Usefulness of cardiac troponin T and echocardiography in the diagnosis of hypoxic myocardial injury of full-term neonates.

Background: Perinatal asphyxia constitutes a significant problem influencing neonatal mortality and morbidity.
Objectives: The aim of the present work was to provide evidence of the usefulness of cardiac troponin T (cTnT) and echocardiographic investigations in the diagnosis of heart damage in full-term infants after intrauterine hypoxia.
Material and Methods: The subjects were 39 asphyxiated and 44 term infants without fetal anoxia. Quantitative determinations of cTnT were performed between 12 and 24 h of life. Two-dimensional Doppler and color Doppler studies were performed at the bedside. We evaluated fractional shortening (FS), cardiac output (CO), cardiac index (CI), tricuspid (TI) and mitral (MI) insufficiency.
Results: Asphyxiated infants presented increased cTnT (mean 0.141+/-0.226 vs. 0.087+/-0.111 ng/ml; p<0.01) and TI (38.5 vs. 11.4% of population; p<0.05) compared to healthy infants. CO, CI and FS remained in the same range.
Conclusions: We found cTnT to be the most useful among accessible diagnostic tools used in post-hypoxic heart damage in neonates. The data from our relatively small population study suggest a cTnT value of >0.1 ng/ml as a reliable marker of myocardial injury in neonates. Further study should be performed to generate a receiver-operator characteristic curve to discover what the cut-off level should be.
(Copyright (c) 2005 S. Karger AG, Basel.)