Clinical Interventions and Hemodynamic Monitoring in the Setting of Left Ventricular Systolic Heart Failure in Children: Insights From a Physiologic Simulator.

BACKGROUND: In pediatric critical care, vasoactive/inotropic support is widely used in patients with heart failure, but it remains controversial because the influence of multiple medications and the interplay between their inotropic and vasoactive effects on a given patient are hard to predict. Robust evidence supporting their use and quantifying their effects in this group of patients is scarce. STUDY QUESTION: The aim of this study was to characterize the effect of vasoactive medications on various cardiovascular parameters in pediatric patient with decreased ejection fraction. STUDY DESIGN: Clinical-data based physiologic simulator study. MEASURE AND OUTCOMES: We used a physics-based computer simulator for quantifying the response of cardiovascular parameters to the administration of various types of vasoactive/inotropic medications in pediatric patients with decreased ejection fraction. The simulator allowed us to study the impact of increasing medication dosage and the simultaneous administration of some vasoactive agents. Correlation and linear regression analyses yielded the quantified effects on the vasoactive/inotropic support. RESULTS: Cardiac output and systemic venous saturation significantly increased with the administration of dobutamine and milrinone in isolation, and combination of milrinone with dobutamine, dopamine, or epinephrine. Both parameters decreased with the administration of epinephrine and norepinephrine in isolation. No significant change in these hemodynamic parameters was observed with the administration of dopamine in isolation. CONCLUSIONS: Milrinone and dobutamine were the only vasoactive medications that, when used in isolation, improved systemic oxygen delivery. Milrinone in combination with dobutamine, dopamine, or epinephrine also increased systemic oxygen delivery. The induced increment on afterload can negatively affect systemic oxygen delivery.

Postoperative Atrioventricular Block in Pediatric Patients: Impact of Congenital Cardiac Malformations and Medications.

Postoperative atrioventricular block may occur after pediatric cardiac surgery. A small proportion of those who develop atrioventricular block will require pacemaker placement. The primary aim of this study was to determine factors associated with postoperative atrioventricular block. Secondary aims included determining factors associated with pacemaker placement in those with atrioventricular block. Data from the PHIS data were utilized to identify patients under 18 years of age who underwent cardiac surgery. Those who did and did not develop atrioventricular block. Univariable analyses and regression analyses were conducted to determine factors associated with postoperative atrioventricular block. Similar analyses were conducted to determine factors associated with pacemaker placement in those with atrioventricular block. A total of 43,716 admissions were identified. Of these, 2093 (5%) developed atrioventricular block and 480 (1% of total admissions) underwent pacemaker placement. Approximately 70% of those with atrioventricular block received steroids but this was not associated with a decrease in pacemaker placement. Risk factors (congenital malformations of the heart, comorbidities, medications) associated with increased risk of atrioventricular block and pacemaker placement were identified. Postoperative atrioventricular block occurred in 5% of pediatric admissions for cardiac surgery. Of these admissions with postoperative atrioventricular block, 23% required pacemaker placement. Isoproterenol and steroids were not associated with a reduction in the likelihood of pacemaker placement.

Association Between Congenital Heart Disease and Stroke: Insights from a National Database.

To delineate prevalence of stroke in the pediatric intensive care unit and to determine risk factors for stroke and association of stroke with mortality in patients with congenital heart disease. Retrospective cohort study. Patients admitted to pediatric intensive care units in the USA participating in the Pediatric Health Information System database from 2016 to 2021. Patients were categorized as those who experienced ischemic or hemorrhagic stroke and those with congenital heart disease. We performed univariate and multivariate logistic regressions to determine risk factors associated with stroke and then developed a predictive model for stroke development in patients with congenital heart disease. Of 426,029 admissions analyzed, 4237 (0.9%) patients experienced stroke and 1197 (1.4%) of 80,927 patients with congenital heart disease developed stroke (odds ratio 1.15, 95% confidence interval 1.06-1.24). Patients with congenital heart disease, younger age, extracorporeal membrane oxygenation, mechanical ventilation, and cardiac arrest were most strongly associated with increased risk of stroke. Stroke increased odds of mortality for patients with congenital heart disease (odds ratio 2.49, 95% confidence interval 2.08-2.98). A risk score greater than 0 was associated with a 33.3% risk of stroke for patients with congenital heart disease (negative predictive value of 99%, sensitivity 69%, specificity 63%). Children with congenital heart disease are at increased risk for developing stroke, which is associated with increased mortality. Early identification of the most vulnerable patients may enable providers to implement preventative measures or rapid treatment strategies to prevent neurologic morbidity.

