Optimal shunt type for Norwood procedure: Predicted adverse impact of discordant surgical approach.

BACKGROUND: The Single Ventricle Reconstruction (SVR) trial compared survival after Norwood procedure with either modified Blalock Taussig shunt (MBTS) or right ventricle pulmonary artery shunt (RVPAS). METHODS: Data from all 549 participants in the SVR trial were used to develop the MBTS TFSA algorithms, which predicted the transplantation free survival advantage (TFSA) following MBTS versus RVPAS at 1 and 6 years after Norwood procedure. Linear regression analysis of the MBTS TFSA values was performed to identify factors related to more optimal outcomes with MBTS at each timepoint. The impact of discordant management (ie. predicted shunt type did not equal the one actually received) on outcomes and the extent of inconsistencies between predictions were evaluated. RESULTS: The MBTS TFSA algorithm favored MBTS over RVPAS for only 6.2% of participants at 1 year and for 27.0% at 6 years. In terms of both 1- and 6-year outcomes, MBTS was favored with younger age at Norwood procedure and pre-Norwood intubation, while RVPAS was favored with younger gestational age and metrics indicating larger RV size in the parasternal echocardiographic views. Other predictors were timepoint specific. MBTS TFSA based allocation could have led to an absolute risk reduction in heart transplantation and mortality of 8.0% at 1 year and 16.8% at 6 years, mostly by preventing discordant MBTS management. Notably, separate predictions from the 1 year and 6-year algorithms produced discordant predictions for 136 participants (24.8%). CONCLUSIONS: The incorporation of data derived patient specific factors for selection of shunt type for the Norwood procedure may produce more optimal transplantation free survival. These precision medicine algorithms require prospective validation.

Multiple Biomarkers Are Equivalent to Clinical Pulmonary Arterial Hypertension Survival Risk Models.

BACKGROUND: Risk assessment in pulmonary arterial hypertension (PAH) is fundamental to guiding treatment and improved outcomes. Clinical models are excellent at identifying high-risk patients, but leave uncertainty amongst moderate-risk patients. RESEARCH QUESTION: Can a multiple blood biomarker model of PAH, using previously described biomarkers, improve risk discrimination over current models? STUDY DESIGN AND METHODS: Using a multiplex enzyme-linked immunosorbent assay, we measured N-terminal fragment of the prohormone brain natriuretic peptide (NT-proBNP), soluble suppressor of tumorigenicity, IL-6, endostatin, galectin 3, HDGF, and insulin-like growth factor binding proteins (IGFBP1-7) in training (n = 1,623), test (n = 696), and validation (n = 237) cohorts. Clinical variables and biomarkers were evaluated by principal component analysis. NT-proBNP was not included to develop a model independent of NT-proBNP. Unsupervised k-means clustering classified participants into clusters. Transplant-free survival by cluster was examined using Kaplan-Meier and Cox proportional hazard regressions. Hazard by cluster was compared with NT-proBNP, Registry to Evaluate Early and Long-Term PAH Disease Management (REVEAL), and European Society of Cardiology (ESC) and European Respiratory Society (ERS) risk models alone and combined clinical and biomarker models. RESULTS: The algorithm generated 5 clusters with good risk discrimination using 6 biomarkers, weight, height, and age at PAH diagnosis. In the test and validation cohorts, the biomarker model alone performed equivalent to REVEAL (area under the receiver operating characteristic curve, 0.74). Adding the biomarker model to the ESC and ERS score and REVEAL score improved the ESC and ERS score and REVEAL score. The best overall model was the biomarker model adjusted for NT-proBNP with the best C statistic, Akaike information criterion, and calibration for the adjusted model compared with either the biomarker or NT-proBNP model alone. INTERPRETATION: A multibiomarker model alone was equivalent to current PAH clinical mortality risk prediction models and improved performance when combined and added to NT-proBNP. Clinical risk scores offer excellent predictive models, but require multiple tests; adding blood biomarkers to models can improve prediction or can enable more frequent, noninvasive monitoring of risk in PAH to support therapeutic decision-making.

Factors Associated With Acute Kidney Injury After Cardiopulmonary Bypass in Children.

Background: Acute kidney injury (AKI) is a common complication after cardiovascular surgery in children, noted in approximately 40% of children undergoing cardiopulmonary bypass (CPB). We sought to determine the risk factors including inflammatory and vascular endothelial markers associated with AKI in children undergoing cardiac surgery. Methods: A secondary analysis of a prospective observational cohort study of paediatric patients with a cardiac defect requiring CPB and a weight of >2.5 kg was performed. AKI was defined as a 1.5 times increase from the preoperative value in serum creatinine or an absolute increase by ≥0.3 mg/dL (≥26.5 µmol/L). Plasma inflammatory markers (interleukin [IL]-1a, IL-1b, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12p70, and tumour necrosis factor α) and vascular endothelial markers (vascular endothelial growth factor, von Willebrand factor, regulated on activation, normal T-cell expressed and secreted, granulocyte macrophage colony-stimulating factor, monocyte chemoattractant protein-1, platelet-derived growth factor, and microparticles) were assessed at 5 perioperative time points. Associations with AKI were found using generalized linear regression models adjusted for repeated measures. Results: A total of 207 patients were assessed, of whom 56% (n = 116) were male. Thirty-three percent (n = 68) developed AKI. In univariable analyses, adverse outcomes significantly related to the presence of AKI included increased intensive care unit stay (3.0 vs 5.6 hours, P < 0.001). In multivariable analysis, independent factors that were significantly associated with AKI included longer duration of CPB (111 vs 154 minutes, P < 0.001) and lower preoperative creatinine. Inflammatory and vascular endothelial biomarkers were not associated with AKI. Conclusions: AKI remains a prevalent problem after cardiac surgery, and renal ischemia related to longer bypass time potentially plays a key role in the etiology. Inflammatory and vascular endothelial biomarkers were not significantly related to AKI.

