Pre-operative Imaging of Critical Coarctation of the Aorta: Impact on Surgical Approach and Outcomes.

Computed tomographic angiography (CTA) has been increasingly used for the evaluation of infants with aortic arch hypoplasia and coarctation of the aorta. The goals of this study were to compare echocardiographic and CTA findings in critical coarctation of the aorta, to evaluate each modality's influence on surgical approach for repair and determine if pre-operative measurements or surgical approach are associated with residual lesions/re-interventions. This was a single-center retrospective cohort study that included 85 neonates and infants who underwent repair of coarctation/arch hypoplasia by three months of age. Two groups were compared: patients with pre-operative echocardiograms only and patients with both echocardiogram and CTA evaluations. 44 (52%) patients received an echocardiogram and CTA, and 41 (48%) patients received an echocardiogram only. Patients in the CTA + echo group had smaller mitral valve and ascending aorta measurements (p = 0.01). When comparing CTA to echocardiogram measurements, the aortic valve annulus, ascending aorta, proximal and distal transverse arch, and isthmus were smaller on echo (p < 0.01). A smaller aortic valve annulus and aortic root as well as thoracotomy approach were associated with residual gradients/re-intervention (p < 0.01). Our study found that patients who underwent CTA preoperatively had smaller left-sided structures. Aortic measurements were smaller on echocardiogram when compared to CTA. Smaller left-sided structures proximal to the aortic arch and thoracotomy predicted the development of residual lesions/re-intervention. CTA is useful in the surgical planning for neonates with arch hypoplasia/coarctation and may help risk stratify for residual lesions/re-intervention.

"Fontan Conduit Stent-Angioplasty and Progression of Fontan-Associated Liver Disease".

Patients with Fontan circulation insidiously develop congestive hepatopathy related to chronically reduced cardiac output and central venous hypertension, also known as Fontan-associated liver disease (FALD). Fontan pathway obstruction is increasingly detected and may accelerate FALD. The impact of conduit stent angioplasty on FALD is unknown. Retrospective, single-center review of patients with Fontan circulation who underwent conduit stent angioplasty at cardiac catheterization over 5-year period. Demographics and cardiac histories were reviewed. Labs, liver ultrasound elastography, echocardiogram, hemodynamic and angiographic data at catheterization were recorded pre- and post-stent angioplasty. Primary outcome was change in hepatic function via MELD-XI scores and liver stiffness (kPa), with secondary outcomes of ventricular function, BNP, and repeat catheterization hemodynamics. 33 patients underwent Fontan conduit stent angioplasty, 19.3 ± 7.0 years from Fontan operation. Original conduit diameter was 19.1 ± 1.9 mm. Prior to angioplasty, conduit size was reduced to a cross-sectional area 132 (91, 173) mm2 and increased to 314 (255, 363) mm2 post-stent. Subjects' baseline median MELD-XI of 11 (9, 12) increased to 12 (9, 13) at 19 ± 15.5 months post-angioplasty (n = 22, p = 0.053). There was no significant change in liver stiffness at 12.1 ± 8.9 months post-angioplasty (n = 15, p = 0.13). Median total bilirubin significantly increased (1.4 [0.9, 1.8]), from baseline 1.1 [0.7, 1.5], p = 0.04), as did median BNP (41 [0, 148] from baseline 34 [15, 79]; p = 0.02). There were no significant changes in ventricular function or repeat invasive hemodynamics (n = 8 subjects). Mid-term follow-up of Fontan subjects post-conduit stent angioplasty did not show improvements in non-invasive markers of FALD.

Outcomes of Gastrostomy and Tracheostomy in Infants Undergoing Truncus Arteriosus Repair: Database Study Using the Pediatric Health Information System.

