Outcomes of hypoplastic left heart syndrome in low-birth-weight patients

Impact of Maternal-Fetal Environment on Outcomes Following the Hybrid Procedure in the Single Ventricle Population

Treatment of infants with hypoplastic left heart syndrome (HLHS) remains challenging, and those affected remain with significant risks for mortality and morbidity throughout their lifetimes. The maternal-fetal environment (MFE) has been shown to affect outcomes for infants with HLHS after the Norwood procedure. The hybrid procedure, comprised of both catheterization and surgical components, is a less invasive option for initial intervention compared to the Norwood procedure. It is unknown how the MFE impacts outcomes following the hybrid procedure. This is a single-center, retrospective study of infants born with HLHS who underwent hybrid palliation from January 2009 to August 2021. Predictor variables analyzed included fetal, maternal, and postnatal factors. The primary outcome was mortality prior to Stage II palliation. We studied a 144-subject cohort. There was a statistically significant difference in mortality prior to stage II palliation in infants with prematurity, small for gestational age, and aortic atresia subtype (p < 0.001, p = 0.009, and p = 0.008, respectively). There was no difference in mortality associated with maternal diabetes, hypertension, obesity, smoking or illicit drug use, or advanced maternal age. State and national area deprivation index scores were associated with increased risk of mortality in the entire cohort, such that infants born in areas with higher deprivation had a higher incidence of mortality. Several markers of an impaired MFE, including prematurity, small for gestational age, and higher deprivation index scores, are associated with mortality following hybrid palliation. Individual maternal comorbidities were not associated with higher mortality. The MFE may be a target for prenatal counseling and future interventions to improve pregnancy and neonatal outcomes in this population.

Mortality and Heart Transplantation After Hybrid Palliation of Hypoplastic Left Heart Syndrome: A Systematic Review and Meta-Analysis

BACKGROUND

Newborns with hypoplastic left heart syndrome (HLHS) who are considered at increased risk for death following Norwood/Sano surgery often undergo hybrid palliation (HP) as initial surgery. We aimed to compile the HP experience in HLHS and its variants and assess the rates of, and risk factors for, death and heart transplantation.

METHODS

CINAHL, CINAHL PLUS, PubMed/MEDLINE, and SCOPUS were systematically searched for HP outcome studies of death or heart transplantation in HLHS between 1998 and 2022. Pooled incidence was estimated, and potential risk factors were identified using random-effects meta-analysis and reconstructed time-to-event data from Kaplan-Meier curves.

RESULTS

Thirty-three publications were included in our review. Overall, of 1,162 patients 417 died and 57 underwent heart transplantation, resulting in a combined outcome of 40.7%, (474/1,162). There was a trend toward decreasing mortality risk across the stages of palliation. Pooled mortality between HP and comprehensive stage 2 palliation was 25%, after stage 2 up to Fontan palliation was 16%, and 6% post-Fontan. The incidence of death or heart transplantation was higher in high-risk patients-43% died and 10% received heart transplantation.

CONCLUSION

Our systematic review and meta-analysis found high rates of death or heart transplantation in HP of HLHS patients between HP and Fontan surgeries. All patients should be closely followed during the initial interstage period, which is associated with the highest hazard. Prospective studies on appropriate patient selection, indications, and / or alternatives, as well as refining HP strategies for managing newborns with HLHS are needed to improve outcomes.

Infants less than or equal to 2.5 kg have increased mortality and worse motor neurodevelopmental outcomes at 2 years of age after Norwood-Sano palliation

Objectives

In infants with single-ventricle congenital heart disease, prematurity and low weight at the time of the Norwood operation are risk factors for mortality. Reports assessing outcomes (including neurodevelopment) post Norwood palliation in infants ≤2.5 kg are limited.

Methods

All infants who underwent a Norwood-Sano procedure between 2004 and 2019 were identified. Infants ≤2.5 kg at the time of the operation (cases) were matched 3:1 with infants >3.0 kg (comparisons) for year of surgery and cardiac diagnosis. Demographic and perioperative characteristics, survival, and functional and neurodevelopmental outcomes were compared.

Results

Twenty-seven cases (mean ± standard deviation: weight 2.2 ± 0.3 kg and age 15.6 ± 14.1 days at surgery) and 81 comparisons (3.5 ± 0.4 kg and age 10.9 ± 7.9 days at surgery) were identified. Post-Norwood, cases had a longer time to lactate ≤2 mmol/L (33.1 ± 27.5 vs 17.9 ± 12.2 hours, P < .001), longer duration of ventilation (30.5 ± 24.5 vs 18.6 ± 17.5 days, P = .005), greater need for dialysis (48.1% vs 19.8%, P = .007), and greater need for extracorporeal membrane oxygenation support (29.6% vs 12.3%, P = .004). Cases had significantly greater postoperative (in-hospital) (25.9% vs 1.2%, P < .001) and 2-year (59.2% vs 11.1%, P < .001) mortality. Neurodevelopmental assessment showed the following for cases versus comparisons, respectively: cognitive delay (18.2% vs 7.9%, P = .272), language delay (18.2% vs 11.1%, P = .505), and motor delay (27.3% vs 14.3%, P = .013).