Contexte: L'insuffisance rénale aiguë (IRA) est une complication fréquente qui survient chez les enfants après une intervention chirurgicale cardiovasculaire. Environ 40 % des enfants chez qui une circulation extracorporelle (CEC) est mise en place durant l'intervention présentent ultérieurement une IRA. Nous avons tenté de définir les facteurs de risque, y compris les marqueurs inflammatoires et endothéliaux vasculaires, qui sont associés à l'IRA chez les enfants qui subissent une intervention chirurgicale cardiaque. Méthodologie: Nous avons réalisé une analyse secondaire d'une étude de cohorte observationnelle prospective menée auprès d'enfants qui étaient atteints d'une anomalie cardiaque nécessitant une CEC et qui pesaient plus de 2,5 kg. L'IRA était définie comme une hausse du taux de créatinine sérique par un facteur de 1,5 par rapport à la valeur préopératoire ou comme une augmentation absolue de ≥ 0,3 mg/dL (≥ 26,5 µmol/l). Les marqueurs inflammatoires plasmatiques (interleukine [IL]-1a, IL-1b, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12p70, facteur de nécrose tumorale alpha) et les marqueurs endothéliaux vasculaires (facteur de croissance de l'endothélium vasculaire, facteur de von Willebrand, chimiokine exprimée et sécrétée après l'activation des lymphocytes T normaux, facteur de stimulation des granulocytes et macrophages, protéine chimiotactique des monocytes-1, facteur de croissance dérivé des plaquettes, microparticules) ont été évalués à 5 moments périopératoires différents. Les associations avec l'IRA ont été établies au moyen de modèles de régression linéaire généraux, qui ont été ajustés pour tenir compte des mesures répétées. Résultats: L'évaluation a porté sur 207 patients, dont 56 % (n = 116) étaient des garçons, et une IRA a été observée chez 33 % (n = 68) d'entre eux. Les résultats d'analyses univariées ont montré que les issues indésirables associées de façon significative à la présence d'une IRA comprenaient un séjour prolongé à l'unité de soins intensifs (3,0 c. 5,6 heures, p < 0,001). Dans les analyses multivariées, les facteurs indépendants associés de façon significative à une IRA comprenaient une CEC prolongée (111 c. 154 minutes, p < 0,001) et un faible taux de créatinine préopératoire. Les biomarqueurs inflammatoires et endothéliaux vasculaires n'ont pas été associés à l'IRA. Conclusions: L'IRA demeure un problème répandu après une intervention chirurgicale cardiaque. L'ischémie rénale associée à une CEC prolongée joue potentiellement un rôle clé dans son étiologie. Par ailleurs, les biomarqueurs inflammatoires et endothéliaux vasculaires n'ont pas été associés de façon significative à l'IRA.

The relationships between acetylcholine-induced chest pain, objective measures of coronary vascular function and symptom status.

Background: Acetylcholine-induced chest pain is routinely measured during the assessment of microvascular function. Aims: The aim was to determine the relationships between acetylcholine-induced chest pain and both symptom burden and objective measures of vascular function. Methods: In patients with angina but no obstructive coronary artery disease, invasive studies determined the presence or absence of chest pain during both acetylcholine and adenosine infusion. Thermodilution-derived coronary blood flow (CBF) and index of microvascular resistance (IMR) was determined at rest and during both acetylcholine and adenosine infusion. Patients with epicardial spasm (>90%) were excluded; vasoconstriction between 20% and 90% was considered endothelial dysfunction. Results: Eighty-seven patients met the inclusion criteria. Of these 52 patients (60%) experienced chest pain during acetylcholine while 35 (40%) did not. Those with acetylcholine-induced chest pain demonstrated: (1) Increased CBF at rest (1.6 ± 0.7 vs. 1.2 ± 0.4, p = 0.004) (2) Decreased IMR with acetylcholine (acetylcholine-IMR = 29.7 ± 16.3 vs. 40.4 ± 17.1, p = 0.004), (3) Equivalent IMR following adenosine (Adenosine-IMR: 21.1 ± 10.7 vs. 21.8 ± 8.2, p = 0.76), (4) Increased adenosine-induced chest pain (40/52 = 77% vs. 7/35 = 20%, p < 0.0001), (5) Increased chest pain during exercise testing (30/46 = 63% vs. 4/29 = 12%, p < 0.00001) with no differences in exercise duration or electrocardiographic changes, and (6) Increased prevalence of epicardial endothelial dysfunction (33/52 = 63% vs. 14/35 = 40%, p = 0.03). Conclusions: After excluding epicardial spasm, acetylcholine-induced chest pain is associated with increased pain during exercise and adenosine infusion, increased coronary blood flow at rest, decreased microvascular resistance in response to acetylcholine and increased prevalence of epicardial endothelial dysfunction. These findings raise questions about the mechanisms underlying acetylcholine-induced chest pain.

Association of Childhood Blood Pressure with Left Atrial Size and Function: Study of High Blood Pressure in Pediatrics-Adult Hypertension in Youth (SHIP AHOY).

