A prospective multicenter feasibility study of a miniaturized implantable continuous flow ventricular assist device in smaller children with heart failure.

BACKGROUND: There is no FDA-approved left ventricular assist device (LVAD) for smaller children permitting routine hospital discharge. Smaller children supported with LVADs typically remain hospitalized for months awaiting heart transplant-a major burden for families and a challenge for hospitals. We describe the initial outcomes of the Jarvik 2015, a miniaturized implantable continuous flow LVAD, in the NHLBI-funded Pumps for Kids, Infants, and Neonates (PumpKIN) study, for bridge-to-heart transplant. METHODS: Children weighing 8 to 30 kg with severe systolic heart failure and failing optimal medical therapy were recruited at 7 centers in the United States. Patients with severe right heart failure and single-ventricle congenital heart disease were excluded. The primary feasibility endpoint was survival to 30 days without severe stroke or non-operational device failure. RESULTS: Of 7 children implanted, the median age was 2.2 (range 0.7, 7.1) years, median weight 10 (8.2 to 20.7) kilograms; 86% had dilated cardiomyopathy; 29% were INTERMACS profile 1. The median duration of Jarvik 2015 support was 149 (range 5 to 188) days where all 7 children survived including 5 to heart transplant, 1 to recovery, and 1 to conversion to a paracorporeal device. One patient experienced an ischemic stroke on day 53 of device support in the setting of myocardial recovery. One patient required ECMO support for intractable ventricular arrhythmias and was eventually transplanted from paracorporeal biventricular VAD support. The median pump speed was 1600 RPM with power ranging from 1-4 Watts. The median plasma free hemoglobin was 19, 30, 19 and 30 mg/dL at 7, 30, 90 and 180 days or time of explant, respectively. All patients reached the primary feasibility endpoint. Patient-reported outcomes with the device were favorable with respect to participation in a full range of activities. Due to financial issues with the manufacturer, the study was suspended after consent of the eighth patient. CONCLUSION: The Jarvik 2015 LVAD appears to hold important promise as an implantable continuous flow device for smaller children that may support hospital discharge. The FDA has approved the device to proceed to a 22-subject pivotal trial. Whether this device will survive to commercialization remains unclear because of the financial challenges faced by industry seeking to develop pediatric medical devices. (Supported by NIH/NHLBI HHS Contract N268201200001I, clinicaltrials.gov 02954497).

Impact of a positive crossmatch on pediatric heart transplant outcomes.

BACKGROUND: Pediatric heart transplant (HT) candidates experience high waitlist mortality due to a limited donor pool that is constrained in part by anti-HLA sensitization. We evaluated the impact of CDC and Flow donor-specific crossmatch (XM) results on pediatric HT outcomes. METHODS: All pediatric HTs between 1999 and 2019 in the OPTN database were included. Donor-specific XM results were sub-categorized based on CDC and Flow results. Primary outcomes were treated rejection in the first year and time to death or allograft loss. Propensity scores were utilized to adjust for differences in baseline characteristics. RESULTS: A total of 4,695 pediatric HT patients with T-cell XM data were included. After propensity score adjustment, a positive T-cell CDC-XM was associated with 2 times higher odds of treated rejection (OR 2.29 (1.56, 3.37)) and shorter time to death/allograft loss (HR 1.50 (1.19, 1.88)) compared to a negative Flow-XM. HT recipients who were Flow-XM positive with negative/unknown CDC-XM did not have higher odds of rejection or shorter time to death/allograft loss. An isolated positive B-cell XM was also not associated with worse outcomes. Over the study period XM testing shifted from CDC- to Flow-based assays. CONCLUSIONS: A positive donor-specific T-cell CDC-XM was associated with rejection and death/allograft loss following pediatric HT. This association was not observed with a positive T-cell Flow-XM or B-cell XM result alone. The shift away from performing the CDC-XM may result in loss of important prognostic information unless the clinical relevance of quantitative Flow-XM results on heart transplant outcomes is systematically studied.

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.

Major Adverse Dystrophinopathy Events (MADE) Score as Marker of Cumulative Morbidity and Risk for Mortality in Boys with Duchenne Muscular Dystrophy.

