title: Persistent cardiac troponin I elevation in stabilized patients after an episode of acute coronary syndrome predicts long-term mortality.
abstract: BACKGROUND
  In patients with non-ST-elevation acute coronary syndrome, any troponin elevation is associated with an increased risk for cardiovascular events. However, the prevalence and prognostic importance of persistent troponin elevation in stabilized patients after an episode of non-ST-elevation acute coronary syndrome are unknown and were therefore assessed in this study.
  
  
  RESULTS
  Cardiac troponin I (cTnI) was measured in 1092 stabilized patients at 6 weeks and 3 and 6 months after enrollment in the FRagmin and Fast Revascularization during InStability in Coronary artery disease (FRISC-II) trial. cTnI was analyzed with the Access AccuTnI assay with the application of different prognostic cutoffs. Outcomes were assessed through 5 years. Elevated cTnI levels >0.01 microg/L were found in 48% of the study patients at 6 weeks, in 36% at 6 months, and in 26% at all 3 measurements. cTnI elevation was associated with increased age and other cardiovascular high-risk features. The lowest tested cTnI cutoff (0.01 microg/L) was prognostically most useful and was independently predictive of mortality (hazard ratio, 2.1 [95% confidence interval, 1.3 to 3.3]; P=0.001) on multivariable analysis adjusted for cardiovascular risk factors and randomization to an invasive versus noninvasive treatment strategy, whereas it was related to myocardial infarction only on univariate analysis.
  
  
  CONCLUSIONS
  Persistent minor cTnI elevation can be detected frequently in patients stabilized after an episode of non-ST-elevation acute coronary syndrome with the use of a sensitive assay. Elevated cTnI levels >0.01 microg/L predict mortality during long-term follow-up. Our results emphasize the importance of further troponin testing in non-ST-elevation acute coronary syndrome patients after hospital discharge.
authors.affiliation: Department of Medical Sciences, Cardiology, University Hospital Uppsala, S-751 85 Uppsala, Sweden. kai.eggers@akademiska.se
authors.forename: Kai M
authors.initials: KM
authors.lastname: Eggers
authors.forename: Bo
authors.initials: B
authors.lastname: Lagerqvist
authors.forename: Per
authors.initials: P
authors.lastname: Venge
authors.forename: Lars
authors.initials: L
authors.lastname: Wallentin
authors.forename: Bertil
authors.initials: B
authors.lastname: Lindahl
mesh_terms: D000208:Acute Disease; D000368:Aged; D000369:Aged, 80 and over; D017322:Clinical Trials, Phase II as Topic; D003324:Coronary Artery Disease / Q000097:blood* / Q000401:mortality / Q000628:therapy; D018572:Disease-Free Survival; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000097:blood* / Q000401:mortality / Q000628:therapy; D010351:Patient Discharge; D016032:Randomized Controlled Trials as Topic; D015996:Survival Rate; D013577:Syndrome; D013997:Time Factors; D019210:Troponin I / Q000097:blood*
chemical_list: D019210:Troponin I