Mechanical Circulatory Support in Pediatric Myocarditis: Support Strategies and Outcomes in a Nationally Representative Cohort.

Background: Myocarditis is a common cause of pediatric heart failure which may require mechanical circulatory support (MCS). The purpose of this study is to describe MCS strategies used in a nationwide cohort of pediatric patients with myocarditis, identify trends over time, and compare outcomes between MCS strategies. Methods: This study utilized the Kids' Inpatient Database (KID), a national sample of administrative discharge data. KID admissions from 2003-2016 were queried using ICD-9/10 codes to identify those with a diagnosis of myocarditis. MCS outcomes were compared using logistic regression. Results: Of 5,661 admissions for myocarditis, MCS was used in 424 (7.5%), comprised of extracorporeal membrane oxygenation (ECMO) in 312 (73.6%), including 32 (10.2%) instances of extracorporeal cardiopulmonary resuscitation (ECPR), temporary ventricular assist devices (tVAD) in 28 (6.6%), durable VAD (dVAD) in 42 (9.9%) and combination MCS in 42 (9.9%). MCS use increased over time (p=0.031), but MCS strategies did not significantly change. Mortality was high in the MCS group (28.3%). There was no difference in odds of death in the VAD only or combination MCS group compared to the non-ECPR ECMO group (p=0.07 and p=0.65, respectively). Conclusion: MCS is used in 1 in 13 pediatric myocarditis cases, and MCS use is increasing over time with ECMO remaining the most frequently used modality. Mortality remains high in patients that receive MCS but does not differ between those receiving VAD or combination MCS as compared to non-ECPR ECMO on unadjusted analysis. Further prospective analysis is required to evaluate the relative effectiveness of MCS modalities in this disease.

Hybrid stage 1 palliation with simultaneous off-pump ventricular assist device placement in neonates with high-risk single ventricle anatomy: Initial experience.

Background: Infants with single ventricle heart disease and severe atrioventricular valve regurgitation have poor outcomes following conventional staged palliation. As such, ventricular assist device (VAD) placement along with hybrid stage 1 palliation has been proposed as a bridge to heart transplant. We present a novel surgical technique for VAD implantation concurrent with hybrid stage 1 that avoids cardiopulmonary bypass. Methods: We performed a retrospective review of our institutional experience with this novel surgical technique. Results: Three patients (weight, 2.7-3.5 kg; age, 3 to 5 days) underwent hybrid stage 1 with VAD placement, consisting of bilateral 3.5-mm expandable polytetrafluoroethylene (PTFE) pulmonary artery bands, a ductal stent, a 6-mm Berlin Heart outflow cannula onto the main pulmonary trunk with a 10-mm graft, a 6-mm Berlin Heart outflow cannula onto the right atrium, and a 10-mL Berlin Heart pump. In patients with severe aortic arch hypoplasia or coarctation, a 4-mm PTFE graft was sewn from the VAD outflow graft to the innominate artery to protect coronary and cerebral perfusion. Procedures were performed off bypass with minimal blood product use. Patients were extubated on postoperative days 2, 2, and 5. There were no procedural complications. All patients were transferred out of the intensive care unit and demonstrated appropriate weight gain. Anticoagulation strategy was bivalirudin and antiplatelet therapy. The patients underwent transplantation after 149 days, 157 days, and 288 days of support. Conclusions: Off-pump single ventricle VAD placement is technically feasible and can be done at the time of hybrid stage 1 palliation with minimal operative morbidity as a bridge to transplant.

Subspecialty Health Care Utilization in Pediatric Patients With Muscular Dystrophy in the United States.