OBJECTIVE(S): To evaluate the cross-sectional association of cardiovascular disease risk factors with left atrial (LA) size and function among healthy youth, aged 11-18 years, with a wide range of blood pressures (BPs). STUDY DESIGN: Echocardiographic images of youth enrolled in the Study of High Blood Pressure in Pediatrics: Adult Hypertension Onset in Youth study were analyzed for LA measurements. The association of casual BP, ambulatory BP, and other cardiovascular disease risk factors with LA size and function were determined using descriptive statistics and multivariable regression. Regression models adjusting for age, sex, race, and body mass index z score determined the independent association between ambulatory systolic BP indices (mean systolic BP/50th %ile systolic BP) and BP phenotypes with LA outcomes while exploratory analyses investigated for additional predictors of LA outcomes. RESULTS: The study population consisted of 347 youth: median age 15.7 years, 60% male and 40% non-White. Greater-risk casual systolic BP groups had worse cardiometabolic profiles but no differences in LA size and function. Each 0.1 increase in ambulatory systolic BP day or night index was associated with a 9.9 mL/m2 increase in LA volume/body surface area (LAV/BSA; 95th% CI 2.8-17.0, P = .006) and a 6.8 mL/m2 increase in LAV/BSA (95th% CI 0.8-12.8, P = .03), respectively. Ambulatory hypertension was associated with greater odds of abnormal LAV/BSA, defined as >75th %ile (2014 ambulatory BP monitoring criteria: OR 3.2 [95th% CI 1.4-7.2; P = .002]; 2022 ambulatory BP monitoring criteria: OR 2.1 [95th% CI 1.0-4.1; P = .008]). CONCLUSIONS: Increasing ambulatory systolic BP and ambulatory hypertension are independently associated with LAV/BSA.

Perioperative Metabolites Are Associated With Adverse Neonatal Congenital Heart Disease Surgical Outcomes.

Background Clinical risk factors in neonatal cardiac surgery do not fully capture discrepancies in outcomes. Targeted metabolomic analysis of plasma from neonates undergoing heart surgery with cardiopulmonary bypass was performed to determine associations with clinical outcomes. Methods and Result Samples and clinical variables from 149 neonates enrolled in the Corticosteroid Therapy in Neonates Undergoing Cardiopulmonary Bypass trial with surgical treatment for congenital heart disease between 2012 and 2016 were included. Blood samples were collected before skin incision, immediately after cardiopulmonary bypass, and 12 hours after surgery. Outcomes include composite morbidity/mortality (death, extracorporeal membrane oxygenation, cardiac arrest, acute kidney injury, and/or hepatic injury) and a cardiac composite (extracorporeal membrane oxygenation, cardiac arrest, or increase in lactate level), hepatic injury, and acute kidney injury. Targeted metabolite levels were determined by high-resolution tandem liquid chromatography and mass spectrometry. Principal component and regression analyses were used to assess associations between metabolic profiles and outcomes, with 2 models created: a base clinical model and a base model+metabolites. Of the 193 metabolites examined, 40 were detected and quantified. The first principal component, principal component 1, was composed mostly of preoperative metabolites and was significantly associated with the composite morbidity/mortality, cardiac composite, and hepatic injury outcomes. In regression models, individual metabolites also improved model performance for the composite morbidity/mortality, cardiac composite, and hepatic injury outcomes. Significant disease pathways included myocardial injury (false discovery rate, 0.00091) and heart failure (false discovery rate, 0.041). Conclusions In neonatal cardiac surgery, perioperative metabolites were associated with postoperative outcomes and improved clinical model outcome associations. Preoperative metabolite levels alone may improve risk models and provide a basis for optimizing perioperative care.

Prospective Assessment of Coronary Artery Flows Before and After Cardiopulmonary Bypass in Children With a Spectrum of Congenital Heart Disease.

Background: Normative data for the effect of cardiopulmonary bypass (CPB) on coronary artery Doppler velocities by transesophageal echocardiography in paediatric patients with congenital heart disease (CHD) are lacking. The objective of the study was to prospectively examine the effects of CPB on coronary artery flow patterns by transesophageal echocardiography before and after CPB in children with CHD. Methods: All cases undergoing CHD surgery at the Hospital for Sick Children, Toronto, were eligible. The excluded cases included Norwood operation, heart transplantation, or weight <2.5 kg. Coronary Dopplers and coronary flow reserve (CFR) for the right coronary artery (RCA) and left anterior descending (LAD) were obtained. Multivariable analyses using linear regression models were performed, adjusted for age and cross-clamp time. Results: From May 2017 to June 2018, 69 children (median age at surgery: 0.7 years, interquartile range [IQR]: 0.4-3.7 years; median weight: 7.4 kg, IQR: 5.8-13.3 kg) were included. They were grouped into shunt lesions (N = 26), obstructive lesions (N = 26), transposition of the great arteries (N = 5), and single ventricle (N = 12). N = 39 (57%) were primary repairs, and 56 (81%) had 1 CPB run. For RCA and LAD peak velocities, there was an increase from pre- to post-CPB in RCA peak 39 cm/s (IQR: 30-54 cm/s) to 65 cm/s (IQR: 47-81 cm/s), P < 0.001, mean CFR 1.52 (IQR: 1.25-1.81), and LAD peak 49 cm/s (IQR: 39-60 cm/s) to 70 cm/s (IQR: 52-90 cm/s), P < 0.001, mean CFR 1.48 (IQR: 1.14-1.77). Conclusions: Coronary flow velocities increase from pre- to post-CPB in congenital heart lesions. CFR is consistent across all lesions but is relatively low compared with the adult population.

