Role of heart-type fatty acid binding protein in early detection of acute myocardial infarction in comparison with cTnI, CK-MB and myoglobin

Heart fatty acid-binding protein (H-FABP) is supposed to be the most sensitive biomarker of early acute myocardial infarction (AMI). To evaluate the diagnostic value of H-FABP for AMI in the early stage, the plasma levels of H-FABP were measured by sandwich ELISA in 93 patients with suspected AMI at admission within 6h after onset of chest pain and 69 normal healthy subjects. The plasma concentrations of cardiac troponin-I (cTnI), creatine kinase-MB (CK-MB) and myoglobin (Mb) were assayed at the same time by using corpuscle chemiluminescence for those patients. The patients were classified as AMI group (n=32) and non-AMI group (n=61) retrospecitively. The diagnostic validity was evaluated in terms of sensitivity, specificity and receiver operating characteristics (ROC) curve analysis. The results showed the cutoff value of H-FABP for AMI was 16.8 ng/ml, and it diagnostic sensitivity for AMI was 64.29% within 3h and 84.38% within 6 h after onset of chest pain, and the diagnostic specificity for non-AMI was 100% within 3 h and 91.8% within 6 h. H-FABP had higher sensitivity than that of cTnI and CK-MB at all time points (P<0.05), whereas there was no significant difference in specificity among the four markers. But the area under the ROC curve of H-FABP was significantly greater than that of cTnI, CK-MB and Mb within 3 h. These results revealed that H-FABP possessed high diagnostic sensitivity and specificity for AMI in early stage, especially within 3 h after onset of persistent angina pectoris. In conclusion, H-FABP can be used as a sensitive marker for AMI in the early stage.