II. Epidemiology
- Sensitivity: 100% of Myocardial Infarctions
-
Specificity: Low (36% have Unstable Angina)
- See Troponin for false possible causes
III. Labs: Timing Following Acute Myocardial Infarction
- Serum levels increase within 4-8 hours of MI onset
- Serum levels peak at 12 to 48 hours
- Serum levels are elevated for 4-10 days after MI
IV. Advantages
- More specific than Troponin T
- Not falsely elevated in Chronic Renal Failure
V. Technique: ED Acute Coronary Syndrome evaluation
- Obtain 2 Troponin values 6 hours apart
VI. Interpretation
- Level >1.0 to 1.2 suggestive of Myocardial Infarction
- Two negative values 3-6 hours apart
- Predicts low likelihood of Acute Coronary Syndrome