Diagnostic value of serial measurement of cardiac markers in patients with chest pain: limited value of adding myoglobin to troponin I for exclusion of myocardial infarction

Am Heart J. 2004 Oct;148(4):574-81. doi: 10.1016/j.ahj.2004.04.030.


Background: Despite improved laboratory assays for cardiac markers and a revised standard for definition of myocardial infarction (AMI), early detection of coronary ischemia in unselected patients with chest pain remains a difficult challenge.

Methods: Rapid measurements of troponin I (TnI), creatine kinase MB (CK-MB), and myoglobin were performed in 197 consecutive patients with chest pain and a nondiagnostic electrocardiogram for AMI. The early diagnostic performances of these markers and different multimarker strategies were evaluated and compared. Diagnosis of AMI was based on European Society of Cardiology/American College of Cardiology criteria.

Results: At a given specificity of 95%, TnI yielded the highest sensitivity of all markers at all time points. A TnI cutoff corresponding to the 10% coefficient of variation (0.1 microg/L) demonstrated a cumulative sensitivity of 93% with a corresponding specificity of 81% at 2 hours. The sensitivity was considerably higher compared to CK-MB and myoglobin, even considering patients with a short delay until admission. Using the 99th percentile of TnI results as a cutoff (0.07 microg/L) produced a cumulative sensitivity of 98% at 2 hours, but its usefulness was limited due to low specificities. Multimarker strategies including TnI and/or myoglobin did not provide a superior overall diagnostic performance compared to TnI using the 0.1 microg/L cutoff.

Conclusion: A TnI cutoff corresponding to the 10% coefficient of variation was most appropriate for early diagnosis of AMI. A lower TnI cutoff may be useful for very early exclusion of AMI. CK-MB and in particular myoglobin did not offer additional diagnostic value.

Publication types

  • Clinical Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Angina, Unstable / blood
  • Angina, Unstable / diagnosis*
  • Biomarkers / blood
  • Chest Pain / blood*
  • Creatine Kinase / blood*
  • Creatine Kinase, MB Form
  • Diagnosis, Differential
  • Female
  • Humans
  • Isoenzymes / blood*
  • Male
  • Middle Aged
  • Myocardial Infarction / blood
  • Myocardial Infarction / diagnosis*
  • Myoglobin / blood*
  • Sensitivity and Specificity
  • Troponin I / blood*


  • Biomarkers
  • Isoenzymes
  • Myoglobin
  • Troponin I
  • Creatine Kinase
  • Creatine Kinase, MB Form