Background: Overlapping symptoms from cardiomyopathy, respiratory insufficiency, and skeletal myopathy confound assessment of heart failure in Duchenne Muscular Dystrophy. We developed an ordinal scale of multiorgan clinical variables that reflect cumulative disease burden-the Major Adverse Dystrophinopathy Event (MADE) Score. We hypothesized that a higher MADE score would be associated with increased mortality in boys with Duchenne Muscular Dystrophy. The Cooperative International Neuromuscular Research Group Duchenne Natural History Study dataset was utilized for validation. Methods: Duchenne Natural History Study variables were selected based on clinical relevance to prespecified domains: Cardiac, Pulmonary, Myopathy, Nutrition. Severity points (0-4) were assigned and summed for study visits. MADE score for cohorts defined by age, ambulatory status, and survival were compared at enrollment and longitudinally.Associations between MADE score and mortality were examined. Results: Duchenne Natural History Study enrolled 440 males, 12.6 ±6.1 years old, with 3,559 visits over 4.6 ±2.8 years, 45 deaths. MADE score increased with age and nonambulatory status. Mean MADE score per visit was 19 ±10 for those who died vs. 9.8 ±9.3 in survivors p=0.03. Baseline MADE score >12 predicted mortality independent of age (78% sensitivity, CPE.70). Rising MADE score trajectory was associated with mortality in models adjusted for enrollment age, follow-up time, and ambulatory status, all p<.001. Conclusion: A multiorgan severity score, MADE, was developed to track cumulative morbidities that impact heart failure in Duchenne muscular dystrophy. MADE score predicted Duchenne Natural History Study mortality. MADE score can be used for serial heart failure assessment in males and may serve as an endpoint for Duchenne muscular dystrophy clinical research.

Supplemental nutrition, feeding disorders, and renourishment in pediatric heart failure through transplantation.

BACKGROUND: Tube feeds are used commonly in children listed for heart transplant; however, rates of renourishment and development of feeding disorders are not sufficiently characterized. METHODS: Retrospective review of pediatric heart transplant recipients from January 1, 2014, to January 3, 2021. Demographics, anthropometric, and nutritional data were collected from heart transplant listing through 3 years post-transplant. Renourishment rates, presence of a feeding disorder, and need for a gastric feeding tube were analyzed. Multivariable analysis was conducted to identify risks for poor nutritional outcomes. RESULTS: Of 104 patients, 35 (34%) and 36 (35%) were malnourished at heart transplant listing and transplant, respectively, persisting in 21/91 (23%) 1 year postheart transplant. Forty (38%) received tube feeds at listing, 42 (40%) at heart transplant, and 18/90 (20%) 1 year post-transplant. Rates of feeding disorders fell from 23% at transplantation to 10% 1 year post-transplant. Feeding disorders were associated with younger age at heart transplant (p < .001) and congenital heart disease (p = .03). Forty-six percent of infants required a gastric feeding tube. Renourishment occurred in 20% during listing and was associated with ventricular assist device support (p = .03) and noncalorically dense feeds (p = .03). Malnutrition at transplant was associated with inferior post-transplant survival (6/36 (17%) vs. 2/68 (3%); p = .02). CONCLUSIONS: Malnourishment requiring tube feeds is common in pediatric heart transplant candidates; however, most patients who eventually survive to transplant remain malnourished at time of transplantation and 1 year later. While some children develop feeding disorders, they generally resolve by 1 year post-transplant.

Functional status predicts pediatric heart transplant outcomes: A united network for organ sharing (UNOS) database study.

