Evaluation of heart fatty acid-binding protein as a rapid indicator for assessment of myocardial damage in pediatric cardiac surgery

OBJECTIVES: Perioperative myocardial damage is a major determinant of postoperative cardiac dysfunction for congenital heart disease. Heart fatty acid-binding protein is reported to be a rapid marker of perioperative myocardial damage that peaks earlier than creatine kinase isoenzyme MB or cardiac troponin T in adults. The objective of this study was to assess the suitability of using serum concentrations of heart fatty acid-binding protein for evaluation of perioperative myocardial damage in pediatric cardiac surgery. METHODS: After institutional review board approval and informed consent, 100 children undergoing open procedures for congenital heart disease were prospectively enrolled in the study. Mean age at operation was 4.9 +/- 0.4 years. Serum concentrations of heart fatty acid-binding protein, creatine kinase isoenzyme MB, and cardiac troponin T were measured serially before operation and at 0, 1, 2, 3, and 6 hours after aortic declamping. Relationships between serum peak level of heart fatty acid-binding protein and intraoperative and postoperative clinical variables were evaluated. RESULTS: Serum heart fatty acid-binding protein reached its peak level at 1 hour after declamping in 95 patients (95%), which was significantly earlier (P <.01) than serum creatine kinase isoenzyme MB or cardiac troponin T. In addition, serum heart fatty acid-binding protein level immediately after declamping correlated strongly with serum peak heart fatty acid-binding protein level (r = 0.91, P <.01). The serum peak level of heart fatty acid-binding protein correlated with those of creatine kinase isoenzyme MB (r = 0.77, P <.01) and cardiac troponin T (r = 0.80, P <.01). In the forward stepwise multiple regression analysis, age (P <.0001), aortic crossclamp time (P <.0001), the presence of a ventriculotomy (P <.001), and the lowest hematocrit level during cardiopulmonary bypass (P <.05) were significant intraoperative variables that influenced the release of heart fatty acid-binding protein. There were significant relationships between serum peak heart fatty acid-binding protein level and postoperative inotropic support, duration of intubation, and intensive care unit stay (P <.01 for each). CONCLUSIONS: Heart fatty acid-binding protein is a rapid marker for assessment of myocardial damage and clinical outcome in pediatric cardiac surgery. In particular, serum heart fatty acid-binding protein level immediately after aortic declamping may be a potentially useful prognostic indicator of myocardial damage as well as clinical outcome in pediatric cardiac surgery.