Contexte: On ne dispose pas de données normatives sur les effets de la dérivation cardiopulmonaire (DCP) sur le débit coronarien mesuré au moyen d'une échocardiographie transœsophagienne Doppler chez des enfants présentant une cardiopathie congénitale. L'objectif de l'étude était d'examiner de manière prospective les effets de la DCP sur le débit coronarien avant et après l'intervention chez des enfants présentant une cardiopathie congénitale. Méthodologie: Tous les enfants ayant subi une intervention chirurgicale pour une cardiopathie congénitale à l'Hospital for Sick Children de Toronto étaient admissibles à l'étude, à l'exception de ceux ayant subi une intervention de Norwood ou une transplantation cardiaque, de même que les enfants pesant moins de 2,5 kg. Les résultats du test Doppler et la réserve coronarienne pour l'artère coronaire droite (ACD) et la branche antérieure de l'artère coronaire gauche (ACG) ont été obtenus. Des analyses multivariées ont été réalisées au moyen de modèles de régression linéaire, avec correction en fonction de l'âge et du temps de clampage total. Résultats: Entre mai 2017 et juin 2018, 69 enfants (âge médian au moment de la chirurgie : 0,7 an, intervalle interquartile (IIQ) : 0,4-3,7 ans; poids médian : 7,4 kg, IIQ : 5,8-13,3 kg) ont été inclus dans l'étude. Les sujets ont été répartis en quatre groupes : shunts (n = 26), lésions obstructives (n = 26), permutation des gros vaisseaux (n = 5) et ventricule unique (n = 12). Chez 39 sujets (57 %), il s'agissait d'une réparation primitive, et 56 enfants (81 %) avaient déjà subi une DCP. Les vitesses maximales dans l'ACD et dans la branche antérieure de l'ACG ont augmenté après la DCP, passant de 39 cm/s (IIQ : 30-54 cm/s) à 65 cm/s (IIQ : 47-81 cm/s), p < 0,001; réserve coronarienne moyenne : 1,52 (IIQ : 1,25-1,81) pour l'ACD, et de 49 cm/s (IIQ : 39-60 cm/s) à 70 cm/s (IIQ : 52-90 cm/s), p < 0,001; réserve coronarienne moyenne : 1,48 (IIQ : 1,14-1,77) pour la branche antérieure de l'ACG. Conclusions: Le débit coronarien augmente après une DCP dans les cas de lésions cardiaques congénitales. La réserve coronarienne est constante dans tous les types de lésions, mais elle est relativement faible comparativement à celle de la population adulte.

Neonatal encephalopathy plasma metabolites are associated with neurodevelopmental outcomes.

BACKGROUND: To investigate mechanisms of injury and recovery in neonatal encephalopathy (NE), we performed targeted metabolomic analysis of plasma using liquid chromatography with tandem mass spectrometry (LC/MS/MS) from healthy term neonates or neonates with NE. METHODS: Plasma samples from the NE (n = 45, day of life 0-1) or healthy neonatal (n = 30, ≥36 weeks gestation) cohorts had LC/MS/MS metabolomic profiling with a 193-plex targeted metabolite assay covering >366 metabolic pathways. Metabolite levels were compared to 2-year neurodevelopmental outcomes measured by the Bayley Scales of Infant and Toddler Development III (Bayley-III). RESULTS: Out of 193 metabolites, 57 met the pre-defined quality control criteria for analysis. Significant (after false discovery rate correction) KEGG (Kyoto Encyclopedia of Genes and Genomes) pathways included aminoacyl-tRNA biosynthesis, arginine biosynthesis, and metabolism of multiple amino acids. Significant disease pathways included seizures. In regression models, histidine and C6 sugar amine were significantly associated with cognitive, motor, and language and betaine with cognitive and motor Bayley-III composite scores. The addition of histidine, C6 sugar amine, and betaine to a Sarnat score-based clinical regression model significantly improved model performance (Akaike information criterion and adjusted r2) for Bayley-III cognitive, motor, and language scores. CONCLUSIONS: Plasma metabolites may help to predict neurological outcomes in neonatal brain injury and enhance current clinical predictors. IMPACT: Plasma metabolites may help to predict neurological outcomes in NE and supplement current clinical predictors. Current metabolomics research is limited in terms of clinical application and association with long-term outcomes. Our study presents novel associations of plasma metabolites from the first 24 h of life and 2-year neurodevelopmental outcomes for infants with NE. Our metabolomics discovery provides insight into possible disease mechanisms and methods to rescue and/or supplement metabolic pathways involved in NE. Our metabolomics discovery of metabolic pathway supplementations and/or rescue mechanisms may serve as adjunctive therapies for NE.

Metabolomic Profiling of Adults with Congenital Heart Disease.

