Heart type fatty acid binding protein (HFABP) is a novel cytoplasmic protein rich in the heart. It has high cardiac specificity (i.e. mainly expressed in cardiac tissue), but also has low concentrations of expression in tissues outside the heart. After the onset of myocardial ischemic injury, HFABP can be detected in the blood as early as 1-3 hours after the onset of chest pain, reaching its peak at 6-8 hours, and plasma levels return to normal within 24-30 hours. Therefore, HFABP is considered a useful biomarker for early diagnosis of myocardial injury. Heart type fatty acid binding protein (HFABP, also known as FABP3) is composed of 132 amino acids with a molecular weight of 15 kDa. It is one of the most abundant proteins in the heart. HFABP binds two fatty acid molecules and participates in the transport of fatty acyl CoA, active in the oxidation process, thereby generating energy in mitochondria. Heart type fatty acid binding protein (HFABP) is a novel cytoplasmic protein rich in the heart. It has high cardiac specificity (i.e. mainly expressed in cardiac tissue), but also has low concentrations of expression in tissues outside the heart. After the onset of myocardial ischemic injury, HFABP can be detected in the blood as early as 1-3 hours after the onset of chest pain, reaching its peak at 6-8 hours, and plasma levels return to normal within 24-30 hours. Therefore, HFABP is considered a useful biomarker for early diagnosis of myocardial injury. Elevated levels of free plasma myoglobin are widely accepted markers of early myocardial injury and have been shown to be superior in excluding acute myocardial infarction (AMI) within 3-6 hours after symptom onset compared to elevated levels of CK-MB and cTnT. However, HFABP is more cardiac specific and is considered a more accurate diagnostic test due to its biological characteristics.