BACKGROUND: Functional status predicts waitlist survival in adult heart transplantation and is an independent predictor of outcomes in pediatric liver transplantation. This has not been studied in pediatric heart transplantation. Study aims were to determine the association of: (1) functional status at listing with waitlist and post-transplant outcomes, and (2) functional status at transplant with post-transplant outcomes in pediatric heart transplantation. METHODS: Retrospective United Network of Organ Sharing database study of pediatric patients listed for heart transplant between 2005 and 2019 with Lansky Play Performance Scale (LPPS) scores at listing. Standard statistical methods were used to assess relationships between LPPS and outcomes (waitlist and post-transplant). Negative waitlist outcome was defined as death or removal from waitlist due to clinical deterioration. RESULTS: There were 4,169 patients identified, including 1,080 with LPPS 80-100 (normal activity), 1,603 with LPPS 50-70 (mild limitations), and 1,486 with LPPS 10-40 (severe limitations). LPPS 10-40 correlated with negative waitlist outcomes (HR 1.69, CI 1.59-1.80, p < 0.0001). While LLPS at listing had no association with post-transplant survival, those with LPPS 10-40 at transplant had inferior 1-year post-transplant survival compared to those with LPPS ≥50 (92% vs 95%-96%, p = 0.0011). Functional status was an independent predictor of post-transplant outcomes in patients with cardiomyopathy. A functional improvement of ≥20 points between listing and transplant (N = 770, 24%) was associated with higher 1-year post-transplant survival (HR 1.63, 95% CI: 1.10-2.41, p = 0.018). CONCLUSIONS: Functional status is associated with waitlist and post-transplant outcomes. Interventions targeting functional impairment may improve pediatric heart transplantation outcomes.

Multidisciplinary Stroke Pathway for Children Supported With Ventricular Assist Devices.

Mechanical circulatory support (MCS), including ventricular assist device (VAD) support, is a leading cause of stroke in children; however, existing pediatric stroke recommendations do not apply to many pediatric VAD patients. We sought to develop a multidisciplinary pathway to improve timely and effective acute stroke care and examine the early performance of the pathway in expediting stroke care. Stakeholders from pediatric heart failure, cardiac intensive care, neurology, interventional radiology, neuroradiology, neurosurgery, pharmacy, and adult VAD care convened at Stanford University in August 2017 to discuss the challenges of providing high-quality acute stroke care to children on VAD support, and to develop multidisciplinary acute stroke pathways. Stakeholders identified multiple barriers to providing timely acute stroke care to pediatric VAD patients. These include delayed recognition of stroke, and lack of clarity related to the optimal imaging technique, when to emergently reverse antithrombotic therapy (AT), pediatric indications for thrombectomy and cranial decompression, and strategies to avoid unnecessary serial CTS. Four stroke pathways were created including evaluation and management of the pediatric patient with (1) an acute neurologic change before an imaging diagnosis; (2) an arterial ischemic stroke (AIS); (3) an intracerebral hemorrhage (ICH); and (4) a subdural hematoma (SDH). With the implementation of the stroke pathway, the median time-to-first-CT image decreased by 43 minutes from 66 to 23 minutes ( P < 0.001) while the proportion with a CT within 30 minutes increased from 0% to 67% ( P < 0.001). Despite a variety of challenges, multidisciplinary consensus can be achieved on a rapid stroke management pathway for children on VAD support that addresses important barriers to timely stroke care. Although too few stoke events occurred to differentiate clinical outcomes, the time-to-first-CT image was significantly shorter after pathway implementation.

Considerations for Advanced Heart Failure Consultation in Individuals With Fontan Circulation: Recommendations From ACTION.

Individuals with Fontan circulation are at risk of late mortality from both cardiac and noncardiac causes. Despite the known risk of mortality, referral indications for advanced heart failure care vary between centers, and many individuals die from Fontan circulation-related complications either after late consideration for advanced heart failure therapies or having never seen a heart failure specialist. There is a critical need for guidelines to direct appropriately timed referral for advanced heart failure consultation. The Advanced Cardiac Therapies Improving Outcomes Network (ACTION) Fontan Committee has developed recommended thresholds for advanced heart failure referral to guide primary cardiologists. These recommendations are divided into 4 categories of clinical Fontan circulatory dysfunction including (1) cardiac/systemic ventricular dysfunction, (2) Fontan pathway dysfunction, (3) lymphatic dysfunction, and (4) extracardiac dysfunction.

The teammate trial: Study design and rationale tacrolimus and everolimus against tacrolimus and MMF in pediatric heart transplantation using the major adverse transplant event (MATE) score.

