Predictive value of cardiac troponin T in pediatric patients at risk for myocardial injury.

Abstract

Biochemical markers have not been routinely used in children at risk for myocardial damage. Yet, because of somatic growth and the duration of survival, a low level of myocardial damage may ultimately be of more consequence in children than in adults. We investigated the utility of cardiac troponin T (cTnT) blood levels (CARDIAC T ELISA Troponin T, Boehringer Mannheim Corp) in 51 consecutively sampled patients from 1 day to 34 years of age (median=5.7 years) undergoing cardiovascular (n=19) or noncardiovascular (n=17) surgery or who received doxorubicin for acute lymphoblastic leukemia (ALL) (n=15). Minimum detectable cTnT elevations were 0.03 ng/mL. cTnT was measurable in children of all ages with myocyte damage. In patients who underwent cardiovascular surgery, a correlation was noted between a score of increasing surgical severity and the mean level of postoperative cTnT (r=.79, P<.0001). Postoperative cTnT levels were elevated in children who completed cardiovascular surgery with an open chest compared with those with a closed chest (P=.0083). In addition, cTnT levels before cardiovascular surgery predicted postoperative survival (P=.007). cTnT elevations were observed after initial doxorubicin therapy for ALL. The magnitude of elevation predicted left ventricular dilatation (r=.80 when variables were treated as continuous, P=.003) and wall thinning (r=.61, P=.044) 9 months later. Elevations of blood cTnT in children relate to the severity of myocardial damage and predict subsequent subclinical and clinical cardiac morbidity and mortality.