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.

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.

Emergency Department Use and Hospital Mortality Among Heart Transplant Recipients in the United States.

BACKGROUND: Annual heart transplant (HT) volumes have increased, as have post-HT outpatient care needs. Data on HT-related emergency department (ED) visits are limited. METHODS AND RESULTS: A retrospective analysis of 177 450 HT patient ED visits from the 2009 to 2018 Nationwide Emergency Department Sample was conducted. HT recipients, primary diagnoses, and comorbidities associated with ED visits were identified via International Classification of Diseases, Ninth Revision (ICD-9) and International Classification of Diseases, Tenth Revision (ICD-10) codes. Multivariable logistic regression was used to predict outcomes of hospital admission and death. HT volumes and HT-related ED visits increased from 2009 to 2018. Infection was the most common primary diagnosis (24%), and cardiac primary diagnoses represented 10% of encounters. Hospital admissions occurred in 48% of visits, but overall mortality was low (1.6%). Length of stay was 3.1 days (interquartile range, 1.6-5.9 days), and comorbidity burden was high: 42% had hypertension, 38% had diabetes, and 31% had ≥2 comorbidities. Those aged ≥65 years had significantly higher odds of admission (odds ratio [OR], 2.14 [95% CI, 1.97-2.33]) and death (OR, 2.06 [95% CI, 1.61-2.62]). Comorbidities increased odds of admission (OR, 1.62 [95% CI, 1.51-1.75]) but not death. Renal primary diagnosis had the highest risk of admission (OR, 4.1 [95% CI, 3.6-4.6]), but cardiac primary diagnosis had the highest odds of death (OR, 11.6 [95% CI, 9.1-14.8]). CONCLUSIONS: HT-related ED visits increased from 2009 to 2018 with high admission rates but low in-hospital mortality, suggesting an opportunity to improve prehospital care. Older patients and those with cardiac primary diagnoses had the highest risk of death. The observed contrast between predictors of admission and mortality signals a need for further study to improve risk stratification and outpatient care strategies.

School age and adolescent heart failure following the Norwood procedure.

BACKGROUND: Heart failure results in significant morbidity and mortality for young children with hypoplastic left heart syndrome (HLHS) following the Norwood procedure. The trajectory in later childhood is not well described. METHODS: We studied the outcome into adolescence of participants enrolled in the Single Ventricle Reconstruction trial who underwent the Fontan procedure or survived to 6 years without having undergone Fontan procedure. The primary outcome was heart failure events, defined as heart transplant listing or death attributable to heart failure. Symptomatic heart failure for participants surviving 10 or more years was also assessed utilizing the Pediatric Quality of Life Inventory (PedsQL). RESULTS: Of the 345 participants who underwent a Fontan operation or survived to 6 years without Fontan, 25 (7.2%) had a heart failure event before the age of 12 years. Among these, 21 were listed for heart transplant, and 4 died from heart failure. Nineteen participants underwent heart transplant, all of whom survived to age 12 years. Factors associated with a heart failure event included longer Norwood hospital length of stay, aortic atresia, and no Fontan operation by age 6 years. Assessment of heart failure symptoms at 12 years of age revealed that 24 (12.2%) of 196 PedsQL respondents "often" or "almost always" had difficulty walking more than one block. CONCLUSIONS: Heart failure events occur in over 5% of children with palliated HLHS between preschool age and adolescence. Outcomes for children listed for transplant are excellent. However, a substantial portion of palliated HLHS children have significant symptoms of heart failure at 12 years of age.

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.

Introduction of transcatheter edge-to-edge repair in patients with congenital heart disease at a children's hospital.

BACKGROUND: Atrioventricular valve regurgitation (AVVR) is a devastating complication in children and young adults with congenital heart disease (CHD), particularly in patients with single ventricle physiology. Transcatheter edge-to-edge repair (TEER) is a rapidly expanding, minimally invasive option for the treatment of AVVR in adults that avoids the morbidity and mortality associated with open heart surgery. However, application of TEER in in CHD and in children is quite novel. We describe the development of a peri-procedural protocol including image-derived pre-intervention simulation, with successful application to four patients. AIMS: To describe the initial experience using the MitraClip system for TEER of dysfunctional systemic atrioventricular valves in patients with congential heart disease within a pediatric hospital. METHODS: A standardized screening and planning process was developed using cardiac magnetic resonance imaging, three dimensional echocardiography and both virtual and physical simulation. Procedures were performed using the MitraClip G4 system and patients were clinically followed post-intervention. RESULTS: A series of four CHD patients with at least severe AVVR were screened for suitability for TEER with the MitraClip system: three patients had single ventricle physiology and Fontan palliation, and one had repair of a common atrioventricular canal defect. Each patient had at least severe systemic AVVR and was considered at prohibitively high risk for surgical repair. Each patient underwent a standardized preprocedural screening protocol and image-derived modeling followed by the TEER procedure with successful clip placement at the intended location in all cases. CONCLUSIONS: The early results of our protocolized efforts to introduce TEER repair of severe AV valve regurgitation with MitraClip into the CHD population within our institution are encouraging. Further investigations of the use of TEER in this challenging population are warranted.

