The diagnostic and prognostic impact of the redefinition of acute myocardial infarction: lessons from the Global Registry of Acute Coronary Events (GRACE).
BACKGROUND
The impact and prognostic value of the redefinition of myocardial infarction (MI) with more sensitive markers have not been evaluated prospectively in a large, less selected population with acute coronary syndrome (ACS).


METHODS
We evaluated the attack and case-fatality rates of MI based on initial and/or peak creatine kinase (CK), creatine kinase-MB (CK-MB), and cardiac troponin (the upper limit of normal [ULN] was defined according to the local hospital's standard) in a prospective observational registry of 26,267 patients with ACS admitted to 106 hospitals in 14 countries.


RESULTS
The addition of cardiac troponin-positive status to CK status as a criterion for the diagnosis of MI resulted in as many as 1 in 4 additional patients meeting the redefined criteria. Compared with patients without elevated levels of CK and cardiac troponin, the crude odds for dying during hospitalization were significantly higher for patients with elevated troponin but not CK levels of greater than or equal to the ULN (odds ratio [OR] 2.2, 95% CI 1.6-2.9), those without CK levels >2 times the ULN (OR 2.8, 95% CI 2.2-3.5), and those with nonelevated levels of CK-MB (OR 2.1, 95% CI 1.4-3.2). The addition of cardiac troponin-positive status significantly increased the multivariable-adjusted odds for hospital death in patients with CK < or =2 times the ULN (OR 1.6, 95% CI 1.2-2.1) but not for patients without elevated levels of CK or CK-MB.


CONCLUSIONS
The prognostic value of cardiac troponin, beyond that supplied by CK status or important baseline characteristics, assists in the identification of patients with ACS who are at increased risk for death.
Goodman
Shaun G
SG
Canadian Heart Research Centre, St Michael's Hospital, University of Toronto, Toronto, Ontario, Canada. goodmans@smh.toronto.on.ca
Steg
Philippe Gabriel
PG
Eagle
Kim A
KA
Fox
Keith A A
KA
López-Sendón
José
J
Montalescot
Gilles
G
Budaj
Andrzej
A
Kennelly
Brian M
BM
Gore
Joel M
JM
Allegrone
Jeanna
J
Granger
Christopher B
CB
Gurfinkel
Enrique P
EP
D000368:Aged; D015415:Biomarkers / Q000097:blood*; D003402:Creatine Kinase / Q000097:blood; D052279:Creatine Kinase, MB Form / Q000097:blood; D005260:Female; D017052:Hospital Mortality; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009203:Myocardial Infarction / Q000175:diagnosis* / Q000401:mortality* / Q000628:therapy; D011379:Prognosis; D012042:Registries; D016019:Survival Analysis; D014336:Troponin / Q000097:blood
D015415:Biomarkers; D014336:Troponin; D003402:Creatine Kinase; D052279:Creatine Kinase, MB Form