H-FABP (Heart fatty acid binding protein, FABP3) is a sensitive biomarker for myocardial infarction (MI). H-FABP is released from cardiac myocytes following an ischemic episode and can be detected in the blood within one to three hours of chest pain onset. To identify myocardial infarction and acute coronary syndrome, a combination of H-FABP with troponin shows increased sensitivity over troponin alone in patients with chest pain onset. H-FABP also has prognostic value, as it is proved to be a statistically significant predictor of death or MI, independent of troponin T, ECG and clinical examination. The FABP3 assay has been validated for human serum, plasma, urine, cerebrospinal fluid, bronchoalveolar lavage fluid, amniotic fluid and tissue homogenates and has a very high sensitivity (LOD 5.6 pg/ml). H-FABP is a small cytosolic protein expressed predominantly in the cardiac myocytes; it is found at much lower levels in skeletal muscle, kidney, liver and small intestine. H-FABP can quickly pass through the kidney and be measured noninvasively in urine.