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.

Implications of Left Ventricular Dysfunction at Presentation for Infants with Coarctation of the Aorta.

Infants with aortic coarctation may present with left ventricular (LV) dysfunction which may complicate the postoperative course and lead to increased healthcare costs. We aimed to define the prevalence of moderate to severe left ventricular (LV) systolic dysfunction, evaluate time to recovery, and compare health care costs. Single-center retrospective cohort study at a tertiary care hospital was conducted. Infants < 6 months old at diagnosis with aortic coarctation were identified using surgical codes for coarctation repair between January 2010 and May 2018. Moderate to severe dysfunction was defined as ejection fraction (EF) < 40%. Of 160 infants studied, 18 (11%) had moderate to severe LV dysfunction at presentation. Compared to those with better LV function, infants with moderate to severe LV dysfunction were older at presentation (12 vs. 6 days, p = 0.004), had more postoperative cardiac intensive care unit (ICU) days (5 vs. 3, p < 0.001), and more ventilator days (3.5 vs. 1, p < 0.001). The median time to normal LV EF (≥ 55%) was 6 days postoperatively (range 1-230 days). Infants presenting with moderate to severe LV dysfunction had higher index hospitalization costs ($90,560 vs. $59,968, p = 0.02), but no difference in cost of medical follow-up for the first year following discharge ($3,078 vs. $2,568, p = 0.46). In the current era, > 10% of infants with coarctation present with moderate to severe LV dysfunction that typically recovers. Those with moderate to severe dysfunction had longer duration of mechanical ventilation and postoperative cardiac ICU stays, likely driving higher costs of index hospitalization.

Cardiac transplantation in children with Noonan syndrome.

NS and related RAS/MAPK pathway (RASopathy) disorders are the leading genetic cause of HCM presenting in infancy. HCM is a major cause of morbidity and mortality in children with Noonan spectrum disorders, especially in the first year of life. Previously, there have been only isolated reports of heart transplantation as a treatment for heart failure in NS. We report on 18 patients with NS disorders who underwent heart transplantation at seven US pediatric heart transplant centers. All patients carried a NS diagnosis: 15 were diagnosed with NS and three with NSML. Sixteen of eighteen patients had comprehensive molecular genetic testing for RAS pathway mutations, with 15 having confirmed pathogenic mutations in PTPN11, RAF1, and RIT1 genes. Medical aspects of transplantation are reported as well as NS-specific medical issues. Twelve of eighteen patients described in this series were surviving at the time of data collection. Three patients died following transplantation prior to discharge from the hospital, and another three died post-discharge. Heart transplantation in NS may be a more frequent occurrence than is evident from the literature or registry data. A mortality rate of 33% is consistent with previous reports of patients with HCM transplanted in infancy and early childhood. Specific considerations may be important in evaluation of this population for heart transplant, including a potentially increased risk for malignancies as well as lymphatic, bleeding, and coagulopathy complications.

Haemodynamic profiles of children with end-stage heart failure.

AIMS: To evaluate associations between haemodynamic profiles and symptoms, end-organ function and outcome in children listed for heart transplantation. METHODS AND RESULTS: Children <18 years listed for heart transplant between 1993 and 2013 with cardiac catheterization data [pulmonary capillary wedge pressure (PCWP), right atrial pressure (RAP), and cardiac index (CI)] in the Pediatric Heart Transplant Study database were included. Outcomes were New York Heart Association (NYHA)/Ross classification, renal and hepatic dysfunction, and death or clinical deterioration while on waitlist. Among 1059 children analysed, median age was 6.9 years and 46% had dilated cardiomyopathy. Overall, 58% had congestion (PCWP >15 mmHg), 28% had severe congestion (PCWP >22 mmHg), and 22% low cardiac output (CI < 2.2 L/min/m2). Twenty-one per cent met the primary outcome of death (9%) or clinical deterioration (12%). In multivariable analysis, worse NYHA/Ross classification was associated with increased PCWP [odds ratio (OR) 1.03, 95% confidence interval (95% CI) 1.01-1.07, P = 0.01], renal dysfunction with increased RAP (OR 1.04, 95% CI 1.01-1.08, P = 0.007), and hepatic dysfunction with both increased PCWP (OR 1.03, 95% CI 1.01-1.06, P < 0.001) and increased RAP (OR 1.09, 95% CI 1.06-1.12, P < 0.001). There were no associations with low output. Death or clinical deterioration was associated with severe congestion (OR 1.6, 95% CI 1.2-2.2, P = 0.002), but not with CI alone. However, children with both low output and severe congestion were at highest risk (OR 1.9, 95% CI 1.1-3.5, P = 0.03). CONCLUSION: Congestion is more common than low cardiac output in children with end-stage heart failure and correlates with NYHA/Ross classification and end-organ dysfunction. Children with both congestion and low output have the highest risk of death or clinical deterioration.

