Elevated Troponin in the First 72 h of Hospitalization for Pediatric Viral Myocarditis is Associated with ECMO: An Analysis of the PHIS plus Database

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.