Metabolomic analysis may provide an integrated assessment in genetically and pathologically heterogeneous populations. We used metabolomic analysis to gain mechanistic insight into the small and diverse population of adults with congenital heart disease (ACHD). Consecutive ACHD patients seen at a single institution were enrolled. Clinical variables and whole blood were collected at regular clinical visits. Stored plasma samples were analyzed for the concentrations of 674 metabolites and metabolic markers using mass spectrometry with internal standards. These samples were compared to 28 simultaneously assessed healthy non-ACHD controls. Principal component analysis and multivariable regression modeling were used to identify metabolites associated with clinical outcomes in ACHD. Plasma from ACHD and healthy control patients differed in the concentrations of multiple metabolites. Differences between control and ACHD were greater in number and in degree than those between ACHD anatomic groups. A metabolite cluster containing amino acids and metabolites of amino acids correlated with negative clinical outcomes across all anatomic groups. Metabolites in the arginine metabolic pathway, betaine, dehydroepiandrosterone, cystine, 1-methylhistidine, serotonin and bile acids were associated with specific clinical outcomes. Metabolic markers of disease may both be useful as biomarkers for disease activity and suggest etiologically related pathways as possible targets for disease-modifying intervention.

Association between genetic variants in the HIF1A-VEGF pathway and left ventricular regional myocardial deformation in patients with hypertrophic cardiomyopathy.

BACKGROUND: Information on genetic etiology of pediatric hypertrophic cardiomyopathy (HCM) rarely aids in risk stratification and prediction of disease onset. Little data exist on the association between genetic modifiers and phenotypic expression of myocardial performance, hampering an individual precision medicine approach. METHODS: Single-nucleotide polymorphism genotyping for six previously established disease risk alleles in the hypoxia-inducible factor-1α-vascular endothelial growth factor pathway was performed in a pediatric cohort with HCM. Findings were correlated with echocardiographic parameters of systolic and diastolic myocardial deformation measured by two-dimensional (2-D) speckle-tracking strain. RESULTS: Twenty-five children (6.1 ± 4.5 years; 69% male) with phenotypic and genotypic (60%) HCM were included. Out of six risk alleles tested, one, VEGF1 963GG, showed an association with reduced regional systolic and diastolic left ventricular (LV) myocardial deformation. Moreover, LV average and segmental systolic and diastolic strain and strain rate were significantly reduced, as assessed by the standardized difference, in patients harboring the risk allele. CONCLUSIONS: This is the first study to identify an association between a risk allele in the VEGF pathway and regional LV myocardial function, with the VEGF1 963GG allele associated with reduced LV systolic and diastolic myocardial performance. While studies are needed to link this information to adverse clinical outcomes, this knowledge may help in risk stratification and patient management in HCM. IMPACT: Risk allele in the VEGF gene impacts on LV myocardial deformation phenotype in children with HCM. LV 2-D strain is significantly reduced in patients with risk allele compared to non-risk allele patients within HCM patient groups. Describes that deficiencies in LV myocardial performance in children with HCM are associated with a previously identified risk allele in the angiogenic transcription factor VEGF. First study to identify an association between a risk allele in the VEGF pathway and regional LV myocardial deformation measured by 2-D strain in children with HCM.

Can We Still Improve Survival Outcomes of Neonatal Biventricular Repairs?

BACKGROUND: We sought to identify modifiable factors to improve survival of neonatal biventricular repair by analyzing the cause of death and predictors of mortality and reintervention in the last 2 decades. METHODS: Between 1995 and 2016, 991 consecutive neonates were included. The cohort was divided by era: era I was from 1995 to 1999, era II 2000 to 2007, and era III 2008 to 2016. The Kaplan-Meier method was used to estimate freedom from death and reintervention. Univariable and multivariable Cox regression was applied to assess predictors for mortality or reintervention in the contemporary cohorts (2000-2016). RESULTS: Median age was 8 days (range, 5-13), and median body weight at operation was 3.3 kg (range, 2.9-3.6). The most common diagnosis was transposition with intact ventricular septum (32%), followed by transposition with ventricular septal defect (14.5%), and simple left-to-right shunt lesion (10.9%). There was significant improvement in survival from era I to eras II and III but no difference between eras II and III (1 year: 82.1% vs 89.4% vs 89.6%, respectively; P < .001). The most common cause of death was sudden death in eras I and III and cardiac in era II. Multivariable analysis revealed preoperative (P = .005)/postoperative (P < .001) extracorporeal membrane oxygenation and postoperative renal replacement (P < .001) as independent predictors for mortality. The reintervention rates were comparable between eras II and III (P = .53). Atrioventricular septal defects and common atrial trunk were identified as predictors for reintervention. CONCLUSIONS: Survival after neonatal biventricular repair remained unchanged. Preventing sudden death, myocardial protection, and minimizing residual lesions are potential targets to improve outcomes.

Low-Molecular-Weight Heparin vs Warfarin for Thromboprophylaxis in Children With Coronary Artery Aneurysms After Kawasaki Disease: A Pragmatic Registry Trial.

BACKGROUND: The substantial risk of thrombosis in large coronary artery aneurysms (CAAs) (maximum z-score ≥ 10) after Kawasaki disease (KD) mandates effective thromboprophylaxis. We sought to determine the effectiveness of anticoagulation (low-molecular-weight heparin [LMWH] or warfarin) for thromboprophylaxis in large CAAs. METHODS: Data from 383 patients enrolled in the International KD Registry (IKDR) were used. Time-to-event analysis was used to account for differences in treatment duration and follow-up. RESULTS: From diagnosis onward (96% received acetylsalicylic acid concomitantly), 114 patients received LMWH (median duration 6.2 months, interquartile range [IQR] 2.5-12.7), 80 warfarin (median duration 2.2 years, IQR 0.9-7.1), and 189 no anticoagulation. Cumulative incidence of coronary artery thrombosis with LMWH was 5.7 ± 3.0%, with warfarin 6.7 ± 3.7%, and with no anticoagulation 20.6 ± 3.0% (P < 0.001) at 2.5 years after the start of thromboprophylaxis (LMWH vs warfarin HR 1.5, 95% confidence interval [CI] 0.4-5.1; P = 0.56). A total of 51/63 patients with coronary artery thrombosis received secondary thromboprophylaxis (ie, thromboprophylaxis after a previous thrombus): 27 LMWH, 24 warfarin. There were no differences in incidence of further coronary artery thrombosis between strategies (HR 2.9, 95% CI 0.6-13.5; P = 0.19). Severe bleeding complications were generally rare (1.6 events per 100 patient-years) and were noted equally for patients on LMWH and warfarin (HR 2.3, 95% CI 0.6-8.9; P = 0.25). CONCLUSIONS: LMWH and warfarin appear to have equivalent effectiveness for preventing thrombosis in large CAAs after KD, although event rates for secondary thromboprophylaxis and safety outcomes were low. Based on our findings, all patients with CAA z-score ≥ 10 should receive anticoagulation, but the choice of agent might be informed by secondary risk factors and patient preferences.