Conclusions

Infants ≤2.5 kg at Norwood-Sano palliation have significantly increased postoperative morbidity and mortality up to 2-year follow-up. Neurodevelopmental motor outcomes were worse in these infants. Additional studies are warranted to assess the outcome of alternative medical and interventional treatment plans in this patient population.

Hypoplastic Left Heart Syndrome: About a Postnatal Death

BACKGROUND

Hypoplastic left heart syndrome (HLHS) is a congenital heart disease that is associated with high mortality rates in the early neonatal period and during surgical treatments. This is mainly due to missed prenatal diagnosis, delayed diagnostic suspicion, and consequent unsuccessful therapeutic intervention.

CASE REPORT

twenty-six hours after birth, a female newborn died of severe respiratory failure. No cardiac abnormalities and no genetic diseases had been evidenced or documented during intrauterine life. The case became of medico-legal concern for the assessment of alleged medical malpractice. Therefore, a forensic autopsy was performed.

RESULTS

the macroscopic study of the heart revealed the hypoplasia of the left cardiac cavities with the left ventricle (LV) reduced to a slot and a right ventricular cavity that simulated the presence of a single and unique ventricular chamber. The predominance of the left heart was evident.

CONCLUSIONS

HLHS is a rare condition that is incompatible with life, with very high mortality from cardiorespiratory insufficiency that occurs soon after birth. The prompt diagnosis of HLHS during pregnancy is crucial in managing the disease with surgery.

Early Mortality in Infants Born with Neonatally Operated Congenital Heart Defects and Low or Very-Low Birthweight: A Systematic Review and Meta-Analysis

Mortality outcomes of children with isolated neonatally operated congenital heart defects (CHDs) born with a low (LBW), moderately low (MLBW) or very-low birthweight (VLBW) remain ambiguous. We searched Medline and Embase (inception until October 2021) and included studies that evaluated early mortality. The risk of bias was assessed using the Critical Appraisal Skills Program cohort checklist. Meta-analysis involved random-effects models. We explored variability in mortality across birthweight subgroups, CHD types, and study designs. From 2035 reports, we included 23 studies in qualitative synthesis, and the meta-analysis included 11 studies (1658 CHD cases), divided into 30 subcohorts. The risk of bias was low in 4/11 studies included in the meta-analysis. Summary mortality before discharge or within one month after surgery was 37% (95%CI 27-47). Early mortality varied by birthweight (VLBW 56%, MLBW 15%, LBW 16%; p = 0.003) and CHD types (hypoplastic left heart syndrome (HLHS) 50%, total anomalous pulmonary venous return (TAPVR) 47%, transposition of the great arteries (TGA) 34%, coarctation of the aorta (CoA) 16%; p = 0.13). Mortality was higher in population-based studies (49% vs. 10%; p = 0.006). One-third of infants born with neonatally operated isolated CHDs and LBW, MLBW, or VLBW died within 30 days after surgery. Mortality varied across infant and study characteristics. These results may help clinicians assess neonatal prognosis. PROSPERO registration CRD42020170289.

Premature and Extracorporeal Life Support: Is it Time? A Systematic Review

Early preterm birth < 34 gestational weeks (GA) and birth weight (BW) <2 kg are relative contraindications for extracorporeal membrane oxygenation (ECMO). However, with improved technology, ECMO is presently managed more safely and with decreasing complications. Thus, these relative contraindications may no longer apply. We performed a systematic review to evaluate the existing literature on ECMO in early and late (34-37 GA) prematurity focusing on survival to hospital discharge and the complication intracranial hemorrhage (ICH). Data sources: MEDLINE, PubMed, Web of Science, Embase, and the Cochrane Database. Only publications in the English language were evaluated. Of the 36 included studies, 23 were related to ECMO support for respiratory failure, 10 for cardiac causes, and four for congenital diaphragmatic hernia (CDH). Over the past decades, the frequency of ICH has declined (89-21%); survival has increased in both early prematurity (25-76%), and in CDH (33-75%), with outcome similar to late prematurity (48%). The study was limited by an inherent risk of bias from overlapping single-center and registry data. Both the risk of ICH and death have decreased in prematurely born treated with ECMO. We challenge the 34 week GA time limit for ECMO and propose an international task force to revise current guidelines. At present, gestational age < 34 weeks might no longer be considered a contraindication for ECMO in premature neonates.

