Mechanical Ventilation and Outcomes of Children Who Undergo Ventricular Assist Device Placement: 2014-2020 Linked Analysis From the Advanced Cardiac Therapies Improving Outcomes Network and Pediatric Cardiac Critical Care Consortium Registries

OBJECTIVES

Placement of a ventricular assist device (VAD) improves outcomes in children with advanced heart failure, but adverse events remain important consequences. Preoperative mechanical ventilation (MV) increases mortality, but it is unknown what impact prolonged postoperative MV has.

DESIGN

Advanced Cardiac Therapies Improving Outcomes Network (ACTION) and Pediatric Cardiac Critical Care Consortium (PC4) registries were used to identify and link children with initial VAD placement admitted to the cardiac ICU (CICU) from August 2014 to July 2020. Demographics, cardiac diagnosis, preoperative and postoperative CICU courses, and outcomes were compiled. Univariable and multivariable statistics assessed association of patient factors with prolonged postoperative MV. Multivariable logistic regression sought independent associations with outcomes.

SETTING

Thirty-five pediatric CICUs across the United States and Canada.

PATIENTS

Children on VADs included in both registries.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Two hundred forty-eight ACTION subjects were linked to a matching patient in PC4. Median (interquartile) age 7.7 years (1.5-15.5 yr), weight 21.3 kg (9.1-58 kg), and 56% male. Primary diagnosis was congenital heart disease (CHD) in 35%. Pre-VAD explanatory variables independently associated with prolonged postoperative MV included: age (incidence rate ratio [IRR], 0.95; 95% CI, 0.93-0.96; p < 0.01); preoperative MV within 48 hours (IRR, 2.76; 95% CI, 1.59-4.79; p < 0.01), 2-7 days (IRR, 1.82; 95% CI, 1.15-2.89; p = 0.011), and greater than 7 days before VAD implant (IRR, 2.35; 95% CI, 1.62-3.4; p < 0.01); and CHD (IRR, 1.96; 95% CI, 1.48-2.59; p < 0.01). Each additional day of postoperative MV was associated with greater odds of mortality (odds ratio [OR], 1.09 per day; p < 0.01) in the full cohort. We identified an associated greater odds of mortality in the 102 patients with intracorporeal devices (OR, 1.24; 95% CI, 1.04-1.48; p = 0.014), but not paracorporeal devices (77 patients; OR, 1.04; 95% CI, 0.99-1.09; p = 0.115).

CONCLUSIONS

Prolonged MV after VAD placement is associated with greater odds of mortality in intracorporeal devices, which may indicate inadequacy of cardiopulmonary support in this group. This linkage provides a platform for future analyses in this population.

Achieving Consensus: Severity-Graded Definitions of Fontan-Associated Complications to Characterize Fontan Circulatory Failure

BACKGROUND

Fontan physiology leads to chronic changes in other organ systems that may affect long-term survival and the success of heart transplantation. Inadequate assessment and treatment of the extra-cardiac effects of Fontan may contribute to poor outcomes. Severity-graded/ordinal consensus definitions of Fontan complications are lacking, which limits understanding of how Fontan-specific morbidity affects patients' outcomes.

METHODS AND RESULTS

A panel of Fontan patient and physiology experts, including pediatric, adult congenital, heart failure, and critical-care cardiology as well as pediatric nephrology, hepatology and psychology, convened to develop definitions of Fontan complications. Definitions were created by using a severity-graded ordinal scale: grade 1, mild; grade 2, moderate; grade 3, severe; grade 4, disabling or life threatening. Following definition creation, a second panel of 21 experts in Fontan circulatory failure used a modified Delphi methodology to modify and vote on definitions until consensus (> 90% agreement without recommended further modification) was reached on final definitions. After 3 rounds of modifications and voting, consensus agreement was achieved on all Fontan-specific definitions. The defined complications and morbidities of Fontan include: anatomic Fontan pathway obstruction, cyanosis, systemic venous abnormalities resulting from venous insufficiency, atrial arrhythmia, ventricular arrhythmia, bradycardia, chronic pleural effusions, chronic ascites, protein-losing enteropathy, plastic bronchitis, hemoptysis and pulmonary hemorrhage, sleep apnea, Fontan-associated liver disease, portal and hepatic variceal disease, acute kidney injury affecting clinical treatment, polycythemia, thrombotic disease, recurrent or severe bacterial infection, skin atrophy, adrenal insufficiency, physical impact of previous stroke, mood/behavior disorder, and neurodevelopmental disorder.

CONCLUSION

Consensus and severity-graded definitions of Fontan-specific cardiac and extra-cardiac complications were achieved and are available for use in research. They will allow future robust analyses of Fontan patient outcomes.

Successful implementation of telehealth visits in the paediatric heart failure and heart transplant population

The Advanced Cardiac Therapies Improving Outcomes Network (ACTION) and Pediatric Heart Transplant Society (PHTS) convened a working group at the beginning of 2020 during the COVID-19 pandemic, with the aim of using telehealth as an alternative medium to provide quality care to a high-acuity paediatric population receiving advanced cardiac therapies. An algorithm was developed to determine appropriateness, educational handouts were developed for both patients and providers, and post-visit surveys were collected. Telehealth was found to be a viable modality for health care delivery in the paediatric heart failure and transplant population and has promising application in the continuity of follow-up, medication titration, and patient education/counselling domains.

Reducing donor acceptance practice variation - Learnings from a discussion forum

PURPOSE

Although waitlist mortality is unacceptably high, nearly half of donor heart offers are rejected by pediatric heart transplant centers. The Advanced Cardiac Therapy Improving Outcome Network (ACTION) and Pediatric Heart Transplant Society (PHTS) convened a multi-institutional donor decision discussion forum (DDDF) aimed at assessing donor acceptance practices and reducing practice variation.

METHODS

A 1-h-long virtual DDDF for providers across North America, the United Kingdom, and Brazil was held monthly. Each session typically included two case presentations posing a real-world donor decision challenge. Attendees were polled before the presenting center's decision was revealed. Group discussion followed, including a review of relevant literature and PHTS data. Metrics of participation, participant agreement with presenting center decisions, and impact on future decision-making were collected and analyzed.

RESULTS

Over 2 years, 41 cases were discussed. Approximately 50 clinicians attended each call. Risk factors influencing decision-making included donor quality (10), size discrepancy (8), and COVID-19 (8). Donor characteristics influenced 63% of decisions, recipient factors 35%. Participants agreed with the decision made by the presenting center only 49% of the time. Post-presentation discussion resulted in 25% of participants changing their original decision. Survey conducted reported that 50% respondents changed their donor acceptance practices.