Comparison of Heart Transplantation Outcomes: Adult Congenital Heart Disease vs Matched Cardiac Patients in a Quaternary Reference Centre.

BACKGROUND: The number of transplantations performed for adult congenital heart disease (ACHD) patients is increasing. We sought to compare survival and post-transplantation complications, including graft failure, rejection, dialysis, and use of a right ventricular assist device, between ACHD and a cohort of dilated (DCM) and ischemic (ICM) cardiomyopathy patients matched by age and year of transplantation. METHODS: We retrospectively reviewed our single-institution heart transplantation database and selected all patients who had surgery from 1988 to 2017. In our primary analysis, we looked at survival and post-transplantation complications across cardiomyopathy groups. Our secondary analysis was matched to mitigate era effects as well as differences in age at transplant. RESULTS: We analyzed a cohort consisting of 303 heart transplant patients with cardiomyopathy due to either 1) ACHD (n = 38), 2) ICM (n = 110), or 3) DCM (n = 155). Kaplan-Meier analysis and a multivariable Cox proportional hazard regression model were used for all-cause mortality, and cause-specific hazard regression for cause-specific mortality and morbidity. There was no statistically significant survival difference across groups. The 1-year survival was 68.5% for ACHD, 85.4% for ICM, and 85.5% for DCM. In multivariable analysis, ICM and DCM patients showed a 66% lower risk of death relative to the ACHD group. The matched analysis showed no significant difference in survival across groups. CONCLUSIONS: ACHD patients represent a growing high-risk patient cohort referred for transplantation. To improve survival outcomes we need to address modifiable risk factors.

Human leukocyte antigen-G donor-recipient matching of the 14-base pair polymorphism protects against cancer after heart transplant.

BACKGROUND: After a transplant, cancer is a leading cause of morbidity and mortality. Human leukocyte antigen-G (HLA-G)-an immune checkpoint molecule-reduces allograft rejection by dampening host immune responses. Reports suggest malignant cells utilize HLA-G to evade the immune system and promote cancer development. Our objective was to evaluate HLA-G donor-recipient polymorphism matching and development of cancer after a heart transplant. METHODS: Recipients (n = 251) and corresponding donors (n = 196) were genotyped retrospectively to identify HLA-G polymorphisms in the 5' regulatory (-725, -201), 3' untranslated (+3,197, +3,187, +3,142, 14-base pair insertion-deletion polymorphism [14-bp indel]) and coding regions (Haplotypes I-VI). Associations between donor-recipient polymorphism matching and development of cancer were assessed through multivariate proportional hazard regression models. RESULTS: Recipient and donor (48.2 ± 12.1 and 35.5 ± 14.3 years, respectively) mean follow-up was 7.2 ± 4.6 years. Overall, 42 (16.7%) recipients developed de novo post-transplant cancer. 14-bp polymorphism matching significantly reduced the proportion of cancer, revealing an independent protective effect (hazard ratio [95% CI]: 0.26 [0.10-0.75]; p = 0.012). Recipients with the 14-bp insertion sequence, whether homozygous or heterozygous, had a lower proportion of cancer (p > 0.008), matching the INS sequence (INS/INS and INS/DEL) protected against cancer (p = 0.002). No differences were seen between matched vs unmatched cohorts regarding all donor-recipient pre-transplant and post-transplant characteristics. No other polymorphisms showed significant associations. CONCLUSIONS: We investigated donor-recipient HLA-G polymorphism matching and development of cancer following a heart transplant. Donor-recipient 14-bp matching was an independent protective factor against cancer development. HLA-G may have a role in therapeutic and diagnostic strategies against cancer. Identifying relevant HLA-G polymorphisms may warrant alterations in immunotherapy to reduce post-transplant cancer risk.

ST2 Predicts Risk of Unplanned Readmission Within 1 Year After Pediatric Congenital Heart Surgery.