Being Born with a Single Cardiac Ventricle: What Do We Tell Prospective Parents

Being born with a single ventricle remains one of the most extreme congenital cardiac conditions. It encompasses a wide variety of lesions characterized by the existence of one small ventricular cavity. To allow survival, these patients must undergo a series of operations in the first years of life. It was long considered that the success of these interventions would be short-lived and that only a few of these patients would live beyond adulthood. The last decade has seen publication of multiple large outcomes researches on this population, and we now realize that its survival is longer than expected, but with a considerable burden of disease. As a consequence, the size of this single ventricle population is growing rapidly. As primary conveyer of the information on the future of these babies, obstetricians need to be aware of these changes in perspective. This article is protected by copyright. All rights reserved.

Placental and fetal characteristics of the Ohia mouse line recapitulate outcomes in human hypoplastic left heart syndrome

Congenital heart defects (CHDs) are the most common birth defect worldwide. The morbidity and mortality associated with these defects is compounded by increased frequency of fetal growth abnormalities. In the Ohia mouse model of hypoplastic left heart syndrome (HLHS), the double homozygous genotype is embryonically lethal at mid-pregnancy; a time in which optimal establishment of the placenta is crucial to fetal survival. We aimed to characterize placental and fetal growth and development in the double heterozygous genotype (Sap130^m/+Pcdha9^m/+). There was a shift in frequency of fetuses with reduced weight near term in the Sap130^m/+Pcdha9^m/+ fetuses compared to wildtype, driven by lower fetal weight in male fetuses compared to female. This shift in fetal weight distribution in the Sap130^m/+Pcdha9^m/+ fetuses was associated with reduced labyrinth region area (P < 0.001) and reduced fetal capillary density (P < 0.001) in the placentas, the latter being significantly lower in male Sap130^m/+Pcdha9^m/+ placentas compared to female. mRNA expression of several nutrient transporters was also lower in placentas from males compared to placentas from females, irrespective of genotype. Overall, this data shows that whilst the double heterozygous fetuses do not carry heart defects, placental development and function is impaired, particularly in males. Such differences are similar to findings in studies of human placentas and highlights the importance of this mouse model in continuing to understand the developmental links and disruptions to the heart-placenta axis.

Children Born with Congenital Heart Defects and Growth Restriction at Birth: A Systematic Review and Meta-Analysis

Newborns with congenital heart defects tend to have a higher risk of growth restriction, which can be an independent risk factor for adverse outcomes. To date, a systematic review of the relation between congenital heart defects (CHD) and growth restriction at birth, most commonly estimated by its imperfect proxy small for gestational age (SGA), has not been conducted. Objective: To conduct a systematic review and meta-analysis to estimate the proportion of children born with CHD that are small for gestational age (SGA). Methods: The search was carried out from inception until 31 March 2019 on Pubmed and Embase databases. Studies were screened and selected by two independent reviewers who used a predetermined data extraction form to obtain data from studies. Bias was assessed using the Critical Appraisal Skills Programme (CASP) checklist. The database search identified 1783 potentially relevant publications, of which 38 studies were found to be relevant to the study question. A total of 18 studies contained sufficient data for a meta-analysis, which was done using a random effects model. Results: The pooled proportion of SGA in all CHD was 20% (95% CI 16%–24%) and 14% (95% CI 13%–16%) for isolated CHD. Proportion of SGA varied across different CHD ranging from 30% (95% CI 24%–37%) for Tetralogy of Fallot to 12% (95% CI 7%–18%) for isolated atrial septal defect. The majority of studies included in the meta-analysis were population-based studies published after 2010. Conclusion: The overall proportion of SGA in all CHD was 2-fold higher whereas for isolated CHD, 1.4-fold higher than the expected proportion in the general population. Although few studies have looked at SGA for different subtypes of CHD, the observed variability of SGA by subtypes suggests that growth restriction at birth in CHD may be due to different pathophysiological mechanisms.

Survival After Norwood Procedure in High-Risk Patients

BACKGROUND

Multiple single-ventricle populations are noted to be at increased risk for mortality after the Norwood procedure. Preoperative risk factors include low birth weight, restrictive/intact atrial septum, obstructed pulmonary veins, ventricular dysfunction, and atrioventricular valve regurgitation. We report outcomes of the Norwood procedure in standard- and high-risk patients in the recent era.

METHODS

All patients born with hypoplastic left heart syndrome between 2006 and 2016 who underwent a Norwood procedure at our institution were included. Patient data were retrospectively reviewed, and Kaplan-Meier analysis was used to evaluate survival between groups.

RESULTS

The cohort included 177 patients. Fifty patients were determined high-risk preoperatively: low birth weight (n = 18), ventricular dysfunction/atrioventricular valve regurgitation (n = 13), intact or restrictive atrial septum/obstructed anomalous pulmonary venous return (n = 14), and multiple factors (n = 5). There were 2 (1.6%) deaths before Glenn in the standard-risk group, with a total of 10 (20%) from the high-risk groups (P < .0001). Survival at 1 year differed greatly between groups, with highest being standard risk at 89% and lowest in the intact septum/obstructed veins group at 54%. The difference between groups in long-term survival was significant (P < .001).

