Genetic and clinical variables act synergistically to impact neurodevelopmental outcomes in children with single ventricle heart disease.

BACKGROUND: Recent large-scale sequencing efforts have shed light on the genetic contribution to the etiology of congenital heart defects (CHD); however, the relative impact of genetics on clinical outcomes remains less understood. Outcomes analyses using genetics are complicated by the intrinsic severity of the CHD lesion and interactions with conditionally dependent clinical variables. METHODS: Bayesian Networks were applied to describe the intertwined relationships between clinical variables, demography, and genetics in a cohort of children with single ventricle CHD. RESULTS: As isolated variables, a damaging genetic variant in a gene related to abnormal heart morphology and prolonged ventilator support following stage I palliative surgery increase the probability of having a low Mental Developmental Index (MDI) score at 14 months of age by 1.9- and 5.8-fold, respectively. However, in combination, these variables act synergistically to further increase the probability of a low MDI score by 10-fold. The absence of a damaging variant in a known syndromic CHD gene and a shorter post-operative ventilator support increase the probability of a normal MDI score 1.7- and 2.4-fold, respectively, but in combination increase the probability of a good outcome by 59-fold. CONCLUSIONS: Our analyses suggest a modest genetic contribution to neurodevelopmental outcomes as isolated variables, similar to known clinical predictors. By contrast, genetic, demographic, and clinical variables interact synergistically to markedly impact clinical outcomes. These findings underscore the importance of capturing and quantifying the impact of damaging genomic variants in the context of multiple, conditionally dependent variables, such as pre- and post-operative factors, and demography.

Single ventricle congenital heart disease is a birth defect. In these children, the heart has only one effective blood-pumping chamber instead of two. Surgery can reroute the blood to use only one chamber, but multiple risk factors influence how well a child develops afterwards. Studying these risk factors can be challenging because they are interconnected, i.e. children with a genetic birth defect may be more likely to have a lower birthweight, and hence more likely to spend longer in hospital after surgery. Here, we used a statistical approach not commonly applied to study congenital heart disease and describe that whether a genetic variant (a small difference in a child's DNA) is important for how a child with single ventricle heart disease develops and grows after surgery depends on the presence of other risk factors.

Impact of Ventricular Dysfunction and Atrioventricular Valve Regurgitation on Pre-Fontan Attrition.

BACKGROUND: There is a significant incidence of pre-Fontan attrition-defined as failure to undergo Fontan completion-after superior cavopulmonary connection. This study investigated the impact of at least moderate ventricular dysfunction (VD) and atrioventricular valve regurgitation (AVVR) on pre-Fontan attrition. METHODS: This single-center retrospective cohort study included all infants who underwent Norwood palliation from 2008 to 2020 and subsequently underwent superior cavopulmonary connection. Pre-Fontan attrition was defined as death, listing for heart transplantation before Fontan completion, or unsuitability for Fontan completion. The study's secondary outcome was transplant-free survival. RESULTS: Pre-Fontan attrition occurred in 34 of 267 patients (12.7%). Isolated VD was not associated with attrition. However, patients with isolated AVVR had 5 times the odds of attrition (odds ratio, 5.4; 95% CI 1.8-16.2), and patients with both VD and AVVR had 20 times the odds of attrition (odds ratio, 20.1; 95% CI 7.7-52.8) compared with patients without VD or AVVR. Only patients with both VD and AVVR had significantly worse transplant-free survival compared with patients without VD or AVVR (hazard ratio, 7.7; 95% CI 2.8-21.6). CONCLUSIONS: The additive effect of VD and AVVR is a powerful contributor to pre-Fontan attrition. Future research investigating therapies that can mitigate the degree of AVVR may help improve Fontan completion rates and long-term outcomes.

Occlusion Pressure of the Thoracic Duct in Fontan Patients With Lymphatic Failure: Does Dilatation Challenge Contractility?