BACKGROUND: Approximately 10% to 20% of children are readmitted after congenital heart surgery. Very little is known about biomarkers as predictors of risk of unplanned readmission after pediatric congenital heart surgery. Novel cardiac biomarker ST2 may be associated with risk of unplanned readmission. ST2 concentrations are believed to reflect cardiovascular stress and fibrosis. Our objective was to explore the relationship between pre- and postoperative ST2 biomarker levels and risk of readmission within 1 year after congenital heart surgery. METHODS: We prospectively enrolled pediatric patients aged < 18 years who underwent at least 1 congenital heart operation at Johns Hopkins Hospital from 2010 to 2014. Plasma samples were collected immediately before surgery and at the end of bypass. We used Kaplan-Meier survival analysis and multivariable Cox regression models to adjust for variables used in The Society of Thoracic Surgeons Congenital Heart Surgery Database mortality risk model. RESULTS: Of our cohort of 145 patients, we found 39 children with readmissions within 365 days. The median time to unplanned readmission was 54 days (interquartile range, 10-153). Kaplan-Meier analysis demonstrated a significant difference across terciles of pre- and postoperative ST2 biomarker levels. After adjustment, elevated serum levels of ST2 measured preoperatively and postoperatively were associated with increased risk of readmission (hazard ratio, 2.5-3.7; all P < .05). CONCLUSIONS: Elevated levels of ST2 are significantly associated with increased risk of unplanned readmission within 1 year after pediatric congenital heart surgery. Novel serum biomarker ST2 can be used for risk stratification or estimating postsurgical prognosis.

Rapid Advancement in Enteral Nutrition Does Not Affect Systemic Inflammation and Insulin Homeostasis Following Pediatric Cardiopulmonary Bypass Surgery.

OBJECTIVES: To determine impact of enteral nutrition delivery on the relationship among inflammation, insulin resistance, and outcomes following pediatric cardiopulmonary bypass surgery. DESIGN: Pilot, randomized study analyzed according to intention-to-treat analysis. SETTING: Pediatric cardiac ICU. PATIENTS: Infants (≤ 6 mo) undergoing cardiopulmonary bypass. INTERVENTIONS: Patients randomly assigned to receive rapid escalation to enteral nutrition reaching goal feeds by 27 hours or standard feeding practice reaching goal feeds by 63 hours. Feeds were initiated on the first postoperative day. MEASUREMENTS AND MAIN RESULTS: Fifty patients were randomized equally to study arms. Patients were a median (interquartile range) of 16 days old (7-110 d old), undergoing biventricular surgery (88%) with a median cardiopulmonary bypass time of 125 minutes (105-159 min). Serial blood samples were drawn before and after cardiopulmonary bypass, cardiac ICU admission, and every 12 hours (up to 96 hr) for glucose, insulin, and cytokines (interleukin-1α, interleukin-6, interleukin-8, interleukin-10, and tumor necrosis factor-α) levels. Glucose-insulin ratio was calculated to quantify insulin resistance. Patient characteristics, time to enteral nutrition initiation, enteral nutrition interruptions, and insulin administration were similar across intervention arms. FF reached goal feeds at similar intervals as standard feeding (39 hr [30-60 hr] vs 60 hr [21-78 hr]; p = 0.75). No difference in cytokine, insulin, or glucose-insulin ratio was noted between groups. Higher inflammation was associated with increased glucose-insulin ratio and higher risk of adverse events. In multivariable models of interleukin-8, FF was associated with increased glucose-insulin ratio (estimate of effect [95% CI], 0.152 [0.033-0.272]; p = 0.013). Although higher interleukin-8 was associated with an elevated risk of adverse event, this relationship was possibly mitigated by FF (odds ratio [95% CI], 0.086 [0.002-1.638]; p = 0.13). CONCLUSIONS: A FF strategy was not associated with changes to early enteral nutrition delivery. Inflammation, insulin resistance, and morbidity were similar, but FF may modify the relationship between inflammation and adverse event. Multicenter nutrition studies are possible and necessary in this vulnerable population.

Left Ventricular Size and Outcomes in Patients With Left Ventricular Ejection Fraction Less Than 20.

BACKGROUND: The interactive relationship between left ventricular (LV) ejection fraction (LVEF) and LV size in predicting perioperative outcomes after cardiac surgery has not been clarified. METHODS: This study reviewed all patients who underwent cardiac surgery between 2010 and 2016 with either preserved LVEF (>60%; n = 5685) or severely reduced LVEF (<20%; n = 143). LV size was categorized by using either LV end-diastolic or end-systolic diameter or a qualitative assessment, as follows: normal, smaller than 4 cm; mildly enlarged, 4.1 to 5.4 cm moderately enlarged, 5.5 to 6.5 cm; and severely enlarged, larger than 6.5 cm. Using propensity-score analysis, we matched patients with LVEF less than 20% (n = 143) in a 3:1 ratio with patients with LVEF greater than 60% (n = 429). RESULTS: There were significant differences in mortality, major morbidity, and operative mortality and prolonged length of stay between patients with LVEF less than 20% and LVEF greater than 60%. In patients with LVEF less than 20%, there were no significant differences in outcomes between those with an LV size of 5.4 cm or smaller and an LV size of 5.5 cm or larger. In patients undergoing isolated coronary artery bypass grafting (CABG), LV size predicted mortality, major morbidity, and operative mortality (odds ratio, 5.5 [95% confidence interval, 2.0 to 15.7]; P < .001) and prolonged length of stay (odds ratio, 3.4 [95% confidence interval, 1.2 to 10.3]; P = .026), respectively. CONCLUSIONS: LVEF is more important than LV size in predicting outcomes after cardiac surgery. However, in patients undergoing isolated CABG, LV size has an interactive effect with LVEF and can potentially aid the decision-making process. Risk adjustment models using only LVEF may be inaccurate, particularly with respect to isolated CABG procedures.

Machine Learning Identifies Clinical and Genetic Factors Associated With Anthracycline Cardiotoxicity in Pediatric Cancer Survivors.

