Serum troponin (Tn) is often elevated in viral myocarditis; however, its prognostic significance is unknown. We tested the hypothesis that abnormal serum Tn is associated with mortality in children hospitalized with myocarditis. We retrospectively studied data from six large children's hospitals participating in the Pediatric Health Information System Plus (PHIS+) database. Analysis was performed on patients hospitalized with viral myocarditis between 2007 and 2013, in whom at least one Tn was recorded within 72 h of admission. Abnormal baseline Tn was defined as any value outside the upper limit of normal within the first 72 h. Primary outcome was mortality. Secondary outcomes included mechanical support, defined as use of extracorporeal membrane oxygenation (ECMO) or a ventricular assist device (VAD), cardiac transplantation, intravenous immunoglobulin (IVIg), mechanical ventilation, and inotrope use. A total of 149 patients with myocarditis (61% male, 48% adolescents) across all PHIS+ centers had TnI (n = 113) or TnT (n = 36) recorded. At least one abnormal Tn was present in 81% of cases. Overall mortality was 7.3% and was not associated with abnormal baseline Tn. Abnormal baseline Tn was associated with ECMO (7.1 vs. 25.6%, p = 0.03) and IVIg (46.4 vs. 83.5%, p < 0.001). Abnormal baseline Tn was not associated with transplantation, mechanical ventilation or inotrope use. Abnormal Tn in the first 72 h of hospitalization for myocarditis was associated with the use of ECMO and IVIg, but was not associated with mortality. This finding may help risk stratify this population if it can be prospectively validated.

<p><strong>Background</strong> In adults with heart failure, elevated heart rate is associated with lower survival. We determined whether an elevated heart rate was associated with an increased risk of death or heart transplant in children with dilated cardiomyopathy. <strong>Methods and Results </strong>The study is an analysis of the Pediatric Cardiomyopathy Registry and includes baseline data, annual follow-up, and censoring events (transplant or death) in 557 children (51% male, median age 1.8&nbsp;years) with dilated cardiomyopathy diagnosed between 1994 and 2011. An elevated heart rate was defined as 2 or more SDs above the mean heart rate of children, adjusted for age. The primary outcomes were heart transplant and death. Heart rate was elevated in 192 children (34%), who were older (median age, 2.3 versus 0.9&nbsp;years; &lt;0.001), more likely to have heart failure symptoms (83% versus 67%; &lt;0.001), had worse ventricular function (median fractional shortening score, -9.7 versus -9.1; =0.02), and were more often receiving anticongestive therapies (96% versus 86%; &lt;0.001) than were children with a normal heart rate. Controlling for age, ventricular function, and cardiac medications, an elevated heart rate was independently associated with death (adjusted hazard ratio [HR] 2.6; &lt;0.001) and with death or transplant (adjusted HR 1.5; =0.01). <strong>Conclusions</strong> In children with dilated cardiomyopathy, elevated heart rate was associated with an increased risk of death and cardiac transplant. Further study is warranted into the association of elevated heart rate and disease severity in children with dilated cardiomyopathy and as a potential target of therapy.</p>

<p><strong>INTRODUCTION: </strong>Unlike the adult heart failure (HF) patient population, there is scarce of information on the overall burden of HF in the pediatric population across geographies and within different age groups. Areas covered: A systematic review aims to describe and quantify the economic, humanistic, and societal burden of pediatric (age &lt;18 years) HF on patients and caregivers. Eighteen published studies over a period of 10-years (Jan 1 2006- May 20 2016) were identified through Embase, Medline, Cochrane Library and selected congresses. Studies from the US reported higher HF-related hospitalization-rates in infants aged &lt;1 year (49.3%-63.9%) versus children aged 1-12 years (18.7%-30.9%) in HF diagnosed patients. Across the studies, average length of hospital-stay was 15 days, increasing to 26 days for infants. Average annual hospital charges were higher for infants (US$176,000) versus children aged 1-10 years (US$132,000) in the US. In Germany, diagnosis-related group (DRG)-based hospital-allowances per HF-case increased from €3,498 in 1995 to €4,250 in 2009. Expert opinion: To our knowledge, this is the first systematic review, which provides valuable insights into burden of HF in children and adolescents, and strengthens current knowledge of pediatric HF. However, there is a need for larger population based studies with wider geographical coverage.</p>