OBJECTIVES: We sought to determine the prevalence of and factors associated with gastrostomy tube placement and tracheostomy in infants undergoing truncus arteriosus repair, and associations between these procedures and outcome. DESIGN: Retrospective cohort study. SETTING: Pediatric Health Information System database. PATIENTS: Infants less than 90 days old who underwent truncus arteriosus repair from 2004 to 2019. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Multivariable logistic regression models were used to identify factors associated with gastrostomy tube and tracheostomy placement and to identify associations between these procedures and hospital mortality and prolonged postoperative length of stay (LOS; > 30 d). Of 1,645 subjects, gastrostomy tube was performed in 196 (11.9%) and tracheostomy in 56 (3.4%). Factors independently associated with gastrostomy tube placement were DiGeorge syndrome, congenital airway anomaly, admission age less than or equal to 2 days, vocal cord paralysis, cardiac catheterization, infection, and failure to thrive. Factors independently associated with tracheostomy congenital airway anomaly, truncal valve surgery, and cardiac catheterization. Gastrostomy tube was independently associated with prolonged postoperative LOS (odds ratio [OR], 12.10; 95% CI, 7.37-19.86). Hospital mortality occurred in 17 of 56 patients (30.4%) who underwent tracheostomy versus 147 of 1,589 patients (9.3%) who did not ( p < 0.001), and median postoperative LOS was 148 days in patients who underwent tracheostomy versus 18 days in those who did not ( p < 0.001). Tracheostomy was independently associated with mortality (OR, 3.11; 95% CI, 1.43-6.77) and prolonged postoperative LOS (OR, 9.85; 95% CI, 2.16-44.80). CONCLUSIONS: In infants undergoing truncus arteriosus repair, tracheostomy is associated with greater odds of mortality; while gastrostomy and tracheostomy are strongly associated with greater odds of prolonged postoperative LOS.

Association Between Birth Weight Z-Scores and Early Outcomes Following Truncus Arteriosus Repair.

In infants undergoing truncus arteriosus (TA) repair, we sought to determine associations between fetal growth restrictions as measured by birth weight Z-score and early outcomes. We utilized the Pediatric Health Information System (PHIS) database to identify infants < 90 days old who underwent TA repair from 2004 to 2019. The primary exposure variable was birth weight Z-score, calculated based on gestational age at birth, gender, and birth weight. The primary outcome was postoperative hospital mortality. Secondary outcomes included major complications, prolonged postoperative length of hospital stay (LOS; > 30 days), and hospital readmission within 1 year. Generalized estimating equation (GEE) models were used to identify adjusted associations between birth weight Z-score, small for gestational age (SGA) status, and mortality and included were 1039 subjects. Median birth weight was 2960 g, gestational age at birth was 38 weeks, and birth weight Z-score was - 0.47. SGA was present in 21% of subjects. Hospital mortality occurred in 104 patients (10%). By multivariable analysis, lower birth weight Z-score was associated with higher hospital mortality [for each unit decrease in birth weight Z-score below - 1.0, adjusted OR 1.71 (95% CI 1.10-4.25)]. SGA status was associated with increased hospital mortality (adjusted OR 2.17; 95% CI 1.39-3.40). Birth weight Z-scores and SGA status were not significantly associated with occurrence of cardiac arrest, ECMO use, gastrostomy tube placement, tracheostomy, seizures, infection, prolonged postoperative LOS, or hospital readmission. In infants undergoing TA repair, lower birth weight Z-scores and SGA status were strongly associated with increased hospital mortality.

Timing of surgical repair and resource utilisation in infants with complete atrioventricular septal defect.

INTRODUCTION: Variation exists in the timing of surgery for balanced complete atrioventricular septal defect repair. We sought to explore associations between timing of repair and resource utilisation and clinical outcomes in the first year of life. METHODS: In this retrospective single-centre cohort study, we included patients who underwent complete atrioventricular septal defect repair between 2005 and 2019. Patients with left or right ventricular outflow tract obstruction and major non-cardiac comorbidities (except trisomy 21) were excluded. The primary outcome was days alive and out of the hospital in the first year of life. RESULTS: Included were 79 infants, divided into tertiles based on age at surgery (1st = 46 to 137 days, 2nd = 140 - 176 days, 3rd = 178 - 316 days). There were no significant differences among age tertiles for days alive and out of the hospital in the first year of life by univariable analysis (tertile 1, median 351 days; tertile 2, 348 days; tertile 3, 354 days; p = 0.22). No patients died. Fewer post-operative ICU days were used in the oldest tertile relative to the youngest, but days of mechanical ventilation and hospitalisation were similar. Clinical outcomes after repair and resource utilisation in the first year of life were similar for unplanned cardiac reinterventions, outpatient cardiology clinic visits, and weight-for-age z-score at 1 year. CONCLUSIONS: Age at complete atrioventricular septal defect repair is not associated with important differences in clinical outcomes or resource utilisation in the first year of life.