CONCLUSIONS

Outcomes after the Norwood procedure have improved for standard-risk patients. Those with preoperative risk factors account for most of the early deaths after the Norwood procedure. This high-risk status does not resolve after Glenn, because longer-term survival continues to diverge from the standard-risk group.

Prognostic Risk Analyses for Postcardiotomy Extracorporeal Membrane Oxygenation in Children: A Review of Early and Intermediate Outcomes

We evaluated the morbidity and mortality of children requiring postcardiotomy extracorporeal membrane oxygenation (ECMO) to determine independent factors affecting early and intermediate outcomes. Between January 2002 and December 2015, 79 instances of ECMO after cardiac surgery in 73 children were retrospectively reviewed. Follow-up was completed in December 2016. Predictive risk analyses were employed concerning weaning of ECMO, hospital discharge, and mortality after discharge. Age and weight were 14.9 ± 25.6 months and 7.0 ± 5.3 kg, respectively. Median support time was 8.3 ± 4.4 days. Sixty-seven (85%) were successfully weaned off ECMO and 48 (61%) survived to hospital discharge. Multi-variate logistic regression analysis identified the first day to obtain negative fluid balance after initiation of support (adjusted odds ratio = 0.42), high serum lactate levels (0.97), and high total bilirubin (0.84) during support as significant independent factors associated with successful separation from ECMO. The first day of negative fluid balance (0.65) after successful decannulation was an independent risk factor for survival to hospital discharge. After hospital discharge, actuarial 1-year, 5-year, and 10-year survival rates were 94%, 78%, and 78%, respectively. Low weight increased the risk of death after hospital discharge by a multi-variate Cox hazard model. High serum lactate, high serum bilirubin, and unable to obtain early negative fluid balance during support impacted mortality of decannulation. Obtaining a late negative fluid balance in post-ECMO were independent risk factors for death after successful weaning. Low weight affected intermediate outcomes.

Effects of Gestational Age on Early Survivability in Neonates With Hypoplastic Left Heart Syndrome

Prematurity increases pre- and postoperative mortality in children with congenital heart disease. There are no large, multicentered, studies that have evaluated this relation specifically in neonates with hypoplastic left heart syndrome (HLHS). We sought to determine the impact of gestational age (GA) on survival to Stage 1 palliation surgery and hospital discharge in infants with HLHS. We reviewed data from 1,913 neonates with HLHS born at or transferred to a Vermont Oxford Network expanded member hospital in the United States from 2009 to 2014. Demographic, diagnostic, and surgical codes, and outcome data within the Vermont Oxford Network database were used to determine the effect of GA and birth weight on survival to Stage 1 palliation surgery and hospital discharge. Risk models were developed controlling for common confounders to determine the relative risk of GA on the observed outcomes. These data demonstrate that, when compared with 39-week infants, those born at earlier GA were less likely to survive until surgery; <34 weeks adjusted risk ratio (ARR) for survival: 0.47 (95% confidence interval 0.37 to 0.60), 34 to 35 weeks ARR 0.73 (0.62 to 0.87), and 36 to 37 weeks ARR 0.88 (0.83 to 0.94). Higher GA also positively correlated with survival to hospital discharge, although there was no difference in 34 to 35-week infants and 36 to 37-week infants. In conclusion, these data show that GA was an independent risk factor for survival to Stage 1 palliation surgery and survival to hospital discharge. However, there is no significant difference in survival to hospital discharge between infants born in 34 to 37 weeks gestation.

Extracorporeal membrane oxygenation, Berlin, and ventricular assist devices: a primer for the cardiologist

PURPOSE OF REVIEW

Mechanical circulatory support (MCS) has become an indispensable tool in the management of children with impending respiratory and cardiac failure. Though extracorporeal membrane oxygenation (ECMO) was classically the only form of support available to pediatric patients, considerable advances have allowed ventricular assist devices (VADs) to become increasingly utilized in children. This review provides an update of recent advances in ECMO and VAD management in children.

RECENT FINDINGS

The options for mechanical support in infants and small children with end-stage heart failure are limited. As such, the greatest advances in the past decade have come in the successful adoption of the Berlin Heart EXCOR device, with a marked improvement in survival to transplant over ECMO. Further advances have been made in the use of adult VADs in children. For instance, the HeartWare HVAD has been utilized in children as young as 3 years of age, despite being designed for use in adult patients.

SUMMARY

The availability of mechanical support options for children remains limited to ECMO and a small number of VADs. While outcomes of VAD support in pediatric patients have been promising, further study in smaller and more complex pediatric patients is necessary.

Influence of weight at the time of first palliation on survival in patients with a single ventricle

BACKGROUND

Numerous advances in surgical techniques and understanding of single-ventricle physiology have resulted in improved survival. We sought to determine the influence of various demographic, perioperative, and patient-specific factors on the survival of single-ventricle patients following stage 1 palliation at our institution.