<p><strong>BACKGROUND: </strong>Children with congenital heart disease (CHD) are at risk for advanced heart failure (AHF). We sought to define the mortality and resource utilization in CHD-related AHF in children and young adults.</p>

<p><strong>METHODS: </strong>All hospitalizations in the Pediatric Health Information System database involving patients ≤21 years old with a CHD diagnosis and heart failure requiring at least 7 days of continuous inotropic support between 2004 and 2015 were included. Hospitalizations including CHD surgery were excluded.</p>

<p><strong>RESULTS: </strong>Of 465,482 CHD hospitalizations, AHF was present in 2,712 (0.6%) [58% infant, 55% male, 30% single ventricle]. AHF therapies frequently used included extracorporeal membrane oxygenation (ECMO) (15%) and cardiac transplant (16%). Ventricular assist device (VAD) support was rare (3%), although VAD use significantly increased from 2004 to 2015 (P &lt; .0010). Hospital mortality in CHD with AHF was 26%, with higher mortality associated with single ventricle heart disease (OR 1.64, 95% CI 1.23-2.19; P = .0009), infancy (OR 1.71, 95% CI 1.17-2.5; P = .0057), non-white race (OR 1.28, 95% CI 1.04-1.59; p=0.0234), and chronic complex comorbidities (OR 1.76, 95% CI 1.34-2.30; P &lt; .0001). Over the 11-year study period, despite the significant increase in CHD-related AHF hospitalizations (P &lt; .0001), hospital mortality improved (P = .0011). Median hospital costs were $252,000, a 6-fold increase above those without AHF, and was primarily driven by hospital length of stay (P &lt; .0001).</p>

<p><strong>CONCLUSION: </strong>AHF in children with CHD in uncommon but increasing and is associated with significant morbidity, mortality and resource utilization. Approximately 1 in 5 children do not survive to hospital discharge. Many risk factors for mortality may not be modifiable, and further study is needed to identify modifiable risk factors and improve care for this complex population.</p>

<p><strong>BACKGROUND: </strong>Risk assessment in heart transplantation is critical for candidate selection, but current models inadequately assess individual risk of postoperative mortality. We sought to identify risk factors and develop a scoring system to predict mortality following heart transplantation in children.</p>

<p><strong>METHODS: </strong>The records of patients undergoing heart transplantation at our institution from 2010 - 2016 were reviewed. Clinical characteristics were recorded and compared between survivors and non-survivors. Using Cox proportional hazard modeling, a risk factor score was developed using factors associated with postoperative mortality.</p>

<p><strong>RESULTS: </strong>Seventy-four patients underwent heart transplantation at a mean age of 8.8 ± 6.6 years. Congenital heart disease was the most common indication, comprising 48.6% of the cohort. Overall mortality was 18.9%, with 10/14 dying ≤30 days of operation or during initial postoperative admission (early mortality). The following preoperative factors were associated with overall mortality: single ventricle congenital heart disease (HR 3.2, p = 0.042), biVAD (HR 4.8, p = 0.043), history of ≥4 sternotomies (HR 3.9, p = 0.023), panel reactive antibody &gt; 10% (HR 4.4, p = 0.013), any previous surgery at an outside institution (HR 3.2, p = 0.038), and pulmonary vein disease (HR 4.7, p = 0.045). Each risk factor was assigned a point value, based on similar magnitude of the hazard ratios. A score of ≥4 predicted mortality with 57% sensitivity and 90% specificity.</p>