The pediatric heart network's study on long-term outcomes of children with HLHS and the impact of Norwood Shunt type in the single ventricle reconstruction trial cohort (SVRIII): Design and adaptations.

BACKGROUND: The Single Ventricle Reconstruction (SVR) Trial was the first randomized clinical trial of a surgical approach for treatment of congenital heart disease. Infants with hypoplastic left heart syndrome (HLHS) and other single right ventricle (RV) anomalies were randomized to a modified Blalock Taussig Thomas shunt (mBTTS) or a right-ventricular-to-pulmonary-artery shunt (RVPAS) at the time of the Norwood procedure. The aim of the Long-term Outcomes of Children with HLHS and the Impact of Norwood Shunt Type (SVR III) study is to compare early adolescent outcomes including measures of cardiac function, transplant-free survival, and neurodevelopment, between those who received a mBTTS and those who received an RVPAS. METHODS: Transplant-free survivors of the SVR cohort were enrolled at 10 to 15 years of age for multifaceted in-person evaluation of cardiac function (cardiac magnetic resonance [CMR], echocardiogram and exercise test) and neurodevelopmental evaluation. Right ventricular ejection fraction measured by CMR served as the primary outcome. Development of arrhythmias, protein losing enteropathy, and other comorbidities were assessed through annual medical history interview. Through the course of SVR III, protocol modifications to engage SVR trial participants were designed to enhance recruitment and retention. CONCLUSIONS: Evaluation of long-term outcomes will provide important data to inform decisions about the shunt type placed at the Norwood operation and will improve the understanding of cardiovascular and neurodevelopmental outcomes for early adolescents with HLHS.

Changes in circumferential strain can differentiate pediatric heart transplant recipients with and without graft rejection.

BACKGROUND: Routine surveillance protocols rely heavily on endomyocardial biopsy (EMB) for detection of rejection in pediatric heart transplant recipients. More sensitive echocardiographic tools to assess rejection may help limit the number of EMBs. This study compared changes in left ventricular (LV) strain in patients who had rejection versus those who did not. METHODS: A single center retrospective review was conducted between 2013 and 2020. Patients were categorized based on rejection history. Echocardiograms were evaluated at the time of 2 consecutive EMBs; in the rejection group, the second echocardiogram was collected at the time of a rejection episode. Conventional measures of LV function and speckle-tracking echocardiography-derived longitudinal (LS) and circumferential strain (CS) were measured. RESULTS: 17 patients were in the non-rejection group and 17 were in the rejection group (30 total rejection episodes). The rejection group was older at the time of transplant (12.5 vs. 1.3 years, p = .01). A decline in CS was seen in the rejection group at the second echocardiogram [-18.5 (IQR -21.5, -14.6) to -15.7 (IQR -19.8, -13.2)] while CS improved in the non-rejection group [-20.8 (IQR -23.9, -17.8) to -23.9 (IQR -24.9, -20.1)]. This difference in change reached significance (p = .02). A similar pattern was seen in LS that neared significance (p = .06). There was no significant difference in ejection fraction change (p = .24). CONCLUSIONS: Patients in the non-rejection group displayed improvement in CS between echocardiograms while patients in the rejection group showed subsequent decline. Worsening of LV CS may help identify acute rejection in the early post-transplant period.

QRS fragmentation and prolongation as predictors of exercise capacity in patients after Fontan palliation.

