Cardiac biomarkers myoglobin

In the acute setting of cocaine-induced chest pain, assessment includes the possible diagnosis of acute myocardial infarction. However, cocaine may independently affect cardiac biomarkers [22 ]. Recent cocaine use may alter the specificity of measurement of serum creatine kinase and its MB Iraction. Among cocaine users, increased serum creatine kinase activities and increased mean myoglobin concentrations are common. Increased skeletal muscle activity and rhab-domyolysis are often present, possibly because of cocaine-induced hyperthermia. Troponin I concentrations are more reliable cardiac biomarkers for detecting cocaine-induced myocardial infarction and are associated with a poor prognosis. 

Diagnosis of cardiac muscle injury relies on the detection of biomarkers such as troponin I (Tnl), troponin C (TnC), myoglobin, fatty acid binding protein (FABP), glycogen phosporylase isoenzyeme BB (GPBB), C-reactive protein (CP), urinary albumin, creatine kinase myocardial band (CK-MB), and brain (B-type) natriuretic peptide in blood and urine [28-30]. 

Another major cardiac injury biomarker is myoglobin, the cytoplasmic protein storing and shuttling oxygen from the cell surface to the mitochondria. This small protein can be easily measured by species-specific immunoassays (Spangenfhal and Ellis... 

Although CK and LD isozymes and myoglobin are sensitive biomarkers of skeletal muscle injury, they are also found in cardiac muscle and thus are not tissue specific. Cardiotoxicity must be excluded in order to use them effectively as biomarkers. Injured muscle releases other enzymes in significant amounts, such as alanine aminotransferase (ALT), aspartate aminotransferase (AST), and aldolase however, these also lack tissue specificity. 

Serum biomarkers of acute coronary syndrome play a critical role in the diagnosis and risk stratification of patients with ACS. Myocardial necrosis observed in patients with ACS releases a variety of proteins into blood that can be used as biomarkers. Antiquated markers include aspartate aminotransferase, lactate dehydrogenase (LD) and its isoenzyme (LDl), myoglobin, and creatine kinase (CK) and its isoenzyme (CK-MB). While some of these markers are still in routine use, there is consensus among experts in the field of cardiology, emergency medicine, and laboratory medicine that cardiac troponin is the gold standard marker for ACS. 

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