Reduced length of stay after implementation of a clinical pathway following repair of ventricular septal defect.

BACKGROUND: There is variation in care and hospital length of stay following surgical repair of ventricular septal defects. The use of clinical pathways in a variety of paediatric care settings has been shown to reduce practice variability and overall length of stay without increasing the rate of adverse events. METHODS: A clinical pathway was created and used to guide care following surgical repair of ventricular septal defects. A retrospective review was done to compare patients two years prior and three years after the pathway was implemented. RESULTS: There were 23 pre-pathway patients and 25 pathway patients. Demographic characteristics were similar between groups. Univariate analysis demonstrated a significantly shorter time to initiation of enteral intake in the pathway patients (median time to first enteral intake after cardiac ICU admission was 360 minutes in pre-pathway patients and 180 minutes in pathway patients, p < 0.01). Multivariate regression analyses demonstrated that the pathway use was independently associated with a decrease in time to first enteral intake (-203 minutes), hospital length of stay (-23.1 hours), and cardiac ICU length of stay (-20.5 hours). No adverse events were associated with the use of the pathway, including mortality, reintubation rate, acute kidney injury, increased bleeding from chest tube, or readmissions. CONCLUSIONS: The use of the clinical pathway improved time to initiation of enteral intake and decreased length of hospital stay. Surgery-specific pathways may decrease variability in care while also improving quality metrics.

Factors that mediate change in creatinine and acute kidney injury after the Norwood operation: insights from high-fidelity haemodynamic monitoring data.

BACKGROUND: Acute kidney injury is a common postoperative complication of paediatric cardiac surgery associated with increased morbidity and mortality. The purpose of this study is to characterise associations between haemodynamic parameters, clinical parameters, and medical interventions, on acute kidney injury. METHODS: Nine patients with univentricular physiology undergoing the Norwood procedure from a single-centre tertiary care paediatric cardiac ICU were included (September 2022 to March 2023). Patients were monitored with the T3 software. Data were analysed using a Fisher exact test, Mann-Whitney-U test, LASSO-based machine learning techniques, and receiver operator curve analyses. RESULTS: Over 27,000 datapoints were included. Acute kidney injury occurred in 2 patients (22%) during this period. Net fluid balance and renal oxygen extraction were independently associated with acute kidney injury, while commonly used metrics of pressure (systolic, diastolic, or mean arterial blood pressure) were not. The resulting acute kidney injury risk score was (4.1 × fluid balance) + (1.9 × renal oxygen extraction). The risk score was significantly higher in acute kidney injury with a score of 32.9 compared to 7.9 (p < 0.01). Optimal cut-offs for fluid balance (7 mL/hr) and renal oxygen extraction (29%) were identified. Higher serum creatinine:baseline creatinine ratio was associated with a higher mean airway pressure, higher renal oxygen extraction, higher mean arterial blood pressure, higher vasoactive inotropic score, and fluid balance. CONCLUSION: Among patients with univentricular physiology undergoing the Norwood procedure, renal oxygen extraction and a higher net fluid balance are independently associated with increased risk of acute kidney injury. Renal perfusion pressure is not significantly associated with acute kidney injury.

Comorbidities, pharmacologic interventions, and mechanical interventions associated with mortality in isolated diastolic left heart failure: lessons from a national database.