INTRODUCTION: Patients with Fontan anatomy are at increased risk for exercise intolerance and early morbidity and mortality. QRS complex fragmentation (fQRS) and prolongation have been studied in multiple heart diseases, but their clinical importance is unknown in the Fontan population. METHODS: A retrospective cross-sectional study was performed. ECGs were evaluated for QRS prolongation (>98 percentile for age) and fQRS (≥3 R-waves/notches in the R/S complex [more than two in RBBB] in ≥2 contiguous leads). The primary outcome measures were CPET performance. RESULTS: Total 90 patients (median age 18 years, 57% male, 59% RV dominant) were included; 13% had fQRS and 31% had prolonged QRS. Demographically, patients with fQRS or prolonged QRS were like those without. Peak VO2 (64% vs. 63%, p .45), VE/VCO2 slope (85% vs. 88%, p = .74), and O2 pulse (149% vs. 129%, p = .83) were similar in the fQRS group versus those without. Upon multi-variable regression, body mass index (ß = -0.38, p < .01) and QRS duration (ß = -0.29, p < .01) were independently associated with % predicted VO2; fQRS was not. Lower cardiac index (2.2 vs. 2.8 L/min/m2 , p = .03) and higher ventricular end-diastolic pressure (13 vs. 10 mmHg, p = .02) was seen with fQRS. CONCLUSIONS: QRS fragmentation is present in patients with Fontan physiology. fQRS showed no association with CPET performance but was related to invasive hemodynamic markers of ventricular performance. QRS duration may be a better predictor of exercise function following Fontan.

Longitudinal Observational Study of Cardiac Outcome Risk Factor Prediction in Children, Adolescents, and Adults with Barth Syndrome.

Barth Syndrome (BTHS) is an X-linked mitochondrial cardioskeletal myopathy caused by defects in TAFAZZIN, a gene responsible for cardiolipin remodeling. Altered mitochondrial levels of cardiolipin lead to cardiomyopathy (CM), muscle weakness, exercise intolerance, and mortality. Cardiac risk factors predicting outcome are unknown. Therefore, we conducted a longitudinal observational study to determine risk factors for outcome in BTHS. Subjects with minimum two evaluations (or one followed by death or transplant) were included. Cardiac size, function, and QTc data were measured by echocardiography and electrocardiography at 7 time points from 2002 to 2018. Analysis included baseline, continuous, and categorical variables. Categorical risk factors included prolonged QTc, abnormal right ventricle fractional area change (RV FAC), left ventricle (LV) or RV non-compaction, and restrictive CM phenotype. The association between variables and cardiac death or transplant (CD/TX) was assessed. Median enrollment age was 7 years (range 0.5-22; n = 44). Transplant-free survival (TFS) was 74.4% at 15 years from first evaluation. The cohort demonstrated longitudinal declines in LV size and stroke volume z-scores (end-diastolic volume, p = 0.0002; stroke volume p < 0.0001), worsening RV FAC (p = 0.0405), and global longitudinal strain (GLS) (p = 0.0001) with stable ejection (EF) and shortening (FS) fraction. CD/TX subjects (n = 9) displayed worsening LV dilation (p = 0.0066), EF (p ≤ 0.0001), FS (p = 0.0028), and RV FAC (p = .0032) versus stability in TFS. Having ≥ 2 categorical risk factors predicted CD/TX (p = 0.0073). Over 15 years, 25% of BTHS subjects progressed to CD/TX. Those with progressive LV enlargement, dysfunction, and multiple cardiac risk factors warrant increased surveillance and intense therapy.

Calcium Chloride Infusions are Not Associated with Improved Outcomes in Neonates Undergoing Cardiac Operations.

