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>Durable ventricular assist devices (VADs) are increasingly used to treat children with heart failure. Studies demonstrate worse outcomes for those in cardiogenic shock at the time of VAD, but limited data exist on less acutely ill children. We describe the association between illness severity and outcomes in this population.</p>

<p><strong>METHODS: </strong>Data were analyzed from 373 children (aged &lt;19 years) receiving durable VADs from 46 centers in the Pediatric Interagency Registry for Mechanical Circulatory Support. Outcomes were compared by Interagency Registry for Mechanical Circulatory Support (INTERMACS) Patient Profile (PP) and pre-implant characteristics using competing risks methodology.</p>

<p><strong>RESULTS: </strong>Analyses identified 97 patients in cardiogenic shock (PP 1), 222 with progressive decline (PP 2), and 42 stable on inotropes (PP 3). There were 39 infants, 124 were aged 1 to 9 years and 210 were aged 10 to 19 years. A majority had cardiomyopathy and 66 had congenital heart disease (CHD). There were 224 (62%) continuous-flow VADs. Before implant, 40% received mechanical ventilation (MV). Within 6 months post-implant, 57% underwent transplant and 14% died. PP 1 mortality was highest (25% vs 10% for PP 2, hazard ratio [HR]: 2.5, 95% CI: 1.4-4.4, p = 0.02). In PP 1, CHD was an independent mortality risk factor (HR: 2.9, 95% CI: 1.1-7.8, p = 0.03). In PP 2, pulsatile VADs were associated with death (HR: 3.9, 95% CI: 1.6-9.5, p = 0.003). Patients on MV had high mortality (20%-30%) across PP 1 to PP 3 (HR: 3.0 vs no MV, p &lt; 0.001).</p>

<p><strong>CONCLUSIONS: </strong>Children in shock at the time of VAD implant have poor outcomes. MV is associated with increased mortality even in lower acuity INTERMACS profiles. Further study is needed to identify modifiable risk factors in this population.</p>