Comparison of serum cardiac troponin T and creatine kinase MB isoenzyme mass concentrations in asphyxiated term infants during the first 48 h of life.

Objective: This prospective study aimed to compare serum creatine kinase MB isoenzyme (CK-MB) mass concentrations and cardiac troponin T (cTnT) concentrations during the first 48 h of life in asphyxiated term infants.

Methods: Serum cTnT and CK-MB mass concentrations of 50 term infants with clinical features of perinatal asphyxia were measured at birth and at 12, 24 and 48 h of age by chemiluminescence immunoassay. These infants were followed up until discharge or death. Cord blood CK-MB and cTnT concentrations of 50 healthy term infants were also assayed.

Results: At birth, asphyxiated infants had significantly higher concentrations of cTnT and CK-MB than controls (P < 0.0001). Serum cTnT of asphyxiated infants with low ejection fraction <60% was significantly higher at 12 and 24 h than those with normal ejection fraction (P < 0.05). Asphyxiated infants with congestive cardiac failure had significantly higher serum cTnT concentration during the first 48 h of life than those without congestive cardiac failure (P or= 0.1).

Conclusion: Unlike CK-MB, serum cTnT concentrations are significantly higher in asphyxiated infants who die or develop cardiac dysfunction.