BACKGROUND: The Fontan circulation challenges the lymphatic system. Increasing production of lymphatic fluid and impeding lymphatic return, increased venous pressure may cause lymphatic dilatation and decrease lymphatic contractility. In-vitro studies have reported a lymphatic diameter-tension curve, with increasing passive stretch affecting the intrinsic contractile properties of each thoracic duct segment. We aimed to describe thoracic duct occlusion pressure and asses if thoracic duct dilation impairs contractility in individuals with a Fontan circulation and lymphatic failure. METHODS: Central venous pressure and thoracic duct measurements were retrospectively collected from 31 individuals with a Fontan circulation. Thoracic duct occlusion pressure was assessed during a period of external manual compression and used as an indicator of lymphatic vessel contractility. Measurements of pressure were correlated with measurements of the thoracic duct diameter in images obtained by dynamic contrast-enhanced MR lymphangiography. RESULTS: The average central venous pressure and average pressure of the thoracic duct were 17 mm Hg. During manual occlusion, the thoracic duct pressure significantly increased to 32 mm Hg. The average thoracic duct diameter was 3.3 mm. Thoracic duct diameter correlated closely with the central venous pressure. The rise in pressure following manual occlusion showed an inverse correlation with the diameter of the thoracic duct. CONCLUSION: Higher central venous pressures are associated with increasing diameters of the thoracic duct. When challenged by manual occlusion, dilated thoracic ducts display a decreased ability to increase pressure. Dilatation and a resulting decreased contractility may partly explain the challenged lymphatic system in individuals with a Fontan circulation.

Feeding challenges in the newborn with congenital heart disease.

PURPOSE OF REVIEW: Feeding challenges and growth failure are lifelong issues for infants with congenital heart disease. The purpose of this review is to summarize the literature on the topic from North America. RECENT FINDINGS: Despite recognition of feeding challenges and ongoing national collaboration, >50% of infants with univentricular physiology continue to require supplemental tube feeds at the time of discharge from neonatal surgery. Preoperative feeding is now commonly used in prostaglandin dependent neonates with congenital heart disease. The value of a structured nutritional program with establishment of best practices in nutrition is well recognized in the current era. Despite implementation of these best practices, neonates undergoing cardiac surgery continue to struggle with weight gain prior to discharge. This suggests that there is more to growth than provision of adequate nutrition alone. SUMMARY: The National Pediatric Cardiology Quality Improvement Collaborative continues to play a major role in optimizing nutrition in infants with congenital heart disease. This among other registries underscores the importance of collaboration in improving overall outcomes for children with congenital heart disease. Nurses should be encouraged to lead both clinical and research efforts to overcome feeding challenges encountered by these children.

New insights on growth trajectory in infants with complex congenital heart disease.

PURPOSE: We aimed to describe the weight-for-age Z-score growth trajectory (WAZ-GT) of infants with complex congenital heart disease (cCHD) after neonatal cardiac surgery in the first 4 months of life and assess potential risk factors. METHODS: We utilized data from a previously reported trial of the REACH telehealth home monitoring (NCT01941667) program which evaluated 178 infants with cCHD from 2012 to 2017. Over the first 4 months of life, weekly infant weights were converted to WAZ. WAZ-GT classes were identified using latent class growth modeling. Multinomial logistic regression models were used to examine the associations between potential risk factors and WAZ-GT classes. RESULTS: Four distinct classes of WAZ-GT were identified: maintaining WAZ > 0, 14%; stable around WAZ = 0, 35%; partially recovered, 28%; never recovered, 23%. Compared with reference group "stable around WAZ=0," we identified clinical and sociodemographic determinants of class membership for the three remaining groups. "Maintaining WAZ > 0" had greater odds of having biventricular physiology, borderline appetite, and a parent with at least a college education. "Partially recovered" had greater odds of hospital length of stay>14 days and being a single child in the household. "Never recovered" had greater odds hospital length of stay >14 and > 30 days, tube feeding at discharge, and low appetite. CONCLUSIONS: This study described distinct classes of WAZ-GT for infants with cCHD early in infancy and identified associated determinants. PRACTICE IMPLICATIONS: Findings from this study can be used in the identification of infants at risk of poor WAZ-GT and in the design of interventions to target growth in this vulnerable patient population.

Post-operative Chylothorax in Patients with Repaired Transposition of the Great Arteries.