<p><strong>CONCLUSIONS: </strong>In this single-center pediatric cohort, post-heart transplantation mortality could be predicted using patient-specific risk factors. The cumulative effect of these risk factors predicted mortality with high specificity.</p>

<p>Hypertrophic cardiomyopathy has a range of clinical severity in children. Treatment options are limited, mainly on account of small patient size. Disopyramide is a sodium channel blocker with negative inotropic properties that effectively reduces left ventricular outflow tract gradients in adults with hypertrophic cardiomyopathy, but its efficacy in children is uncertain. A retrospective chart review of patients ⩽21 years of age with hypertrophic cardiomyopathy at our institution and treated with disopyramide was performed. Left ventricular outflow tract Doppler gradients before and after disopyramide initiation were compared as the primary outcome measure. Nine patients received disopyramide, with a median age of 5.6 years (range 6 days-12.9 years). The median left ventricular outflow tract Doppler gradient before initiation of disopyramide was 81 mmHg (range 30-132 mmHg); eight patients had post-initiation echocardiograms, in which the median lowest recorded Doppler gradient was 43 mmHg (range 15-100 mmHg), for a median % reduction of 58.2% (p=0.002). With median follow-up of 2.5 years, eight of nine patients were still alive, although disopyramide had been discontinued in six of the nine patients. Reasons for discontinuation included septal myomectomy (four patients), heart transplantation (one patient), and side effects (one patient). Disopyramide was effective for the relief of left ventricular outflow tract obstruction in children with hypertrophic cardiomyopathy, although longer-term data suggest that its efficacy is not sustained. In general, it was well tolerated. Further study in larger patient populations is warranted.</p>

<p>While the epidemiology of adult heart failure has been extensively researched, this systematic review addresses the less well characterized incidence and prevalence of pediatric HF. The search strategy used Cochrane methodology and identified 83 unique studies for inclusion. Studies were categorized according to whether the HF diagnosis was reported as primary (n = 10); associated with other cardiovascular diseases (CVDs) (n = 49); or associated with non-CVDs (n = 24). A narrative synthesis of the evidence is presented. For primary HF, the incidence ranged from 0.87/100,000 (UK and Ireland) to 7.4/100,000 (Taiwan). A prevalence of 83.3/100,000 was reported in one large population-based study from Spain. HF etiology varied across regions with lower respiratory tract infections and severe anemia predominating in lower income countries, and cardiomyopathies and congenital heart disease major causes in higher income countries. Key findings for the other categories included a prevalence of HF associated with cardiomyopathies ranging from 36.1% (Japan) to 79% (US); associated with congenital heart disease from 8% (Norway) to 82.2% (Nigeria); associated with rheumatic heart diseases from 1.5% (Turkey) to 74% (Zimbabwe); associated with renal disorders from 3.8% (India) to 24.1% (Nigeria); and associated with HIV from 1% (US) to 29.3% (Brazil). To our knowledge, this is the first systematic review of the topic and strengthens current knowledge of pediatric HF epidemiology. Although a large body of research was identified, heterogeneity in study design and diagnostic criteria limited the ability to compare regional data. Standardized definitions of pediatric HF are required to facilitate cross-regional comparisons of epidemiological data.</p>

<p><strong>OBJECTIVES: </strong>To describe the frequency, characteristics, and outcomes of heart failure-related emergency department (ED) visits in pediatric patients. We aimed to test the hypothesis that these visits are associated with higher admission rates, mortality, and resource utilization.</p>

<p><strong>STUDY DESIGN: </strong>A retrospective analysis of the Nationwide Emergency Department Sample for 2010 of patients ≤18 years of age was performed to describe ED visits with and without heart failure. Cases were identified using International Classification of Disease, Ninth Revision, Clinical Modification codes and assessed for factors associated with admission, mortality, and resource utilization.</p>

