title: Prognostic value of isolated troponin elevation across the spectrum of chest pain syndromes.
abstract: The risk of death or recurrent myocardial infarction (MI) in patients with chest pain and baseline isolated troponin elevation is unclear. To determine the early and short-term risk of death or MI associated with isolated troponin elevation across a spectrum of chest pain syndromes, we used baseline creatine kinase (CK)-MB and troponin data from the Platelet IIb/IIIa Antagonism for the Reduction of Acute Coronary Syndrome Events in a Global Organization Network (PARAGON) B troponin substudy, the Global Utilization of Strategies To Open Occluded Coronary Arteries (GUSTO) IIa troponin substudy, and the Chest Pain Evaluation by Creatine Kinase-MB, Myoglobin, and Troponin I (CHECKMATE) study. Patients were grouped into 1 of 4 categories based on marker status (troponin-positive/CK-MB-positive, troponin-positive/CK-MB-negative, troponin-negative/CK-MB-positive, or troponin-negative/CK-MB-negative). The adjusted odds of death or MI occurring at 24 hours and 30 days was assessed by baseline marker status using multivariable logistic regression, with the group negative for both markers used as the reference. Patients who were positive for both markers had the highest odds of the 24-hour and 30-day end point. The adjusted odds of the 30-day end point for patients with isolated troponin elevation were 1.3 (95% confidence interval 0.7 to 2.3) and 4.8 (95% confidence interval 1.4 to 16.0) for high- and low-risk patients, respectively. The risk for 24-hour and 30-day death or MI with isolated positive CK-MB results was lower than with isolated positive troponin results, and it was not significantly greater than if the 2 markers were negative. For patients with high- and low-risk chest pain, baseline troponin elevation without CK-MB elevation was associated with increased risk for early and short-term adverse outcomes. This suggests that these patients should be admitted to the hospital and monitored in either an intensive care or step-down unit.
authors.affiliation: Duke Clinical Research Institute, PO Box 17969, Durham, NC 27715, USA. sunil.rao@duke.edu
authors.forename: Sunil V
authors.initials: SV
authors.lastname: Rao
authors.forename: E Magnus
authors.initials: EM
authors.lastname: Ohman
authors.forename: Christopher B
authors.initials: CB
authors.lastname: Granger
authors.forename: Paul W
authors.initials: PW
authors.lastname: Armstrong
authors.forename: W Brian
authors.initials: WB
authors.lastname: Gibler
authors.forename: Robert H
authors.initials: RH
authors.lastname: Christenson
authors.forename: Vic
authors.initials: V
authors.lastname: Hasselblad
authors.forename: Amanda
authors.initials: A
authors.lastname: Stebbins
authors.forename: Steven
authors.initials: S
authors.lastname: McNulty
authors.forename: L Kristin
authors.initials: LK
authors.lastname: Newby
mesh_terms: D000368:Aged; D015415:Biomarkers / Q000097:blood*; D002637:Chest Pain / Q000401:mortality*; D003402:Creatine Kinase / Q000097:blood; D052279:Creatine Kinase, MB Form; D005260:Female; D006801:Humans; D007527:Isoenzymes / Q000097:blood; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000401:mortality; D009211:Myoglobin / Q000097:blood; D016017:Odds Ratio; D011379:Prognosis; D013577:Syndrome; D014336:Troponin / Q000097:blood*; D019210:Troponin I / Q000097:blood
chemical_list: D015415:Biomarkers; D007527:Isoenzymes; D009211:Myoglobin; D014336:Troponin; D019210:Troponin I; D003402:Creatine Kinase; D052279:Creatine Kinase, MB Form