Heart-type Fatty Acid-Binding Protein (H-FABP) in Early Diagnosis of Acute Myocardial Infarction

Abstract

Acute myocardial infarction (AMI), among the most fatal forms of acute coronary syndrome, remains challenging to diagnose accurately in the emergency department, especially during the earliest phase of symptoms, before conventional biomarkers like cardiac troponin and CK-MB become elevated. Here, we reviewed the diagnostic performance of H-FABP in early detection of AMI and considered its potential use in standard diagnostic protocols. H-FABP has low molecular weight (14-15 kDa) and is present free in the cytoplasm of cardiomyocytes. Within one to three hours of myocardial damage, H-FABP is released into the circulation, preceding cardiac troponin, which typically reaches detectable levels after more than four hours. Available evidence suggests that the early sensitivity of H-FABP is superior to troponin alone and using H-FABP and troponin as a dual-biomarker test improves the diagnostic accuracy of early AMI detection and supports early decision-making in patients with acute chest pain in the emergency department. Given that other conditions like renal failure, pulmonary embolism and heart failure can elevate H-FABP levels, this protein cannot be used as a sole marker of AMI diagnosis due to low specificity. Therefore, we concluded that H-FABP could have a role as an adjunctive marker when combined with sensitive cardiac troponin assays, ECG and clinical assessment. Further studies are needed to further evaluate the utility of H-FABP and to standardize cutoff levels and patient populations who would benefit most from H-FABP testing to help its broader use in clinical practice.