Neonatal cardiac performance is dependent on calcium delivery to the myocardium. Little is known about the use and impact of calcium chloride infusions in neonates who undergo cardiac surgery. We hypothesized that the use of calcium chloride infusions would decrease the doses required of traditional inotropic and vasoactive medications by supporting cardiac output in this patient population. We performed a single-institution, retrospective, cohort study. All neonates (≤ 30 days old) undergoing cardiac surgery from 06/01/2015 through 12/31/2018 were included. Patients were divided into two groups: those who received postoperative calcium chloride infusions (calcium group) and those who did not (control group). The primary outcome was the occurrence of a maximum Vasoactive Inotropic Score (VIS) > 15 in the first 24 h following surgery. One hundred and thirty-five patients met inclusion criteria. Sixty-six patients received postoperative calcium infusions and 69 patients did not. Gestational age, weight at surgery, age at surgery, surgical complexity and cardiopulmonary bypass times were similar between groups. Forty-two (70%) patients receiving calcium had a postoperative maximum VIS > 15 compared with 38 (55%) patients not on a calcium infusion (p = 0.08). There were no differences in postoperative length of ventilation, time to enteral feeding, hospital LOS, or operative mortality between groups. Calcium chloride infusions in neonates who underwent cardiac surgery did not decrease exposure to other inotropic and vasoactive agents in the first 24 post-operative hours or improve patient outcomes.

Factors associated with caregiver adherence to mobile health interstage home monitoring in infants with single ventricle or biventricular shunt-dependent heart disease.

Mobile health technology is an emerging tool in interstage home monitoring for infants with single ventricle heart disease or biventricular shunt-dependent defects. This study sought to describe adherence to mobile health monitoring and identify factors and outcomes associated with adherence to mobile health monitoring. This was a retrospective, single-institution study of infants who were followed in a mobile health-based interstage home monitoring programme between February 2016 and October 2020. The analysis included 105 infants and subjects were grouped by frequency of adherence to mobile health monitoring. Within the study cohort, 16 (15.2%) had 0% adherence, 25 (23.8%) had <50% adherence, and 64 (61.0%) had >50% adherence. The adherent groups had a higher percentage of infants who were male (p = 0.02), white race (p < 0.01), non-Hispanic or non-Latinx ethnicity (p < 0.01) and had mothers with primary English fluency (p < 0.01), married marital status (p < 0.01), and a prenatal diagnosis of faetal cardiac disease (p = 0.03). Adherent groups also had a higher percentage of infants with non-Medicaid primary insurance (p < 0.01) and residence in a neighbourhood with a higher median household income (p < 0.04). Frequency of adherence was not associated with interstage mortality, unplanned cardiac reinterventions, or hospital readmissions. Impact of mobile health interstage home monitoring on caregiver stress as well as use of multi-language, low literacy, affordable mobile health options for interstage home monitoring warrant further investigation.

Preoperative in-hospital mortality in neonates with critical CHD.

OBJECTIVE: Data regarding preoperative mortality in neonates with critical CHD are sparse and would aid patient care and family counselling. The objective of this study was to utilise a multicentre administrative dataset to report the rate of and identify risk factors for preoperative in-hospital mortality in neonates with critical CHD across US centres. STUDY DESIGN: The Pediatric Health Information System database was utilised to search for newborns ≤30 days old, born 1 January 2009 to 30 June 2018, with an ICD-9/10 code for d-transposition of the great arteries, truncus arteriosus, interrupted aortic arch, or hypoplastic left heart syndrome. Preoperative in-hospital mortality was defined as patients who died prior to discharge without an ICD code for cardiac surgery or interventional catheterisation. RESULTS: Overall preoperative mortality rate was at least 5.4% (690/12,739) and varied across diagnoses (d-TGA 2.9%, TA 8.3%, IAA 5.5%, and HLHS 7.3%) and centres (0-20.5%). In multivariable analysis, risk factors associated with preoperative mortality included preterm delivery (<37 weeks) (OR 2.3, 95% CI: 1.8-2.9; p < 0.01), low birth weight (<2.5 kg) (OR 3.8, 95% CI: 3.0-4.7; p < 0.01), and genetic abnormality (OR 1.6, 95% CI: 1.2-2.2; p < 0.01). Centre average surgical volume was not a significant risk factor. CONCLUSION: Approximately 1 in 20 neonates with critical CHD suffered preoperative in-hospital mortality, and rates varied across diagnoses and centres. Better understanding of the factors that drive the variation (e.g. patient factors, preoperative care models, surgical timing) could help identify patient care improvement opportunities and inform conversations with families.