Background and Objectives: Standards of care exist to optimize outcomes in Duchenne and Becker muscular dystrophy (DBMD), caused by alterations in the DMD gene; however, there are limited data regarding health care access in these patients. This study aims to characterize outpatient subspecialty care utilization in pediatric patients with DBMD. Methods: This retrospective cohort study used administrative claims data from IBM MarketScan Medicaid and Commercial Claims and Encounters Research Databases (2013-2018). Male patients 1-18 years with an ICD-9/10 diagnosis code for hereditary progressive muscular dystrophy between January 1, 2013, and December 31, 2017, were included. Participants were stratified into 3 age cohorts: 1-6 years, 7-12 years, and 13-18 years. The primary outcome was rate of annual neurology visits. Secondary outcomes included annual follow-up rates in other subspecialties and proportion of days covered (PDC) by corticosteroids. Results: A total of 1,386 patients met inclusion-347 (25.0%) age 1-6 years, 502 (36.2%) age 7-12 years, and 537 (38.7%) age 13-18 years. Heart failure, respiratory failure, and technology dependence increased with age (p for all<0.05). The rate of neurology visits per person-year was 0.36 and did not differ by age. Corticosteroid use was low; 30% of person-years (1452/4829) had a PDC ≥20%. Medicaid insurance was independently associated with a lower likelihood of annual neurology follow-up (OR 0.23; 95% CI 0.18-0.28). Discussion: The rate of annual neurology follow-up and corticosteroid use in patients with DBMD is low. Medicaid insurance status was independently associated with a decreased likelihood of neurology follow-up, while age was not, suggesting that factors other than disease severity influence neurology care access. Identifying barriers to regular follow-up is critical in improving outcomes for patients with DBMD.

Characterization of clinical serum cardiac biomarker levels in individuals with Friedreich ataxia.

Friedreich ataxia is a progressive autosomal recessive neurodegenerative disorder characterized by ataxia, dyscoordination, and cardiomyopathy. A subset of patients with Friedreich ataxia have elevated levels of serum cardiac troponin I, but associations with disease outcomes and features of cardiomyopathy remain unclear. In this study, we characterized clinically obtained serum cardiac biomarker levels including troponin I, troponin T, and B-type natriuretic peptide in subjects with Friedreich ataxia and evaluated their association with markers of disease. While unprovoked troponin I levels were elevated in 36% of the cohort, cTnI levels associated with a cardiac event (provoked) were higher than unprovoked levels. In multivariate linear regression models, younger age predicted increased troponin I values, and in logistic regression models younger age, female sex, and marginally longer GAA repeat length predicted abnormal troponin I levels. In subjects with multiple assessments, mean unprovoked troponin I levels decreased slightly over time. The presence of abnormal troponin I values and their levels were predicted by echocardiographic measures of hypertrophy. In addition, troponin I levels predicted long-term markers of clinical cardiac dysfunction over time to a modest degree. Consequently, troponin I values provide a marker of hypertrophy but only a minimally predictive biomarker for later cardiac manifestations of disease such as systolic dysfunction or arrhythmia.

Insights into the effects of Friedreich ataxia on the left ventricle using T1 mapping and late gadolinium enhancement.

BACKGROUND: The left ventricular (LV) changes which occur in Friedreich ataxia (FRDA) are incompletely understood. METHODS: Cardiac magnetic resonance (CMR) imaging was performed using a 1.5T scanner in subjects with FRDA who are homozygous for an expansion of an intron 1 GAA repeat in the FXN gene. Standard measurements were performed of LV mass (LVM), LV end-diastolic volume (LVEDV) and LV ejection fraction (LVEF). Native T1 relaxation time and the extracellular volume fraction (ECV) were utilised as markers of left ventricular (LV) diffuse myocardial fibrosis and late gadolinium enhancement (LGE) was utilised as a marker of LV replacement fibrosis. FRDA genetic severity was assessed using the shorter FXN GAA repeat length (GAA1). RESULTS: There were 93 subjects with FRDA (63 adults, 30 children, 54% males), 9 of whom had a reduced LVEF (<55%). A LVEDV below the normal range was present in 39%, a LVM above the normal range in 22%, and an increased LVM/LVEDV ratio in 89% subjects. In adults with a normal LVEF, there was an independent positive correlation of LVM with GAA1, and a negative correlation with age, but no similar relationships were seen in children. GAA1 was positively correlated with native T1 time in both adults and children, and with ECV in adults, all these associations independent of LVM and LVEDV. LGE was present in 21% of subjects, including both adults and children, and subjects with and without a reduced LVEF. None of GAA1, LVM or LVEDV were predictors of LGE. CONCLUSION: An association between diffuse interstitial LV myocardial fibrosis and genetic severity in FRDA was present independently of FRDA-related LV structural changes. Localised replacement fibrosis was found in a minority of subjects with FRDA and was not associated with LV structural change or FRDA genetic severity in subjects with a normal LVEF.

