and 4 and 24 h after weaning from cardiopulmonary bypass. Time on ventilation as primary outcome did not differ between the two groups. Other clinical outcome parameters like fluid balance or length of stay in the intensive care were also similar in the two groups. Compared with Group 2, Group 1 needed significantly higher and longer inotropic support (P

Beta-blockers contribute to treatment of heart failure. Their mechanism of action, however, is incompletely understood. Gradients in beta-blocker sensitivity of helically aligned cardiomyocytes compared with counteracting transversely intruding cardiomyocytes seem crucial. We hypothesize that selective blockade of transversely intruding cardiomyocytes by low-dose beta-blockade unloads ventricular performance. Cardiac magnetic resonance imaging (MRI) 3D tagging delivers parameters of myocardial performance. We studied 13 healthy volunteers by MRI 3D tagging during escalated intravenous administration of esmolol. The circumferential, longitudinal, and radial myocardial shortening was determined for each dose. The curves were analyzed for peak value, time-to-peak, upslope, and area-under-the-curve. At low doses, from 5 to 25 μg·kg−1·min−1, peak contraction increased while time-to-peak decreased yielding a steeper upslope. Combining the values revealed a left shift of the curves at low doses compared with baseline without esmolol. At doses of 50 to 150 μg·kg−1·min−1, a right shift with flattening occurred. In healthy volunteers we found more pronounced myocardial shortening at low compared with clinical dosage of beta-blockers. In patients with ventricular hypertrophy and higher prevalence of transversely intruding cardiomyocytes selective low-dose beta-blockade could be even more effective. MRI 3D tagging could help to determine optimal individual beta-blocker dosing avoiding undesirable side effects.

Objectives Therapeutic hypothermia (TH) is an acknowledged strategy for neuroprotection for patients suffering from hypoxic–anoxic brain injury (HAI). Albeit similar pathomechanisms of HAI for both brain and heart, moderate TH (32–34 °C) has not been established as a heart-protective measure. Therefore, we investigated the cardioprotective effects of moderate TH on oxygen–glucose deprivation/re-oxygenation (OGD/R)-induced injury in HL-1 cardiomyocytes. Methods Cardiac OGD/R injury was induced by exposing HL-1 cardiomyocytes to 0.2% oxygen in serum/glucose-free medium for 6 h. OGD injured cells were subsequently re-oxygenated with 21% oxygen in complete medium. Two hypothermic protocols were investigated: Post-OGD cooling to 33.5 °C for 24 h initiated at the start of re-oxygenation and intra-OGD cooling to 33.5 °C for 24 h initiated after 3 h of OGD and maintained throughout the re-oxygenation phase. Cell viability was determined by LDH and cTnT releases. Mitochondria dysfunction was evaluated by intracellular ATP content and cellular metabolic activity was accessed by MTT reduction. Activation of caspase 3 was analyzed by Western blot. Results OGD/R-induced injury resulted in increased cell death (higher LDH and cTnT releases), mitochondrial impairment (decreased ATP content), and decreased cellular metabolic activity (decreased MTT reduction). Only intra-OGD cooling attenuated both OGD and OGD–R-induced injuries (significantly decreased LDH and cTnT releases and increased ATP contents and MTT reduction). Furthermore, caspase 3 activation was abated by intra-OGD cooling. No protective effects were observed by post-OGD cooling. Conclusions Moderate TH initiated during OGD is a promising intervention for the protection of cardiomyocytes from OGD/R-induced injury. The attenuation of mitochondrial dysfunction and apoptosis by intra-OGD cooling are beneficial effects of hypothermia-induced cardioprotection, resulting in minimized myocardial cell death after OGD and OGD–R-induced injuries.

Objective To assess the prevalence of congenital heart disease (CHD) in Germany in relation to phenotypes, severity and gender. Design Cross-sectional registry study. Setting We analyzed data from patients with CHD born between 1996 and 2015. Patients A total of 26 630 patients, registered with the NRCHD, were born between 1996 and 2015. 10 927 patients were excluded from the current analysis due to prior registration with the NRCHD under the German PAN Prevalence Study, which showed a potential bias in the inclusion of this patient population (proportion of mild cardiac lesions was comparatively high due to improved diagnostic capability for earlier identifying minor lesions). At least 15 703 patients with demographic data and detailed medical information were included in the current study. Interventions None. Outcome Measures Prevalence of CHD in Germany differentiated into gender, severity, and phenotype. Results In total, 15 703 patients with CHD (47.1% female) were included in this study. The five most common phenotypes were found to be ventricular septal defect (19.2%), atrial septal defect (13.0%), Tetralogy of Fallot (9.3%), univentricular heart (9.4%), and coractation of the aortae (7.0%). The prevalence of CHD in regard to severity changed over the duration of the observation period. From 1996 to 2007, the number of simple CHD rose steadily (P

