Cardiac troponin T levels and myocardial involvement in children with severe respiratory syncytial virus lung disease

Abstract

To determine the prevalence of myocardial damage in severe respiratory syncytial virus (RSV) disease as evident from elevated cardiac Troponin T (cTnT) levels. To assess the nature of the myocardial involvement as manifested in electro- and echocardiographic abnormalities. To compare severity of disease with and without myocardial involvement as evident from duration of ventilation, inotrope requirements and death. This was a prospective observational cohort study of children with RSV infection admitted to the paediatric intensive care unit at the Royal Liverpool Children's Hospital during the winter season 2002/2003. cTnT concentrations were measured using a third generation monoclonal sandwich immunoassay (Roche Diagnostics). 34 children were included in our study. 12 (35%) had elevated cTnT levels. The levels measured after admission had a median [interquartile range (IQR)] of 50 pg/ml (37.5-67.5). There was no significant difference (p > 0.05) between patients with and without elevated cTnT levels with regards to gender, gestational age at birth, history of neonatal intensive care, presence of congenital heart disease, chronic lung disease, inotrope requirements, duration of ventilation, death, fractional shortening on echocardiogram or arrhythmias. Children with elevated cTnT levels were significantly younger [median (IQR): 1.4 months (0.8-2.0)] than children without [median (IQR): 4.0 months (1.7-6.6)] (p = 0.04). The systolic blood pressure on admission was lower in children with increased cTnT compared to those with undetectable cTnT (p = 0.01). Myocardial involvement is common in infants with severe RSV lung disease without congenital heart disease. cTnT level elevation was associated with hypotension.