BACKGROUND: Currently there are no immunosuppression regimens FDA-approved to prevent rejection in pediatric heart transplantation (HT). In recent years, everolimus (EVL) has emerged as a potential alternative to standard tacrolimus (TAC) as the primary immunosuppressant to prevent rejection that may also reduce the risk of cardiac allograft vasculopathy (CAV), chronic kidney disease (CKD) and cytomegalovirus (CMV) infection. However, the 2 regimens have never been compared head-to-head in a randomized trial. The study design and rationale are reviewed in light of the challenges inherent in rare disease research. METHODS: The TEAMMATE trial (IND 127980) is the first multicenter randomized clinical trial (RCT) in pediatric HT. The primary purpose is to evaluate the safety and efficacy of EVL and low-dose TAC (LD-TAC) compared to standard-dose TAC and mycophenolate mofetil (MMF). Children aged <21 years at HT were randomized (1:1 ratio) at 6 months post-HT to either regimen, and followed for 30 months. Children with recurrent rejection, multi-organ transplant recipients, and those with an estimated glomerular filtration rate (eGFR) <30 mL/min/1.73m2 were excluded. The primary efficacy hypothesis is that, compared to TAC/MMF, EVL/LD-TAC is more effective in preventing 3 MATEs: acute cellular rejection (ACR), CKD and CAV. The primary safety hypothesis is that EVL/LD-TAC does not have a higher cumulative burden of 6 MATEs (antibody mediated rejection [AMR], infection, and post-transplant lymphoproliferative disorder [PTLD] in addition to the 3 above). The primary endpoint is the MATE score, a composite, ordinal surrogate endpoint reflecting the frequency and severity of MATEs that is validated against graft loss. The study had a target sample size of 210 patients across 25 sites and is powered to demonstrate superior efficacy of EVL/LD-TAC. Trial enrollment is complete and participant follow-up will be completed in 2023. CONCLUSION: The TEAMMATE trial is the first multicenter RCT in pediatric HT. It is anticipated that the study will provide important information about the safety and efficacy of everolimus vs tacrolimus-based regimens and will provide valuable lessons into the design and conduct of future trials in pediatric HT.

Lessons Learned from Managing Antithrombotic Therapy in Children Supported with Pediatric Ventricular Assist Devices.

Stroke, thromboembolism, and bleeding are the most recognized complications associated with pediatric ventricular assist devices (VADs) and the leading cause of death and disability on VAD support. Recently, newer antithrombotic strategies like bivalirudin have emerged that appear to be associated with a reduction in the neurologic event rates, especially for smaller pediatric-specific VADs like the Berlin Heart and PediMag/CentriMag systems where the risk of stroke is the highest. While contemporary antithrombotic therapies have likely contributed to lowering adverse event rates, we speculate that clotting and bleeding adverse events may have dropped because of a variety of other seemingly small changes to antithrombotic management that are independent of the antithrombotic agents used. This view is supported by recent reports documenting low stroke rates with anticoagulants other than bivalirudin, a drug that may have a wider therapeutic window but is not available in all locations throughout the world. The primary purpose of this report is 1) to summarize contemporary antithrombotic regimens used for smaller pediatric VADs today associated with low event rates in the United States and abroad and () to review 10 practical lessons learned and pitfalls to avoid that we believe to be important to reducing bleeding and clotting events based on our collective experience managing pediatric VADs over the past 20 years irrespective of the antithrombotic agents used.

Adverse Events Associated with Cardiac Catheterization in Children Supported with Ventricular Assist Devices.

Children on ventricular assist device (VAD) support can present several unique challenges, including small patient size, univentricular or biventricular congenital heart disease (1V- or 2V-CHD) and need for biventricular VAD (BiVAD) support. While cardiac catheterization can provide valuable information, it is an invasive procedure with inherent risks. We sought to evaluate the safety of catheterization in pediatric patients on VAD support. We performed a retrospective review of patients on VAD support who underwent catheterization at Lucile Packard Children's Hospital between January 1, 2014 and September 1, 2019. Using definitions adapted from Pedimacs, adverse events (AEs) after catheterization were identified, including arrhythmia; major bleeding or acute kidney injury within 24 hours; respiratory failure persisting at 24 hours; and stroke, pericardial effusion, device malfunction, bacteremia or death within 7 days. AEs were categorized as related or unrelated to catheterization. Sixty procedures were performed on 39 patients. Underlying diagnoses were dilated cardiomyopathy (48%), 1V-CHD (35%), 2V-CHD (8%), and other (8%). Devices were implantable continuous flow (72%), paracorporeal pulsatile (18%) and paracorporeal continuous flow (10%). Catheterizations were performed on patients in the ICU (60%), on inotropic support (42%), with deteriorating clinical status (37%) and on BiVAD support (12%). There were 9 AEs possibly related to catheterization including 6 episodes of respiratory failure, 2 major bleeding events, and 1 procedural arrhythmia. AE occurrence was associated with ICU status ( P = 0.01), BiVAD support ( P = 0.04) and procedural indication to evaluate worsening clinical status ( P = 0.04). Despite high medical acuity, catheterization can be performed with an acceptable AE profile in children on VAD support.