Lisa-Maria Rosenthal,1 Giang Tong,1 Christoph Walker,1 Sylvia J Wowro,1 Jana Krech,1 Constanze Pfitzer,1,2 Georgia Justus,1 Felix Berger,1,3 Katharina Rose Luise Schmitt1 1Department of Congenital Heart Disease/Pediatric Cardiology, German Heart Institute Berlin, 2Berlin Institute of Health (BIH), 3Department of Pediatric Cardiology, Charité – University Medical Center, Berlin, Germany Objective: Therapeutic hypothermia is an established treatment for perinatal asphyxia. Yet, many term infants continue to die or suffer from neurodevelopmental disability. Several experimental studies have demonstrated a beneficial effect of mild-to-moderate hypothermia after hypoxic injury, but the understanding of hypothermia-induced neuroprotection remains incomplete. In general, global protein synthesis is attenuated by hypothermia, but a small group of RNA-binding proteins including the RNA-binding motif 3 (RBM3) is upregulated in response to cooling. The aim of this study was to establish an in vitro model to investigate the effects of hypoxia and hypothermia on neuronal cell survival, as well as to examine the kinetics of concurrent cold-shock protein RBM3 gene expression. Methods: Experiments were performed by using human SK-N-SH neurons exposed to different oxygen concentrations (21%, 8%, or 0.2% O2) for 24 hours followed by moderate hypothermia (33.5°C) or normothermia for 24, 48, or 72 hours. Cell death was determined by quantification of lactate dehydrogenase and neuron-specific enolase releases into the cell cultured medium, and cell morphology was assessed by using immunofluorescence staining. The regulation of RBM3 gene expression was assessed by reverse transcriptase-quantitative polymerase chain reaction and Western blot analysis.Results: Exposure to hypoxia (0.2% O2) for 24 hours resulted in significantly increased cell death in SK-N-SH neurons, whereas exposure to 8% O2 had no significant impact on cell viability. Post-hypoxia treatment with moderate hypothermia for 48 or 72 hours rescued the neurons from hypoxia-induced cell death. Moreover, exposure to severe hypoxia led to observable cell swelling, which was also attenuated by moderate hypothermia. Finally, moderate hypothermia but not hypoxia led to the induction of RBM3 expression on both transcriptional and translational levels.Conclusion: Moderate hypothermia protects neurons from hypoxia-induced cell death. The expression of the cold-shock protein RBM3 is induced by moderate hypothermia and could be one possible mediator of hypothermia-induced neuroprotection. Keywords: RBM3, cold-inducible RNA-binding protein, hypothermia, neuroprotection, hypoxia

To investigate if the serum biomarkers of cerebral injury, neuron-specific enolase and S100b protein, may classify unfavourable neurological outcome after paediatric cardiac arrest.We performed a retrospective study of neuron-specific enolase and S100b measurements from 95 children treated in our paediatric cardiac intensive care unit after cardiac arrest. Neurological outcome at discharge was evaluated using the paediatric cerebral performance category scale, with unfavourable outcome defined as a change of1 compared to pre-arrest status or death.Fifty-eight patients (61.1%) survived to discharge with 48 (50.5%) having a favourable neurological outcome. We observed significantly higher levels of both biomarkers in the unfavourable outcome group at designated time points (neuron-specific enolase at 24, 48, and 72h and S100b at 12, 24, and 48h after cardiac arrest, p0.05). Receiver operating characteristic areas under the curve for neuron-specific enolase were 0.83, 0.80, and 0.73 at time points 24, 48, and 72h and 0.87, 0.81, and 0.82 for S100b at 12, 24, and 48h after cardiac arrest, respectively. Neuron-specific enolase measurement at 24h after cardiac arrest was an independent predictor of unfavourable outcome in a multivariable analysis.Neuron-specific enolase and S100b classify unfavourable neurological outcome in this large paediatric cardiac arrest cohort. Further multi-institutional prospective studies to comprehensively evaluate the diagnostic accuracy of these biomarkers under various clinical conditions and to determine reliable cut-off values in children are warranted.