The Effect of Udenafil on Heart Rate and Blood Pressure in Adolescents With the Fontan Circulation.

The Fontan Udenafil Exercise Longitudinal (FUEL) trial showed that treatment with udenafil was associated with improved exercise performance at the ventilatory anaerobic threshold in children with Fontan physiology. However, it is not known how the initiation of phosphodiesterase 5 inhibitor therapy affects heart rate and blood pressure in this population. These data may help inform patient selection and monitoring after the initiation of udenafil therapy. The purpose of this study is to evaluate the effects of udenafil on vital signs in the cohort of patients enrolled in the FUEL trial. This international, multicenter, randomized, double-blind, placebo-controlled trial of udenafil included adolescents with single ventricle congenital heart disease who had undergone Fontan palliation. Changes in vital signs (heart rate [HR], systolic [SBP] and diastolic blood pressure [DBP]) were compared both to subject baseline and between the treatment and the placebo groups. Additional exploratory analyses were performed to evaluate changes in vital signs for prespecified subpopulations believed to be most sensitive to udenafil initiation. Baseline characteristics were similar between the treatment and placebo cohorts (n = 200 for each). The groups demonstrated a decrease in HR, SBP, and DBP 2 hours after drug/placebo administration, except SBP in the placebo group. There was an increase in SBP from baseline to after 6-min walk test in the treatment and placebo groups, and the treatment group showed an increase in HR (87.4 ± 15.0 to 93.1 ± 19.4 beats/min, p <0.01) after exercise. When comparing changes from baseline to the 26-week study visit, small decreases in both SBP (-1.9 ± 12.3 mm Hg, p = 0.03) and DBP (-3.0 ± 9.6 mm Hg, p <0.01) were seen in the treatment group. There were no clinically significant differences between treatment and placebo group in change in HR or blood pressure in the youngest age quartile, lightest weight quartile, or those on afterload-reducing agents. In conclusion, initiation of treatment with udenafil in patients with Fontan circulation was not associated with clinically significant changes in vital signs, implying that for patients similar to those enrolled in the FUEL trial, udenafil can be started without the requirement for additional monitoring after initial administration.

Reduced incidence of cardiac rejection in multi-organ transplants: A propensity matched study.

BACKGROUND: Rejection remains a primary cause of graft loss after heart transplant (HT). Recognizing the immunomodulation of multi-organ transplant can enhance our understanding of the mechanisms of cardiac rejection. METHODS: This retrospective cohort study identified patients from the UNOS database with isolated heart (H, N = 37 433), heart-kidney (HKi, N = 1516), heart-liver (HLi, N = 286), and heart-lung (HLu, N = 408) transplants from 2004 to 2019. Propensity score matching reduced baseline differences between groups. Outcomes included risk of rejection prior to transplant hospital discharge and within 1 year, and mortality within 1 year of transplant. RESULTS: In the propensity score matched data, the relative risk of being treated for rejection prior to transplant hospital discharge was 61% lower for HKi (RR .39, 95% CI .29, .53) and 87% lower for HLi (RR .13, 95% CI .05, .37) compared to H. Similarly, the probability of being treated for rejection in the first year after transplant remained lower in HKi (RR .45, 95% CI .35, .57) and HLi (RR .13, 95% CI .06, .28) compared to H. The 1-year survival analysis revealed an equivalent risk of death in HKi (HR .84, 95% CI .68, 1.03) and HLi (HR 1.41, 95% CI .83, 2.41) compared to H, while HLu had a higher risk of death in the first year after transplant (HR 1.65, 95% CI 1.17, 2.33). CONCLUSIONS: Recipients of HKi and HLi experience a reduced risk of rejection when compared to H, but an equivalent risk of 1 yr mortality. These findings have important implications for the future of HT medicine.

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.

Association of Donors With US Public Health Service Risk Criteria and Outcomes After Adult vs Pediatric Cardiac Transplant.