Consensus Statement: Hemostasis Trial Outcomes in Cardiac Surgery and Mechanical Support.

BACKGROUND: Research evaluating hemostatic agents for the treatment of clinically significant bleeding has been hampered by inconsistency and lack of standardized primary clinical trial outcomes. Clinical trials of hemostatic agents in both cardiac surgery and mechanical circulatory support, such as extracorporeal membrane oxygenation and ventricular assist devices, are examples of studies that lack implementation of universally accepted outcomes. METHODS: A subgroup of experts convened by the National Heart, Lung, and Blood Institute and the US Department of Defense developed consensus recommendations for primary outcomes in cardiac surgery and mechanical circulatory support. RESULTS: For cardiac surgery the primary efficacy endpoint of total allogeneic blood products (units vs mL/kg for pediatric patients) administered intraoperatively and postoperatively through day 5 or hospital discharge is recommended. For mechanical circulatory support outside the perioperative period the recommended primary outcome for extracorporeal membrane oxygenation is a 5-point ordinal score of thrombosis and bleeding severity adapted from the Common Terminology Criteria for Adverse Events version 5.0. The recommended primary endpoint for ventricular assist device is freedom from disabling stroke (Common Terminology Criteria for Adverse Events AE ≥ grade 3) through day 180. CONCLUSIONS: The proposed composite risk scores could impact the design of upcoming clinical trials and enable comparability of future investigations. Harmonizing and disseminating global consensus definitions and management guidelines can also reduce patient heterogeneity that would confound standardized primary outcomes in future research.

Clinical and hemodynamic characteristics of the pediatric failing Fontan.

AIM: To describe the clinical and hemodynamic characteristics of Fontan failure in children listed for heart transplant. METHODS: In a nested study of the Pediatric Heart Transplant Society, 16 centers contributed information on Fontan patients listed for heart transplant between 2005and 2013. Patients were classified into four mutually exclusive phenotypes: Fontan with abnormal lymphatics (FAL), Fontan with reduced systolic function (FRF), Fontan with preserved systolic function (FPF), and Fontan with "normal" hearts (FNH). Primary outcome was waitlist and post-transplant mortality. RESULTS: 177 children listed for transplant were followed over a median 13 (IQR 4-31) months, 84 (47%) were FAL, 57 (32%) FRF, 22 (12%) FNH, and 14 (8%) FPF. Hemodynamic characteristics differed between the 4 groups: Fontan pressure (FP) was most elevated with FPF (median 22, IQR 18-23, mmHg) and lowest with FAL (16, 14-20, mmHg); cardiac index (CI) was lowest with FRF (2.8, 2.3-3.4, L/min/m2). In the entire cohort, 66% had FP >15 mmHg, 21% had FP >20 mmHg, and 10% had CI <2.2 L/min/m2. FRF had the highest risk of waitlist mortality (21%) and FNH had the highest risk of post-transplant mortality (36%). CONCLUSIONS: Elevated Fontan pressure is more common than low cardiac output in pediatric failing Fontan patients listed for transplant. Subtle hemodynamic differences exist between the various phenotypes of pediatric Fontan failure. Waitlist and post-transplant mortality risks differ by phenotype.

Recommended primary outcomes for clinical trials evaluating hemostatic blood products and agents in patients with bleeding: Proceedings of a National Heart Lung and Blood Institute and US Department of Defense Consensus Conference.