Recovery From Acute Kidney Injury and CKD Following Heart Transplantation in Children, Adolescents, and Young Adults: A Retrospective Cohort Study.

BACKGROUND: Acute kidney injury (AKI) is common in children following surgery for congenital heart disease and has been associated with poor long-term kidney outcomes. Children undergoing heart transplantation may be at increased risk for the development of both AKI and chronic kidney disease (CKD). This study examines AKI rates in children, adolescents, and young adults after heart transplantation and analyzes the relationship between AKI and CKD in this population. STUDY DESIGN: Retrospective cohort study. SETTING & PARTICIPANTS: 88 young patients who underwent heart transplantation at Lucile Packard Children's Hospital, Stanford, CA, September 1, 2007, to November 30, 2013. PREDICTOR: The primary independent variable was AKI within the first 7 postoperative days, ascertained according to the KDIGO (Kidney Disease: Improving Global Outcomes) creatinine criteria (increase in serum creatinine ≥ 1.5 times baseline within 7 days). OUTCOMES: Recovery from AKI at 3 months, ascertained as serum creatinine level < 1.5 times baseline; and development of CKD at 6 and 12 months, ascertained as estimated glomerular filtration rate < 60mL/min/1.73m(2) for more than 3 months. RESULTS: 63 (72%) patients developed AKI; 57% had moderate (stage 2 or severe stage 3) disease. Recovery occurred in 39 of 63 (62%), 50% for stage 2 or 3 versus 78% for stage 1 (P=0.04). At 6 and 12 months, 3 of 82 (4%) and 4 of 76 (5%) developed CKD, respectively. At both time points, CKD was more common in those without recovery (3/22 [14%] vs 0/38 (0%); P=0.04, and 3/17 (18%) vs (0/34) 0%; P=0.03, respectively). LIMITATIONS: Retrospective design, small sample size, and single-center nature of the study. CONCLUSIONS: AKI is common after heart transplantation in children, adolescents, and young adults. Nonrecovery from AKI is more common in patients with more severe AKI and is associated with the development of CKD during the first year.

Group visits in the pediatric heart transplant outpatient clinic.

The "GVM" has emerged as an alternative to traditional individualized appointments in the ambulatory care setting. We hypothesized that group visits could successfully be utilized in a PHtx clinic. Seven patients, ages 1-18 yr old, and their families participated in a total of 11 group visits in lieu of individualized appointments. Patients were divided into two groups based on whether they were greater or less than one yr post-transplant. Patient/provider satisfaction, medication adherence, and content retention were ascertained via questionnaires and free-response tests. Total clinic throughput time, including per-patient clinic utilization time, was compared to historical data. Six of seven patients completed the study with one dropout. Overall satisfaction ratings were 3.98 of 4 with all patients reporting that they would "strongly recommend" group visits to others. Health information retention tests demonstrated improvement between pre- and post-tests in eight of nine (89%) of the group visits. Overall clinic utilization decreased by nearly 50% while providing 70 min of face-to-face time with the provider. Medication adherence neared 100% for all patients. The GVM can be successfully applied to the PHtx population with high patient and provider satisfaction, more face-to-face time, excellent content retention, and greatly improved clinic efficiency.

QTc Prolongation in Acute Pediatric Migraine.

