What is the primary biomarker used to identify myocardial infarction?

The primary biomarker used to identify myocardial infarction is troponin. Troponin is a protein complex found in cardiac muscle, and its presence in the bloodstream is a highly specific indicator of heart muscle injury. When a myocardial infarction occurs, troponin is released into the circulation as cardiac muscle cells are damaged.

Troponin levels rise within a few hours after the onset of myocardial injury and can remain elevated for several days, allowing for effective diagnosis even after the event. This sensitivity and specificity make troponin the preferred biomarker for diagnosing myocardial infarctions in clinical practice.

While myoglobin, CK-MB, and lactate dehydrogenase are also markers that can indicate cardiac issues or muscle damage, they lack the specificity and reliability of troponin for diagnosing myocardial infarctions. Myoglobin can elevate quickly after injury but is not specific to cardiac tissue; CK-MB is more specific than myoglobin but not as sensitive or long-lasting as troponin. Lactate dehydrogenase can indicate tissue damage but is not a front-line marker for myocardial infarction. Thus, troponin is recognized as the gold standard biomarker for assessing myocardial infarction.