Perioperative management and outcomes for posterior spinal fusion in patients with Friedreich ataxia: A single-center, retrospective study.

BACKGROUND: Friedreich ataxia is a rare genetic disorder associated with progressive mitochondrial dysfunction leading to widespread sequelae including ataxia, muscle weakness, hypertrophic cardiomyopathy, diabetes mellitus, and neuromuscular scoliosis. Children with Friedreich ataxia are at high risk for periprocedural complications during posterior spinal fusion due to their comorbidities. AIM: To describe our single-center perioperative management of patients with Friedreich ataxia undergoing posterior spinal fusion. METHODS: Adolescent patients with Friedreich ataxia presenting for spinal deformity surgery between 2007 and 2023 were included in this retrospective case series performed at the Children's Hospital of Philadelphia. Perioperative outcomes were reviewed along with preoperative characteristics, intraoperative anesthetic management, and postoperative medical management. RESULTS: Seventeen patients were included in the final analysis. The mean age was 15 ± 2 years old and 47% were female. Preoperatively, 35% were wheelchair dependent, 100% had mild-to-moderate hypertrophic cardiomyopathy with preserved systolic function and no left ventricular outflow tract obstruction, 29% were on cardiac medications, and 29% were on pain medications. Intraoperatively, 53% had transesophageal echocardiography monitoring; 12% had changes in volume status on echo but no changes in function. Numerous combinations of total intravenous anesthetic agents were used, most commonly propofol, remifentanil, and ketamine. Baseline neuromonitoring signals were poor in four patients and one patient lost signals, resulting in 4 (24%) wake-up tests. The majority (75%) were extubated in the operating room. Postoperative complications were high (88%) and ranged from minor complications like nausea/vomiting (18%) to major complications like hypotension/tachycardia (29%) and need for extracorporeal membrane oxygenation support in one patient (6%). CONCLUSIONS: Patients with Friedreich ataxia are at high risk for perioperative complications when undergoing posterior spinal fusion and coordinated multidisciplinary care is required at each stage. Future research should focus on the utility of intraoperative echocardiography, optimal anesthetic agent selection, and targeted fluid management to reduce postoperative cardiac complications.

Programmatic Palliative Care Consultations in Pediatric Heart Transplant Evaluations.

Guidelines advocate for integrating palliative care into the management of heart failure (HF) and of children with life-limiting disease. The potential impact of palliative care integration into pediatric HF on patient-centered outcomes is poorly understood. The present study sought to assess the association of programmatic implementation of palliative care into the heart transplant evaluation process with hospital-free days (HFD) and end of life (EOL) treatment choices. The study included patients less than 19 years of age who underwent a heart transplant evaluation between February 2012 and April 2020 at a single center. Patients evaluated in the programmatic palliative care (PPC) era (January 2016-April 2020) were compared to patients evaluated in the pre-PPC era (February 2012-December 2015). The study included 188 patients, with 91 (48%) in the PPC era and 97 (52%) in the pre-PCC era. Children < 1 year of age at the time of the evaluation represented 32% of the cohort. 52% of patients had single ventricle physiology. PPC was not significantly associated with increased HFD (IRR 0.94 [95% CI 0.79-1.2]). PPC was however associated with intensity of EOL care with decreased mechanical ventilation (OR 0.12 [95% CI 0.02-0.789], p = 0.03) and decreased use of ionotropic support (OR 0.13 [95% CI 0.02-0.85], p =0.03). PPC in pediatric heart transplant evaluations may be associated with less invasive interventions at EOL.

Cardiopulmonary exercise testing on adaptive equipment in children and adults with Friedreich ataxia.