Patients with dextro-transposition of the great arteries (d-TGA) require surgical repair as neonates. These patients are at risk for post-operative chylothorax. We sought to describe the presentation, imaging, and outcomes after intervention for patients with d-TGA with post-operative chylothorax. A retrospective chart review was performed in patients with repaired d-TGA who were referred from 1/1/2013 to 4/1/2020 for evaluation of chylothorax. Patient history, lymphatic imaging, and interventional data were collected. Impact of intervention on lymphatic drainage was evaluated with a student's t-test. Eight patients met inclusion criteria for this study. Five patients had a history of central venous thrombus leading to thoracic duct outlet occlusion. Five patients underwent intervention, two were managed conservatively, and one was not a candidate for intervention. Chylothorax resolved in six patients. There was a significant difference in output from 7 days prior to first intervention (114 mL/kg/day) compared to 28 days following final intervention (27 mL/kg/day, p = 0.034). There were no procedural complications. Chylothorax in patients with repaired transposition of the great arteries is often amenable to intervention. Early surveillance and management of central venous thrombosis may reduce the burden of lymphatic disease in these patients.

Identifying Risk Factors for Complicated Post-operative Course in Tetralogy of Fallot Using a Machine Learning Approach.

Introduction: Tetralogy of Fallot (TOF) repair is associated with excellent operative survival. However, a subset of patients experiences post-operative complications, which can significantly alter the early and late post-operative course. We utilized a machine learning approach to identify risk factors for post-operative complications after TOF repair. Methods: We conducted a single-center prospective cohort study of children <2 years of age with TOF undergoing surgical repair. The outcome was occurrence of post-operative cardiac complications, measured between TOF repair and hospital discharge or death. Predictors included patient, operative, and echocardiographic variables, including pre-operative right ventricular strain and fractional area change as measures of right ventricular function. Gradient-boosted quantile regression models (GBM) determined predictors of post-operative complications. Cross-validated GBMs were implemented with and without a filtering stage non-parametric regression model to select a subset of clinically meaningful predictors. Sensitivity analysis with gradient-boosted Poisson regression models was used to examine if the same predictors were identified in the subset of patients with at least one complication. Results: Of the 162 subjects enrolled between March 2012 and May 2018, 43 (26.5%) had at least one post-operative cardiac complication. The most frequent complications were arrhythmia requiring treatment (N = 22, 13.6%), cardiac catheterization (N = 17, 10.5%), and extracorporeal membrane oxygenation (ECMO) (N = 11, 6.8%). Fifty-six variables were used in the machine learning analysis, of which there were 21 predictors that were already identified from the first-stage regression. Duration of cardiopulmonary bypass (CPB) was the highest ranked predictor in all models. Other predictors included gestational age, pre-operative right ventricular (RV) global longitudinal strain, pulmonary valve Z-score, and immediate post-operative arterial oxygen level. Sensitivity analysis identified similar predictors, confirming the robustness of these findings across models. Conclusions: Cardiac complications after TOF repair are prevalent in a quarter of patients. A prolonged surgery remains an important predictor of post-operative complications; however, other perioperative factors are likewise important, including pre-operative right ventricular remodeling. This study identifies potential opportunities to optimize the surgical repair for TOF to diminish post-operative complications and secure improved clinical outcomes. Efforts toward optimizing pre-operative ventricular remodeling might mitigate post-operative complications and help reduce future morbidity.

Attrition between the superior cavopulmonary connection and the Fontan procedure in hypoplastic left heart syndrome.