BACKGROUND: Diastolic heart failure may be noted in paediatric patients with CHD, cardiomyopathy, or malignancies requiring chemotherapy, but the available data are scarce, and often derived from adult trials or based on theoretic or anecdotal evidence. METHODS: Data between 2016 and 2021 were obtained from Pediatric Health Information System database. Patients <18 years of age with isolated diastolic heart failure admitted to ICU at some point during admission were included. They were divided into patients with and without inpatient mortality. Patients' demographics, comorbidities using ICD-10 codes, and pharmacologic interventions were also recorded. Univariate analysis was done in demographics, comorbidities, pharmacologic interventions, and mechanical interventions between admissions with and without mortality. Multivariable logistic regression was done for inpatient mortality and multivariable linear regression was done for total hospital length of stay in survivors. RESULTS: Isolated diastolic heart failure comprised 0.5% of critically ill paediatric patients. A total of 121 (5%) experienced mortality among the 2,273 admissions in the final analyses. Milrinone and angiotensin converting enzyme inhibitor were found to be associated with decreased mortality. Increasing age and diuretics were associated with decreased total hospital length of stay in survivors. CONCLUSION: In the cohort studied, isolated diastolic left heart failure has a 5% mortality. Several comorbidities and interventions are associated with increased mortality with milrinone and angiotensin converting enzyme inhibitors being associated with decreased risk of mortality. When only admissions with survival to discharge are considered, older age and diuretics are associated with lower total hospital length of stay.

Estimation of the inferior caval vein saturation using high-fidelity non-invasive haemodynamic values and validation of modelled estimates.

OBJECTIVES: Monitoring venous saturation allows identification of inadequate systemic oxygen delivery. The aim was to develop a model using non-invasive haemodynamic variables to estimate the inferior caval vein saturation and to determine its prognostic utility. METHODS: This is a single-centre, retrospective study. A Bayesian Pearson's correlation was conducted to model the inferior caval vein saturation. Next, a Bayesian linear regression was conducted for data from all the patients and from only those with parallel circulation. Venous saturation estimations were developed. The correlation of these estimates to the actual inferior caval vein saturation was assessed. The resulting models were then applied to two validation cohorts: biventricular circulation (arterial switch operation) and parallel circulation (Norwood operation). RESULTS: One hundred and thirteen datasets were collected across 15 patients. Of which, 65% had parallel circulation. In all patients, the measured and estimated inferior caval vein saturations had a moderate and significant correlation with a coefficient of 0.64. In patients with parallel circulation, the measured and estimated inferior caval vein saturation had a moderate and significant correlation with a coefficient of 0.61. In the biventricular circulation cohort, the estimated inferior caval vein saturation had an area under the curve of 0.71 with an optimal cut-off of 49. In the parallel circulation cohort, the estimated interior caval vein saturation had an area under the curve of 0.83 with an optimal cut-off of 24%. CONCLUSION: The inferior caval vein saturation can be estimated utilising non-invasive haemodynamic data. This estimate has correlation with measured inferior caval vein saturations and offers prognostic utility.

Factors associated with renal oxygen extraction in mechanically ventilated children after the Norwood operation: insights from high fidelity haemodynamic data.

BACKGROUND: Maintaining the adequacy of systemic oxygen delivery is of utmost importance, particularly in critically ill children. Renal oxygen extraction can be utilised as metric of the balance between systemic oxygen delivery and oxygen consumption. The primary aim of this study was to determine what clinical factors are associated with renal oxygen extraction in children after Norwood procedure. METHODS: Mechanically ventilated children who underwent Norwood procedure from 1 September, 2022 to 1 March, 2023 were identified as these patients had data collected and stored with high fidelity by the T3 software. Data regarding haemodynamic values, fluid balance, and airway pressure were collected and analysed using Bayesian regression to determine the association of the individual metrics with renal oxygen extraction. RESULTS: A total of 27,270 datapoints were included in the final analyses. The resulting top two models explained had nearly 80% probability of being true and explained over 90% of the variance in renal oxygen extraction. The coefficients for each variable retained in the best were -1.70 for milrinone, -19.05 for epinephrine, 0.129 for mean airway pressure, -0.063 for mean arterial pressure, 0.111 for central venous pressure, 0.093 for arterial saturation, 0.006 for heart rate, -0.025 for respiratory rate, 0.366 for systemic vascular resistance, and -0.032 for systemic blood flow. CONCLUSION: Increased milrinone, epinephrine, mean arterial pressure, and systemic blood flow were associated with decreased (improved) renal oxygen extraction, while increased mean airway pressure, central venous pressure, arterial saturation, and systemic vascular resistance were associated with increased (worsened) renal oxygen extraction.