CONCLUSION

DDDF identified significant variation in pediatric donor decision-making among centers. DDDF may be an effective format to reduce practice variation, provide education to decision-makers, and ultimately increase donor utilization.

An integrated program to expand donor utilization in pediatric heart transplantation: Case report of successful transplant with multiple donor risk factors

BACKGROUND

Pediatric heart transplantation (HT) continues to be limited by the shortage of donor organs, distance constraints, and the number of potential donor offers that are declined due to the presence of multiple risk factors.

METHODS

We report a case of successful pediatric HT in which multiple risk factors were mitigated through a combination of innovative donor utilization improvement strategies.

RESULTS

An 11-year-old, 25-kilogram child with cardiomyopathy and pulmonary hypertension, on chronic milrinone therapy and anticoagulated with apixaban, was transplanted with a heart from a Hepatitis C virus positive donor and an increased donor-to-recipient weight ratio. Due to extended geographic distance, an extracorporeal heart preservation system (TransMedics™ OCS Heart) was used for procurement. No significant bleeding was observed post-operatively, and she was discharged by post-operative day 15 with normal biventricular systolic function. Post-transplant Hepatitis C virus seroconversion was successfully treated.

CONCLUSIONS

Heart transplantation in donors with multiple risk factor can be achieved with an integrative team approach and should be taken into consideration when evaluating marginal donors in order to expand the current limited donor pool in pediatric patients.

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.

Widening care gap in VAD therapy

BACKGROUND

The removal of the HeartWare ventricular assist device (HVAD) due to pump malfunctions and inferior outcomes compared to HeartMate 3 (HM3) in adults has created a care gap for younger patients. It is unclear if the reported HVAD survival differs by age and if the initial experience with HM3 can bridge the gap.

METHODS

Using the Society of Thoracic Surgeons (STS) Intermacs and Pedimacs registries, durable ventricular assist device (VAD) implants between September 2012 and December 2021 were identified. Young adults (YA) were defined as <40 years old in Intermacs. Patients were excluded if they had an isolated right VAD (RVAD) or were implanted as destination therapy (DT). Survival analysis by Kaplan-Meier (KM) and competing outcomes curves was performed, and 1-year survival is reported.

RESULTS

The Intermacs cohort consisted of YA (n = 1226; HVAD 818; HM3 408) with a median age of YA of 32.07 (26.66-36.27) years and weight (wt) of 83.2 (68-104.2) kg. Most had cardiomyopathy (CM) (92.2%). The Pedimacs cohort was 668 patients (median age 9.47 [1.82-14.23] years, wt 27.2 [10-57.05] kg), and most also had CM (70.5%). Device breakdown included HVAD (n = 326), Berlin EXCOR (n = 277), and HM3 (n = 65). HVAD survival differed by age in adults, with YA fairing better than adults >40 years old (88.8% vs 79.4% at 1 year, p < 0.0001). YA survival was also better compared to Pedimacs patient (88.9% vs 83.7%, p = 0.0002), but when competing events were analyzed, mortality was similar to YA (9.2% vs 9.6%, p = 0.1) with a higher proportion of patient undergoing transplant at 1 year in Pedimacs (74% vs 31.3%, p < 0.0001). Survival by device differed between HVAD and HM3 in YA (88.8% vs 94.4%, p = 0.0025). This difference in device survival was not seen in all children (83.7% vs 87.3%, p = 0.21), including those ≥25 kg. Adverse event profiles also differed across the groups with adults seeing less adverse events with the HM3, but the same was not found (including stroke) in the pediatric cohort. Survival outcomes for patients between 10 and 25 kg were similar with the HVAD compared to the Berlin Heart EXCOR (p = 0.4290), with similarities in stroke risk.

CONCLUSION

The removal of the HVAD device may result in a care gap in younger patient whose survival outcomes do not mirror that of older adults. The HM3 can fill a portion of this gap with good survival, but there remains a subset of pediatric patients that, based on initial HM3 use, will no longer have access to intracorporeal support and therefore, despite reasonable outcomes with the Berlin Heart EXCOR, will not be able to be discharged home. Lastly, it is essential that future changes to the availability of devices take into account the various patient populations that utilize the device to avoid unintended consequences of access inequality.

Weight Matching in Infant Heart Transplantation: A National Registry Analysis

BACKGROUND

Infants account for a significant proportion of pediatric heart transplantation but also suffer from a high waitlist mortality. Donor oversizing by weight-based criteria is common practice in transplantation and is prevalent in this group. We sought to analyze the impact of oversizing on outcomes in infants.

METHODS

Infant heart transplantations reported to the United Network for Organ Sharing from January 1994 to September 2019 were retrospectively analyzed. 2384 heart transplantation recipients were divided into quintiles (Q1-Q5) on the basis of donor-to-recipient weight ratio (DRWR). Multivariate Cox regression was used to estimate the effect of DRWR. The primary end point was graft survival at 1 year.

RESULTS

The median DRWR for each quintile was 0.90 (0.37-1.04), 1.17 (1.04-1.29), 1.43 (1.29-1.57), 1.74 (1.58-1.97), and 2.28 (1.97-5.00). Pairwise comparisons showed improved survival for Q3 and Q4 over each of the bottom 2 quintiles and the top quintile. Regression analyses found that Q3 and Q4 were protective against graft failure compared with the bottom 2 quintiles. There was no difference in hazard among the top 3 quintiles. Significant covariates included primary diagnosis, ischemia time, serum bilirubin level, transplantation year, mechanical ventilation at transplantation, and extracorporeal membrane oxygenation at transplantation. Sex, female-to-male transplantation, and mechanical circulatory support at transplantation were not significant in univariate analyses.

CONCLUSIONS

Modest oversizing by DRWR (1.29-1.97) is associated with increased survival and lower risk in infant heart transplantation. Additional investigation is needed to establish best practices for size matching in this population.

Differences in Quality of Life in Children Across the Spectrum of Congenital Heart Disease

OBJECTIVE

To create complexity groups based upon a patient's cardiac medical history and to test for group differences in health-related quality of life (HRQOL).

METHODS

Patients 8-18 years with congenital heart disease (CHD) and parent-proxies from the Pediatric Cardiac Quality of Life Inventory (PCQLI) Testing Study were included. Outcome variables included PCQLI Total, Disease Impact, and Psychosocial Impact scores. Using a patient's medical history (cardiac, neurologic, psychological, and cognitive diagnosis), latent class analysis (LCA) was used to create CHD complexity groups. Covariates included demographics and burden of illness (number of: school weeks missed, physician visits in the past year, and daily medications). Generalized estimation equations tested for differences in burden of illness and patient and parent-proxy PCQLI scores.

