Fatty acid-binding proteins (FABP) are tissue-specific intracellular molecules of about 15 kD. They are a class of cytoplasmic proteins that bind long-chain fatty acids and play an important role in the intracellular utilization of fatty acids. Different types of FABP have been detected and these include Heart FABP, Liver FABP, and Intestinal FABP, etc.
Human cardiac muscle has a high content of ABP (10-20 mol % of cytoplasmic proteins). Heart FABP (HFABP) is a sensitive biomarker of myocardial necrosis that can be used to confirm or exclude a diagnosis of acute myocardial infarction (AMI) and for monitoring of a recurrent infarction3. In AMI, H-FABP is rapidly released from damaged cardiomyocytes into the circulation due to its small size.
H-FABP levels are significantly elevated above their threshold level within 3 hours after AMI and subsequently return to normal values in 12 to 24 hours7. More recently, H-FABP has been identified as a potential serum biomarker for stroke that is superior to either neuron-specific enolase or S100B8. The normal levels of H-FABP range from 1.6 ng/ml to an upper level of 19 ng/ml in various studies of cardiovascular disease1-7. HFABP increases slightly with age.
Human heart-type fatty acid-binding protein (H-FABP) is a biochemical marker for detecting myocardial injury such as acute myocardial infarction (AMI) Also, blood H-FABP concentrations have been utilized for estimation of the infarct size , ascertaining the success or failure of reperfusion therapy and as an indicator of myocardial injury during open heart surgery. Recently, it has been reported that elevated levels of H-FABP were also found in stroke and certain neurogenerative diseases .
The H-FABP rapid test provides modest additional diagnostic certainty in primary care. It cannot be used to safely exclude rule out ACS. The test can only be used safely in patients otherwise NOT referred to hospital by the GP, as an extra precaution not to miss ACS ('rule in').