Poor correlation of venous lactate with systemic oxygen saturation in the paediatric cardiac ICU: a pilot study.

INTRODUCTION: Cardiac intensive care providers require a comprehensive understanding of cardiac output and oxygen delivery. The estimation of cardiac output in clinical practice often relies on thermodilution and the Fick principle. Central venous saturation and lactate levels are commonly used indicators for cardiac output assessment. However, the relationship between venous lactate levels and venous oxygen saturation in paediatric cardiac intensive care patients remains unclear. METHODS: This is a single-centre retrospective pilot study aimed to investigate the correlation between venous lactate and venous oxygen saturation in paediatric patients. Data collected included venous saturation, heart rate, mean arterial blood pressure, arterial saturation by pulse oximetry, cerebral and renal near-infra-red spectroscopy values, and the presence of a functionally univentricular heart. Statistical analyses included Bayesian Pearson correlation and regression analyses. RESULTS: A total of 203 data points from 37 unique patients were included in the analysis. There was no significant correlation between serum lactate and venous saturation (correlation coefficient = -0.01; Bayes factor 10 = 0.06). Serum lactate also did not correlate with other haemodynamic metrics. Venous saturation showed correlations with arterial saturation and cerebral and renal near-infra-red spectroscopy. Regression analysis revealed that parallel circulation, arterial saturation, and cerebral near-infra-red spectroscopy were predictive of venous saturation. The following equation resulted from the regression analysis: 68.0 - (12.7 x parallel circulation) - (0.8 x arterial saturation) + (0.3 x cerebral near-infra-red spectroscopy). This model had a Bayes factor 10 of 0.03 and adjusted R-squared was 0.29. CONCLUSION: In paediatric cardiac intensive care patients, there is no significant correlation between venous lactate and venous saturation, suggesting that lactate may not be a reliable marker for assessing the adequacy of oxygen delivery in this population. Only a weak correlation could be identified once the venous saturation was 70% or lower. Additional research is needed to explore alternative markers for monitoring oxygen delivery in critically ill paediatric patients.

Rare association of aortic atresia with balanced superior-inferior ventricles: case report of successful neonatal biventricular repair and review of the literature.

Aortic atresia is a rare finding and has not been previously described with superior-inferior ventricles. Presented here is a case of a heart with these concomitant findings and review of reported cases of aortic atresia in the absence of hypoplastic left heart syndrome. The aim of this report is to help highlight associated findings and the clinical approach taken. Also highlighted is the importance of not mistaking aortic atresia for common arterial trunk.

Predicting inpatient mortality in pediatric traumatic brain injury: insights from a national database.