Background Adults with congenital heart disease (ACHD) have an increased risk for infective endocarditis (IE). In the last decade, the recommendations for IE prophylaxis have changed substantially. The knowledge level of patients about IE and IE prophylaxis has not been studied. Methods Patients recruited via the German National Register for Congenital Heart Defects were invited to an online survey about IE. Patients were divided into two groups based on ESC guidelines: high IE risk (antibiotic prophylaxis recommended) and low IE risk (prophylaxis not recommended). Results Overall, 1458 patients participated and out of these 1211 (age 30.5±11.8years, female=54.2%) with detailed clinical information were further analyzed. 343 patients had a high IE risk, whereas 868 had a low risk. Overall, 74.5% (n=902) stated to know what IE is (low IE risk: 71.3%, high IE risk: 82.5%) Out of these who stated to know what IE is (n=902), 76.5% (n=690) chose the correct answer in a multiple choice question (low IE risk: 76.4%; high IE risk: 76.7%). Antibiotic prophylaxis was known to 66.2% (low IE risk: 59.9%; high IE risk: 82.2%). Out of these who stated to know what antibiotic prophylaxis is (n=802), 83.8% (n=672) chose the correct answer in a multiple choice question (low IE risk: 82.9%; high IE risk: 85.5%). Conclusions This study reveals important knowledge gaps regarding IE and antibiotic prophylaxis in ACHD patients. A discussion about IE and antibiotic prophylaxis should take place with every ACHD patient during regular clinical contacts to close this knowledge gap.

Deep hypothermia therapy (HT) is a standard method for neuroprotection during complex pediatric cardiac surgery involving extracorporeal circulation and deep hypothermic cardiac arrest. The procedure, however, can provoke systemic inflammatory response syndrome (SIRS), one of the most severe side effects associated with pediatric cardiac surgery. To date, the cellular inflammatory mechanisms induced by deep HT remain to be elucidated. Therefore, we investigated the effects of deep HT (17°C) and rewarming on the inflammatory response in lipopolysaccharide (LPS) stimulated BV-2 murine microglia. Additionally, we also investigated the application of Stattic, a signal transducer and activator of transcription 3 (STAT3) activation inhibitor, as an alternative to physical cooling to attenuate the LPS-induced inflammatory response. Deep HT had no cytotoxic effect but attenuated microglia migration. IκBα degradation was delayed by deep HT resulting in the attenuation of pNF-κB p65 migration into the nucleus and significant decreases in pro-inflammatory IL-6, TNF-α, and MCP-1 expressions and secretions, as well as decreased anti-inflammatory IL-10 and SOCS3 expressions. Additionally, pStat3 was significantly down regulated under deep hypothermic conditions, also corresponding with the significant reduction in IL-6 and TNF-α expressions. Similar to the effects of HT, the application of Stattic under normothermic conditions resulted in significantly reduced IL-6 and TNF-α expressions. Moreover, attenuation of the inflammatory response resulted in decreased apoptosis in a direct co-culture of microglia and neurons. HT reduces the inflammatory response in LPS-stimulated BV-2 microglial cells, alluding to a possible mechanism of therapeutic hypothermia-induced neuroprotection. In the future, attenuating the phospho-STAT3 pathway may lead to the development of a neuroprotectant with greater clinical efficacy.

The genetic basis of congenital heart disease remains unknown in most of the cases. Recently, a novel mouse model shed new light on the role of CCN1/CYR61, a matricellular regulatory factor, in cardiac morphogenesis. In a candidate gene approach, we analyzed a cohort of 143 patients with atrial septal defects (ASD) by sequencing the coding exons of CCN1. In addition to three frequent polymorphisms, we identified an extremely rare novel heterozygous missense mutation (c.139C > T; p.R47W) in one patient with severe ASD. The mutation leads to an exchange of residues with quite different properties in a highly conserved position of the N-terminal insulin-like growth factor binding protein module. Further bioinformatic analysis, exclusion of known ASD disease genes as well as the exclusion of the mutation in a very high number of ethnically matched controls (more than 1,000 individuals) and in public genetic databases, indicates that the p.R47W variant is a probable disease-associated mutation. The report about ASD in mice in heterozygous Ccn 1 +/- animals strongly supports this notion. Our study is the first to suggest a relationship between a probable CCN1 mutation and ASD. Our purpose here was to draw attention to CCN1, a gene that we believe may be important for genetic analysis in patients with congenital heart disease.