OBJECTIVES: Migraine headache is common in pediatrics and is frequently assessed in emergency departments. Altered cardiac conduction, including prolongation of the QTc interval on electrocardiogram, has been observed in adults during migraine headache and resolves interictally. Prolonged QTc is associated with life-threatening arrhythmia, and many acute and prophylactic therapies for migraine can further prolong the QTc interval. It is the objective of this prospective cohort study to examine whether the QTc interval prolongs significantly during periods of acute migraine headache in children. METHODS: Patients ages 6 to 17 years presenting to the emergency department with acute migraine headache were recruited prospectively. Exclusion criteria included the use of QTc-prolonging medications and medical illnesses, including cardiovascular abnormalities, infection, or head injury. Paired, one-tailed Student t tests compared QTc intervals with and without headache and evaluated for QTc prolongation of 30 ms or longer during headache. RESULTS: Thirteen patients with migraine (mean age, 11.6 ± 2.6 years) were evaluated. Mean QTc interval during headache was significantly longer than the QTc interval in the absence of headache (437.9 ± 27.7 ms compared with 419.3 ± 29.9 ms; p = 0.04). Three patients (23%) had unequivocal prolongation of the QTc (>460 ms) during the migraine, two of which normalized with headache resolution. The mean increase in QTc during headache did not reach or exceed 30 ms (p = 0.86) CONCLUSIONS: This study is the first to illustrate a connection between QTc prolongation and acute migraine headache in children. If confirmed in future studies, children should be monitored for QTc prolongation during the acute treatment of migraine in the emergency department when using medications that can lengthen the QTc interval.

HLA desensitization with bortezomib in a highly sensitized pediatric patient.

The proteasome inhibitor bortezomib has been used with variable success in the treatment of AMR following heart transplant. There is limited experience with this agent as a pretransplant desensitizing therapy. We report a case of successful HLA desensitization with a bortezomib-based protocol prior to successful heart transplantation. A nine-yr-old boy with dilated cardiomyopathy, not initially sensitized to HLA (cPRA of zero), required three days of ECMO, followed by implantation of a Heartmate II LVAD. Within six wk, the patient developed de novo class I IgG and C1q complement-fixing HLA antibodies with a cPRA of 100%. Two doses of IVIG (2 g/kg) failed to reduce antibody levels, although two courses of a novel desensitization protocol consisting of rituximab (375 mg/m(2) ), bortezomib (1.3 mg/m(2)  × 5 doses), and plasmapheresis reduced his cPRA to 0% and 87% by the C1q and IgG assays, respectively. He underwent heart transplantation nearly two months later. The patient is now >one yr post-transplant, is free of both AMR and ACR, and has no detectable donor-specific antibodies by IgG or C1q. Proteasome inhibition with bortezomib and plasmapheresis may be an effective therapy for HLA desensitization pretransplant.

Optimizing care of adults with congenital heart disease in a pediatric cardiovascular ICU using electronic clinical decision support*.

OBJECTIVES: The optimal location for postoperative cardiac care of adults with congenital heart disease is controversial. Some congenital heart surgeons operate on these adults in children's hospitals with postoperative care provided by pediatric critical care teams who may be unfamiliar with adult national performance measures. This study tested the hypothesis that Clinical Decision Support tools integrated into the clinical workflow would facilitate improved compliance with The Joint Commission Surgical Care Improvement Project performance measures in adults recovering from cardiac surgery in a children's hospital. DESIGN: Retrospective chart review comparing compliance pre- and post-Clinical Decision Support intervention for Surgical Care Improvement Project measures addressed in the critical care unit: appropriate cessation of prophylactic antibiotics; controlled blood glucose; urinary catheter removal; and reinitiation of preoperative ß-blocker when indicated. SETTING: Cardiovascular ICU in a quaternary care freestanding children's hospital. PATIENTS: The cohort included 114 adults 18-70 years old recovering from cardiac surgery in our pediatric cardiovascular ICU. INTERVENTIONS: Clinical Decision Support tools including data-triggered alerts, smart documentation forms, and order sets with conditional logic were integrated into the workflow. MEASUREMENTS AND MAIN RESULTS: Compliance with antibiotic discontinuation was 100% pre- and postintervention. Compliance rates improved for glucose control (p = 0.007) and urinary catheter removal (p = 0.05). Documentation of ß-blocker therapy (nonexistent preintervention) was 100% postintervention. Composite compliance for all measures increased from 53% to 84% (p = 0.002). There were no complications related to institution of the Surgical Care Improvement Project measures. There was no in-hospital mortality. CONCLUSIONS: Compliance with the national adult postoperative performance measures can be excellent in a children's hospital with the help of Clinical Decision Support tools. This represents an important step toward providing high-quality care to a growing population of adults with congenital heart disease who may receive care in a pediatric center.

Supine cycling in pediatric exercise testing: disparity in performance measures.