PURPOSE: The purpose of this study was to determine factors significantly associated with mortality and length of stay (LOS) in admissions to the pediatric intensive care unit (PICU) for traumatic brain injury (TBI). METHODS: A cross-sectional, retrospective cohort study that identified PICU admissions with TBI from forty-nine hospitals in the USA using the Pediatric Health Information System database from 2016 to 2021. Univariable analyses comparing those who did and did not experience mortality were performed. The following regression analyses were conducted: logistic regression with mortality as dependent variable; linear regression with LOS as the dependent variable; logistic regression with mortality as the dependent variable but only included patients with cerebral edema; and linear regression with LOS as the dependent variable but only included patients who survived. From the regression analysis for mortality in all TBI patients was utilized to develop a mortality risk score. RESULTS: A total of 3041 admissions were included. Those with inpatient mortality (18.5%) tended to be significantly younger (54 vs. 92 months, p < 0.01), have < 9 pediatric Glasgow Coma Scale on admission (100% vs. 52.9%, p < 0.01) and more likely to experience acute renal, hepatic and respiratory failure, acidosis, central diabetes insipidus, hyperkalemia, and hypocalcemia. Regression analysis identified that pediatric Glasgow Coma Scale, alkalosis and cardiac arrest significantly increased risks of mortality. The TBI mortality risk score had an area under the curve of 0.89 to identify those with mortality; a score of 6 ≤ was associated with 88% mortality. CONCLUSION: Patients admitted to the PICU with TBI have 18.5% risk of inpatient mortality with most occurring the first 48 h and these are characterized with greater multisystem organ dysfunction, received medical and mechanical support. TBI mortality risk score suggested is a practical tool to identify patients with an increase likelihood to die.

The Inadequate Oxygen Delivery Index and Its Correlation with Venous Saturation in the Pediatric Cardiac Intensive Care Unit.

Continuous monitoring software, T3, has an integrated index called the inadequate oxygen delivery index 50% (IDO2-50) which displays a probability that the mixed venous saturation is below a user-selected threshold of 30-50%. The primary aim of this study was to determine the correlation of the IDO2-50 with a measured venous saturation. The secondary aim of this study was to characterize the hemodynamic factors that contributed to the IDO2-50. This single-center, retrospective study aimed to characterize the correlation between IDO2-50 and inferior vena cava (IVC) saturation. A Bayesian Pearson correlation was conducted to assess the correlation between the collected variables of interest, with a particular interest in the correlation between the IDO2-50 and the IVC saturation. Receiver operator curve (ROC) analysis to assess the ability of the IDO2-50 to identify when the venous saturation was less than 50%. Bayesian linear regression was done with the IDO2-50 (dependent variable) and other independent variables. A total of 113 datasets were collected across 15 unique patients. IDO2-50 had moderate correlation with the IVC saturation (correlation coefficient - 0.569). The IDO2-50 had a weak but significant correlation with cerebral near-infrared spectroscopy (NIRS) values, a weak but significant correlation with heart rate, and a moderate and significant correlation with arterial saturation. ROC analysis demonstrated that the IDO2-50 had a good ability to identify a venous saturation below 50%, with an area under the curve of 0.797, cutoff point of 24.5 with a sensitivity of 81%, specificity of 66%, positive predictive value of 44%, and negative predictive value of 91%. Bayesian linear regression analysis yielded the following model: 237.82 + (1.18 × age in months) - (3.31 × arterial saturation) - (1.92 × cerebral NIRS) + (0.84 × heart rate). The IDO2 index has moderate correlation with IVC saturation. It has good sensitive and negative predictive value. Cerebral NIRS does appear to correlate better with the underlying venous saturation than the IDO2 index.

Acute Effects of Sacubitril/Valsartan with Initial Initiation in Pediatric Patients in the Cardiac Intensive Care Unit.

There are very few objectively studied and proven medical interventions for the management of pediatric heart failure. Due to improvement in morbidity and mortality in the adult heart failure population, sacubitril/valsartan has started to be used in pediatric patients. The aim of this study was to characterize the acute cardiovascular effects of sacubitril/valsartan in the first 48 h after initiation. Single center retrospective study of pediatric patients in the cardiac intensive care unit who were initiated on sacubitril/valsartan for the first time over a three-year period. Clinical data was collected immediately prior to and within 48 h following initiation. A total of 16 patients with a mean age of 9.6 years were started on sacubitril/valsartan with a mean daily dose of 1.6 mg/kg/day in the first 48 h. Significant decreases were noted in N-terminal brain natriuretic peptide and vasoactive-inotrope score. No significant changes were noted in other clinical variables. The initiation of sacubitril/valsartan in a small cohort of pediatric patients with heart failure in the cardiac intensive care unit is associated with a significant decrease in N-terminal brain natriuretic peptide with a concurrent decrease in vasoactive-inotrope score and without significant change venous oxygen extraction ratio or other hemodynamic variables.