Background Corrective surgery for congenital heart defects is known to trigger a severe immune reaction. There has been extensive research on the effects of inflammation after cardiopulmonary bypass (CPB). Interestingly, monocytes are observed to be non-responsive to stimulation with lipopolysaccharide (LPS) under these conditions, indicating a state of immunodepression, which lays the ground for second hit infections after cardiosurgery with CPB. Objectives The aim of this prospective study was to analyze immunodepression after pediatric cardiopulmonary bypass and to differentiate the effects of monocytic anergy on postoperative outcome. Methods In a prospective trial, we quantified the immune responses in 20 pediatric patients (median age 4.9 months, range 2.3–38.2 months; median weight 7.2 kg, range 5.2–11.7 kg) with congenital ventricular septal defect undergoing heart surgery with CPB. Ex vivo LPS-induced protein expression of IFN-γ, IL-1β, IL-1Ra, IL-6, IL-8, IL-10, IL-12, IL-17, TNF-α, and MCP-1 was measured before (T1), immediately after (T2) and 4 h after (T3) cardiopulmonary bypass surgery using Luminex technology. Results The innate immune system responds to CPB with an almost complete depression of monocytic function. Inflammatory IL-12, TNF-α, IL-1β, IL-6, IL-8 and IFN-y are completely suppressed. IL-10, IL-1Ra and MCP-1 are still produced during suppression with IL-1Ra being overly secreted during reversion. Suppression of TNF-α expression after LPS-stimulation correlates closely with longer mechanical ventilation time (r = −0.619, p = 0.004). Conclusion Cardiosurgery with CPB causes a state of immunodepression making pediatric patients more vulnerable to second hit infections. MCP-1, IL-10, and IL-1Ra play an important role in monocyte recovery, eventually permitting new therapeutic options for controlling immunodepression and inflammation. Standardized glucocorticoid therapy should be evaluated carefully for each individual patient.

Therapeutic hypothermia has emerged as an effective neuroprotective therapy for cardiac arrest survivors. There are a number of purported mechanisms for therapeutic hypothermia, but the exact mechanism still remains to be elucidated. Although hypothermia generally down-regulates protein synthesis and metabolism in mammalian cells, a small subset of homologous (>70%) cold-shock proteins (RNA-binding motif protein 3, RBM3 and cold-inducible RNA-binding protein, CIRP) are induced under these conditions. In addition, RBM3 up-regulation in neuronal cells has recently been implicated in hypothermia-induced neuroprotection. Therefore, we compared the effects of moderate (33.5 °C) and deep (17 °C) hypothermia with normothermia (37 °C) on the regulation of RBM3 and CIRP expressions in murine organotypic hippocampal slice cultures (OHSC), hippocampal neuronal cells (HT-22), and microglia cells (BV-2). Moderate hypothermia resulted in significant up-regulation of both RBM3 and CIRP mRNA in murine OHSC, but deep hyporthermia did not. RBM3 protein regulation was also significantly up-regulated by 33.5 °C, but no significant up-regulation of CIRP protein was observed in the OHSC. Additionally, OHSC exposed to 17 °C for 24 h were positive for Propidium Iodide (PI) immunostaining, indicating the onset of cell death. Similarly, RBM3 gene expression in a HT-22 neuronal cells mono-culture and direct co-culture of HT-22 neuronal cells with BV-2 microglia cells were also up-regulated at 33.5 °C but only in the co-culture at 17 °C. No significant up-regulation of RBM3 nor CIRP gene expression were observed in a BV-2 mono-culture at either temperature. We observed that RBM3 mRNA and protein expressions in murine OHSC, as well as in mono-culture of HT-22 neuronal cells and direct co-culture of HT-22 neuronal cells with BV-2 microglia cells were significantly up-regulated by exposure to moderate hypothermia. These findings further support the implication of RBM3 as a potential effector for hypothermia-induced neuroprotection.