RESULTS

Using 1482 CHD patients (60% male; 84% white; age 12.3 ± 3.0 years), latent class analysis (LCA) estimates showed 4 distinct CHD complexity groups (Mild, Moderate 1, Moderate 2, and Severe). Increasing CHD complexity was associated with increased risk of learning disorders, seizures, mental health problems, and history of stroke. Greater CHD complexity was associated with greater burden of illness (P < .01) and lower patient- and parent-reported PCQLI scores (P < .001).

CONCLUSIONS

LCA identified 4 congenital heart disease (CHD) complexity groupings. Increasing CHD complexity was associated with higher burden of illness and worse patient- and parent-reported HRQOL.

Patient and parent-reported outcomes in paediatric ventricular assist device support: a multi-center ACTION learning network feasibility and pilot experience

BACKGROUND

Patient- and proxy-reported outcomes (PROs) are an important indicator of healthcare quality and can be used to inform treatment. Despite the widescale use of PROs in adult cardiology, they are underutilised in paediatric cardiac care. This study describes a six-center feasibility and pilot experience implementing PROs in the paediatric and young adult ventricular assist device population.

METHODS

The Advanced Cardiac Therapies Improving Outcomes Network (ACTION) is a collaborative learning network comprised of 55 centres focused on improving clinical outcomes and the patient/family experience for children with heart failure and those supported by ventricular assist devices. The development of ACTION's PRO programme via engagement with patient and parent stakeholders is described. Pilot feasibility, patient/parent and clinician feedback, and initial PRO findings of patients and families receiving paediatric ventricular assist support across six centres are detailed.

RESULTS

Thirty of the thirty-five eligible patients (85.7%) were enrolled in the PRO programme during the pilot study period. Clinicians and participating patients/parents reported positive experiences with the PRO pilot programme. The most common symptoms reported by patients/parents in the first month post-implant period included limitations in activities, dressing change distress, and post-operative pain. Poor sleep, dressing change distress, sadness, and fatigue were the most common symptoms endorsed >30 days post-implant. Parental sadness and worry were notable throughout the entirety of the post-implant experience.

CONCLUSIONS

This multi-center ACTION learning network-based PRO programme demonstrated initial success in this six-center pilot study experience and yields important next steps for larger-scale PRO collection, research, and clinical intervention.

Pulmonary Vasodilator Therapy in Pediatric Patients on Ventricular Assist Device Support: A Single-Center Experience and Proposal for Use

Pediatric precapillary pulmonary hypertension can develop in response to systemic atrial hypertension. Systemic atrial decompression following ventricular assist device (VAD) implantation may not sufficiently lower pulmonary vascular resistance (PVR) to consider heart transplant candidacy. Prostacyclins have been used in adult VAD patients with success, but pediatric data on safety and efficacy in this population are limited. We sought to describe our center's experience to show its safety and to present our current protocol for perioperative use. We reviewed our use of prostacyclin therapy in pediatric patients on VAD support with high PVR from 2016 to 2021. Of the 17 patients who met inclusion, 12 survived to transplant and 1 is alive with VAD in situ . All patients survived posttransplant. With continuous intravenous (IV) epoprostenol or treprostinil therapy, there were no bleeding complications or worsening of end-organ function. A significant reduction was observed in vasoactive inotropic scores by 49% in the first 24 hours post-prostacyclin initiation. The proportion of patients surviving to transplant in this high-risk cohort is favorable. In conclusion, prostacyclins may be safe to use in patients with elevated PVR as part of their VAD and transplant course and may provide a transplant option in those otherwise not candidates.

Taking ACTION: A Prognostic Tool for Pediatric Ventricular Assist Device Mortality

We sought to develop a contemporary risk assessment tool for use in pediatric ventricular assist device (VAD) candidates to estimate risk for mortality on the device using readily available preimplantation clinical data. Training and testing datasets were created from Advanced Cardiac Therapies Improving Outcomes Network (ACTION) registry data on patients supported with a VAD from 2012 to 2021. Potential risk factors for mortality were assessed and incorporated into a simplified risk prediction model utilizing an open-source, gradient-boosted decision tree machine learning library, known as random forest. Predictive performance was assessed by the area under the receiver operating characteristic curve in the testing dataset. Nine significant risk factors were included in the final predictive model which demonstrated excellent discrimination with an area under the curve of 0.95. In addition to providing a framework for establishing pediatric-specific risk profiles, our model can help inform team expectations, guide optimal patient selection, and ultimately improve patient outcomes.

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.

Initial multicenter experience with ventricular assist devices in children and young adults with muscular dystrophy: An ACTION registry analysis

PURPOSE

Cardiac disease results in significant morbidity and mortality in patients with muscular dystrophy (MD). Single centers have reported their ventricular assist device (VAD) experience in specific MDs and in limited numbers. This study sought to describe the outcomes associated with VAD therapy in an unselected population across multiple centers.

METHODS

We examined outcomes of patients with MD and dilated cardiomyopathy implanted with a VAD at Advanced Cardiac Therapies Improving Outcomes Network (ACTION) centers from 9/2012 to 9/2020.

RESULTS

A total of 19 VADs were implanted in 18 patients across 12 sites. The majority of patients had dystrophinopathy (66%) and the median age at implant was 17.2 years (range 11.7-29.5). Eleven patients were non-ambulatory (61%) and 6 (33%) were on respiratory support pre-VAD. Five (28%) patients were implanted as a bridge to transplant, 4 of whom survived to transplant. Of 13 patients implanted as bridge to decision or destination therapy, 77% were alive at 1 year and 69% at 2 years. The overall frequencies of positive outcome (transplanted or alive on device) at 1 year and 2 years were 84% and 78%, respectively. Two patients suffered a stroke, 2 developed sepsis, 1 required tracheostomy, and 1 experienced severe right heart failure requiring right-sided VAD.

CONCLUSIONS

This study demonstrates the potential utility of VAD therapies in patients with muscular dystrophy. Further research is needed to further improve outcomes and better determine which patients may benefit most from VAD therapy in terms of survival and quality of life.

Evaluating predicted heart mass in adolescent heart transplantation

BACKGROUND

Predicted Heart Mass (PHM) has emerged as an attractive size matching metric in adult cardiac transplantation. However, since PHM was derived from a healthy adult cohort, its generalizability to the pediatric population is unclear. We hypothesize that PHM can be extended to older adolescents, and potentially broaden the donor pool available to this group.