Descriptors of Failed Extubation in Norwood Patients Using Physiologic Data Streaming.

The objective of this study is to evaluate the utility of high-frequency physiologic data during the extubation process and other clinical variables for describing the physiologic profile of extubation failure in neonates with hypoplastic left heart syndrome (HLHS) post-Norwood procedure. This is a single-center, retrospective analysis. Extubation events were collected from January 2016 until July 2021. Extubation failure was defined as the need for re-intubation within 48 h of extubation. The data included streaming heart rate, respiratory rate, blood pressure, arterial oxygen saturation, and cerebral/renal near-infrared spectroscopy (NIRS). The most recent blood laboratory results before extubation were also included. These markers, demographics, clinical characteristics, and ventilatory settings were compared between successful and failed extubations. The analysis included 311 extubations. The extubation failure rate was 10%. According to univariable analyses, failed extubations were preceded by higher respiratory rates (p = 0.029), lower end-tidal CO2 (p = 0.009), lower pH (p = 0.043), lower serum bicarbonate (p = 0.030), and lower partial pressure of O2 (p = 0.022). In the first 10 min after extubation, the failed events were characterized by lower arterial (p = 0.028) and cerebral NIRS (p = 0.018) saturations. Failed events were associated with persistently lower values for cerebral NIRS 2 h post-extubation (p = 0.027). In multivariable analysis, vocal cord anomaly, cerebral NIRS at 10 min post-extubation, renal NIRS at pre-extubation and post-extubation, and end-tidal CO2 at pre-extubation remained as significant co-variables. Oximetric indices before, in the 10 min immediately after, and 2 h after extubation and vocal cords paralysis are associated with failed extubation events in patients with parallel circulation.

Randomized Controlled Trials in Pediatric Cardiology: A Power Struggle?

Sample size and statistical power are often limited in pediatric cardiology studies due to the relative infrequency of specific congenital malformations of the heart and specific circulatory physiologies. The primary aim of this study was to determine what proportion of pediatric cardiology randomized controlled trials achieve an 80% statistical power. Secondary aims included characterizing reporting habits in these studies. A systematic review was performed to identify pertinent pediatric cardiology randomized controlled trials. The following data were collected: publication year, journal, if "power" or "sample size" were mentioned if a discrete, primary endpoint was identified. Power analyses were conducted to assess if the sample size was adequate to demonstrate results at 80% power with a p-value of less than 0.05. A total of 83 pediatric cardiology randomized controlled trials were included. Of these studies, 48% mentioned "power" or "sample size" in the methods, 49% mentioned either in the results, 12% mentioned either in the discussion, and 66% mentioned either at any point in the manuscript. 63% defined a discrete, primary endpoint. 38 studies (45%) had an adequate sample size to demonstrate differences with 80% power at a p-value of less than 0.05. A majority of these are not powered to reach the conventionally accepted 80% power target. Adequately powered studies were found to be more likely to report "power" or "sample size" and have a discrete, primary endpoint.

Fluid Overload and AKI After the Norwood Operation: The Correlation and Characterization of Routine Clinical Markers.