Height Versus Body Surface Area to Normalize Cardiovascular Measurements in Children Using the Pediatric Heart Network Echocardiographic Z-Score Database.

Normalizing cardiovascular measurements for body size allows for comparison among children of different ages and for distinguishing pathologic changes from normal physiologic growth. Because of growing interest to use height for normalization, the aim of this study was to develop height-based normalization models and compare them to body surface area (BSA)-based normalization for aortic and left ventricular (LV) measurements. The study population consisted of healthy, non-obese children between 2 and 18 years of age enrolled in the Pediatric Heart Network Echo Z-Score Project. The echocardiographic study parameters included proximal aortic diameters at 3 locations, LV end-diastolic volume, and LV mass. Using the statistical methodology described in the original project, Z-scores based on height and BSA were determined for the study parameters and tested for any clinically significant relationships with age, sex, race, ethnicity, and body mass index (BMI). Normalization models based on height versus BSA were compared among underweight, normal weight, and overweight (but not obese) children in the study population. Z-scores based on height and BSA were calculated for the 5 study parameters and revealed no clinically significant relationships with age, sex, race, and ethnicity. Normalization based on height resulted in lower Z-scores in the underweight group compared to the overweight group, whereas normalization based on BSA resulted in higher Z-scores in the underweight group compared to the overweight group. In other words, increasing BMI had an opposite effect on height-based Z-scores compared to BSA-based Z-scores. Allometric normalization based on height and BSA for aortic and LV sizes is feasible. However, height-based normalization results in higher cardiovascular Z-scores in heavier children, and BSA-based normalization results in higher cardiovascular Z-scores in lighter children. Further studies are needed to assess the performance of these approaches in obese children with or without cardiac disease.

Infantile dilated cardiomyopathy due to congenital left main coronary ostial stenosis.

Although a rare form of congenital heart disease, anomalies of the coronary arteries can present as heart failure in infants. The most common lesion is an anomalous left coronary artery arising from the pulmonary artery, but other abnormalities can present similarly. This case is an infant who is found to have left coronary ostial stenosis causing dilated cardiomyopathy.

Improved outcomes after implementation of a specialized pediatric cardiac rapid response team.

INTRODUCTION: The efficacy of a specialized pediatric cardiac rapid response team is unknown. We hypothesized that a specialized cardiac rapid response team would facilitate team-wide communication between the cardiac stepdown unit and cardiac intensive care unit (ICU) teams and improve patient care. MATERIALS AND METHODS: A specialized pediatric cardiac rapid response team was implemented in June 2015. All pediatric cardiac rapid response team activations and outcomes from implementation through December 2018 were reviewed. Cardiac arrests and unplanned transfers to the cardiac ICU were indexed to 1000 patient-days to account for inpatient volume trends and evaluated over time. RESULTS: There were 202 cardiac rapid response team activations in 108 unique patients during the study period. After implementation of the pediatric cardiac rapid response team, unplanned transfers from the cardiac stepdown unit to the cardiac ICU decreased from 16.8 to 7.1 transfers per 1000 patient days (p = 0.012). The stepdown unit cardiac arrest rate decreased from 1.2 to 0.0 arrests per 1000 patient-days (p = 0.015). There was one death on the cardiac stepdown unit in the 5 years since the implementation of the cardiac rapid response team, compared to four deaths in the previous 5 years. CONCLUSIONS: A reduction in unplanned cardiac ICU transfers, cardiac arrests, and mortality on the cardiac stepdown unit has been observed since the implementation of a specialized pediatric cardiac rapid response team. A specialized cardiac rapid response team may improve communication and empower the interdisciplinary care team to escalate care for patients experiencing clinical decline.

A transition clinic intervention to improve follow-up rates in adolescents and young adults with congenital heart disease.