METHODS

The United Network for Organ Sharing database was retrospectively analyzed for patients aged 13 to 18 undergoing heart transplantation. Recipients were divided into quintiles (Q1-Q5) based on donor-to-recipient predicted heart mass ratios (PHMR). Primary end-point was graft survival at 5 years.

RESULTS

Two thousand sixty-one adolescent heart transplant recipients between January 1994 and September 2019 were retrospectively analyzed. The median PHMR's for each quintile was 0.84 (0.59-0.92), 0.97 (0.92-1.02), 1.08 (1.02-1.14), 1.21 (1.14-1.30), and 1.44 (1.30-2.31). Kaplan-Meier survival curves demonstrated comparable survival across all quintiles of PHMR (p = 0.9). Multivariate Cox regression showed no significant difference in graft failure of the outer quintiles when compared to the middle quintile (Q1: 1.04 HR, p = 0.80; Q2: 1.02 HR, p = 0.89; Q4: 1.19 HR, p = 0.28; Q5: 1.02 HR, p = 0.89). Significant covariates included transplant year (HR: 0.95, p < 0.0001), serum bilirubin (HR: 1.04, p = 0.0004), ECMO at transplantation (HR: 2.85, p < 0.0001), and underlying diagnosis of dilated cardiomyopathy (vs congenital heart disease, HR: 0.66, p = 0.0004).

CONCLUSIONS

Matching by PHM is not associated with survival or risk in adolescent heart transplant recipients. Our results underscore the ongoing need to develop an improved size-matching method in pediatric heart transplantation.

Decreased Risk of Strokes in Children with Ventricular Assist Devices Within ACTION

We sought to characterize strokes in children with ventricular assist devices. Of 407 patients in the ACTION registry (4/1/18-5/3/2021), 45 (11%) experienced 52 strokes (45 ischemic and 7 hemorrhagic). Median time to stroke was 23.5 days and 19/52 (37%) occurred ≤ 10 days. Stroke rate was 0.09 and 0.63 strokes per patient-year for implantable continuous and paracorporeal devices, respectively. Patients with stroke were younger, more likely to have congenital heart disease and have been on extracorporeal membrane oxygenation at time of VAD. Based on these data, ACTION is now focused on decreasing strokes in these higher-risk patients with particular attention to the peri-implant period.

Hemodynamic Predictors of Renal Function After Pediatric Left Ventricular Assist Device Implantation

Although renal function often improves after pediatric left ventricular assist device (LVAD) implantation, recovery is inconsistent. We aimed to identify hemodynamic parameters associated with improved renal function after pediatric LVAD placement. A single-center retrospective cohort study was conducted in patients less than 21 years who underwent LVAD placement between June 2004 and December 2015. The relationship between hemodynamic parameters and estimated glomerular filtration rate (eGFR) was assessed using univariate and multivariate modeling. Among 54 patients, higher preoperative central venous pressure (CVP) was associated with eGFR improvement after implantation (p = 0.012). However, 48 hours postimplantation, an increase in CVP from baseline was associated with eGFR decline over time (p = 0.01). In subgroup analysis, these associations were significant only for those with normal pre-ventricular assist device renal function (p = 0.026). In patients with preexisting renal dysfunction, higher absolute CVP values 48 and 72 hours after implantation predicted better renal outcome (p = 0.005). Our results illustrate a complex relationship between ventricular function, volume status, and renal function. Additionally, they highlight the challenge of using CVP to guide management of renal dysfunction in pediatric heart failure. Better methods for evaluating right heart function and volume status are needed to improve our understanding of how hemodynamics impact renal function in this population.

Significance of pre and post-implant MELD-XI score on survival in children undergoing VAD implantation

BACKGROUND

Derangements in liver and renal function often accompany end-stage heart failure. We sought to assess the utility of an objective risk assessment tool, the Model for End-stage Liver Disease eXcluding INR (MELD-XI), to identify pediatric patients at increased risk for adverse outcomes post-ventricular assist device (VAD) implantation.

METHODS

The Pedimacs database was queried for all pediatric patients who underwent VAD implantation from September 19, 2012 to December 31, 2019. Pre-implant and early (1-week) post-implant MELD-XI scores were used to stratify patients into low, intermediate and high score cohorts. Comparison of pre-implant characteristics and post-implant outcomes were conducted across groups. Multiphase parametric hazard modeling was utilized to identify independent predictors of post-implant mortality.

RESULTS

A total of 742 patients had a calculable MELD-XI score pre-implant. When stratified by MELD-XI scores pre-implant, patients in the high MELD-XI score cohort (score >13.6) had inferior survival and increased bleeding, renal dysfunction and respiratory failure post-implant compared to intermediate and low score cohorts. Risk factors for mortality post-VAD implantation were: increasing MELD-XI scores (HR 1.1 per 1 unit rise), Pedimacs profile 1 (HR 1.6), congenital heart disease (HR 2.3) and being on a percutaneous VAD (HR 2.7). Importantly, MELD-XI score was a better predictor of post-VAD implant mortality than bilirubin or creatinine alone, neither of which were significant in the final model. Patients with increasing or continued high MELD-XI scores early post-implant had the worst survival.

CONCLUSION

The MELD-XI is an easily calculated score that serves as a promising risk assessment tool in identifying children at risk for poor outcomes post VAD implantation.

Compassionate Deactivation of Pediatric Ventricular Assist Devices: A Review of 14 Cases

CONTEXT

Compassionate deactivation (CD) of ventricular assist device (VAD) support is a recognized option for children when the burden of therapy outweighs the benefits.

OBJECTIVES

To describe the prevalence, indications, and outcomes of CD of children supported by VADs at the end of life.

METHODS

Review of cases of CD at our institution between 2011 and 2020. To distinguish CD from other situations where VAD support is discontinued, patients were excluded from the study if they died during resuscitation (including extracorporeal membrane oxygenation), experienced brain or circulatory death prior to deactivation, or experienced a non-survivable brain injury likely to result in imminent death regardless of VAD status.

RESULTS

Of 24 deaths on VAD, 14 (58%) were CD. Median age was 5.7 (interquartile range (IQR) 0.6, 11.6) years; 6 (43%) had congenital heart disease; 4 (29%) were on a device that can be used outside of the hospital. CD occurred after 40 (IQR: 26, 75) days of support; none while active transplant candidates. CD discussions were initiated by the caregiver in 6 (43%) cases, with the remainder initiated by a medical provider. Reasons for CD were multifactorial, including end-organ injury, infection, and stroke. CD occurred with endotracheal extubation and/or discontinuation of inotropes in 12 (86%) cases, and death occurred within 10 (IQR: 4, 23) minutes of CD.

