05/01/2026
๐๐๐ซ๐๐ข๐๐ ๐๐ข๐จ๐ฆ๐๐ซ๐ค๐๐ซ๐ฌ:
Primary cardiac biomarkers used to diagnose and monitor myocardial infarction (heart attack). In clinical practice, we use these markers because they are released into the bloodstream at different times following heart muscle damage.
๐ด๐. ๐๐ซ๐จ๐ฉ๐จ๐ง๐ข๐ง (๐๐ก๐ ๐๐จ๐ฅ๐ ๐๐ญ๐๐ง๐๐๐ซ๐)
Troponin is the most sensitive and specific marker for cardiac injury. Because it is almost exclusively found in the heart, any elevation (when combined with clinical symptoms) is highly suggestive of a heart attack.
๐๐ฅ๐ข๐ง๐ข๐๐๐ฅ ๐๐ญ๐ข๐ฅ๐ข๐ญ๐ฒ: Primary diagnostic tool for Myocardial Infarction (MI).
๐๐ข๐ง๐๐ญ๐ข๐๐ฌ: It rises within 3โ6 hours of injury and can remain elevated for up to 10โ14 days.
๐๐ง๐ญ๐๐ซ๐๐๐ซ๐๐ง๐๐๐ฌ: Elevations can sometimes be seen in chronic kidney disease or severe sepsis, so it must be interpreted alongside an ECG.
:
๐ด๐. ๐๐-๐๐ (๐๐ซ๐๐๐ญ๐ข๐ง๐ ๐๐ข๐ง๐๐ฌ๐-๐๐)
CK-MB is an isoenzyme found mostly in the heart, but also in small amounts in skeletal muscle.
๐๐ฅ๐ข๐ง๐ข๐๐๐ฅ ๐๐ญ๐ข๐ฅ๐ข๐ญ๐ฒ: Most useful for detecting reinfarction. Because it returns to baseline quickly (within 48โ72 hours), a second rise in CK-MB levels can indicate a new, subsequent heart attack that Troponin might mask.
๐๐ง๐ญ๐๐ซ๐๐๐ซ๐๐ง๐๐๐ฌ: Severe skeletal muscle trauma or intense exercise can cause "false" elevations.
๐ด๐ฏ. ๐ ๐๐ผ๐ด๐น๐ผ๐ฏ๐ถ๐ป:
Myoglobin is an oxygen-binding protein found in all muscle tissue. It is the first marker to rise after injury.
๐๐น๐ถ๐ป๐ถ๐ฐ๐ฎ๐น ๐จ๐๐ถ๐น๐ถ๐๐: High negative predictive value. Because it rises so early (within 1โ2 hours), if a patient has chest pain and the myoglobin is normal, we can often "rule out" an immediate MI.
๐๐ถ๐บ๐ถ๐๐ฎ๐๐ถ๐ผ๐ป: Very low specificity. It rises due to any muscle damage (like a heavy workout or a fall), so a high value does not automatically mean a heart attack.