METHODS

We conducted a retrospective study of all single-ventricle patients who had undergone staged palliation at our institution over an 8-year period. Data were collected from the Society of Thoracic Surgeons Congenital Heart Surgery database and from patient charts. Information on age, weight at stage 1 palliation, prematurity, genetic abnormalities, non-cardiac anomalies, ventricular dominance, and type of palliation was collected. Information on mortality and unplanned reinterventions was also collected.

RESULTS

A total of 72 patients underwent stage 1 palliation over an 8-year period. There were 12 deaths before and one death after stage 2 palliation. There was no hospital mortality following Glenn or Fontan procedures. On univariate analysis, low weight at the time of stage 1 palliation and prematurity were found to be risk factors for mortality following stage 1 palliation. However, multivariable Cox regression analysis revealed weight at stage 1 palliation to be a strong predictor of mortality. The type of stage 1 palliation did not have any influence on the outcome. No difference in survival was noted following the Glenn procedure.

CONCLUSION

Low weight has a deleterious impact on survival following stage 1 palliation. This is mitigated by stage 2 palliation. The type of stage 1 palliation itself has no bearing on the outcome.

Interstage Weight Gain Is Associated With Survival After First-Stage Single-Ventricle Palliation

BACKGROUND

Low birth and operative weight have been identified as risk factors for death after first-stage single-ventricle palliation. We hypothesize that weight gain after the first-stage operation is associated with transplant-free interstage survival to admission for the second-stage operation.

METHODS

We used historical data from the National Pediatric Cardiology Quality Improvement Collaborative database to conduct a longitudinal study to assess the association between weight gain and transplant-free interstage survival. The primary predictor was weight gain. The primary outcome was transplant-free survival. We constructed a repeated-measures logistic regression model using the general estimating equation method to examine the association between weight gain and transplant-free interstage survival.

RESULTS

The study population included 1,501 infants who were discharged alive from the first-stage single-ventricle palliation between June 2008 and January 2015. Patients who underwent a hybrid operation (n = 132) or were lost to follow-up (n = 11) were excluded. Transplant-free interstage survival was 90% (1,228 of 1,358). The mean weight gain was 2.5 (SD, 1.0) kg. Adjusted for age at the time of each measurement, the number of measurements, age at discharge from the first-stage operation, sex, diagnosis, postoperative arrhythmia, postoperative complications, and discharge antibiotic therapy, each 100-g increase in weight was associated with an odds ratio of transplant-free interstage survival of 1.03 (95% confidence limit, 1.01, 1.05).

CONCLUSIONS

After first-stage single-ventricle palliation, interstage weight gain is significantly associated with transplant-free interstage survival.

Extracorporeal Membrane Oxygenation in a 1,360-g Premature Neonate after Repairing Total Anomalous Pulmonary Venous Return

With advancements in complex repairs in neonates with complicated congenital heart diseases, extracorporeal membrane oxygenation (ECMO) has been increasingly used as cardiac support. ECMO has also been increasingly used for low birth weight (LBW) or very low birth weight (VLBW) neonates. However, since prematurity and LBW are risk factors for ECMO, the appropriate indications for neonates with LBW, especially VLBW, are under dispute. We report a case of ECMO performed in a 1,360-g premature infant with VLBW due to cardiopulmonary bypass weaning failure after repairing infracardiac total anomalous pulmonary venous return.

Perinatal Decision Making for Preterm Infants with Congenital Heart Disease: Determinable Risk Factors for Mortality

For premature infants with congenital heart disease (CHD), it may be unclear when the burdens of treatment outweigh potential benefits. Parents may thus have to choose between comfort care at birth and medical stabilization until surgical repair is feasible. Better defined outcome data, including risk factors for mortality, are needed to counsel expectant parents who are considering intensive care for premature infants with CHD. We sought to evaluate outcomes in this population to inform expectant parents considering intensive versus palliative care at birth. We performed a retrospective cohort study of infants born <34 weeks who received intensive care with critical or moderately severe CHD predicted to require surgery in the neonatal period or the first 6 months of life. 46 % of 54 infants survived. Among non-survivors, 74 % died prior to surgery (median age 24 days). Of the infants that underwent surgery, 75 % survived. Survival was lower among infants <32 weeks gestational age (GA) (p = 0.013), with birth weight (BW) <1500 g (p = 0.011), or with extra-cardiac anomalies (ECA) (p = 0.015). GA and ECA remained significant risk factors for mortality in multiple logistic regression analysis. In summary, GA < 32 weeks, BW < 1500 g, and ECA are determinable prenatally and were significant risk factors for mortality. The majority of infants who survived to cardiac intervention survived neonatal hospitalization, whereas most of the infants who died did so prior to surgery. For some expectant parents, this early declaration of mortality may support a trial of intensive care while avoiding burdensome interventions.