OBJECTIVE: We investigated the incidence and predictors of failure to undergo the Fontan in children with hypoplastic left heart syndrome who survived superior cavopulmonary connection. METHODS: The cohort consists of all patients with hypoplastic left heart syndrome who survived to hospital discharge after superior cavopulmonary connection between 1988 and 2017. The primary outcome was attrition, which was defined as death, nonsuitability for the Fontan, or cardiac transplantation before the Fontan. Subjects were excluded if they were awaiting the Fontan, were lost to follow-up, or underwent biventricular repair. The study period was divided into 4 eras based on changes in operative or medical management. Attrition was estimated with 95% confidence intervals, and predictors were identified using adjusted, logistic regression models. RESULTS: Of the 856 hospital survivors after superior cavopulmonary connection, 52 died, 7 were deemed unsuitable for Fontan, and 12 underwent or were awaiting heart transplant. Overall attrition was 8.3% (71/856). Attrition rate did not change significantly across eras. A best-fitting multiple logistic regression model was used, adjusting for superior cavopulmonary connection year and other influential covariates: right ventricle to pulmonary artery shunt at Norwood (P < .01), total support time at superior cavopulmonary connection (P < .01), atrioventricular valve reconstruction at superior cavopulmonary connection (P = .02), performance of other procedures at superior cavopulmonary connection (P = .01), and length of stay after superior cavopulmonary connection (P < .01). CONCLUSIONS: In this study spanning more than 3 decades, 8.3% of children with hypoplastic left heart syndrome failed to undergo the Fontan after superior cavopulmonary connection. This attrition rate has not decreased over 30 years. Use of a right ventricle to pulmonary artery shunt at the Norwood procedure was associated with increased attrition.

Standardized Feeding Approach Mitigates Weight Loss in Infants with Congenital Heart Disease.

OBJECTIVE: To evaluate the effect of a standardized feeding approach using a clinical nutrition pathway on weight-for-age Z score (WAZ) over hospital length of stay (HLOS) for infants with congenital heart disease (CHD). STUDY DESIGN: A 10-year retrospective cohort study examined eligible infants who underwent neonatal cardiac surgery between July 2009 and December 2018 (n = 987). Eligibility criteria included infants born at least 37 weeks of gestation and a minimum birth weight of 2 kg who underwent cardiac surgery for CHD within the first 30 days of life. Using the best linear unbiased predictions from a linear mixed effects model, WAZ change over HLOS was estimated before and after January 2013, when the standardized feeding approach was initiated. The best linear unbiased predictions model included adjustment for patient characteristics including sex, race, HLOS, and class of cardiac defect. RESULTS: The change in WAZ over HLOS was significantly higher from 2013 to 2018 than from 2009 to 2012 (ß = 0.16; SE = 0.02; P < .001), after controlling for sex, race, HLOS, and CHD category, indicating that infants experienced a decreased WAZ loss over HLOS after the standardized feeding approach was initiated. Additionally, differences were found in WAZ loss over HLOS between infants with single ventricle CHD (ß = 0.26; SE = 0.04; P < .001) and 2 ventricle CHD (ß = 0.04; SE = 0.02; P = .04). CONCLUSIONS: These data suggest that an organized, focused approach for nutrition therapy using a standardized pathway improves weight change outcomes before hospital discharge for infants with single and 2 ventricle CHD who require neonatal cardiac surgery.

Decreasing Interstage Mortality After the Norwood Procedure: A 30-Year Experience.

Background The superior cavo-pulmonary connection was introduced at our institution in 1988 for infants undergoing surgery for hypoplastic left heart syndrome. Patients with hypoplastic left heart syndrome remain at high risk for mortality in the time period between the Norwood procedure and the superior cavo-pulmonary connection. The primary objectives of this study were to compare interstage mortality across 4 eras and analyze factors that may impact interstage mortality. Methods and Results Patients with hypoplastic left heart syndrome who underwent the Norwood procedure, were discharged from the hospital, and were eligible for superior cavo-pulmonary connection between January 1, 1988, and December 31, 2017, were included. The study period was divided into 4 eras based on changes in operative or medical management. Mortality rates were estimated with 95% CIs. Adjusted and unadjusted logistic regression models were used to identify risk factors for mortality. There were 1111 patients who met the inclusion criteria. Overall, interstage mortality was 120/1111 (10.8%). Interstage mortality was significantly lower in era 4 relative to era 1 (4.6% versus 13.4%; P=0.02) during the time that age at the superior cavo-pulmonary connection was the lowest (135 days; P<0.01) and the interstage monitoring program was introduced. In addition, use of the right ventricle to pulmonary artery shunt was associated with decreased interstage mortality (P=0.02) and was more routinely practiced in era 4. Conclusions During this 30-year experience, the risk of interstage mortality decreased significantly in the most recent era. Factors that coincide with this finding include younger age at superior cavo-pulmonary connection, introduction of an interstage monitoring program, and increased use of the right ventricle to pulmonary artery shunt.