The purpose of this study was to determine the correlation of different methods of assessing fluid overload and determine which metrics are associated with development of acute kidney injury (AKI) in the period immediately following Norwood palliation. This was a retrospective single-center study of Norwood patients from January 2011 through January 2021. AKI was defined using the Kidney Disease Improving Global Outcomes (KDIGO). Patients were separated into two groups: those with AKI and those without. A logistic regression analysis was conducted with AKI at any point in the study period as the dependent variable and clinical and laboratory data as independent variables. Analysis was conducted as a stepwise regression. The coefficients from the logistic regression were then used to develop a cumulative AKI risk score. Spearman correlations were conducted to analyze the correlation of fluid markers. 116 patients were included, and 49 (42.4%) developed AKI. The duration of open chest, duration of mechanical ventilation, need for dialysis, need for extracorporeal membrane oxygenation, and inpatient mortality were associated with AKI (p ≤ 0.05). Stepwise logistic regression demonstrated the following significant independent associations AKI: age at Norwood in days (p < 0.01), blood urea nitrogen (p < 0.01), central venous pressure (p = 0.04), and renal oxygen extraction ratio (p < 0.01). The area under the receiver operating characteristic curve for the logistic regression was 0.74. The fluid markers had weak R-value. Urea, central venous pressure, and renal oxygen extraction ratio are associated with AKI after the Norwood operation. Common clinical metrics used to assess fluid overload are poorly correlated with each other for postoperative Norwood patients.

Effect of Carnitine Supplementation in Pediatric Patients with Left Ventricular Dysfunction.

Carnitine is an essential amino acid involved in transporting fatty acids across the mitochondrial membrane. Fatty acids are a primary source of energy for the myocardium. Studies in adults demonstrated decreased carnitine levels in the ischemic myocardium, but subsequent exogenous carnitine supplementation showed improvement of myocardial metabolism and left ventricular function. However, only limited data regarding carnitine are available in pediatrics. A single-center retrospective, paired data study was conducted. Patients < 18 years, left ventricular ejection fraction (LVEF) < 55% by echocardiography, and had received at least 7 days of oral or intravenous carnitine supplementation between January 2018 and March 2021 are included in the study. Several endpoints and covariates were collected for each patient: before, one week after, one month after, and 6 months after carnitine supplementation. Univariate analysis consisted of an analysis of variance (ANOVA), followed by an analysis of covariance (ANCOVA) to model LVEF while adjusting for other variables. 44 patients included in the final analyses. LVEF significantly improved from 50.5 to 56.6% (p < 0.01). When LVEF was adjusted for other interventions (mechanical ventilation, afterload reduction, diuretic therapy, spironolactone), the estimated means demonstrated a significant increase from 45.7 to 58.0% (p < 0.01). Free carnitine level increased significantly (p = 0.03), and N-terminal-pro-brain natriuretic peptide (p = 0.03), creatinine (p < 0.01), and lactate (p < 0.01) all significantly decreased over the study period. Carnitine supplementation in pediatric patients with left ventricular systolic dysfunction may be associated with an increase in LVEF and improvement in laboratory markers of myocardial stress and cardiac output.

Association Between Seasonal Fontan Timing, Viral Infection Burden, and Post-Operative Length of Stay.

The Fontan procedure (FP) is typically a semi-elective surgery performed between 2 and 5 years of age to complete staged single ventricle palliation. Optimal timing for the FP, particularly in relation to seasonal infectious burden, remains unclear. We queried the Pediatric Health Information System (PHIS) database for all admissions for viral respiratory infections (VRI) from January 2006 to September 2015 and separately for all admissions with a primary procedure code of FP. The PHIS query generated 2,767,142 admissions for VRI and 6349 admissions for the FP from 45 children's hospitals. Of all FP, 2124 (33.5%) were performed from October through March. The median length of stay after Fontan procedure was 9 days (IQR 7-15). Median length of stay after FP was correlated with VRI burden (correlation coefficient = 0.3, p = 0.03). April through August (weeks 18 through 35) had the lowest VRI admission burden and FP length of stay was significantly shorter during this time (13.6 ± 14.8 days vs 14.9 ± 20.3 days, p = 0.03). The FP is frequently performed during the viral respiratory season. This timing is associated with an increased post-operative length of stay after the FP. For elective FP, ideal timing that avoids the viral respiratory season and minimizes post-operative LOS is April through August.