INTRODUCTION/AIMS: Traditional exercise is often difficult for individuals with Friedreich ataxia (FRDA), and evidence is limited regarding how to measure exercise performance in this population. We evaluated the feasibility, reliability, and natural history of adaptive cardiopulmonary exercise test (CPET) performance in children and adults with FRDA. METHODS: Participants underwent CPET on either an arm cycle ergometer (ACE) or recumbent leg cycle ergometer (RLCE) at up to four visits (baseline, 2 weeks, 4 weeks, and 1 year). Maximum work, oxygen consumption (peak VO2), oxygen (O2) pulse, and anaerobic threshold (AT) were measured in those who reached maximal volition. Test-retest reliability was assessed with intraclass coefficients, and longitudinal change was assessed using regression analysis. RESULTS: In our cohort (N = 23), median age was 18 years (interquartile range [IQR], 14-23), median age of FRDA onset was 8 years (IQR 6-13), median Friedreich Ataxia Rating Scale score was 58 (IQR 54-62), and GAA repeat length on the shorter FXN allele (GAA1) was 766 (IQR, 650-900). Twenty-one (91%) completed a maximal CPET (n = 8, ACE and n = 13, RLCE). Age, sex, and GAA1 repeat length were each associated with peak VO2. Preliminary estimates demonstrated reasonable agreement between visits 2 and 3 for peak work by both ACE and RLCE, and for peak VO2, O2 pulse, and AT by RLCE. We did not detect significant performance changes over 1 year. DISCUSSION: Adaptive CPET is feasible in FRDA, a relevant clinical trial outcome for interventions that impact exercise performance and will increase access to participation as well as generalizability of findings.

Characterization of Cardiac-Onset Initial Presentation in Friedreich Ataxia.

We examined the clinical features of Friedreich ataxia (FRDA) patients who present first with cardiac disease in order to understand the earliest features of the diagnostic journey in FRDA. We identified a group of subjects in the FACOMS natural history study whose first identified clinical feature was cardiac. Only 0.5% of the total cohort belonged to this group, which was younger on average at the time of presentation. Their cardiac symptoms ranged from asymptomatic features to heart failure with severe systolic dysfunction. Two of those individuals with severe dysfunction proceeded to heart transplantation, but others spontaneously recovered. In most cases, diagnosis of FRDA was not made until well after cardiac presentation. The present study shows that some FRDA patients present based on cardiac features, suggesting that earlier identification of FRDA might occur through enhancing awareness of FRDA among pediatric cardiologists who see such patients. This is important in the context of newly identified therapies for FRDA.

Multicenter Study of Survival Benefit of Cardiac Resynchronization Therapy in Pediatric and Congenital Heart Disease.

BACKGROUND: Evidence for the efficacy of cardiac resynchronization therapy (CRT) in pediatric and congenital heart disease (CHD) has been limited to surrogate outcomes. OBJECTIVES: This study aimed to assess the impact of CRT upon the risk of transplantation or death in a retrospective, high-risk, controlled cohort at 5 quaternary referral centers. METHODS: Both CRT patients and control patients were <21 years of age or had CHD; had systemic ventricular ejection fraction <45%; symptomatic heart failure; and significant electrical dyssynchrony (QRS duration z score >3 or single-site ventricular pacing >40%) at enrollment. Patients with CRT were matched with control patients via 1:1 propensity score matching. CRT patients were enrolled at CRT implantation; control patients were enrolled at the outpatient clinical encounter where inclusion criteria were first met. The primary endpoint was transplantation or death. RESULTS: In total, 324 control patients and 167 CRT recipients were identified. Mean follow-up was 4.2 ± 3.7 years. Upon propensity score matching, 139 closely matched pairs were identified (20 baseline indices). Of the 139 matched pairs, 52 (37.0%) control patients and 31 (22.0%) CRT recipients reached the primary endpoint. On both unadjusted and multivariable Cox regression analysis, the risk reduction associated with CRT for the primary endpoint was significant (HR: 0.40; 95% CI: 0.25-0.64; P < 0.001; and HR: 0.44; 95% CI: 0.28-0.71; P = 0.001, respectively). On longitudinal assessment, the CRT group had significantly improved systemic ventricular ejection fraction (P < 0.001) and shorter QRS duration (P = 0.015), sustained to 5 years. CONCLUSIONS: In pediatric and CHD patients with symptomatic systolic heart failure and electrical dyssynchrony, CRT was associated with improved heart transplantation-free survival.

Research Gaps in Pediatric Heart Failure: Defining the Gaps and Then Closing Them Over the Next Decade.

Given the numerous opportunities and the wide knowledge gaps in pediatric heart failure, an international group of pediatric heart failure experts with diverse backgrounds were invited and tasked with identifying research gaps in each pediatric heart failure domain that scientists and funding agencies need to focus on over the next decade.

Hypertension: An Important But Reversible Cause of Systolic Dysfunction in a Cohort of Pediatric Patients.