Management of the Preterm Infant with Congenital Heart Disease

The premature neonate with congenital heart disease (CHD) represents a challenging population for clinicians and researchers. The interaction between prematurity and CHD is poorly understood; epidemiologic study suggests that premature newborns are more likely to have CHD and that fetuses with CHD are more likely to be born premature. Understanding the key physiologic features of this special patient population is paramount. Clinicians have debated optimal timing for referral for cardiac surgery, and management in the postoperative period has rapidly advanced. This article summarizes the key concepts and literature in the care of the premature neonate with CHD.

Ductal stenting using side-branch cell dilation for aortic coarctation in high-risk patients with hypoplastic left heart syndrome

For high-risk neonates with hypoplastic left heart syndrome (HLHS) undergoing Norwood operation, the strategy of bilateral pulmonary artery banding and ductal stenting is risky in case of coarctation of the aorta (CoA), often resulting in death. Therefore, we devised a new method of ductal stenting with side-branch cell dilation, which could overcome the constriction of the ductal arch with CoA in two HLHS patients. This is the first report that presents this method and the results. © 2015 Wiley Periodicals, Inc.

Extracorporeal Life Support for Pediatric Heart Failure

Extracorporeal life support (ECLS) represents an essential component in the treatment of the pediatric patient with refractory heart failure. Defined as the use of an extracorporeal system to provide cardiopulmonary support, ECLS provides hemodynamic support to facilitate end-organ recovery and can be used as a salvage therapy during acute cardiorespiratory failure. Support strategies employed in pediatric cardiac patients include bridge to recovery, bridge to therapy, and bridge to transplant. Advances in extracorporeal technology and refinements in patient selection have allowed wider application of this therapy in pediatric heart failure patients.

ECLS in Pediatric Cardiac Patients

Extracorporeal life support (ECLS) is an important device in the management of children with severe refractory cardiac and or pulmonary failure. Actually, two forms of ECLS are available for neonates and children: extracorporeal membrane oxygenation (ECMO) and use of a ventricular assist device (VAD). Both these techniques have their own advantages and disadvantages. The intra-aortic balloon pump is another ECLS device that has been successfully used in larger children, adolescents, and adults, but has found limited applicability in smaller children. In this review, we will present the "state of art" of ECMO in neonate and children with heart failure. ECMO is commonly used in a variety of settings to provide support to critically ill patients with cardiac disease. However, a strict selection of patients and timing of intervention should be performed to avoid the increase in mortality and morbidity of these patients. Therefore, every attempt should be done to start ECLS "urgently" rather than "emergently," before the presence of dysfunction of end organs or circulatory collapse. Even though exciting progress is being made in the development of VADs for long-term mechanical support in children, ECMO remains the mainstay of mechanical circulatory support in children with complex anatomy, particularly those needing rapid resuscitation and those with a functionally univentricular circulation. With the increase in familiarity with ECMO, new indications have been added, such as extracorporeal cardiopulmonary resuscitation (ECPR). The literature supporting ECPR is increasing in children. Reasonable survival rates have been achieved after initiation of support during active compressions of the chest following in-hospital cardiac arrest. Contraindications to ECLS have reduced in the last 5 years and many centers support patients with functionally univentricular circulations. Improved results have been recently achieved in this complex subset of patients.

Abnormal development of thalamic microstructure in premature neonates with congenital heart disease

Preterm birth is associated with alteration in corticothalamic development, which underlies poor neurodevelopmental outcomes. Our hypothesis was that preterm neonates with CHD would demonstrate abnormal thalamic microstructure when compared to critically ill neonates without CHD. A secondary aim was to identify any association between thalamic microstructural abnormalities and perioperative clinical variables. We compared thalamic DTI measurements in 21 preterm neonates with CHD to two cohorts of neonates without CHD: 28 term and 27 preterm neonates, identified from the same neonatal intensive care unit. Comparison was made with three other selected white matter regions using ROI manual-based measurements. Correlation was made with post-conceptional age and perioperative clinical variables. In preterm neonates with CHD, there were age-related differences in thalamic diffusivity (axial and radial) compared to the preterm and term non-CHD group, in contrast to no differences in anisotropy. Contrary to our hypothesis, abnormal thalamic and optic radiation microstructure was most strongly associated with an elevated first arterial blood gas pO2 and elevated preoperative arterial blood gas pH (p < 0.05). Age-related thalamic microstructural abnormalities were observed in preterm neonates with CHD. Perinatal hyperoxemia and increased perioperative serum pH were associated with abnormal thalamic microstructure in preterm neonates with CHD. This study emphasizes the vulnerability of thalamocortical development in the preterm neonate with CHD.

Neoaortic thrombus after Norwood procedure: complication of extracorporeal life support?