Echocardiographic Strain to Predict Need for Transplant or Mortality in Fontan Patients with Hypoplastic Left Heart Syndrome.

Despite recent advances, hypoplastic left heart syndrome (HLHS) patients subsequent to the Fontan still have significant morbidity and mortality. Some require heart transplant due to systemic ventricular dysfunction. Limited data exist on timing for transplant referral. This study aims to correlate systemic ventricular strain by echocardiography to transplant-free survival. HLHS patients who had Fontan palliation at our institution were included. Patients were divided into: 1) Required transplant or experienced mortality (composite end point); 2) Did not require transplant or survived. For those who experienced the composite endpoint, the last echocardiogram prior to the composite outcome was used, while for those who did not experience the composite endpoint the last echocardiogram obtained was used. Several qualitative and quantitative parameters were analyzed with focus on strain parameters. Ninety-five patients with HLHS Fontan palliation were identified. Sixty-six had adequate images and eight (12%) experienced transplant or mortality. These patients had greater myocardial performance index by flow Doppler (0.72 versus 0.53, p = 0.01), higher systolic/diastolic duration ratio (1.51 versus 1.13, p = 0.02), lower fractional area change (17.65 versus 33.99, p < 0.01), lower global longitudinal strain (GLS) (-8.63 versus - 17.99, p < 0.01), lower global longitudinal strain rate (GLSR) (- 0.51 versus - 0.93, p < 0.01), lower global circumferential strain (GCS) (-6.68 versus -18.25, p < 0.01), and lower (GCSR) global circumferential strain rate (-0.45 versus -1.01, p < 0.01). ROC analysis demonstrated predictive value for GLS - 7.6 (71% sensitive, 97% specific, AUC 81%), GLSR -0.58 (71% sensitive, 88% specific, AUC 82%), GCS - 10.0 (86% sensitive, 91% specific, AUC 82%), and GCSR -0.85 (100% sensitive, 71% specific, AUC 90%). GLS and GCS can help predict transplant-free survival in patients with hypoplastic left heart syndrome having undergone Fontan palliation. Higher strain values (closer to zero) may be a helpful tool in determining when transplant evaluation is warranted in these patients.

Haemodynamic and clinical variables after surgical systemic to pulmonary artery shunt placement versus arterial ductal stenting.

BACKGROUND: Transcatheter stenting of the arterial duct is an alternative to surgical systemic to pulmonary artery shunt in neonates with parallel circulation. The current study compares haemodynamic and laboratory values in these patients for the first 48 hours after either intervention. METHODS: Neonates with ductal dependent pulmonary blood flow who underwent surgical shunt placement or catheter-based arterial ductal stent placement between January 2013 and January 2022 were identified. Haemodynamic variables included heart rate, blood pressure, near infrared spectroscopy, central venous pressure, vasoactive inotropic score, and arterial saturation. Laboratory variables collected included blood urea nitrogen, serum creatinine, and serum lactate. Variables were collected at baseline, upon post-procedural admission, 6 hours after admission, 12 hours after admission, and 48 hours after admission. Secondary outcomes included post-procedural mechanical ventilation duration, post-procedural hospital length of stay, need for reintervention, need for extracorporeal membrane oxygenation, cardiac arrest, and inpatient mortality. RESULTS: Of the 52 patients included, 38 (73%) underwent shunt placement while 14 (27%) underwent a stent placement. Heart rates, renal oxygen extraction ratio, and cerebral oxygen extraction ratio were significantly lower in the stent group (p = <0.01, 0.01, and < 0.01, respectively).Haemoglobin and vasoactive inotropic scores were significantly lower in the stent group (p = <0.01, <0.01, respectively). The stent group had increased risk for cardiac arrest (p = 0.04). CONCLUSION: Patients who undergo arterial ductal stent placement have lower heart rates, haemoglobin, renal oxygen extraction ratio, cerebral oxygen extraction ratio, and vasoactive inotropic score in the first 48 hours post-procedure compared to patients with shunt placement.