II. Epidemiology

  1. Sensitivity: 100% of Myocardial Infarctions
  2. Specificity: Low (36% have Unstable Angina)
    1. See Troponin for false possible causes

III. Labs: Timing Following Acute Myocardial Infarction

  1. Serum levels increase within 4-8 hours of MI onset
  2. Serum levels peak at 12 to 48 hours
  3. Serum levels are elevated for 4-10 days after MI

IV. Advantages

  1. More specific than Troponin T
  2. Not falsely elevated in Chronic Renal Failure

V. Technique: ED Acute Coronary Syndrome evaluation

  1. Obtain 2 Troponin values 6 hours apart

VI. Interpretation

  1. Level >1.0 to 1.2 suggestive of Myocardial Infarction
  2. Two negative values 3-6 hours apart
    1. Predicts low likelihood of Acute Coronary Syndrome

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Related Studies

Ontology: Troponin I (C0077401)

Definition (NCI) Troponin I, troponin T, and troponin C are the three closely associated subunits of the troponin complex of thin filaments in muscle. The complex serves as a calcium-sensitive switch that regulates muscle contraction. In the absence of calcium, Troponin I binds actin, inhibits actomyosin ATPase activity, and inhibits F-actin-myosin interactions. The troponin I gene family comprises three isoforms: skeletal TNI-fast, skeletal TNI-slow, and TNI-cardiac. (from OMIM 191044, 191043, 191042 and NCI)
Definition (MSH) One of the three polypeptide chains that make up the TROPONIN complex. It inhibits F-actin-myosin interactions.
Concepts Biologically Active Substance (T123) , Amino Acid, Peptide, or Protein (T116)
MSH D019210
SnomedCT 102683006
English Troponin I, Troponin-I, inhibitory troponin I, TnI, Troponin I [Chemical/Ingredient], tni, troponin-i, troponin i, Inhibitory troponin subunit, Troponin I (substance)
Swedish Troponin I
Czech troponin I
Finnish Troponiini I
Japanese トロポニンI
Polish Troponina I
Croatian Troponin I
Spanish subunidad de troponina inhibitoria, troponina I (sustancia), troponina I, Troponina I
French Troponine I
German Troponin I
Italian Troponina I
Portuguese Troponina I

Ontology: Troponin I measurement (C0920210)

Definition (NCI) The determination of the amount of troponin I present in a blood sample.
Definition (NCI_CDISC) A measurement of the actin binding troponin in a biological specimen.
Concepts Laboratory Procedure (T059)
SnomedCT 121870001
English Troponin I, Troponin I Measurement, troponin i level test, troponin i test, Troponin I measurement, TROPONI, Troponin I measurement (procedure)
Italian Troponina I
Japanese トロポニンI, トロポニンI
Czech Troponin I
Hungarian Troponin I
Spanish medición de troponina I (procedimiento), medición de troponina I, Troponina I
Portuguese Tropoinina I
Dutch troponine-I
French Troponine I
German Troponin I