Comparison between creatine kinase MB, heart-type fatty acid-binding protein, and cardiac troponin T for detecting myocardial ischemic injury after cardiac surgery

Background: Heart-type fatty acid-binding protein (H-FABP) is a cytoplasmic protein and is released form necrotic cardiac myocytes, as well as ischemic cardiac myocytes. In this study, we compared creatine kinase MB (CK-MB), H-FABP, and cardiac troponin T (cTnT) after coronary artery bypass grafting (CABG), heart valve surgery, or septal defect surgery to evaluate the difference in detecting myocardial injury between three markers. Methods: A total of 69 patients (CABG, 32; valve surgery, 27; and septal defect surgery, 10) were prospectively enrolled. Blood samples were taken at specific intervals. Results: Mean amount (AUC _0-72h ) of CK-MB and cTnT released for 72 h in the patients with valve surgery were 2446 h·ng/ml and 93.2 h·ng/ml, which were significantly larger than those in the patients with CABG or septal defect surgery (p <.05). Mean amount (AUC _0-72h ) of H-FABP released for 72 h in the patients with CABG was 1939 h·ng/ml, which was significantly larger than that in the patients with septal defect surgery (700.1 h·ng/ml) (p <.05). Conclusion: H-FABP would be a more useful marker for detecting myocardial ischemic injury than CK-MB and cTnT. CK-MB and cTnT would be more sensitive to myocardial injury with surgical trauma than with ischemic injury in the patients with cardiac surgery.