Cardiac dysfunction due to hypertension (CDHTN) in pediatrics is not well described. We aimed to describe the presentation and outcomes of pediatric CDHTN and identify clinical features associated with resolution of dysfunction. A single-center retrospective cohort study of patients ≤ 21 years with CDHTN from January 2005-September 2020 was performed. Patients with systolic dysfunction without another cause, blood pressure > 95th percentile, and physician judgment that dysfunction was secondary to hypertension were included. Demographics, clinical characteristics, echocardiographic findings, and outcomes were examined using Fisher's exact and Mann-Whitney U tests. Multiple correspondence analysis was used to explore the relationship of resolution of dysfunction to clinical features. Thirty-four patients were analyzed at a median age of 10.9 (IQR 0.3-16.9) years. Patients were divided into groups < 1 year (n = 12) and ≥ 1 year (n = 22). Causes of hypertension were varied by age, with renovascular disease most common in infants (42%) and medical renal disease most common in older patients (77%). Echocardiography demonstrated mild LV dilation (median LV end-diastolic z-score 2.6) and mild LV hypertrophy (median LV mass z-score 2.4). Most patients (81%) had resolution of dysfunction, particularly infants (92%). One patient died and one patient was listed for heart transplant. None required mechanical circulatory support (MCS). No clinical features were statistically associated with resolution of dysfunction. Hypertension is an important but reversible cause of systolic dysfunction in children. Patients are likely to recover with low mortality and low utilization of MCS or transplantation. Further studies are needed to confirm features associated with resolution of dysfunction.

Diagnostic Yield of Exome Sequencing in Pediatric Cardiomyopathy.

OBJECTIVE: To assess the diagnostic yield of exome sequencing (ES) in pediatric cardiomyopathy. STUDY DESIGN: A single-institution, retrospective chart review of 91 patients with pediatric cardiomyopathy was performed. While pediatric cardiomyopathy is often genetic in nature, no genetic test is recommended as standard of care. All our patients were diagnosed with cardiomyopathy and evaluated by a medical geneticist between January 2010 through September 2022. Demographic information and clinical data were abstracted. RESULTS: Of 91 patients with pediatric cardiomyopathy, 36 (39.6%) received a diagnosis by ES. Twenty-two (61.1%) of these diagnoses would have been missed on cardiac multigene panel testing. The diagnostic yield for cardiomyopathy presenting under 1 year of age was 38.3%, while the yield for patients over 1 year of age was 41.9%. CONCLUSIONS: ES has a high diagnostic yield in pediatric cardiomyopathy compared with a gene panel. Over 60% of patients with diagnosis by ES would not have received their molecular genetic diagnosis if only multigene panel testing was sent. Diagnostic yield did not vary significantly between the subtypes of cardiomyopathy and patient age groups, highlighting the likely clinical utility of ES for all pediatric cardiomyopathy patients.

Three decades of collaboration through the Pediatric Heart Transplant Society Registry: A journey through registry data with a highlight on children with single ventricle anatomy.

BACKGROUND: The Pediatric Heart Transplant Society (PHTS) Registry was founded 30 years ago as a collaborative effort among like-minded providers of this novel life-saving technique for children with end-stage heart failure. In the intervening decades, the data from the Registry have provided invaluable knowledge to the field of pediatric heart transplantation. This report of the PHTS Registry provides a comprehensive look at the data, highlighting both the longevity of the registry and one unique aspect of the PHTS registry, allowing for exploration into children with single ventricle anatomy. METHODS: The PHTS database was queried from January 1, 1993 to December 31, 2019 to include pediatric (age < 18 years) patients listed for HT. For our analysis, we primarily analyzed patients by era. The early era was defined as children listed for HT from January 1, 1993 to December 31, 2004; middle era January 1, 2005 to December 31, 2009; and recent era January 1, 2010 to December 31, 2019. Outcomes after listing and transplant, including mortality and morbidities, are presented as unadjusted for risk, but compared across eras. RESULTS: Since 1993, 11 995 children were listed for heart transplant and entered into the PHTS Registry with 9755 listed during the study period. The majority of listings occurred within the most recent era. Waitlist survival improved over the decades as did posttransplant survival. Other notable changes over time include fewer patients experiencing allograft rejection or infection after transplant. Waitlist and posttransplant survival have changed dramatically in patients with single ventricle physiology and significantly differ by stage of single ventricle palliation. SUMMARY: Key points from this PHTS Registry summary and focus on patients with single ventricle congenital heart disease in particular, include the changing landscape of candidates and recipients awaiting heart transplant. There is clear improvement in waitlist and transplant outcomes for children with both cardiomyopathy and congenital heart disease alike.