BACKGROUND: Children with congenital heart disease (CHD) require lifelong cardiology follow-up. Many experience gaps in care around the age of transition to adult-oriented care with associated comorbidity. We describe the impact of a clinic-based intervention on follow-up rates in this high-risk population. METHODS: Patients ≥11 years seen in a paediatric outpatient CHD Transition Clinic completed self-assessment questionnaires, underwent focused teaching, and were followed on a clinic registry with assessment of care continuation. The cohort "lost to follow-up" rate, defined as absence from care at least 6 months beyond the recommended timeframe, was compared with a control group. Secondary outcomes included questionnaire scores and adult cardiology referral trends. RESULTS: Over 26 months, 53 participants completed an initial Transition Clinic visit; 43% (23/53) underwent a second visit. Median participant age was 18.0 years (interquartile range 16.0, 22.0). The cohort's "lost to follow-up" rate was 7.3%, which was significantly lower than the control rate (25.9%, p < 0.01). Multivariable regression analyses demonstrated clinic participation as the only factor independently associated with follow-up rates (p = 0.048). Transition readiness was associated with older age (p = 0.01) but not sex, univentricular heart, interventional history, or surgical complexity. One-third of adult participants transferred to adult care. CONCLUSIONS: A CHD Transition Clinic intervention can improve follow-up rates in adolescents and young adults. Age is an important factor in transition readiness, and retention of adults in paediatric care appears multi-factorial. We postulate that serial assessments of self-management, focused education, and registry utilisation may improve patient outcomes by reducing lapses in care.

Lean body mass is the strongest anthropometric predictor of left ventricular mass in the obese paediatric population.

BACKGROUND: Indexing left ventricular mass to body surface area or height2.7 leads to inaccuracies in diagnosing left ventricular hypertrophy in obese children. Lean body mass predictive equations provide the opportunity to determine the utility of lean body mass in indexing left ventricular mass. Our objectives were to compare the diagnostic accuracy of predicted lean body mass, body surface area, and height in detecting abnormal left ventricle mass in obese children. METHODS: Obese non-hypertensive patients aged 4-21 years were recruited prospectively. Dual-energy X-ray absorptiometry was used to measure lean body mass. Height, weight, sex, race, and body mass index z-score were used to calculate predicted lean body mass. RESULTS: We enrolled 328 patients. Average age was 12.6 ± 3.8 years. Measured lean body mass had the strongest relationship with left ventricular mass (R2 = 0.84, p < 0.01) compared to predicted lean body mass (R2 = 0.82, p < 0.01), body surface area (R2 = 0.80, p < 0.01), and height2.7 (R2 = 0.65, p < 0.01). Of the clinically derived variables, predicted lean body mass was the only measure to have an independent association with left ventricular mass (ß = 0.90, p < 0.01). Predicted lean body mass was the most accurate scaling variable in detecting left ventricular hypertrophy (positive predictive value = 88%, negative predictive value = 99%). CONCLUSIONS: Lean body mass is the strongest predictor of left ventricular mass in obese children. Predicted lean body mass is the most accurate anthropometric scaling variable for left ventricular mass in left ventricular hypertrophy detection. Predicted lean body mass should be considered for clinical use as the body size correcting variable for left ventricular mass in obese children.

Challenges and lessons learned from the Pediatric Heart Network Normal Echocardiogram Database study.

BACKGROUND: The Pediatric Heart Network Normal Echocardiogram Database Study had unanticipated challenges. We sought to describe these challenges and lessons learned to improve the design of future studies. METHODS: Challenges were divided into three categories: enrolment, echocardiographic imaging, and protocol violations. Memoranda, Core Lab reports, and adjudication logs were reviewed. A centre-level questionnaire provided information regarding local processes for data collection. Descriptive statistics were used, and chi-square tests determined differences in imaging quality. RESULTS: For the 19 participating centres, challenges with enrolment included variations in Institutional Review Board definitions of "retrospective" eligibility, overestimation of non-White participants, centre categorisation of Hispanic participants that differed from National Institutes of Health definitions, and exclusion of potential participants due to missing demographic data. Institutional Review Board amendments resolved many of these challenges. There was an unanticipated burden imposed on centres due to high numbers of echocardiograms that were reviewed but failed to meet submission criteria. Additionally, image transfer software malfunctions delayed Core Lab image review and feedback. Between the early and late study periods, the proportion of unacceptable echocardiograms submitted to the Core Lab decreased (14 versus 7%, p < 0.01). Most protocol violations were from eligibility violations and inadvertent protected health information disclosure (overall 2.5%). Adjudication committee reviews led to protocol changes. CONCLUSIONS: Numerous challenges encountered during the Normal Echocardiogram Database Study prolonged study enrolment. The retrospective design and flaws in image transfer software were key impediments to study completion and should be considered when designing future studies collecting echocardiographic images as a primary outcome.