ABSTRACT: High-quality evidence guiding optimal transfusion and other supportive therapies to reduce bleeding is needed to improve outcomes for patients with either severe bleeding or hemostatic disorders that are associated with poor outcomes. Alongside challenges in performing high-quality clinical trials in patient populations who are at risk of bleeding or who are actively bleeding, the interpretation of research evaluating hemostatic agents has been limited by inconsistency in the choice of primary trial outcomes. This lack of standardization of primary endpoints or outcomes decreases the ability of clinicians to assess the validity of endpoints and compare research results across studies, impairs meta-analytic efforts, and, ultimately, delays the translation of research results into clinical practice. To address this challenge, an international panel of experts was convened by the National Heart Lung and Blood Institute and the US Department of Defense on September 23 and 24, 2019, to develop expert opinion, consensus-based recommendations for primary clinical trial outcomes for pivotal trials in pediatric and adult patients with six categories in various clinical settings. This publication documents the conference proceedings from the workshop funded by the National Heart Lung and Blood Institute and the US Department of Defense that consolidated expert opinion regarding clinically meaningful outcomes across a wide range of disciplines to provide guidance for outcomes of future trials of hemostatic products and agents for patients with active bleeding.

Establishing Baseline Metrics of Heart Failure Medication Use in Children: A Collaborative Effort from the ACTION Network.

Heart failure metrics specific to the pediatric population are required to successfully implement quality improvement initiatives in children with heart failure. Medication use at the time of discharge following admission for decompensated heart failure has been identified as a potential quality metric in this population. This study aimed to report medication use at discharge in the current era for children admitted with acute decompensated heart failure. All patients < 21 years of age with an index admission (1/1/2011-12/31/2019) for acute heart failure and a coexisting diagnosis of cardiomyopathy were identified from the Pediatric Health Information System. Medication use patterns were described and compared across age groups and centers. A total of 2288 patients were identified for inclusion. An angiotensin-converting enzyme inhibitor or an angiotensin receptor blocker (ACEi/ARB) was prescribed in 1479 (64.6%), beta blocker in 1132 (49.5%), and mineralocorticoid receptor antagonist (MRA) in 864 (37.8%) patients at discharge. The use of ACEi/ARB at discharge has decreased over time (64.6% vs. 69.6%, p = 0.001) and the use of beta blockers has increased (49.5% vs. 36.8%, p < 0.001) compared to a historical cohort (2001-2010). There is considerable variability in medication use across centers with an overall increase in beta blocker and decrease in ACEi/ARB use over time. Collaborative efforts are needed to standardize care and define quality metrics to identify best practices in the management of pediatric heart failure.

The Stanford acute heart failure symptom score for patients hospitalized with heart failure.

BACKGROUND: Currently, there are no simple tools to evaluate the acute heart failure (HF) symptom severity in children hospitalized with acute decompensated HF (ADHF). We sought to develop an inpatient HF score (HFS) that could be used as a clinical tool and for clinical trials. METHODS: Pediatric HF clinicians at Stanford reviewed the limitations of existing HFSs, which include lack of calibration to the inpatient setting, omission of gastrointestinal symptoms, need for multiple age-based tools, and scores that prioritize treatment intensity over patient symptoms. To address these, we developed an acute HFS corresponding to the 3 cardinal symptoms of HF: difficulty with breathing, feeding, and activity. The score was iteratively improved over a 3-year pilot phase until no further changes were made. The inter-rater reliability (IRR) across a range of providers was assessed using the final version. Peak HFSs were analyzed against mortality and length of stay (LOS) for all pediatric HF discharges between July and October 2019. RESULTS: The final HFS was a 4-point ordinal severity score for each of the 3 symptom domains (total score 0-12). Among clinicians who scored 12 inpatients with ADHF simultaneously, the intraclass correlation (ICC) was 0.94 (respiratory ICC = 0.89, feeding ICC = 0.85, and activity ICC = 0.80). Score trajectory reflected our clinical impression of patient response to HF therapies across a range of HF syndromes including 1- and 2-ventricle heart disease and reduced or preserved ejection fraction. Among the 28 patients hospitalized during a 3-months period (N = 28), quartiles of peak score were associated with LOS (p < 0.01) and in-hospital mortality (p < 0.01): HFS 0 to 3 (median LOS of 5 days and mortality of 0%), HFS 4 to 6 (median LOS of 18 days and mortality of 0%), HFS 5 to 9 (median LOS of 29 days and mortality of 23%), and HFS 10 to 12 (median LOS of 121 days and mortality of 50%). CONCLUSION: This simple acute HFS may be a useful tool to quantify and monitor day-to-day HF symptoms in children hospitalized with ADHF regardless of etiology or age group. The score has excellent IRR across provider levels and is associated with major hospital outcomes supporting its clinical validity. Validation in a multicenter cohort is warranted.