Supine cycling may be an important alternative modality for exercise testing. Subtle differences in supine and upright exercise physiology have been suggested but not fully explored in the pediatric population. The aim of this study was to compare peak and submaximal metabolic data in the upright and supine exercise positions. Healthy children (N = 100) performed cardiopulmonary exercise tests using supine and upright cycle ergometry. Recruitment was governed by grant funding and not based on sample size calculations. Subjects exercised to exhaustion. Paired Student's t-tests were used to compare upright and supine data; simple linear regression analyses examined correlations between the two modalities. Peak heart rate was similar in both testing positions. Although peak oxygen uptake (peak VO2), oxygen uptake at anaerobic threshold (VO2@AT), VO2 when the respiratory exchange ratio is consistently at or above 1.0 (VO2@RER1.0), and the oxygen uptake efficiency slope were significantly higher in the upright position, no difference was considered of practical significance when applying Cohen's effect size criteria. Therefore, it may be reasonable for pediatric exercise laboratories to use established normative data and predictions for upright cycling position and apply them to metabolic measures obtained in supine exercise testing. Supine cycling with submaximal parameters may allow objective assessment of exercise capacity in children who undergo exercise echocardiography or cannot perform upright exercise testing.

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.

Attitudes & practices surrounding pregnancy post heart transplant among pediatric providers.

BACKGROUND: Many pediatric heart transplant (HT) recipients reach adulthood and may be interested in family planning; there is little data regarding safety of pregnancy post HT and clinicians' opinions differ. Pediatric HT clinicians are instrumental in early counseling. Thus, a better understanding of pediatric HT clinicians' practices regarding family planning and how well aligned these practices are with adult transplant centers is essential. METHODS: We conducted a confidential, web-based survey of pediatric HT clinicians in fall 2021. We summarized and compared answers using Fisher's exact test. RESULTS: The survey was sent to 53 United States-based HT directors and to the International Society for Heart and Lung Transplantation and Pediatric Heart Transplant Society list serves. There were 69 respondents. The majority (77%) of respondents felt pregnancy was feasible in selected or all female HT recipients. Ten respondents reported that their institution had an established policy regarding pregnancy post HT. A majority (77%) of HT clinicians would either use a shared care model or recommend transition to their adult institution if pregnancy occurred, though 74% of respondents were either unaware of their corresponding adult institution's policy (62%) or had a counterpart adult program with a policy against pregnancy post HT (12%). CONCLUSIONS: While many clinicians feel pregnancy is feasible in pediatric HT recipients, there remains significant practice variation. Few pediatric programs have a policy regarding pregnancy post HT. Future efforts to provide consistent messaging between adult and pediatric HT programs regarding the feasibility and care of post HT pregnancy are warranted.

The evolving approach to paediatric myocarditis: a review of the current literature.

Paediatric myocarditis remains challenging from the perspectives of diagnosis and management. Multiple aetiologies exist and the majority of cases appear to be related to viral illnesses. Enteroviruses are believed to be the most common cause, although cases related to adenovirus may be more frequent than suspected. The clinical presentation is extremely varied, ranging from asymptomatic to sudden unexpected death. A high index of suspicion is crucial. There is emerging evidence to support investigations such as serum N-terminal B-type natriuretic peptide levels, as well as cardiac magnetic resonance imaging as adjuncts to the clinical diagnosis. In the future, these may reduce the necessity for invasive methods, such as endomyocardial biopsy, which remain the gold standard. Management generally includes supportive care, consisting of cardiac failure medical management, with the potential for mechanical support and cardiac transplantation. Treatments aimed at immunosuppression remain controversial. The paediatric literature is extremely limited with no conclusive evidence to support or refute these strategies. This article summarises the current literature regarding aetiology, clinical presentation, diagnosis, and management of myocarditis in paediatric patients.

Time in Therapeutic Range for Bivalirudin Among Pediatric Ventricular Assist Device Recipients.