Telehealth Home Monitoring and Postcardiac Surgery for Congenital Heart Disease.

OBJECTIVES: To test the effect of a 4-month telehealth home monitoring program (REACH), layered on usual care, on postdischarge outcomes in parents of infants recovering from cardiac surgery and their infants. METHODS: Randomized trial of infants discharged from the hospital after cardiac surgery for congenital heart disease. Consecutive infants with complex congenital heart disease undergoing cardiac surgery within 21 days of life were enrolled at 3 university-affiliated pediatric cardiac centers. RESULTS: From 2012 to 2016, 219 parent-infant dyads were enrolled; 109 were randomly assigned to the intervention group and 110 to the control group. At 4 months postdischarge, parenting stress was not significantly different between groups (total Parenting Stress Index in the intervention group was 220 and in the control group was 215; P = .61). The percentages of parents who met posttraumatic stress disorder (PTSD) criteria and parent quality of life inventory scores were also not significantly different between the 2 groups (PTSD in the intervention group was 18% and was 18% in the control group; P =.56; the mean Ulm Quality of Life Inventory for Parents in the intervention group was 71 andwas 70 in the control group; P = .88). Infant growth in both groups was suboptimal (the mean weight-for-age z scores were -1.1 in the intervention group and -1.2 in the control group; P = .56), and more infants in the intervention group were readmitted to the hospital (66% in the intervention group versus 57% in the control group; P < .001). CONCLUSIONS: When added to usual care, the REACH intervention was not associated with an improvement in parent or infant outcomes. Four months after neonatal heart surgery, ∼20% of parents demonstrate PTSD symptoms. Suboptimal infant growth and hospital readmissions were common.

Standardization of the Perioperative Management for Neonates Undergoing the Norwood Operation for Hypoplastic Left Heart Syndrome and Related Heart Defects.

OBJECTIVES: In-hospital complications after the Norwood operation for single ventricle heart defects account for the majority of morbidity and mortality. Inpatient care variation occurs within and across centers. This multidisciplinary quality improvement project standardized perioperative management in a large referral center. DESIGN: Quality improvement project. SETTING: High volume cardiac center, tertiary care children's hospital. PATIENTS: Neonates undergoing Norwood operation. INTERVENTIONS: The quality improvement team developed and implemented a clinical guideline (preoperative admission to 48 hr after surgery). The composite process metric, Guideline Adherence Score, contained 13 recommendations in the guideline that reflected consistent care for all patients. MEASUREMENTS AND MAIN RESULTS: One-hundred two consecutive neonates who underwent Norwood operation (January 1, 2013, to July 12, 2016) before guideline implementation were compared with 50 consecutive neonates after guideline implementation (July 13, 2016, to May 4, 2018). No preguideline operations met the goal Guideline Adherence Score. In the first 6 months after guideline implementation, 10 of 12 operations achieved goal Guideline Adherence Score and continued through implementation, reaching 100% for the last 10 operations. Statistical process control analysis demonstrated less variability and decreased hours of postoperative mechanical ventilation and cardiac ICU length of stay during implementation. There were no statistically significant differences in major hospital complications or in 30-day mortality. A higher percentage of patients were extubated by postoperative day 2 after guideline implementation (67% [30/47] vs 41% [41/99], respectively; p = 0.01). Of these patients, reintubation within 72 hours of extubation significantly decreased after guideline implementation (0% [0/30] vs 17% [7/41] patients, respectively; p = 0.02). CONCLUSIONS: This initiative successfully implemented a standardized perioperative care guideline for neonates undergoing the Norwood operation at a large center. Positive statistical process control centerline shifts in Guideline Adherence Score, length of postoperative mechanical ventilation, and cardiac ICU length of stay were demonstrated. A higher percentage were successfully extubated by postoperative day 2. Establishment of standard processes can lead to best practices to decrease major adverse events.