Importance: The United Network for Organ Sharing (UNOS) evaluates donor risk for acute transmission of HIV, hepatitis B, or hepatitis C based on US Public Health Services (PHS)-specific criteria. However, recent data regarding use and outcomes of those donors with PHS risk criteria among pediatric and adult heart transplant recipients are lacking. Objective: To compare use and outcomes of graft from donors with PHS risk criteria vs those with a standard-risk donor (SRD) in children vs adults in a contemporary cohort. Design, Setting, and Participants: This cohort was a nationwide analysis of heart transplants in the US that used data from the UNOS database. Participants were children (<18 years old) and adults (≥18 years old) who received a heart transplant from January 1, 2010, to December 31, 2021. Exposures: UNOS-defined donor risk status. Main Outcomes and Measures: Trend analysis compared changes in PHS risk criteria use among children and adults. Patient survival was analyzed using Kaplan-Meier curves with log rank and Cox proportional hazards to compare PHS risk-criteria outcomes vs SRD-criteria outcomes in children and adult heart transplant recipients. Additional analysis was performed among adults who received a PHS-risk criteria graft that was previously declined for pediatric recipients. Results: Of 5115 pediatric transplant recipients (donor without PHS risk median [IQR] age, 5 [0-13] years and donor with PHS risk median [IQR] age, 8 [0-14] years) and 30 289 adult heart transplant recipients (donor without PHS risk median [IQR] age, 56 [46-63] years and donor with PHS risk median [IQR] age, 57 [47-63] years), PHS risk criteria comprised 8% in children vs 25% in adults. PHS criteria are being increasingly used over the past decade with the proportion of recipients transplanted with PHS risk-criteria donors being approximately 3 times greater among adult recipients than children recipients. Pediatric recipients of a PHS risk-criteria donor had greater pretransplant ventilatory support, whereas adult recipients of a PHS risk-criteria donor had greater pretransplant extracorporeal membrane oxygenation use. Patient survival was similar between pediatric recipients of PHS risk-criteria grafts vs SRD-criteria grafts and slightly higher among adult recipients of PHS risk-criteria grafts vs SRD-criteria grafts. The 1778 adult recipients who received a PHS criteria-risk donor that was previously declined for pediatric recipients had similar patient survival recipients compared with SRD-criteria donors (HR, 0.92; 95% CI, 0.81-1.03; P = .18). Conclusions and Relevance: In the current era, a 3-fold greater proportion of adult recipients receive a PHS risk-criteria graft compared with children despite similar posttransplant patient survival. The ongoing organ donor shortage underscores the need for consideration of PHS risk criteria where these donors remain underused.

Sex Differences in Left Ventricular Assist Device-related Emergency Department Encounters in the United States.

BACKGROUND: There is a paucity of data regarding sex differences in the profiles and outcomes of ambulatory patients on left ventricular assist device (LVAD) support who present to the emergency department (ED). METHODS AND RESULTS: We performed a retrospective analysis of 57,200 LVAD-related ED patient encounters from the 2010 to 2018 Nationwide Emergency Department Sample. International Classification of Diseases Clinical Modification, Ninth Revision and Tenth Revision, codes identified patients aged 18 years or older with LVADs and associated primary and comorbidity diagnoses. Clinical characteristics and outcomes were stratified by sex and compared. Multivariable logistic regression was used to evaluate predictors of hospital admission and death. Female patient encounters comprised 27.2% of ED visits and occurred at younger ages and more frequently with obesity and depression (all P < .01). There were no sex differences in presentation for device complication, stroke, infection, or heart failure (all P > .05); however, female patient encounters were more often respiratory- and genitourinary or gynecological related (both P < .01). After adjustment for age group, diabetes, depression, and hypertension, male patient encounters had a 38% increased odds of hospital admission (95% confidence interval 1.20-1.58), but there was no sex difference in the adjusted odds of death (odds ratio 1.11, 95% confidence interval 0.86-1.45). CONCLUSIONS: Patient encounters of females on LVAD support have significantly different comorbidities and outcomes compared with males. Further inquiry into these sex differences is imperative to improve long-term outcomes.

Health Care Use of Cardiac Specialty Care in Children With Muscular Dystrophy in the United States.