Cell morphology, proliferation and motility, as well as mono- and heterotypic cell-to-cell interactions, are of increasing interest for in vitro experiments. However, tightly controlling culture conditions whilst simultaneously monitoring the same set of cells is complicated. Moreover, video-microscopy of distinct cells or areas of cells over a prolonged period of time represents a technical challenge. The SlideObserver was designed for cinemicrography of cells in co-and monoculture. The core elements of the system are the SlideReactors, miniaturised hollow fibre-based bioreactors operated in closed perfusion loops. Within the SlideReactors, cells can be cultured under adaptable conditions as well as in direct- and indirect co-culture. The independent perfusion loops enable controlled variation of parameters such as medium, pH, and oxygenation. A combined automated microscope stage and camera set-up allows for micrograph acquisition of multiple user-defined regions of interest within the bioreactor units. For proof of concept, primary cells (HUVEC, human hepatocytes) and cell lines (HuH7, THP-1) were cultured under stable and varying culture conditions, as well as in mono- and co-culture. The operational system enabled non-stop imaging and automated control of process parameters as well as elective manipulation of either reactor. As opposed to non-perfused culture systems or comparable devices for cinemicrographic analysis, the SlideObserver allows simultaneous morphological monitoring of an entire culture of cells in multiple bioreactors.

Labeling of hepatocytes with micron-sized iron oxide particles (MPIOs) enables cell detection using clinical magnetic resonance equipment. For clinical applications, large numbers of cells must be labeled in a simple and rapid manner and have to be applied in suspension. However, all existing protocols are based on adhesion culture labeling with subsequent resuspension, only suitable for small experimental settings. The aim of this study was to investigate the feasibility of preparing MPIO-labeled primary human hepatocytes in a temporary suspension culture. Human hepatocytes were isolated from 16 donors and labeled with MPIOs in suspension, using the Rotary Cell Culture System. Particle incorporation was investigated by light and electron microscopy. Cells were compared with adhesion culture-labeled and subsequently enzymatically resuspended cells. During a period of 5 days, hepatocyte-specific parameters of cell damage (aspartate aminotransferase and alanine aminotransferase) and metabolic activity (urea and albumin) were analyzed (n = 7). Suspension cultures showed a higher outcome in cell recovery compared with the conventional labeling method. When incubated with 180 particles/viable cell for 4 h, the mean particle uptake was 28.8 particles/cell at a labeling efficiency of 95.1%. Labeling in suspension had no adverse effects on cell integrity or metabolic activity. We conclude that labeling of human hepatocytes in suspension is feasible and simple and may serve future large-scale processing of cells.

Patients with cyanotic congenital cardiac disease often develop major aortopulmonary collaterals. Vascular endothelial growth factor is a key promoter of angiogenesis. Its soluble receptor-1 acts as a potent antagonist. We studied 30 infants with cyanotic congenital cardiac disease and 27 infants with acyanotic congenital cardiac disease. Central venous plasma vascular endothelial growth factor and soluble vascular endothelial growth factor receptor-1 levels were measured before, and 24 and 96 hours after surgery. There was no difference between plasma vascular endothelial growth factor levels in infants with cyanotic and those with acyanotic congenital cardiac disease. In cyanotic infants, the soluble vascular endothelial growth factor receptor-1 levels tended to be higher than in the acyanotic infants. In conclusion, there is no significant difference in the plasma levels of vascular endothelial growth factor and its soluble receptor-1 between infants with cyanotic and those with acyanotic congenital cardiac disease.

Despite the widespread interest in the clinical applications of hypothermia, the cellular mechanisms of hypothermia-induced neuroprotection have not yet been clearly understood. Therefore, the aim of this study was to elucidate the cellular effects of clinically relevant hypothermia and rewarming on the morphological and functional characteristics of microglia. Microglial cells were exposed to a dynamic cooling and rewarming protocol. For stimulation, microglial cells were treated with 1 microg/mL lipopolysaccharide (LPS). We found that hypothermia led to morphological changes from ramified to ameboid cell shapes. At 2 h after hypothermia and rewarming, microglial cells were again ramified with extended branches. Moreover, we found enhanced cell activation after rewarming, accompanied by increased phagocytosis and adenosine triphosphate consumption. Interestingly, hypothermia and rewarming led to a time-dependent significant up-regulation of the anti-inflammatory cytokines interleukin-10 and interleukin-1 receptor antagonist in stimulated microglial cells. This is in line with the reduced proliferation and time-dependent down-regulation of the pro-inflammatory cytokines tumor necrosis factor-alpha and monocyte chemotactic protein-1 in comparison to normothermic control cells after LPS stimulation. Furthermore, degradation of the inhibitor of the nuclear transcription factor-kappaB (IkappaB-alpha) was diminished and delayed under conditions of cooling and rewarming in LPS-stimulated microglial cells. Thus, our results show that hypothermia and rewarming activate microglial cells, increase phagocytosis and shift the balance of cytokine release in stimulated microglial cells towards the anti-inflammatory cytokines. This could be a new cellular mechanism of hypothermia-induced neuroprotection mediated by activated microglial cells.