Deep Learning Algorithm Detects Presence of Disorganization of Retinal Inner Layers (DRIL)-An Early Imaging Biomarker in Diabetic Retinopathy.

Purpose: To develop and train a deep learning-based algorithm for detecting disorganization of retinal inner layers (DRIL) on optical coherence tomography (OCT) to screen a cohort of patients with diabetic retinopathy (DR). Methods: In this cross-sectional study, subjects over age 18, with ICD-9/10 diagnoses of type 2 diabetes with and without retinopathy and Cirrus HD-OCT imaging performed between January 2009 to September 2019 were included in this study. After inclusion and exclusion criteria were applied, a final total of 664 patients (5992 B-scans from 1201 eyes) were included for analysis. Five-line horizontal raster scans from Cirrus HD-OCT were obtained from the shared electronic health record. Two trained graders evaluated scans for presence of DRIL. A third physician grader arbitrated any disagreements. Of 5992 B-scans analyzed, 1397 scans (∼30%) demonstrated presence of DRIL. Graded scans were used to label training data for the convolution neural network (CNN) development and training. Results: On a single CPU system, the best performing CNN training took ∼35 mins. Labeled data were divided 90:10 for internal training/validation and external testing purpose. With this training, our deep learning network was able to predict the presence of DRIL in new OCT scans with a high accuracy of 88.3%, specificity of 90.0%, sensitivity of 82.9%, and Matthews correlation coefficient of 0.7. Conclusions: The present study demonstrates that a deep learning-based OCT classification algorithm can be used for rapid automated identification of DRIL. This developed tool can assist in screening for DRIL in both research and clinical decision-making settings. Translational Relevance: A deep learning algorithm can detect disorganization of retinal inner layers in OCT scans.

Temporal trends in primary payers in pediatric heart transplant and association with long-term survival.

BACKGROUND: Pediatric heart transplantation (HT) is resource intensive. In adults, there has been an increase in the proportion of HTs funded by public insurance, with post-HT outcomes inferior to those funded by private sources. Trends in the funding of pediatric HT and outcomes in children have not been described. METHODS: We queried the United Network for Organ Sharing (UNOS) database for children (<18 years) listed for and undergoing HT between 2004 and 2021. We identified the primary payer at listing, HT, 1 year, and 1-5 years following HT. Trends were analyzed using generalized logit models. Multivariable-extended Cox regression models were used to test the relationship between insurance type at the time of transplant and time to death or re-transplant. RESULTS: There were 6382 pediatric patients who underwent transplants and had either public or private insurance at the time of transplant. The percentage of patients with public insurance at the time of HT increased over time. Public insurance at the time of HT was associated with an increased risk of death or re-transplant beyond 2 months after HT (adjusted HR at 6 months = 1.43, 95% CI: 1.13-1.81, p = .003; adjusted HR at 9 months = 1.67, 95% CI: 1.17-2.37, p = .004). CONCLUSION: There has been a statistically significant trend toward increasing public insurance for children awaiting, at the time of, and after HT. Black patients and those with public insurance at HT have worse long-term outcomes. This study highlights ongoing disparities in pediatric HT and the need to focus efforts on achieving equitable outcomes.

Cost-effectiveness of bivalirudin in pediatric ventricular assist devices.