Background Duchenne and Becker muscular dystrophy are progressive disorders associated with cardiac mortality. Guidelines recommend routine surveillance; we assess cardiac resource use and identify gaps in care delivery. Methods and Results Male patients, aged 1 to 18 years, with Duchenne and Becker muscular dystrophy between January 2013 and December 2017 were identified in the IBM MarketScan Research Database. The cohort was divided into <10 and 10 to 18 years of age. The primary outcome was rate of annual health care resource per person year. Resource use was assessed for place of service, cardiac testing, and medications. Adjusted incidence rate ratios (IRRs) were estimated using a Poisson regression model. Medication use was measured by proportion of days covered. There were 1386 patients with a median follow-up time of 3.0 years (interquartile range, 1.9-4.7 years). Patients in the 10 to 18 years group had only 0.40 (95% CI, 0.35-0.45) cardiology visits per person year and 0.66 (95% CI, 0.62-0.70) echocardiography/magnetic resonance imaging per person year. Older patients had higher rates of inpatient admissions (IRR, 1.46; 95% CI, 1.03-2.09), outpatient cardiology visits (IRR, 2.0; 95% CI, 1.66-2.40), cardiac imaging (IRR, 1.59; 95% CI, 1.40-1.80), and Holter monitoring (IRR, 3.33; 95% CI, 2.35-4.73). A proportion of days covered >80% for angiotensin-converting enzyme inhibitors/angiotensin receptor blockers was observed in 13.6% (419/3083) of total person years among patients in the 10 to 18 years group. Conclusions Children 10 to 18 years of age have higher rates of cardiac resource use compared with those <10 years of age. However, rates in both age groups fall short of guidelines. Opportunities exist to identify barriers to resource use and optimize cardiac care for patients with Duchenne and Becker muscular dystrophy.

Safety and Feasibility of Exercise Rehabilitation in Children with Ventricular Assist Devices.

Children with advanced heart failure may require ventricular assist devices (VAD) while awaiting heart transplantation. Currently, no data exist regarding the safety of exercise rehabilitation (ER) in children on VAD support. The purpose of this study was to determine the safety and feasibility of ER in children on VAD support awaiting heart transplantation. Eligible patients underwent VAD placement between 1998 and 2019; both inpatient and outpatient participants were included. After VAD implantation and when ambulatory, patients were enrolled in ER. Exercise sessions were scheduled three times a week and consisted of aerobic and musculoskeletal conditioning. A total of 29 patients (59% male, mean age 14 ± 3.2 years) were included with a median VAD duration of 120 ± 109 days. Cardiac diagnoses included cardiomyopathy (81%) and congenital heart disease (19%). VAD type included pulsatile (59%) and continuous-flow devices (41%). Eight hundred and sixty-four (85%) ER sessions were successfully completed and began at a mean of 49 days (range 19-108) after VAD implant. No adverse events, including episodes of hypotension, significant complex arrhythmia, or VAD malfunction occurred during exercise testing or ER, and no sessions were discontinued prematurely. Pediatric patients on VAD support can safely participate in ER with relatively high compliance, and sessions can be implemented early after VAD implantation. Given the safety profile, ER in pediatric VAD recipients, which is a modifiable pre-transplant risk factor that may improve functional capacity, warrants further study as a potential modality to improve post-transplant outcomes.

Novel Risk Model to Predict Emergency Department Associated Mortality for Patients Supported With a Ventricular Assist Device: The Emergency Department-Ventricular Assist Device Risk Score.

Background The past decade has seen tremendous growth in patients with ambulatory ventricular assist devices. We sought to identify patients that present to the emergency department (ED) at the highest risk of death. Methods and Results This retrospective analysis of ED encounters from the Nationwide Emergency Department Sample includes 2010 to 2017. Using a random sampling of patient encounters, 80% were assigned to development and 20% to validation cohorts. A risk model was derived from independent predictors of mortality. Each patient encounter was assigned to 1 of 3 groups based on risk score. A total of 44 042 ED ventricular assist device patient encounters were included. The majority of patients were male (73.6%), <65 years old (60.1%), and 29% presented with bleeding, stroke, or device complication. Independent predictors of mortality during the ED visit or subsequent admission included age ≥65 years (odds ratio [OR], 1.8; 95% CI, 1.3-4.6), primary diagnoses (stroke [OR, 19.4; 95% CI, 13.1-28.8], device complication [OR, 10.1; 95% CI, 6.5-16.7], cardiac [OR, 4.0; 95% CI, 2.7-6.1], infection [OR, 5.8; 95% CI, 3.5-8.9]), and blood transfusion (OR, 2.6; 95% CI, 1.8-4.0), whereas history of hypertension was protective (OR, 0.69; 95% CI, 0.5-0.9). The risk score predicted mortality areas under the curve of 0.78 and 0.71 for development and validation. Encounters in the highest risk score strata had a 16-fold higher mortality compared with the lowest risk group (15.8% versus 1.0%). Conclusions We present a novel risk score and its validation for predicting mortality of patients with ED ventricular assist devices, a high-risk, and growing, population.