Outcomes for the superior cavopulmonary connection in children with hypoplastic left heart syndrome: a 30-year experience.

OBJECTIVES: The objective of this study was to estimate hospital mortality and length of stay (LOS) for children with hypoplastic left heart syndrome undergoing superior cavopulmonary connection (SCPC). METHODS: All hypoplastic left heart syndrome interstage survivors who underwent SCPC between 1 January 1988 and 31 December 2017 were included. The study period was divided into 4 eras based on changes in operative or medical management. Mortality rates were estimated using standard binomial proportions. Adjusted and unadjusted logistic regression models were used to identify risk factors for mortality and LOS. RESULTS: The most common procedures for the cohort (n = 958) were Hemi-Fontan (57.3%) or Bidrectional Glenn shunt (35.7%). The mortality was 4.1% overall and decreased in all 3 later eras compared to era 1. Factors associated with mortality in a multiple covariate model included longer total support time, earlier gestational age, longer LOS at the Norwood Procedure and need for additional procedures. Overall, the median LOS was 7.0 days with a decrease from eras 1 to 2 and plateaued in eras 3 and 4. Predictors of longer LOS included genetic anomaly, longer Norwood LOS, additional procedures, lower weight at surgery and longer total support time. The type of SCPC was not associated with mortality or LOS. CONCLUSIONS: In this large cohort of patients with hypoplastic left heart syndrome undergoing SCPC, hospital mortality has decreased significantly. LOS initially declined but plateaued in recent eras. The risk factors for mortality and longer LOS are related to patient and procedural complexity, especially the need for additional procedures at the time of SCPC.

Prevalence and Cause of Early Fontan Complications: Does the Lymphatic Circulation Play a Role?

Background Recent studies suggest that lymphatic congestion plays a role in development of late Fontan complications, such as protein-losing enteropathy. However, the role of the lymphatic circulation in early post-Fontan outcomes is not well defined. Methods and Results This was a retrospective, single-center study of patients undergoing first-time Fontan completion from 2012 to 2017. The primary outcome was early Fontan complication ≤6 months after surgery, a composite of death, Fontan takedown, extracorporeal membrane oxygenation, chest tube drainage >14 days, cardiac catheterization, readmission, or transplant. Complication causes were assigned to 1 of 4 groups: (1) Fontan circuit obstruction, (2) ventricular dysfunction or atrioventricular valve regurgitation, (3) persistent pleural effusions in the absence of Fontan obstruction or ventricular dysfunction, and (4) chylothorax or plastic bronchitis. T2-weighted magnetic resonance imaging sequences were used to assess for lymphatic perfusion abnormality. The cohort consisted of 238 patients. Fifty-eight (24%) developed early complications: 20 of 58 (34.5%) in group 1, 8 of 58 (14%) in group 2, 18 of 58 (31%) in group 3, and 12 of 58 (20%) in group 4. Preoperative T2 imaging was available for 126 (53%) patients. Patients with high-grade lymphatic abnormalities had 6 times greater odds of developing early complications (P=0.001). Conclusions There is substantial morbidity in the early post-Fontan period. Half of those who developed early complications had lymphatic failure or persistent effusions unrelated to structural or functional abnormalities. Preoperative T2 imaging demonstrated that patients with higher-grade lymphatic perfusion abnormalities were significantly more likely to develop early complications. This has implications for risk stratification and optimization of patients before Fontan palliation.

Protein Losing Enteropathy After Fontan Operation: Glimpses of Clarity Through the Lifting Fog.

Fontan-associated protein losing enteropathy is a challenge to treat and is a major contributor to morbidity and mortality in patients with palliated single ventricle. Numerous strategies for management have been proposed, with confusion as to how best to stratify and implement care among the many treatments available. Medical management can be helpful in some, while novel lymphatic interventions hold potential for remission with good results. We review our institutional approach to protein losing enteropathy after Fontan operation and provide a suggested algorithm and pathway for effective care.

Evaluating the utility of routine screening catheterisation before interstage discharge of infants with single-ventricle physiology.