CONCLUSION

CD is the mode of death in more than half of our VAD non-survivors and is pursued for reasons primarily related to noncardiac events. Caregivers and providers both initiate CD discussions. Ventilatory and inotropic support is often withdrawn at time of CD with ensuing death.

Learning networks in pediatric heart failure and transplantation

BACKGROUND

Learning networks have emerged in medicine as a novel organizational structure that contains elements of quality improvement, education, and research with the goal of effecting rapid improvements in clinical care. In this article, the concept of a learning network is defined and highlighted in the field of pediatric heart failure and transplantation.

METHODS

Learning networks are defined, with particular attention paid to the recent creation of the Advanced Cardiac Therapies Improving Outcomes Network (ACTION) for children with heart failure and those being supported with ventricular assist devices (VAD).

RESULTS

The mission, goals, and organizational structure of ACTION are described, and recent initiatives promoted by ACTION are highlighted, such as stroke reduction initiatives, practice harmonization protocols, and use of ACTION data to support the recent US Food and Drug Administration approval of newer VAD for pediatric patients.

CONCLUSIONS

The learning network, exemplified by ACTION, is distinguished from traditional clinical research collaboratives by contributions in research, quality improvement, patient-reported outcomes, and education, and serves as an effective vehicle to drive clinical improvement in the care of children with advanced heart failure.

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.

Stroke in pediatric ventricular assist device patients-a pedimacs registry analysis

BACKGROUND

Cerebralvascular accidents (CVA) are common complications of pediatric ventricular assist devices (VADs). We employed the Pediatric Interagency Registry for Mechanical Circulatory Support (Pedimacs) to investigate rates, risk factors, and outcomes of CVA in pediatric patients supported on VAD.

METHODS

Analysis of Pedimacs (September 2012-June 2019) data to determine rates of all neurologic events and specifically CVA. Risk factors were determined by a multiphase parametric hazard model. Outcomes of patients with CVA were compared with patients without CVA.

RESULTS

We included 662 patients in our analysis. In total, 87 CVA events occurred in 71 patients (10.7%). The proportion of patients with CVA was highest in the paracorporeal pulsatile group (16.9%) followed by the paracorporeal continuous group (10.4%). However, the rate of CVA was lower in the paracorporeal pulsatile group compared to the paracorporeal continuous group (6.4 vs 11.1 events/100 patient months), which reflects differences in support duration. Ascites, higher patient profile groups, and implants within small volume centers were associated with the occurrence of CVA. Our analysis found that the recent era (i.e., June 2017), and intracorporeal continuous implants were protective. Mortality was higher in patients following a CVA diagnosis compared to those without a CVA diagnosis.

CONCLUSIONS

CVA continues to be a problem in pediatric VAD support, though the overall percent is now <11%. Data from the most recent era are encouraging, but CVA is still significantly associated with mortality. Future efforts should focus on pre-implant and early support periods.

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.

Berlin Heart EXCOR and ACTION post-approval surveillance study report

BACKGROUND

The Berlin Heart EXCOR Pediatric (EXCOR) ventricular assist device (VAD) was introduced in North America nearly 2 decades ago. The EXCOR was approved under Humanitarian Device Exemption status in 2011 and received post-market approval (PMA) in 2017 from Food and Drug Administration. Since the initial approval, the field of pediatric mechanical circulatory support has changed, specifically with regard to available devices, anticoagulation strategies, and the types of patients supported. This report summarizes the outcomes of patients supported with EXCOR from the Advanced Cardiac Therapies Improving Outcomes Network (ACTION) registry. These data were part of the PMA surveillance study (PSS) required by the Food and Drug Administration.

METHODS

ACTION is a learning collaborative of over 40 pediatric heart failure programs worldwide, which collects data for all VAD implantations as one of its initiatives. All patients in North America with EXCOR implants reported to ACTION from 2018 to 2020 (n = 72) who had met an outcome were included in the EXCOR PSS group. This was compared with a historical, previously reported Berlin Heart EXCOR study group (Berlin Heart study [BHS] group, n = 320, 2007‒2014).

RESULTS

Patients in the PSS group were younger, were smaller in weight/body surface area, were more likely to have congenital heart disease, and were less likely to receive a bi-VAD than those in the BHS group. Patients in the PSS group were less likely to be in Interagency Registry for Mechanically Assisted Circulatory Support Profile 1 and were supported for a longer duration. The primary anticoagulation therapy for 92% of patients in the PSS group was bivalirudin. Success, defined as being transplanted, being weaned for recovery, or being alive on a device at 180 days after implantation, was 86% in the PSS group compared with 76% in the BHS group. Incidence of stroke was reduced by 44% and the frequency of pump exchange by 40% in the PSS group compared with those in the BHS group. Similarly, all other adverse events, including major bleeding, were reduced in the PSS group.

CONCLUSIONS

The PSS data, collected through ACTION, highlight the improvement in outcomes for patients supported with EXCOR compared with the outcomes in a historical cohort. These findings may be the result of changes in patient care practices over time and collaborative learning.

A coordinated approach to improving pediatric heart transplant waitlist outcomes: A summary of the ACTION November 2019 waitlist outcomes committee meeting

The number of children needing heart transplantation continues to rise. Although improvements in heart failure therapy, particularly durable mechanical support, have reduced waitlist mortality, the number of children who die while waiting for a suitable donor organ remains unacceptably high. Roughly, 13% of children and 25% of infants on the heart transplant waitlist will not survive to transplantation. With this in mind, the Advanced Cardiac Therapies Improving Outcomes Collaborative Learning Network (ACTION), through its Waitlist Outcomes Committee, convened a 2-day symposium in Ann Arbor, Michigan, from 2-3 November 2019, to better understand the factors that contribute to pediatric heart transplant waitlist mortality and to focus future efforts on improving the organ allocation rates for children needing heart transplantation. Using improvement science methodology, the heart failure-transplant trajectory was broken down into six key steps, after which modes of failure and opportunities for improvement at each step were discussed. As a result, several projects aimed at reducing waitlist mortality were initiated.

