Elevation of cardiac biomarkers comes from injury to:

• A. Myocardium
• B. Pericardium
• C. Blood Vessels
• D. Nerve tissue

Answer: (A)

Cardiac biomarkers rise when cardiac myocytes are damaged. When the myocardium is injured, proteins like troponin I/T are released into the bloodstream, and troponin is highly specific for cardiac muscle, making it the most informative marker for myocardial injury such as in a myocardial infarction. Other markers, like CK-MB, can indicate cardiac injury but are less specific, and myoglobin rises early but is not specific to the heart. Injury to the pericardium, blood vessels, or nerve tissue does not produce the same cardiac-specific biomarker elevation, so the pattern points to myocardium involvement.