Given the adverse event rates involving bleeding and thrombosis among children on ventricular assist devices (VADs), anticoagulant management has become a focal point for quality improvement and innovation. There may be advantages to using direct thrombin inhibitors, such as bivalirudin, though this has not been fully explored. As the percent time in therapeutic range (%TTR) for anticoagulants is classically associated with improved clinical outcomes, we evaluated the %TTR for bivalirudin among pediatric VAD recipients. Using a modification of the Rosendaal method, %TTR was calculated using activated partial thromboplastin time measurements for 11 VAD recipients in the early postoperative period (postoperative days 0-14) and for the duration of VAD support. In the initial 2 weeks after VAD implant, mean %TTR was 68.7 (±13.0). During the entire support course, the mean %TTR improved to 79.6 (±11.0). There was an era effect with improving %TTR in the latter half of the study period. We report very good %TTR for bivalirudin both in the first 2 weeks post implant and this improved over the duration of support. Because %TTR reflects the degree of safety and efficacy in chronic anticoagulation, this relatively high %TTR among a diverse, often critically ill cohort suggests that bivalirudin may be a promising agent. Although this study was underpowered to comprehensively evaluate adverse events on bivalirudin, this represents an important next step for larger scale study.

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.

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.

Marked Practice Variation in Antithrombotic Care with the Berlin Heart EXCOR Pediatric Ventricular Assist Device.

Management of antithrombotic therapy (ATT) for pediatric ventricular assist devices is challenging, and the Berlin EXCOR remains the only Food and Drug Administration (FDA)-approved option. Among those on the EXCOR, 28% have neurologic complications and major bleeding occurs in 50%. The Edmonton Protocol was developed to guide ATT, but the adverse event rate remains high, leading most centers to make modifications. The objective of this study is to characterize antithrombotic practice variation among North American pediatric ventricular assist device programs, in order to guide future research. In this descriptive cross-sectional study, a survey assessing antithrombotic (AT) practices was distributed by Berlin Heart Inc. to centers that implanted ≥1 EXCOR between January 2012 and January 2016. Practices were compared at high- versus low-volume centers. High volume was defined as ≥14 implants in this period. Seventeen of 38 centers (44.7%) participated; 4 were high volume. At half of all centers (9/17), ≤2 clinicians managed all AT decisions. Although 47.1% (8/17) followed the protocol "extremely/very closely," only 5.9% (1/17) felt it to be "very effective." Most centers (10/15; 66.7%) deviated in ≥2 protocol aspects. Over half modified either recommended antiplatelet agents (5/15) or anticoagulants (4/15). Adjunct medication use was highly variable. Most (11/17; 64.7%) deviated from protocol in either timing or type of AT lab monitoring. Despite widespread use of Thromboelastography (TEG)/Platelet Mapping (PM), concerns of inaccuracy were common. Most high-volume centers (3/4; 75%) abandoned TEG/PM as a primary tool. These practice variation analyses have identified areas in ATT that are amenable to care standardization and further research. Systematic study of optimal AT medication dosing and monitoring is needed.

Outpatient Outcomes of Pediatric Patients with Left Ventricular Assist Devices.

Outpatient experience of children supported with continuous-flow ventricular assist devices (CF-VAD) is limited. We reviewed our experience with children discharged with CF-VAD support. All pediatric patients <18 years old with CF-VADs implanted at our institution were included. Discharge criteria included a stable medication regimen, completion of a VAD education program and standardized rehabilitation plan, and presence of a caregiver. Hospital readmissions (excluding scheduled admissions) were reviewed. Adverse events were defined by Interagency Registry for Mechanically Assisted Circulatory Support (INTERMACS) criteria. Of 17 patients with CF-VADs, 8 (47%) were discharged from the hospital (1 HeartWare ventricular assist device (Heartware Inc., Framingham, MA), 7 HeartMate II (Thoratec Corp, Pleasanton, CA)). Median age was 15.3 (range 9.6-17.1) years and weight was 50.6 (33.6-141) kg. Device strategies were destination therapy (DT; n = 4) and bridge to transplant (n = 4). Patients spent a median 49 (26-107) days hospitalized postimplant and had 2 (1-5) hospital readmissions. Total support duration was 3,154 patient-days, with 2,413 as outpatient. Most frequent adverse events were device malfunction and arrhythmias. There was one death because of pump thrombosis and no bleeding or stroke events. Overall adverse event rate was 15.22 per 100 patient-months. Early experience suggests that children with CF-VADs can be safely discharged. Device malfunction and arrhythmia were the most common adverse events but were recognized quickly with structured outpatient surveillance.

Electrocardiographic repolarization abnormalities and increased risk of life-threatening arrhythmias in children with dilated cardiomyopathy.