The Creation of a Pediatric Health Care Learning Network: The ACTION Quality Improvement Collaborative.

Improving the outcomes of pediatric patients with congenital heart disease with end-stage heart failure depends on the collaboration of all stakeholders; this includes providers, patients and families, and industry representatives. Because of the rarity of this condition and the heterogeneity of heart failure etiologies that occur at pediatric centers, learnings must be shared between institutions and all disciplines to move the field forward. To foster collaboration, excel discovery, and bring data to the bedside, a new, collaborative quality improvement science network-ACTION (Advanced Cardiac Therapies Improving Outcomes Network)-was developed to meet the needs of the field. Existing gaps in care and the methods of improvement that will be used are described, along with the mission and vision, utility of real-world data for regulatory purposes, and the organizational structure of ACTION is described.

Impact of Cardiac Resynchronization Therapy on Heart Transplant-Free Survival in Pediatric and Congenital Heart Disease Patients.

BACKGROUND: Cardiac resynchronization therapy (CRT) studies in pediatric or congenital heart disease patients have shown an improvement in ejection fraction and heart failure symptoms. However, a survival benefit of CRT in this population has not been established. This study aimed to evaluate the impact of CRT upon heart transplant-free survival in pediatric and congenital heart disease patients, using a propensity score-matched (PSM) analysis. METHODS: This single-center study compared CRT patients (implant date, 2004-2017) and controls, matched by 1:1 PSM using 21 comprehensive baseline indices for risk stratification. CRT patients were <21 years of age or had congenital heart disease, had systemic ventricular ejection fraction <45%, symptomatic heart failure, and had significant electrical dyssynchrony, all before CRT implant. Controls were screened from nonselective imaging and ECG databases. Controls were retrospectively enrolled when they achieved the same inclusion criteria at an outpatient clinical encounter, within the same time period. RESULTS: Of 133 patients who received CRT during the study period, 84 met all study inclusion criteria. One hundred thirty-three controls met all criteria at an outpatient encounter. Following PSM, 63 matched CRT-control pairs were identified with no significant difference between groups across all baseline indices. Heart transplant or death occurred in 12 (19%) PSM-CRT subjects and 37 (59%) PSM-controls with a median follow-up of 2.7 years (quartiles, 0.8-6.1 years). CRT was associated with markedly reduced risk of heart transplant or death (hazard ratio, 0.24 [95% CI, 0.12-0.46]; P<0.001). There was no CRT procedural mortality and 1 system infection at 54 months post-implant. CONCLUSIONS: In pediatric and congenital heart disease patients with symptomatic systolic heart failure and electrical dyssynchrony, CRT was associated with improved heart transplant-free survival. Visual Overview: A visual overview is available for this article.

A Predictive Model for Intracardiac Pressures in Patients Free From Rejection or Allograft Vasculopathy After Pediatric Heart Transplantation.

BACKGROUND: Despite the routine use of hemodynamic assessment in pediatric heart transplant (HT) patients, expected intracardiac pressure measurements in patients free of significant complications are incompletely described. A better understanding of the range of intracardiac pressures in these HT patients is important for the clinical interpretation of these indices and consequent management of patients. METHODS: We conducted a retrospective chart review of pediatric HT recipients who had undergone HT between January 2010 and December 2015 at Lucile Packard Children's Hospital. We analyzed intracardiac pressures measured in the first 12 mo after HT. We excluded those with rejection, graft coronary artery disease, mechanical support, or hemodialysis. We used a longitudinal general additive model with bootstrapping technique to generate age and donor-recipient size-specific curves to characterize filling pressures through 1-y post-HT. RESULTS: Pressure measurements from the right atrium, pulmonary artery, and pulmonary capillary wedge pressure were obtained in 85 patients during a total of 829 catheterizations. All pressure measurements were elevated in the immediate post-HT period and decreased to a stable level by post-HT day 90. Pressure measurements were not affected by age group, donor-recipient size differences, or ischemic time. CONCLUSIONS: Intracardiac pressures are elevated in the early post-HT period and decrease to levels typical of the native heart by 90 d. Age, donor-to-recipient size differences, and ischemic time do not contribute to differences in expected intracardiac pressures in the first year post-HT.