<p><strong>RESULTS: </strong>Among 28.6 million pediatric visits to the ED, there were 5971 (0.02%) heart failure-related cases. Heart failure-related ED patients were significantly more likely to be admitted (59.8% vs 4.01%; OR 35.3, 95% CI 31.5-39.7). Among heart failure-related visits, admission was more common in patients with congenital heart disease (OR 5.0, 95% CI 3.3-7.4) and in those with comorbidities including respiratory failure (OR 78.3, 95% CI 10.4-591) and renal failure (OR 7.9, 95% CI 1.7-36.3). Heart failure-related cases admitted to the hospital had a higher likelihood of death than nonheart failure-related cases (5.9% vs 0.32%, P &lt; .001). Factors associated with mortality included respiratory failure (OR 4.5, 95% CI 2.2-9.2) and renal failure (OR 7.8, 95% CI 2.9-20.7). Heart failure-related ED visits were more expensive than nonheart failure-related ED visits ($1460 [IQR $861-2038] vs $778 [IQR $442-1375] [P &lt; .01].)</p>

<p><strong>CONCLUSIONS</strong>: Heart failure-related visits represent a minority of pediatric ED visits but are associated with increased hospital admission and resource utilization.</p>

<p>Complement-dependent cytotoxicity crossmatch (CDCXM) is used for evaluation of preformed HLA-specific antibodies in patients undergoing heart transplantation. Flow cytometry crossmatch (FCXM) is a more sensitive assay and used with increasing frequency. To determine the clinical relevance of a positive FCXM in the context of negative CDCXM in heart transplantation, the United Network for Organ Sharing (UNOS) database was analyzed. Kaplan-Meier analysis and Cox proportional hazard modeling were used to assess graft survival for three different patient cohorts defined by crossmatch results: T-cell and B-cell CDCXM+ ("CDCXM +" cohort), CDCXM- but T-cell and/or B-cell FCXM+ ("FCXM+" cohort), and T-cell/B-cell CDCXM- and FCXM- ("XM-" cohort). During the study period, 2,558 patients met inclusion criteria (10.7% CDCXM+, 18.8% FCXM+, 65.5% XM-). CDCXM+ patients had significantly decreased graft survival compared to FCXM+ and XM- cohorts (p=0.003 and &lt;0.001 respectively). CDCXM- and FCXM+ patients did not have decreased graft survival compared to XM- patients (p=0.09). In multivariate analysis, only CDCXM+ was associated with decreased graft survival (HR 1.22, 95% CI 1.01-1.49). In conclusion, positive FCXM in the context of negative CDCXM does not confer increased risk of graft failure. Further study is needed to understand implications of CDCXM and FCXM testing in heart transplant recipients. This article is protected by copyright. All rights reserved.</p>

<p>We used the NEDS database (2010) to evaluate ED utilization in PED HT recipients compared to other patient populations with focus on characteristics of ED visits, risk factors for admission, and charges. We analyzed 433 ED visits by PED HT recipients (median age 8 [range: 0-18] years). The most common primary diagnosis category was infectious (n=163, 37.6%), with pneumonia being the most common infectious etiology. When compared to all PED visits, HT visits were more likely to result in hospital admission (32.6% versus 3.9%, P&lt;.001), had greater hospital LOS (median of 3 days [IQR 2-4] versus 2 days [IQR 1-4], P=.001), and accumulated greater total hospital charges (median $26&nbsp;317 [IQR $11&nbsp;438-$46&nbsp;407] versus $12&nbsp;332 [IQR $7092-$22&nbsp;583], P&lt;.001). When compared to visits by other SOT recipients, results varied with similar rates of hospital admission for HT, LUNGT, and KT visits and similar LOS for HT and KT visits but differing total hospital charges. Although PED HT recipients account for a small percentage of overall ED visits, they are more likely to be hospitalized and require greater resource utilization compared to the general PED population, but not when compared to other SOT recipients.</p>