BACKGROUND: Life-threatening arrhythmia events (LTEs) occur in ~5% of children with dilated cardiomyopathy (DCM). While prolonged QRS duration has been shown to be associated with LTEs, electrocardiographic (ECG) repolarization findings have not been examined. OBJECTIVE: We sought to determine the associations between ECG repolarization abnormalities and LTEs in children with DCM. METHODS: A single-center retrospective review of children with DCM was performed. LTEs were defined as documented ventricular tachycardia or fibrillation requiring medical intervention. Three pediatric cardiologists, blinded to clinical events, evaluated ECGs obtained at the time of initial referral. Kaplan-Meier survival and Cox proportional hazards analyses were used to evaluate time to LTEs. RESULTS: A total of 137 patients (mean age 7.8 ± 6.7 years; 75(55%) male patients) with DCM (mean ejection fraction 35% ± 16%) were included; 67 patients (49%) had a corrected JT (JTc) interval of ≥340 ms, 72 (53%) had a corrected QT (QTc) interval of ≥450 ms, and 41 (30%) had abnormal T waves. LTEs occurred in 15 patients at a median of 12 months (interquartile range 3-36 months) after the initial ECG. Patients with LTEs had a longer JTc interval (371 ± 77 ms vs 342 ± 41 ms; P = .02) and a longer QTc interval (488 ± 96 ms vs 453 ± 44 ms; P = .01). In survival analysis, a JTc interval of ≥390 ms (hazard ratio [HR] 4.07; 95% confidence interval [CI] 1.12-14.83; P = .03), a QTc interval of ≥510 ms (HR 6.95; 95% CI 1.53-31.49; P = .01), abnormal T-wave inversion (HR 11.62; 95% CI 2.75-49.00; P = .001), and ST-segment depression (HR 6.91; 95% CI 1.25-38.27; P = .03) were associated with an increased risk of LTEs, even after adjusting for QRS duration and amiodarone use. CONCLUSION: Repolarization abnormalities are common in children with DCM. Certain ECG repolarization abnormalities, such as significantly prolonged JTc and QTc intervals, may be useful in identifying patients at risk of LTEs.

Impact of ventricular assist device placement on longitudinal renal function in children with end-stage heart failure.

BACKGROUND: Although ventricular assist devices (VADs) restore hemodynamics in those with heart failure, reversibility of end-organ dysfunction with VAD support is not well characterized. Renal function often improves in adults after VAD placement, but this has not been comprehensively explored in children. METHODS: Sixty-three children on VAD support were studied. Acute kidney injury (AKI) was defined by Kidney Disease: Improving Global Outcomes criteria. Estimated glomerular filtration rate (eGFR) was determined by the Schwartz method. Generalized linear mixed-effects models compared the pre-VAD and post-VAD eGFR for the cohort and sub-groups with and without pre-VAD renal dysfunction (pre-VAD eGFR < 90 ml/min/1.73 m(2)). RESULTS: The pre-VAD eGFR across the cohort was 84.0 ml/min/1.73 m(2) (interquartile range [IQR] 62.3-122.7), and 55.6% (34 of 63) had pre-VAD renal dysfunction. AKI affected 60.3% (38 of 63), with similar rates in those with and without pre-existing renal dysfunction. Within the cohort, the nadir eGFR occurred 1 day post-operatively (62.9 ml/min/1.73 m(2); IQR, 51.2-88.9 ml/min/1.73 m(2); p < 0.001). By Day 5, however, the eGFR exceeded the baseline (99.0 ml/min/1.73 m(2); IQR, 59.3-146.7 ml/min/1.73 m(2); p = 0.03) and remained significantly higher through the first post-operative week. After adjusting for age, gender, and AKI, the eGFR continued to increase throughout the entire 180-day study period (ß = 0.0025; 95% confidence interval, 0.0015-0.0036; p < 0.001). Patients with pre-VAD renal dysfunction experienced the greatest improvement in the eGFR (ß = 0.0051 vs ß = 0.0013, p < 0.001). CONCLUSIONS: Renal dysfunction is prevalent in children with heart failure undergoing VAD placement. Although peri-operative AKI is common, renal function improves substantially in the first post-operative week and for months thereafter. This is particularly pronounced in those with pre-VAD renal impairment, suggesting that VADs may facilitate recovery and maintenance of kidney function in children with advanced heart failure.