Could heart-type fatty acid binding protein predict clinical outcome in coronary artery bypass graft surgery?

Background: Detection of myocardial damage and its degree during open heart surgery were studied previously using different biomarkers. Heart fatty acid binding protein (h-FABP) was used in the diagnosis of myocardial infarction with variable results. In this study, we aimed to find the possibility of the use of this biomarker as a predictor of myocardial damage after coronary artery bypass graft (CABG) surgery. Methods: We conducted a prospective study on 47 patients who had CABG surgery. Blood samples (4 ml) were drawn from patients at 5 points: before induction of anesthesia, after aortic declamping, 1 hour after declamping, 6 hours after declamping and one day after surgery. Levels of h-FABP and creatine kinase muscle/brain (CK-MB) were estimated, and the relationship between h-FABP and operative and postoperative outcomes were recorded. Results: There were statistically significant correlations between higher levels of h-FABP measured immediately after aortic declamping and need for intra-aortic balloon (116.55 + 9.26 vs, 84.34 + 19.55 ng/ml; p= 0.022), inotropes (107.04+ 14.79 vs, 79.95 + 17.59ng/ml; p< 0.001), defibrillators (97.73 + 15.18 vs 81.59 + 20.31 ng/ml; p=0.016), and postoperative atrial fibrillation (99.94 + 17.83 vs 80.84 + 18.89ng/ml; p= 0.004). No mortality was detected in our study. h-FABP levels showed an early peak just after aortic declamping and reached baseline by postoperative day one. CK-MB peaked 1 hour after aortic declamping and remained elevated for more than 24 hours. Conclusion: h-FABP is a cardiac biomarker that could be used as a rapid indicator of ventricular dysfunction and atrial fibrillation post-CABG surgery.