Palliative Care Engagement for Pediatric Ventricular Assist Device Patients: A Single-Center Experience

Outcomes in pediatric patients with ventricular assist devices (VADs) for advanced heart failure (HF) are improving, but the risk of associated morbidity and mortality remains substantial. Few data exist on the involvement of pediatric palliative care (PPC) in this high-risk patient population. We aimed to characterize the extent of palliative care involvement in the care of patients requiring VAD placement at our institution. Single-center retrospective chart review analyzing all VAD patients at a large pediatric center over a 4 year period. Timing and extent of palliative care subspecialty involvement were analyzed. Between January 2014 and December 2017, 55 HF patients underwent VAD implantation at our institution. Pediatric palliative care utilization steadily increased over consecutive years (2014: <10% of patients, 2015: 20% of patients, 2016: 50% of patients, and 2017: 65% of patients) and occurred in 42% (n = 23) of all patients. Of these, 57% (n = 13) occurred before VAD placement while 43% (n = 10) occurred after implantation. Patients who died during their VAD implant hospitalization (24%, n = 13) were nearly twice as likely to have PPC involvement (62%) as those who reached transplant (38%). Of those who died, patients who had PPC involved in their care were more likely to limit resuscitation efforts before their death. Four patients had advanced directives in place before VAD implant, of which three had PPC consultation before device placement. Three families (5%) refused PPC involvement when offered. Pediatric palliative care utilization is increasing in VAD patients at our institution. Early PPC involvement occurred in the majority of patients and appears to lead to more frequent discussion of goals-of-care and advanced directives.

Treprostinil improves hemodynamics and symptoms in children with mild pulmonary hypertension awaiting heart transplantation

BACKGROUND

Treprostinil, a prostacyclin analog, is a safe and effective therapy for children with PAH; however, the use of this agent in children with mild PVR elevations related to HF, including those with SV congenital heart disease awaiting HT, is understudied. We describe the hemodynamic and symptomatic changes in pediatric patients awaiting HT treated with treprostinil.

METHODS

Single-center retrospective review of all patients was listed for HT who received treprostinil during the listing period. Changes in hemodynamic and functional indices between the baseline catheterization (prior to drug initiation), and prior to HT, and patient outcomes were analyzed.

RESULTS

Among 16/17 (94%) who survived to HT, 8 (50%) were female, and 10 (63%) had SV physiology. The median age at drug initiation was 9 (IQR: 1, 14) years. The median duration of therapy prior to HT was 253 (IQR: 148, 504) days. Treprostinil significantly decreased PVR (3.8 vs 3.1 WU, P = .03), while mLA or mPCW pressure did not change (11 vs 13 mm Hg, P = .9). HF symptoms improved in 9/15 (60%) patients without VAD support prior to drug initiation, including 4/10 (40%) who did not receive a VAD any point while awaiting HT.

CONCLUSIONS

Treprostinil may be used safely in patients with mild PAH awaiting HT, including those with SV disease. PVR falls without substantial increases in mLA/mPCW pressure. HF symptoms improve in some patients.

Review of interactions between high-risk pediatric heart transplant recipients and marginal donors including utilization of risk score models

BACKGROUND

Donor organ acceptance practices vary among pediatric heart transplant professionals. We sought to understand what is known about the interactions between the "high-risk" recipient and the "marginal donor," and how donor risk scores can impact this discussion.

METHODS

A systematic review of published literature on pediatric HTx was undertaken with the assistance of a medical librarian. Two authors independently assessed search results, and papers were reviewed for inclusion.

RESULTS

We found that there are a large number of individual factors, and clusters of factors, that have been used to label individual recipients "high-risk" and individual donors "marginal." The terms "high-risk recipient" and "marginal donor" have been used broadly in the literature making it virtually impossible to make comparisons between publications. In general, the data support that patients who could be easily agreed to be "sicker recipients" are at more risk compared to those who are clearly "healthier," albeit still "sick enough" to need transplantation. Given this variability in the literature, we were unable to define how being a "high-risk" recipient interplays with accepting a "marginal donor." Existing risk scores are described, but none were felt to adequately predict outcomes from factors available at the time of offer acceptance.

CONCLUSIONS

We could not determine what makes a donor "marginal," a recipient "high-risk," or how these factors interplay within the specific recipient-donor pair to determine outcomes. Until there are better risk scores predicting outcomes at the time of organ acceptance, programs should continue to evaluate each organ and recipient individually.

Behavioral economics-A framework for donor organ decision-making in pediatric heart transplantation

The high discard rate of pediatric donor hearts presents a major challenge for children awaiting heart transplantation. Recent literature identifies several factors that contribute to the disparities in pediatric donor heart usage, including regulatory oversight, the absence of guidelines on pediatric donor heart acceptance, and variation among transplant programs. However, a likely additional contributor to this issue are the behavioral factors influencing transplant team decisions in donor offer scenarios, a topic that has not yet been studied in detail. Behavioral economics and decision psychology provide an excellent foundation for investigating decision-making in the pediatric transplant setting, offering key insights into the behavior of transplant professionals. We conducted a systematic review of published literature in pediatric heart transplant related to behavioral economics and the psychology of decision-making. In this review, we draw on paradigms from these two domains in order to examine how existing aspects of the transplant environment, including regulatory oversight, programmatic variation, and allocation systems, may precipitate potential biases surrounding donor offer decisions. Recognizing how human decision behavior influences donor acceptance is a first step toward improving utilization of potentially viable pediatric donor hearts.

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.

Growth stunting in single ventricle patients after heart transplantation

BACKGROUND

Malnutrition is common among children with single ventricle (SV) congenital heart disease (CHD). The impact of heart transplantation (HT) on nutritional status in SV patients is understudied. Our aim was to evaluate anthropometric changes in SV patients after HT, compared with those transplanted for cardiomyopathy (CM).

METHODS

We performed a single-center retrospective chart review of SV and CM patients < 18 years who underwent HT from January 01, 2010 to December 05, 2017. Wasting and stunting were defined as z-scores for weight-for-age or height-for-age ≤-2, respectively. Changes in these indices between HT and 3 years post-HT were analyzed.

RESULTS

Of 86 eligible patients, 28 (33%) had SV CHD and 58 (67%) had CM. Data were available at 3 years post-HT for 57 patients. At transplant, wasting was equally present in SV versus CM patients (7/28, 25% vs. 9/58, 16%, P = .22), which remained true at 3 years post-HT (2/16, 13% vs. 3/41, 7%, P = .61). At transplant, stunting was more common in SV than CM patients (17/28, 61% vs. 8/58, 14%, P < .001). At 3 years post-HT, 6 of 16 (38%) SV patients and 3 of 41 (7%) CM patients remained stunted (P = .01). Among all patients, wasting decreased from transplant to end-point (19% vs. 9%, P = .05), but stunting did not (29% vs. 16%, P = .2), such that wasting and stunting were associated at transplant (P < .001) but not at end-point (P = .17).

CONCLUSIONS

Longitudinal growth remains impaired for several years after HT in SV patients, even when weight gain is achieved, suggesting that some factors contributing to growth impairment persist despite resolution of SV physiology.

