• During contraction of muscle, thick filaments of myosin slide past thin filaments of actin by calcium-mediated ATP-dependent contraction
    • Released calcium binds to troponin C, T, and I, which regulate muscle contraction
  • Troponins do not change in trauma, skeletal muscle disease, exercise
  • Troponin C found in all tissue and is not cardiac marker
  • Troponin T is qualitative assay
  • Troponin I is quantitative assay
  • High sensitivity troponin T (hsTnT) is a quantitative assay

Cardiac Enzymes Over Time

Type Interval Peak Elevation Return to Normal
Myoglobin 1-4h 6-7h 18-24h
Troponin I 3-12 10-24 3-10d
Troponin T 3-12 10-24 5-14d
CK-MB 4-12 12-24 48-72
LDH 8-12 24-48 10-14d

Differential Diagnosis

Elevated Troponin

True Positive

False (Non-CAD) Positives

  • Pericarditis
  • Myocarditis
  • PE
  • CHF
  • Sepsis
  • Dissection
  • Arrhythmias
  • CVA
  • SAH
  • Burns
  • Renal failure
    • Assume true positive until proven otherwise
  • ESRD
    • 86% elevated predialysis in troponin-T
    • 6% elevated predialysis in troponin-I
      • no difference in post-MI troponin-I clearance rate in ESRD vs. normal GFR
  • Cardioversion
  • Cardiotoxic medications
  • Amyloidosis
  • Rheumatoid Factor
  • Heterophilic antibodies
  • Apical ballooning syndrome
  • Cardiac procedures (surgery, ablation, pacing, stenting)
  • Extreme exertion

See Also

  • Cardiac Enzymes
  • Acute Coronary Syndrome (Main)


    • Jain N, Hedayati SS. How should clinicians interpret cardiac troponin values in patients with ESRD? Seminars in dialysis. 2011;24(4):398-400. doi:10.1111/j.1525-139X.2011.00912.x.
    • Ellis K, Dreisbach AW, Lertora JL. Plasma elimination of cardiac troponin I in end-stage renal disease. South Med J. 2001 Oct;94(10):993-6. PubMed PMID: 11702827.
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