BACKGROUND: Despite known clinical risk factors, predicting anthracycline cardiotoxicity remains challenging. OBJECTIVES: This study sought to develop a clinical and genetic risk prediction model for anthracycline cardiotoxicity in childhood cancer survivors. METHODS: We performed exome sequencing in 289 childhood cancer survivors at least 3 years from anthracycline exposure. In a nested case-control design, 183 case patients with reduced left ventricular ejection fraction despite low-dose doxorubicin (≤250 mg/m2), and 106 control patients with preserved left ventricular ejection fraction despite doxorubicin >250 mg/m2 were selected as extreme phenotypes. Rare/low-frequency variants were collapsed to identify genes differentially enriched for variants between case patients and control patients. The expression levels of 5 top-ranked genes were evaluated in human induced pluripotent stem cell-derived cardiomyocytes, and variant enrichment was confirmed in a replication cohort. Using random forest, a risk prediction model that included genetic and clinical predictors was developed. RESULTS: Thirty-one genes were differentially enriched for variants between case patients and control patients (p < 0.001). Only 42.6% case patients harbored a variant in these genes compared to 89.6% control patients (odds ratio: 0.09; 95% confidence interval: 0.04 to 0.17; p = 3.98 × 10-15). A risk prediction model for cardiotoxicity that included clinical and genetic factors had a higher prediction accuracy and lower misclassification rate compared to the clinical-only model. In vitro inhibition of gene-associated pathways (PI3KR2, ZNF827) provided protection from cardiotoxicity in cardiomyocytes. CONCLUSIONS: Our study identified variants in cardiac injury pathway genes that protect against cardiotoxicity and informed the development of a prediction model for delayed anthracycline cardiotoxicity, and it also provided new targets in autophagy genes for the development of cardio-protective drugs. (Preventing Cardiac Sequelae in Pediatric Cancer Survivors [PCS2]; NCT01805778).

Long-term outcomes of chordal replacement with expanded polytetrafluoroethylene sutures to repair mitral leaflet prolapse.

OBJECTIVES: This study examines the durability of mitral valve (MV) repair for mitral regurgitation using chordal replacement with expanded polytetrafluoroethylene sutures to correct leaflet prolapse. METHODS: Isolated chordal replacement was used to correct prolapse in 186 (24.9%) patients and combined with leaflet resection in 560 (75.1%). Patients were followed prospectively with periodical clinical and echocardiographic assessments for a median follow-up of 11 years (range, 7-16 years). RESULTS: Patients' median age was 58 years (range, 48-67 years) and 516 (69.2%) were men. Bileaflet prolapse was present in 63% of patients and advanced myxomatous degeneration was present in 32%. The number of neochords per repaired valve increased over time and was not associated with MV reoperation or recurrent mitral regurgitation. The cumulative incidence of MV reoperation with death as a competing risk was 4.2% (95% confidence interval [CI], 2.4-6.0) at 20 years. Multivariable analysis revealed that previous cardiac operations (hazard ratio, 5.70; 95% CI, 1.96-16.53; P = .001), and isolated anterior leaflet prolapse (hazard ratio, 3.92; 95% CI, 1.106-13.91; P = .034) were associated with increased hazard of MV reoperation. The probability of recurrent moderate or severe mitral regurgitation using repeated measures regression models was 14.1% (95% CI, 10.3-19.0) at 20 years. Variables associated with recurrent MR in multivariable regression analysis were left ventricular ejection <40% (hazard ratio, 3.57; 95% CI, 1.37-9.32; P = .009) and preoperative complete heart block (hazard ratio, 5.90; 95% CI, 2.47-14.09; P < .001). CONCLUSIONS: Chordal replacement with expanded polytetrafluoroethylene sutures provides stable MV function in most patients during the first 2 decades of follow-up.

Feeding May Modulate the Relationship Between Systemic Inflammation, Insulin Resistance, and Poor Outcome Following Cardiopulmonary Bypass for Pediatric Cardiac Surgery.

BACKGROUND: Hyperglycemia is common following cardiopulmonary bypass (CPB) surgery and is associated with poor outcomes, often attributed to hyperinsulinemia and an acquired state of insulin resistance. This study examined the underpinnings of hyperglycemia and the effects of nutrition on the association with inflammation and clinical outcomes. METHODS: This prospective, observational cohort study enrolled consecutive children (<18 years) undergoing CPB. Serial measurements of inflammatory cytokines, glucose, insulin, and nutrition delivery were obtained. Glucose-insulin ratio (G:I) was calculated for each time point as a measure of insulin resistance (lower G:I reflects higher resistance). Clinical outcomes were recorded using a composite morbidity score. RESULTS: The 200 subjects studied were predominantly females (58%) undergoing biventricular repair (85%) at a median (interquartile range) age of 0.58 years (0.28, 3.4) and weight of 7.0 kg (3.1, 59.5). Hyperglycemia was common (49% of patients), coinciding with peak cytokine concentrations. Insulin levels were highest and G:I lowest immediately following separation from CPB but had no consistent relationship with cytokines. The morbidity outcome was reached by 23% of patients, with increased odds associated with higher interleukin (IL)6 and IL8 levels but not by glucose, insulin, or G:I. Providing higher feeding volumes attenuated this association between inflammation and morbidity. Higher feeds were not associated with G:I but appeared to decrease the strength of the relationship between cytokines and glycemic indices. CONCLUSION: Postoperative morbidity is independently associated with increased inflammation but not with hyperglycemia or markers of insulin resistance. Higher feeding volume may modify these relationships and have a protective role.