Pediatric waitlist and heart transplant outcomes in patients with syndromic anomalies

PURPOSE

We sought to determine whether the presence of a systemic SA with potential complicating factors affects waitlist and post-HT outcomes in pediatric patients.

METHODS

This is a single-center retrospective review of pediatric patients listed for HT between January 1, 2009, and July 1, 2018. Patients were selected based on the presence of any underlying syndromes, which included chromosomal anomalies, skeletal myopathies, connective tissue disorders, mitochondrial disease,and other systemic disorders. Waitlist and post-HT outcomes were compared to those without SA.

RESULTS

A total of 243 patients were listed for HT, of which 21 (9%) patients had associated SA. Of those, 16 (76%) survived to transplant, 3 (14%) died while on the waitlist, 1 (5%) improved and was removed from the waitlist, and 1 (5%) patient is currently listed. Waitlist survival was not different between those with/without an associated syndrome (P = 1.0). Among those who survived to HT, there was no difference in listing days (70 vs 90, P = .8), survival to hospital discharge [14 (93%) vs 150 (95%), P = .6], post-HT intubation days (2 vs 2 days, P = .6), or post-HT hospital length of stay (18 vs 18 days, P = .8). Overall survival during the study period post-HT was not different between groups (P = .8).

CONCLUSION

A SA was present in 9% of pediatric patients wait-listed for HT, but was not associated with an increased waitlist mortality or post-HT hospital morbidity or long-term survival. For several anomalies, HT is safe and feasible.

Healthy Hearts via Live Videoconferencing: An Exercise and Diet Intervention in Pediatric Heart Transplant Recipients

Background

Pediatric heart transplant recipients have high‐risk cardiovascular profiles that can affect their long‐term outcomes; however, promoting exercise and healthy diet has not been a major focus in the field. The objective of this study was to test the feasibility and impact of a supervised exercise and diet intervention delivered via live videoconferencing in this population.

Methods and Results

Patients 8 to 19 years of age at least 1 year post heart transplantation were enrolled. The 12‐ to 16‐week intervention phase included live video–supervised exercise (×3/week) and nutrition (×1/week) sessions. The 12‐ to 16‐week maintenance phase included ×1/week live video–supervised exercise and nutrition sessions and ×2/week self‐directed exercise sessions. Cardiac, vascular, nutritional, and functional health indices were obtained at baseline, after intervention, and after maintenance. Fourteen patients (median age, 15.2; interquartile range, 14.3–16.7 years) at a median of 3.3 (interquartile range, 1.5–9.7) years after heart transplant completed the intervention. Patients attended 89.6±11% of exercise and 88.4±10% of nutrition sessions during the intervention and 93.4±11% of exercise and 92.3±11% of nutrition sessions during maintenance. After intervention, body mass index percentile (median, −27%; P=0.02), endothelial function (median, +0.29; P=0.04), maximum oxygen consumption (median, +2 mL/kg per minute; P=0.002). Functional Movement Screening total score (median, +2.5; P=0.002) and daily consumption of saturated fat (median, −6 g; P=0.02) improved significantly. After maintenance, improvements in maximum oxygen consumption (median, +3.2 mL/kg per minute; P=0.02) and Functional Movement Screening total score (median, +5; P=0.002) were sustained.

Conclusions

In pediatric heart transplant recipients, a live video–supervised exercise and diet intervention is feasible. Our results demonstrate excellent adherence with significant improvements in cardiovascular and functional health.

Clinical Trial Registration

URL: http://www.clinicaltrials.gov. Unique identifier: NCT02519946.

Collaboration and new data in ACTION: a learning health care system to improve pediatric heart failure and ventricular assist device outcomes

Outcomes in pediatric heart failure and ventricular assist devices (VADs) remain suboptimal. Given the complexity and limited numbers, centers cannot be expected to acquire mastery and generalizable knowledge independently. Recognizing this problem, the community has formed Advanced Cardiac Therapies Improving Outcomes Network (ACTION), a collaborative learning health care system committed to unrelenting collaboration and continuous learning to improve critical outcomes in pediatric heart failure. ACTION is inclusive of all interested parties and believes the fastest and most effective way to make progress is through working together. ACTION's approaches to collaboration and data sharing will be highlighted.

Evaluation and Management of the Child and Adult With Fontan Circulation: A Scientific Statement From the American Heart Association

It has been 50 years since Francis Fontan pioneered the operation that today bears his name. Initially designed for patients with tricuspid atresia, this procedure is now offered for a vast array of congenital cardiac lesions when a circulation with 2 ventricles cannot be achieved. As a result of technical advances and improvements in patient selection and perioperative management, survival has steadily increased, and it is estimated that patients operated on today may hope for a 30-year survival of >80%. Up to 70 000 patients may be alive worldwide today with Fontan circulation, and this population is expected to double in the next 20 years. In the absence of a subpulmonary ventricle, Fontan circulation is characterized by chronically elevated systemic venous pressures and decreased cardiac output. The addition of this acquired abnormal circulation to innate abnormalities associated with single-ventricle congenital heart disease exposes these patients to a variety of complications. Circulatory failure, ventricular dysfunction, atrioventricular valve regurgitation, arrhythmia, protein-losing enteropathy, and plastic bronchitis are potential complications of the Fontan circulation. Abnormalities in body composition, bone structure, and growth have been detected. Liver fibrosis and renal dysfunction are common and may progress over time. Cognitive, neuropsychological, and behavioral deficits are highly prevalent. As a testimony to the success of the current strategy of care, the proportion of adults with Fontan circulation is increasing. Healthcare providers are ill-prepared to tackle these challenges, as well as specific needs such as contraception and pregnancy in female patients. The role of therapies such as cardiovascular drugs to prevent and treat complications, heart transplantation, and mechanical circulatory support remains undetermined. There is a clear need for consensus on how best to follow up patients with Fontan circulation and to treat their complications. This American Heart Association statement summarizes the current state of knowledge on the Fontan circulation and its consequences. A proposed surveillance testing toolkit provides recommendations for a range of acceptable approaches to follow-up care for the patient with Fontan circulation. Gaps in knowledge and areas for future focus of investigation are highlighted, with the objective of laying the groundwork for creating a normal quality and duration of life for these unique individuals.