IntroductionCongenital heart disease (CHD) is the most common birth defect. Studies on the development of children with CHD point towards deficits in motoric, cognitive and language development. However, most studies are cross-sectional and there is a gap in the knowledge concerning developmental trajectories, risk and protective factors and a lack of research concerning environmental predictors. Specifically, no studies have so far considered the importance of early caregiving experiences and child temperament for the development of children with CHD.MethodsIn a single-centre prospective cohort study, cognitive, motoric and language development of 180 children after corrective surgery for a simple transposition of the great arteries (TGA), tetralogy of Fallot (TOF) or ventricular septal defect (VSD) will be assessed at ages 12, 24 and 36 months with the Bayley Scales of Infant Development 3rd Edition (BSID-III). At age 12 months, a free-play video observation will be conducted to investigate the relationship between primary caregiver and child, and child temperament will be assessed with the Infant Behavior Questionnaire—Revised Short Version. Medical information will be obtained from patient records and demographic information via questionnaires.AnalysisFrequency and severity of developmental delays will be reported descriptively. Differences between groups (TGA, TOF, VSD) will be subjected to repeated-measures analysis across time points. Multiple regressions will be applied for the analysis of predictors at each time point. For the analysis of differential developmental trajectories, mixed-model analysis will be applied.Ethics and disseminationThe study has been approved by the local medical ethics committee. Written informed consent will be obtained from all participants. Parents have the option to be debriefed about BSID-III results after each assessment and about the study results after project completion. Results will be disseminated in peer-reviewed journals and presented at conferences.Trial registration numberDRKS00011006; Pre-results.

Systemic or brain-selective hypothermia is a well-established method for neuroprotection after brain trauma. There is increasing evidence that hypothermia exerts beneficial effects on the brain and may also support regenerative responses after brain damage. Here, we have investigated whether hypothermia influences neurite outgrowth in vitro via modulation of the post-injury cytokine milieu. Organotypic brain slices were incubated: deep hypothermia (2 h at 17 degrees C), rewarming (2 h up to 37 degrees C), normothermia (20 h at 37 degrees C). Neurite density and cytokine release (IL 1beta, IL-6, IL-10, and TNF-alpha) were investigated after 24 h. For functional analysis mice deficient in NT-3/NT-4 and TNF-alpha as well as the TNF-alpha inhibitor etanercept were used. Hypothermia led to a significant increase of neurite outgrowth, which was independent of neurotrophin signaling. In contrast to other cytokines investigated, TNF-alpha secretion by organotypic brain slices was significantly increased after deep hypothermia. Moreover, hypothermia-induced neurite extension was abolished after administration of the TNF-alpha inhibitor and in TNF-alpha knockout mice. We demonstrate that TNF-alpha is responsible for inducing neurite outgrowth in the context of deep hypothermia and rewarming. These data suggest that hypothermia not only exerts protective effects in the CNS but may also support neurite outgrowth as a potential mechanism of regeneration.

Background Hypothermia is used to preserve organs for transplantation and is the oldest method to protect organs during complex pediatric cardiac surgery. Loss of tissue function and tissue edema are common complications in children undergoing corrective cardiac surgery and heart transplantation. The present study was designed to examine the effects of methylprednisolone and tacrolimus on endothelial cell function and morphology after deep hypothermia and rewarming. Methods Human umbilical vein endothelial cells were pre-treated with methylprednisolone or tacrolimus, or both, incubated within a specially designed bioreactor or in monolayers, and then exposed to a dynamic cooling and rewarming protocol. Immunocytochemistry, time-lapse video microscopy, cell permeability and adherence assays, and Western blot analysis were performed. Results Confluent endothelial cells exposed to hypothermia displayed elongated cell shapes with intercellular gap formation, increased endothelial cell-layer permeability, and loss in adherence. Upon rewarming, however, endothelial cell integrity was restored. Opening and closing of intercellular gaps was dependent on extracellular signal-regulated kinase 1 and 2 (ERK 1/2) activation and connexin 43 expression. The combined treatment with methylprednisolone and tacrolimus inhibited these hypothermia-induced changes. Conclusions These results suggest that methylprednisolone and tacrolimus inhibit hypothermia-induced endothelial gap formation by phosphorylated ERK 1/2 inhibition and connexin 43 stabilization. Application of combined drugs that affect multiple targets may therefore be considered as a possible new therapeutic strategy to prevent endothelial dysfunction after hypothermia and rewarming.