Hypoplastic left heart syndrome is the most common diagnosis among infants requiring cardiac extracorporeal life support (ECLS) in the neonatal period, with more than half of patients experiencing an ECLS-related complication. We present a case of nearly obstructing neoaortic thrombus during ECLS occurring in the early postoperative period after modified Norwood palliation of hypoplastic left heart syndrome. Stasis within the neoaortic root due to the increased ventricular afterload associated with venoarterial ECLS may have potentiated this complication. Echocardiographic monitoring and early cardiac catheterization while on ECLS enabled prompt diagnosis and timely surgical correction.

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.

Outcomes of cardiac surgery in patients weighing <2.5 kg: affect of patient-dependent and -independent variables

OBJECTIVE

A recent Society of Thoracic Surgeons database study showed that low weight (<2.5 kg) at surgery was associated with high operative mortality (16%). We sought to assess the outcomes after cardiac repair in patients weighing <2.5 kg versus 2.5 to 4.5 kg in an institution with a dedicated neonatal cardiac program and to determine the potential role played by prematurity, the Society of Thoracic Surgeons-European Association for Cardio-Thoracic Surgery (STAT) risk categories, uni/biventricular pathway, and surgical timing.

METHODS

We analyzed the outcomes (hospital mortality, early reintervention, postoperative length of stay, mortality [at the last follow-up point]) in patients weighing <2.5 kg at surgery (n = 146; group 1) and 2.5 to 4.5 kg (n = 622; group 2), who had undergone open or closed cardiac repairs from January 2006 to December 2012 at our institution. The statistical analysis was stratified by prematurity, STAT risk category, uni/biventricular pathway, and usual versus delayed surgical timing. Univariate versus multivariate risk analysis was performed. The mean follow-up was 21.6 ± 25.6 months.

RESULTS

Hospital mortality in group 1 was 10.9% (n = 16) versus 4.8% (n = 30) in group 2 (P = .007). The postoperative length of stay and early unplanned reintervention rate were similar between the 2 groups. Late mortality in group 1 was 0.7% (n = 1). In group 1, early outcomes were independent of the STAT risk category, uni/biventricular pathway, or surgical timing compared with group 2. A lower gestational age at birth was an independent risk factor for early mortality in group 1.

CONCLUSIONS

A dedicated multidisciplinary neonatal cardiac program can yield good outcomes for neonates and infants weighing <2.5 kg independently of the STAT risk category and uni/biventricular pathway. A lower gestational age at birth was an independent risk factor for hospital mortality.

Extracorporeal life support for the neonatal cardiac patient: outcomes and new directions

Extracorporeal life support is an important therapy for neonates with life-threatening cardiopulmonary failure. Utilization of extracorporeal life support in neonates with congenital heart disease has increased dramatically during the past three decades. Despite increased usage, overall survival in these patients has changed very little and extracorporeal life support-related morbidity, including bleeding, neurologic injury, and renal failure, remains a major problem. Although survival is lower and neurologic complications are higher in premature infants than term infants, cardiac extracorporeal life support including extracorporeal cardiopulmonary resuscitation is effective in preventing death in many of these high-risk patients. Miniaturized ventricular assist devices and compact integrated extracorporeal life support systems are being developed to provide additional therapeutic options for neonates.

Analysis of preoperative condition and interstage mortality in Norwood and hybrid procedures for hypoplastic left heart syndrome using the Aristotle scoring system

OBJECTIVE

The 'hybrid procedure', consisting of surgical banding of the pulmonary arteries with intraoperative stenting of the arterial duct, was developed as primary palliation in hypoplastic left heart syndrome (HLHS), avoiding the risks of cardiopulmonary bypass. In many centres, it is reserved for low birth weight, premature or unstable neonates; however, its role in such high risk cases of HLHS has yet to be defined.

METHODS

The preoperative condition of all patients with HLHS who underwent either the hybrid or the Norwood procedure for HLHS between 2005-2011 was analysed retrospectively, using a modified comprehensive Aristotle score. We then compared operative, interstage and 1 year mortalities between the groups after Aristotle adjustment via Cox proportional hazards analyses.

RESULTS

Of 138 patients with HLHS, 27 had hybrid and 111 Norwood procedures. The hybrid group had significantly higher Aristotle scores (mean 4.1 vs 1.8; p<0.001); however, there was no significant difference in mortality at any stage. At 1 year, the overall unadjusted survival among Norwood and hybrid patients was 58.6% and 51.9%, respectively, yielding an Aristotle adjusted hazard ratio for mortality among hybrid patients of 1.09 (95% CI 0.56 to 2.11, p=0.80).

CONCLUSIONS

Applying a hybrid approach to high risk patients with HLHS produces a comparable early and interstage mortality risk to lower risk patients undergoing the Norwood procedure. Prospective studies are needed to establish whether the hybrid procedure is a viable alternative to the Norwood procedure in all HLHS patients in terms of both mortality and long term morbidity.

