Which cardiac biomarker is most commonly associated with myocardial infarction?

Troponin I and Troponin T are the most commonly associated cardiac biomarkers for diagnosing myocardial infarction. These proteins are released into the bloodstream when the heart muscle is damaged, such as during an MI. The specificity and sensitivity of troponins make them the preferred biomarkers in clinical practice for detecting myocardial injury. Troponin I and T levels begin to rise within a few hours of myocardial damage and can remain elevated for several days, allowing for effective detection of an infarction.

In contrast, while creatine kinase (particularly the CK-MB isoform) has been used historically in the diagnosis of myocardial infarction, it is less specific than troponins and can be elevated in other conditions affecting muscle. B-type natriuretic peptide is primarily used to assess heart failure rather than myocardial infarction. Lactate dehydrogenase does have a role in myocardial infarction diagnosis, but its levels can be affected by a variety of other conditions, making it less reliable than troponins. Thus, the use of troponin I and T is the gold standard in contemporary medical practice for diagnosing myocardial infarction.