BACKGROUND: Despite recent data suggesting improved outcomes with bivalirudin vs heparin in pediatric Ventricular assist devices (VAD), higher costs remain a barrier. This study quantified trends in bivalirudin use and compared outcomes, resource utilization, and cost-effectiveness associated with bivalirudin vs heparin. METHODS: Children age 0 to 6 year who received VAD from 2009 to 2021 were identified in Pediatric Health Information System. Bivalirudin use was evaluated using trend analysis and outcomes were compared using Fine-Gray subdistrubtion hazard ratios (SHR). Daily-level hospital costs were compared due to differences in length of stay. Cost-effectiveness was evaluated using incremental cost-effectiveness ratio (ICER). RESULTS: Of 691 pediatric VAD recipients (median age 1 year, IQR 0-2), 304 (44%) received bivalirudin with 90% receiving bivalirudin in 2021 (trend p-value <0.01). Bivalirudin had lower hospital mortality (26% vs 32%; adjusted SHR 0.57, 95% CI 0.40-0.83) driven by lower VAD mortality (20% vs 27%; adjusted SHR 0.46, 95% CI 0.32-0.77) after adjusting for year, age, diagnosis, and center VAD volume. Post-VAD length of stay was longer for bivalirudin than heparin (median 91 vs 64 days, respectively, p < 0.001). Median daily-level costs were lower among bivalirudin (cost ratio 0.87, 95% CI 0.79-0.96) with higher pharmacy costs offset by lower imaging, laboratory, supply, and room/board costs. Estimated ICER for bivalirudin vs heparin was $61,192 per quality-adjusted life year gained with a range of $27,673 to $131,243. CONCLUSIONS: Bivalirudin use significantly increased over the past decade and is now used in 90% young pediatric VAD recipients. Bivalirudin was associated with significantly lower hospital mortality and an ICER <$65,000, making it a cost-effective therapy for pediatric VAD recipients.

Word imageability is associated with expressive vocabulary in children with autism spectrum disorder.

Background & aims: Throughout typical development, children prioritize different perceptual, social, and linguistic cues to learn words. The earliest acquired words are often those that are perceptually salient and highly imageable. Imageability, the ease in which a word evokes a mental image, is a strong predictor for word age of acquisition in typically developing (TD) children, independent of other lexicosemantic features such as word frequency. However, little is known about the effects of imageability in children with autism spectrum disorder (ASD), who tend to have differences in linguistic processing and delayed language acquisition compared to their TD peers. This study explores the extent to which imageability and word frequency are associated with early noun and verb acquisition in children with ASD. Methods: Secondary analyses were conducted on previously collected data of 156 children (78 TD, 78 ASD) matched on sex and parent-reported language level. Total expressive vocabulary, as measured by the MacArthur Bates Communicative Development Inventory (MB-CDI), included 123 words (78 nouns, 45 verbs) that overlapped with previously published imageability ratings and word input frequencies. A two-step hierarchical linear regression was used to examine the relationship between word input frequency, imageability, and total expressive vocabulary. An F-test was then used to assess the unique contribution of imageability on total expressive vocabulary when controlling for word input frequency. Results: In both the TD and ASD groups, imageability uniquely explained a portion of the variance in total expressive vocabulary size, independent of word input frequency. Notably, imageability was significantly associated with noun vocabulary and verb vocabulary size alone, with imageability explaining a greater portion of the variance in total nouns produced than in total verbs produced. Conclusions: Imageability was identified as a significant lexicosemantic feature for describing expressive vocabulary size in children with ASD. Consistent with literature on TD children, children with ASD who have small vocabularies primarily produce words that are highly imageable. Children who are more proficient word learners with larger vocabularies produce words that are less imageable, indicating a potential shift away from reliance on perceptual-based language processing. This was consistent across both noun and verb vocabularies. Implications: Our findings contribute to a growing body of literature describing early word learning in children with ASD and provide a basis for exploring the use of multisensory language learning strategies.

Arrhythmias in Repaired Tetralogy of Fallot: A Scientific Statement From the American Heart Association.

Arrhythmia and sudden cardiac death remain common in repaired tetralogy of Fallot and affect even those with excellent anatomic repairs. Atrial arrhythmia often has mechanisms different from those in acquired heart disease. Ventricular arrhythmia remains a major source of mortality in repaired tetralogy of Fallot. Noninvasive risk stratification is important to identify patients who may benefit from ablation or primary prevention implantable cardioverter defibrillators. Multiple noninvasive risk factors are associated with ventricular arrhythmia, but no universally accepted risk stratification algorithm exists. The mechanism of ventricular arrhythmia is usually attributable to a consistent and discrete set of slowly conducting anatomic isthmuses related to both the native anatomy and the consequences of the surgical repair, which interact with ventricular remodeling to provide arrhythmic substrate. This substrate can be identified during electroanatomic mapping and prophylactically ablated in appropriate patients. This scientific statement discusses the mechanisms and treatment of arrhythmia in repaired tetralogy of Fallot.