INTRODUCTION: Interstage mortality causes are often unknown in infants with shunt-dependent univentricular defects. For 2 years, screening catheterisation was encouraged before neonatal discharge to determine if routine evaluation improved interstage outcomes. METHODS: Retrospective single-centre review of home monitoring programme from December, 2010 to June, 2012. Composite scores were created for physical examination/echocardiography risk factors; catheterisation risk factors; and interstage adverse events. Composite scores were compared between usual care and screening catheterisation groups. The ability of each risk factor composite to predict interstage adverse events, individually and in combination, was assessed with sensitivity, specificity, and receiver operating characteristic curves. RESULTS: There were 27 usual care and 32 screening catheterisation patients. There were no significant differences between groups except rates of catheterisation before discharge (29.6 versus 100%, p < 0.001). Usual care patients who underwent catheterisation for clinical indications had higher intervention rates (37.5 versus 3.1%, p = 0.004). Physical examination/echocardiography risk factor frequency was similar, but usual care patients with catheterisation had a higher catheterisation risk factor frequency. Interstage adverse event frequency was similar (48.2 versus 53.1%, p = 0.7). For interstage adverse event prediction, sensitivity for the physical examination/echocardiography, catheterisation, and either risk factor composites was 53.3, 72, and 80%, respectively; specificity was 59, 60, and 48%. The area under the receiver operating characteristic curve was 0.56, 0.66, and 0.64. CONCLUSION: Screening catheterisation evaluation offered slightly increased sensitivity and specificity, but no difference in interstage adverse event frequency. Given this small advantage versus known risks, screening catheterisations are no longer encouraged.

Association of a Home Monitoring Program With Interstage and Stage 2 Outcomes.

Background In shunt-dependent, single-ventricle patients, mortality remains high in the interstage period between discharge after neonatal surgery and stage 2 operation. We sought to evaluate the impact of our infant single-ventricle management and monitoring program ( ISVMP ) on interstage mortality and stage 2 outcomes. Methods and Results This retrospective single-center cohort study compared patients enrolled in ISVMP at hospital discharge with historical controls. The relationship of ISVMP to interstage mortality was determined with a bivariate probit model for the joint modeling of both groups, using an instrumental variables approach. We included 166 ISVMP participants (December 1, 2010, to June 30, 2015) and 168 controls (January 1, 2007, to November 30, 2010). The groups did not differ by anatomy, gender, race, or genetic syndrome. Mortality was lower in the ISVMP group (5.4%) versus controls (13%). An ISVMP infant compared with a historical control had an average 29% lower predicted probability of interstage death (adjusted probability: -0.29; 95% CI , -0.52 to -0.057; P=0.015). On stratified analysis, mortality was lower in the hypoplastic left heart syndrome subgroup undergoing Norwood operation (4/84 [4.8%] versus 12/90 [14%], P=0.03) but not in those with initial palliation of shunt only ( P=0.90). ISVMP participants were younger at the time of the stage 2 operation (138 versus 160 days, P<0.001), with no difference in postoperative mortality or length of stay. Conclusions In this single-center study, we report significantly lower interstage mortality for participants with hypoplastic left heart syndrome enrolled in ISVMP . Younger age at stage 2 operation was not associated with postoperative mortality or longer length of stay.

Longitudinal growth in patients with single ventricle cardiac disease receiving tube-assisted feeds.

OBJECTIVE: Children with single ventricle cardiac disease (SVCD) have poor growth in early life. Tube-assisted feeding (TF) is used to improve weight gain, but its impact on long-term growth remains unknown. We sought to compare the longitudinal growth of SVCD patients receiving TF after initial cardiac surgery with those fed entirely by mouth. DESIGN: We conducted a retrospective cohort study of SVCD patients who underwent initial surgical palliation between 1999 and 2009. We defined TF as the use of nasogastric, gastrostomy, or jejunostomy TF. We compared maximal attained growth z-scores for each year of life between TF and non-TF patients. A secondary analysis compared surgical and clinical factors between groups. RESULTS: A total of 134 patients were included; 64% were male and 68% underwent the Norwood operation. One third of patients (44) received TF. Adjusting for age, TF patients had an average of 0.56 lower weight-for-age z-score (WAZ) than non-TF patients (P = 0.007) through the age of 6 years. Longitudinal height was not affected by TF status (P = 0.15). In a subanalysis of Norwood patients, TF patients had lower WAZ at initial hospital discharge despite longer LOS. TF patients had diminished WAZ after adjusting for complications, interstage hospitalizations, and timing of subsequent operations. CONCLUSIONS: In this single-center study, patients with SVCD requiring TF at discharge from initial surgical palliation had diminished WAZ at discharge and on long-term follow-up, despite controlling for other identifiable risk factors. Further investigation is needed to understand the mechanisms underlying this phenomenon and to risk stratify infants who go home on TF.