Factors Associated with Delayed Transition to Oral Feeding in Infants with Single Ventricle Physiology.

OBJECTIVES: To describe the duration of time to achieve exclusive oral feeding in infants with single ventricle physiology and to identify risk factors associated with prolonged gastrostomy tube dependence. STUDY DESIGN: Single center, retrospective study of infants with single ventricle physiology. The primary outcome was duration of time required to achieve oral feeding. Transition periods were defined as exclusive oral feeding by Glenn palliation (early), by 1 year of age (mid), or after 1 year of age (late). RESULTS: Seventy-eight infants were analyzed; 46 (59%) were discharged to home with a gastrostomy tube after the initial hospitalization. Overall, 39 infants (50%) achieved early transition, 14 (18%) mid, and 18 (23%) late. The group who achieved early transition had a higher percentage of preoperative oral feeding (P < .01), greater weight-for-age z score at initial discharge (P = .03), shorter initial intensive care unit duration (P < .01), shorter initial hospital length of stay (P < .01), and greater weight-for-age z score at Glenn admission (P = .02). No preoperative oral feeding (OR = 0.12, P = .02) and greater number of cardiac medications at initial discharge (OR = 3.8, P = .03) were associated with failure to achieve early transition. No preoperative oral feeding (OR = 0.09, P = .01) and longer initial intensive care unit duration (OR = 1.1, P = .03) were associated with failure to achieve mid transition. CONCLUSION: Preoperative oral feeding may potentially be a modifiable factor to help improve early transition to oral feeding.

The Relationship Between Pre-operative Left Ventricular Longitudinal Strain and Post-operative Length of Stay in Patients Undergoing Arterial Switch Operation Is Age Dependent.

INTRODUCTION: Post-operative length of stay (LOS) after the arterial switch operation (ASO) is variable. The association between pre-operative non-invasive measures of ventricular function and post-operative course has not been well established. The aims of this study were to (1) evaluate the relationship between pre-operative non-invasive measures of ventricular function and post-operative LOS and (2) evaluate the change in ventricular function after ASO. METHODS: Data were reviewed in consecutive ASO patients between 2010 and 2016. The primary outcome was post-operative LOS. Echocardiograms obtained during the pre-operative period and at the time of discharge were retrospectively analyzed using speckle-tracking echocardiography. Pearson's correlation between patient-specific, pre-operative, and echocardiographic data versus post-operative LOS was assessed. RESULTS: Fifty-two patients were included in analyses, 39 neonates and 13 infants. Left ventricular (LV) longitudinal strain correlated with post-operative LOS for infants age > 28 days (r = 0.62, p = 0.03), but not for neonates (r = 0.14, p = 0.40). Operative age (r = - 0.42, p = 0.003), weight at surgery (r = - 0.48, p ≤ 0.001), and cardiopulmonary bypass time (r = 0.30, p = 0.045) also correlated with post-operative LOS. Standard 2D measures of ventricular function did not correlate with post-operative LOS. LV ejection fraction and longitudinal strain worsened post-operatively. CONCLUSION: Higher pre-operative LV longitudinal strain (representing worse LV function) is associated with increased post-operative LOS after ASO in infants > 28 days, but not in neonates. LV ejection fraction and longitudinal strain worsened after ASO. Future studies should assess the utility of performing STE in risk stratifying patients prior to ASO.