A Quality Bundle to Support High-Risk Pediatric Ventricular Assist Device Implantation

Pediatric ventricular assist device (VAD) implantation outcomes are increasingly promising for children with dilated cardiomyopathy and advanced decompensated heart failure (ADHF). VAD placement in patients with clinical features such as complex congenital cardiac anatomy, small body size, or major comorbidities remains problematic. These comorbidities have been traditionally prohibitive for VAD consideration leaving these children as a treatment-orphaned population. Here we describe the quality bundle surrounding these patients with ADHF considered high risk for VAD implantation at our institution. Over a 7-year period, a quality bundle aimed at the peri-operative care for children with high-risk features undergoing VAD implantation was incrementally implemented at a tertiary children's hospital. Patients were considered high risk if they were neonates (< 30 days), had single-ventricle physiology, non-dilated cardiomyopathy, biventricular dysfunction, or significant comorbidities. The quality improvement bundle evolved to include (1) structured team-based peri-operative evaluation, (2) weekly VAD rounds addressing post-operative device performance, (3) standardized anticoagulation strategies, and (4) a multidisciplinary system for management challenges. These measures aimed to improve communication, standardize management, allow for ongoing process improvement, and incorporate principles of a high-reliability organization. Between January 2010 and December 2017, 98 patients underwent VAD implantation, 48 (49%) of which had high-risk comorbidities and a resultant cohort survival-to-transplant rate of 65%. We report on the evolution of a quality improvement program to expand the scope of VAD implantation to patients with high-risk clinical profiles. This quality bundle can serve as a template for future large-scale collaborations to improve outcomes in these treatment-orphaned subgroups.

Compassionate deactivation of ventricular assist devices in children: A survey of pediatric ventricular assist device clinicians' perspectives and practices

OBJECTIVES

This study's objective was to investigate compassionate ventricular assist device deactivation (VADdeact) in children from the perspective of the pediatric heart failure provider.

BACKGROUND

Pediatric VAD use is a standard therapy for advanced heart failure. Serious adverse events may affect relative benefit of continued support, leading to consideration of VADdeact. Perspectives and practices regarding VADdeact have been studied in adults but not in children.

METHODS

A web-based anonymous survey of clinicians for pediatric VAD patients (<18 years) was sent to list-serves for the ISHLT Pediatric Council, the International Consortium of Circulatory Assist Clinicians Pediatric Taskforce, and the Pediatric Cardiac Intensivist Society.

RESULTS

A total of 106 respondents met inclusion criteria of caring for pediatric VAD patients. Annual VAD volume per clinician ranged from <4 (33%) to >9 (20%). Seventy percent of respondents had performed VADdeact of a child. Response varied to VADdeact requests by parent or patient and was influenced by professional degree and region of practice. Except for the scenario of intractable suffering, no consensus on VADdeact appropriateness was reported. Age of child thought capable of making informed requests for VADdeact varied by subspecialty. The majority of respondents (62%) do not feel fully informed of relevant legal issues; 84% reported that professional society supported guidelines for VADdeact in children had utility.

CONCLUSION

There is limited consensus regarding indications for VADdeact in children reported by pediatric VAD provider survey respondents. Knowledge gaps related to legal issues are evident; therefore, professional guidelines and educational resources related to pediatric VADdeact are needed.

Short-term outcomes of en bloc combined heart and liver transplantation in the failing Fontan

Patients with failing Fontan physiology and liver cirrhosis are being considered for combined heart and liver transplantation. We performed a retrospective review of our experience with en bloc combined heart and liver transplantation in Fontan patients > 10 years old from 2006 to 18 per Institutional Review Board approval. Six females and 3 males (median age 20.7, range 14.2-41.3 years) underwent en bloc combined heart and liver transplantation. Indications for heart transplant included ventricular dysfunction, atrioventricular valve regurgitation, arrhythmia, and/or lymphatic abnormalities. Indication for liver transplant included portal hypertension and cirrhosis. Median Fontan/single ventricular end-diastolic pressure was 18/12 mm Hg, respectively. Median Model for End-Stage Liver Disease excluding International Normalized Ratio score was 10 (7-26), eight patients had a varices, ascites, splenomegaly, thrombocytopenia score of ≥ 2, and all patients had cirrhosis. Median cardiopulmonary bypass and donor ischemic times were 262 (178-307) and 287 (227-396) minutes, respectively. Median intensive care and hospital stay were 19 (5-96) and 29 (13-197) days, respectively. Survival was 100%, and rejection was 0% at 30 days and 1 year post-transplant. En bloc combined heart and liver transplantation is an acceptable treatment in the failing Fontan patient with liver cirrhosis.

Impact of ventricular assist device implantation on the nutritional status of children awaiting heart transplantation

BACKGROUND

Malnutrition is common in pediatric heart failure and is associated with mortality. The effect of VAD support on malnutrition in children is unknown. We sought to compare the prevalence and severity of malnutrition at HT in children on VAD support vs OMT to inform decisions regarding support strategies.

METHODS

Retrospective chart review involving all patients <18 years who underwent HT at Stanford between 1/1/2011 and 3/1/2018. Malnutrition diagnosis and severity were defined by ASPEN guidelines using the lowest age-adjusted z-score for weight (WAZ), height (HAZ), and BMI (BMIZ) when the patient was euvolemic. Changes in z-scores from baseline to HT and across groups were analyzed.

RESULTS

A total of 104 patients (52 in each group) were included. Among all patients, WAZ (-0.9 vs 0.3, P < 0.001) and BMIZ (0 vs 0.6, P < 0.001) improved while HAZ (-0.9 vs -0.9, P = 0.4) did not. Compared to children on OMT, children on VAD experienced greater increases in WAZ (0.8 vs 0.3, P < 0.001) and BMIZ (0.7 vs 0.2, P < 0.003) at HT. The prevalence of moderate-to-severe malnutrition decreased in VAD patients (40% to 19%, P < 0.001) and increased in OMT patients (37% to 46%, P < 0.001), leading to a lower prevalence of moderate-to-severe malnutrition at HT (19% vs 46%, P = 0.003).

CONCLUSIONS

Malnutrition is common in pediatric HT candidates. Compared to children on OMT, children on VAD support had greater improvement in nutritional status while awaiting HT, and a lower prevalence of malnutrition at HT.

Heart transplantation in two adolescents with Danon disease

Danon disease (DD) is an X-linked dominant disorder caused by a mutation in the lysosomal-associated membrane protein-2 (LAMP-2) gene coding for the LAMP-2 protein. We report two cases of successful heart transplantation (HT) in adolescent brothers with DD, including one who was bridged to HT for 34 days with a HeartWare left ventricular assist device. In both patients, the post-transplant course was complicated by profound skeletal muscle weakness that resolved with corticosteroid withdrawal. These cases highlight that both HT and ventricular assist device support are feasible in patients with DD. Corticosteroid use may exacerbate skeletal myopathy, and therefore, steroid minimization may be warranted whenever possible.