Abnormal cerebral microstructure in premature neonates with congenital heart disease

BACKGROUND AND PURPOSE

Abnormal cerebral microstructure has been documented in term neonates with congenital heart disease, portending risk for injury and poor neurodevelopmental outcome. Our hypothesis was that preterm neonates with congenital heart disease would demonstrate diffuse cerebral microstructural abnormalities when compared with critically ill neonates without congenital heart disease. A secondary aim was to identify any association between microstructural abnormalities, white matter injury (eg, punctate white matter lesions), and other clinical variables, including heart lesions.

MATERIALS AND METHODS

With the use of tract-based spatial statistics, an unbiased, voxelwise method for analyzing diffusion tensor imaging data, we compared 21 preterm neonates with congenital heart disease with 2 cohorts of neonates without congenital heart disease: 28 term and 27 preterm neonates, identified from the same neonatal intensive care unit.

RESULTS

Compared with term neonates without congenital heart disease, preterm neonates with congenital heart disease had microstructural abnormalities in widespread regions of the central white matter. However, 42% of the preterm neonates with congenital heart disease had punctate white matter lesions. When neonates with punctate white matter lesions were excluded, microstructural abnormalities remained only in the splenium. Preterm neonates with congenital heart disease had similar microstructure to preterm neonates without congenital heart disease.

CONCLUSIONS

Diffuse microstructural abnormalities were observed in preterm neonates with congenital heart disease, strongly associated with punctate white matter lesions. Independently, regional vulnerability of the splenium, a structure associated with visual spatial function, was observed in all preterm neonates with congenital heart disease.

Staged palliation of hypoplastic left heart syndrome: trends in mortality, cost, and length of stay using a national database from 2000 through 2009

Staged surgical palliation has revolutionized the care of patients with hypoplastic left heart syndrome (HLHS), although the outcomes of survival and cost at a national level remain unclear. This study sought to evaluate (1) trends in HLHS surgical outcomes including in-hospital mortality, length of stay (LOS), and cost, and (2) patient and hospital risk factors associated with these outcomes. Hospitalizations for patients with HLHS, including stage I, II, and III palliations, were analyzed using the Kids' Inpatient Database from 2000 through 2009. Trends in mortality, LOS, and cost were analyzed and chi-squared tests were used to test association between categorical variables. Patient and hospital characteristics associated with death were analyzed using logistic regression and associations with LOS were analyzed using ordinary least squared regression. There were 16,923 hospital admissions in patients with HLHS of which 5,672 (34%) included surgical intervention. Total (3,201-5,102) and surgery-specific admissions (1,165-1,618) increased from 2000 to 2009. Mortality decreased 14% per year in stage III palliations (odds ratio [OR] 0.86; 95% confidence interval [CI]: 0.79-0.94) and 6% per year for stage I palliations (OR 0.94; 95% CI 0.90-0.99) but not for stage II palliations (OR 1.01; 95% CI; 0.89-1.14). Length of stay increased for stage I and II palliations; however, per-patient hospital cost decreased in 2009. In conclusion, recent decrease in per patient cost for staged surgical palliation for HLHS has correlated temporally with improved mortality.

Outcomes of infants weighing three kilograms or less requiring extracorporeal membrane oxygenation after cardiac surgery

BACKGROUND

Extracorporeal membrane oxygenation (ECMO) is the most common form of cardiac support for postcardiotomy cardiac failure in children. While its benefits have been thoroughly explored in infants weighing more than 3 kg, similar analyses are lacking in lower weight neonates. This single-center study investigated outcomes and risks for poor survival among infants weighing 3 kg or less.

METHODS

A retrospective review of infants 3 kg or less who required postcardiotomy ECMO support was performed (January 1, 1999 to December 31, 2010). Primary outcome was 30-day survival after decannulation. Factors analyzed for association with poor outcome included demographics, cardiac anatomy, bypass and circulatory arrest times, total ECMO support time, postoperative lactate, inotrope use, and need for renal replacement therapy.

RESULTS

During the study period, 64 patients weighing 3 kg or less required postcardiotomy ECMO. Median gestational age and age at ECMO initiation were 38 weeks (interquartile range, 36 to 39) and 7 days (interquartile range, 4 to 9), respectively, with median ECMO support time of 164 hours (interquartile range, 95 to 231). Overall 30-day survival after decannulation was 33%. Factors associated with poor outcome were longer duration of support (231 hours or more, 12% survival, versus less than 231 hours, 40% survival; p = 0.05) and renal replacement therapy (n = 36, survival 17% versus 54%; p = 0.002). Multivariable regression analysis identified renal replacement therapy as the only independent factor associated with poor survival (odds ratio 4.3, 95% confidence interval: 1.3 to 14.9, p = 0.02).

CONCLUSIONS

For infants weighing 3 kg or less, 30-day survival after decannulation after cardiac ECMO is poor. Factors associated with poor prognosis were need for renal replacement therapy and longer duration of ECMO support. These findings may provide a useful guide for medical decision making among this unique, high-risk patient group.