The prognostic significance of serial myoglobin, troponin I, and creatine kinase-MB measurements in patients evaluated in the emergency department for acute coronary syndrome.
OBJECTIVE
We sought to determine the value of serial measurements of myoglobin, cardiac troponin I (cTnI), and creatine kinase-MB (CK-MB) to predict 30-day adverse events in patients evaluated in the emergency department (ED) for possible acute coronary syndrome.


METHODS
Serum myoglobin, cTnI, and CK-MB levels were measured at presentation, 90 minutes, 3 hours, and 9 hours in patients evaluated in the ED for possible acute coronary syndrome. In 764 consecutive patients, the ability of each individual marker and combination of markers to predict a 30-day adverse event (death or myocardial infarction) over time was calculated.


RESULTS
There were 109 (14%) patients with an adverse event at 30 days (84 myocardial infarctions and 43 deaths). The sensitivities of initial measurements of myoglobin, cTnI, and CK-MB for identifying adverse events were 60%, 47%, and 52%, respectively. The combined sensitivity of myoglobin and cTnI measurements during a 9-hour period was 94%; specificity was 50%. Measurement of CK-MB did not improve sensitivity.


CONCLUSIONS
The measurement of both myoglobin and cTnI during a 9-hour period was the most predictive of subsequent adverse events in patients evaluated in the ED for possible acute coronary syndrome.
McCord
James
J
Henry Ford Heart and Vascular Institute, Detroit, MI 48202, USA. jmccord1@hfhs.org
Nowak
Richard M
RM
Hudson
Michael P
MP
McCullough
Peter A
PA
Tomlanovich
Michael C
MC
Jacobsen
Gordon
G
Tokarski
Glenn
G
Khoury
Nabil
N
Weaver
W Douglas
WD
D000208:Acute Disease; D000368:Aged; D015415:Biomarkers / Q000097:blood; D003327:Coronary Disease / Q000097:blood* / Q000401:mortality; D003402:Creatine Kinase / Q000097:blood*; D004636:Emergency Service, Hospital; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009211:Myoglobin / Q000097:blood*; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D013997:Time Factors; D019210:Troponin I / Q000097:blood*
D015415:Biomarkers; D009211:Myoglobin; D019210:Troponin I; D003402:Creatine Kinase