Hypothermia is a standard method for organ protection during cardiac surgery in children. However, the mechanisms of hypothermia-induced cell protection have not yet been clearly established. Therefore, the aim of our studies was to elucidate molecular effects of clinically relevant mild and deep hypothermia on endothelial cells. The endothelium plays a pivotal role in the interaction between blood cells and actively participates in complex inflammatory events. We isolated primary human umbilical vein endothelial cells (HUVEC) and investigated cell viability, proliferation and inflammatory characteristics after TNF-alpha stimulation under mild (32 degrees C) and deep (17 degrees C) hypothermia in comparison to normothermia (37 degrees C). As a protective mechanism of endothelial cells kept under hypothermic conditions we found a significant upregulation of the antiapoptotic protein Bcl-2, resulting in the same cell viability under hypothermic conditions. Unexpectedly we demonstrated significantly higher IL-6 release after 6h of mild hypothermia. In contrast, hypothermia diminished inflammatory chemokines such as IL-8, MCP-1 and COX-2 protein expression which could lead to reduced leukocyte recruitment under hypothermia. Underlying mechanisms of this downregulation were found to be reduced ERK 1/2 phosphorylation and incomplete IkappaB-alpha degradation resulting in reduced NFkappaB-dependent proinflammatory gene expression. The upregulation of Bcl-2 protein and the higher IL-6 release after 6h of mild hypothermia are new and interesting cellular mechanisms of hypothermia in endothelial cell biology. Both factors may play a major role as cell protective mechanisms in hypothermia.

Brain protection is essential during neonatal and pediatric cardiac surgery. Deep hypothermia is still the most important method for achieving neuroprotection during cardiopulmonary bypass. Previously, we could demonstrate that deep hypothermia induces substantial cytotoxicity in brain cells as well as increased release of the pro-inflammatory cytokine interleukin-6 (IL-6), which plays an important role in neuroprotection and neuroregeneration. Deep hypothermia is also associated with increased levels of the astrocytic protein S100B in the serum and cerebrospinal fluid of patients. Since S100B may modulate pro-inflammatory cytokines and may stimulate neurite outgrowth, we have tested the hypothesis that nanomolar concentrations of S100B may increase IL-6 release from brain cells and support axonal outgrowth from organotypic brain slices under hypothermic conditions. S100B administration substantially reduced neuronal and glial cytotoxicity under hypothermic conditions. In the presence of S100B hypothermia-induced IL-6 release in primary astrocytes was significantly increased but reduced in BV-2 microglial cells and primary neurons. Surprisingly, deep hypothermia increased axonal outgrowth from brain slices and--in contrast to our hypothesis--this hypothermia-induced neurite outgrowth was inhibited by S100B. These data suggest that S100B differentially influences cytokine release and cytotoxicity from distinct brain cells and may inhibit neuroregeneration by suppressing hypothermia-induced axonal outgrowth.

A multicenter study of the HeartWare ventricular assist device in small children Oliver Miera, MD, Richard Kirk, MD, Holger Buchholz, MD, Katharina R.L. Schmitt, MD, Christina VanderPluym, MD, Ivan M. Rebeyka, MD, Neil Wrightson, MD, Felix Berger, MD, Massimo Griselli, MD, and Jennifer Conway, MD From the Department of Congenital Heart Disease/Pediatric Cardiology, Deutsches Herzzentrum Berlin, Berlin, Germany; Department of Pediatric Cardiology, Freeman Hospital, Newcastle Upon Tyne, UK; Stollery Children’s Hospital, University of Alberta, Edmonton, Alberta, Canada; and the Department of Cardiology, Boston Children’s Hospital, Boston, Massachusetts, USA