Risk factors for mortality in paediatric cardiac ICU patients managed with extracorporeal membrane oxygenation.

BACKGROUND: Veno-arterial extracorporeal membrane oxygenation is frequently used in patients with cardiac disease. We evaluated short-term outcomes and identified factors associated with hospital mortality in cardiac patients supported with veno-arterial extracorporeal membrane oxygenation. METHODS: A retrospective review of patients supported with veno-arterial extracorporeal membrane oxygenation at a university-affiliated children's hospital was performed. RESULTS: A total of 253 patients with cardiac disease managed with extracorporeal membrane oxygenation were identified; survival to discharge was 48%, which significantly improved from 39% in an earlier era (1995-2001) (p=0.01). Patients were categorised into surgical versus non-surgical groups on the basis of whether they had undergone cardiac surgery before or not, respectively. The most common indication for extracorporeal membrane oxygenation was extracorporeal cardiopulmonary resuscitation: 96 (51%) in the surgical group and 45 (68%) in the non-surgical group. In a multiple covariate analysis, single-ventricle physiology (p=0.01), duration of extracorporeal membrane oxygenation (p<0.01), and length of hospital stay (p=0.03) were associated with hospital mortality. Weekend or night shift cannulation was associated with mortality in non-surgical patients (p=0.05). CONCLUSION: We report improvement in survival compared with an earlier era in cardiac patients supported with extracorporeal membrane oxygenation. Single-ventricle physiology continues to negatively impact survival, along with evidence of organ dysfunction during extracorporeal membrane oxygenation, duration of extracorporeal membrane oxygenation, and length of stay.

Variation in care for infants undergoing the Stage II palliation for hypoplastic left heart syndrome.

BACKGROUND: The Single Ventricle Reconstruction trial randomised neonates with hypoplastic left heart syndrome to a systemic-to-pulmonary-artery shunt strategy. Patients received care according to usual institutional practice. We analysed practice variation at the Stage II surgery to attempt to identify areas for decreased variation and process control improvement. METHODS: Prospectively collected data were available in the Single Ventricle Reconstruction public-use database. Practice variation across 14 centres was described for 397 patients who underwent Stage II surgery. Data are centre-level specific and reported as interquartile ranges across all centres, unless otherwise specified. RESULTS: Preoperative Stage II median age and weight across centres were 5.4 months (interquartile range 4.9-5.7) and 5.7 kg (5.5-6.1), with 70% performed electively. Most patients had pre-Stage-II cardiac catheterisation (98.5-100%). Digoxin was used by 11/14 centres in 25% of patients (23-31%), and 81% had some oral feeds (68-84%). The majority of the centres (86%) performed a bidirectional Glenn versus hemi-Fontan. Median cardiopulmonary bypass time was 96 minutes (75-113). In aggregate, 26% of patients had deep hypothermic circulatory arrest >10 minutes. In 13/14 centres using deep hypothermic circulatory arrest, 12.5% of patients exceeded 10 minutes (8-32%). Seven centres extubated 5% of patients (2-40) in the operating room. Postoperatively, ICU length of stay was 4.8 days (4.0-5.3) and total length of stay was 7.5 days (6-10). CONCLUSIONS: In the Single Ventricle Reconstruction Trial, practice varied widely among centres for nearly all perioperative factors surrounding Stage II. Further analysis may facilitate establishing best practices by identifying the impact of practice variation.