title: Cardiac-specific troponin I levels to predict the risk of mortality in patients with acute coronary syndromes.
abstract: BACKGROUND
  In patients with acute coronary syndromes, it is desirable to identify a sensitive serum marker that is closely related to the degree of myocardial damage, provides prognostic information, and can be measured rapidly. We studied the prognostic value of cardiac troponin I levels in patients with unstable angina or non-Q-wave myocardial infarction.
  
  
  METHODS
  In a multicenter study, blood specimens from 1404 symptomatic patients were analyzed for cardiac troponin I, a serum marker not detected in the blood of healthy persons. The relation between mortality at 42 days and the level of cardiac troponin I in the specimen obtained on enrollment was determined both before and after adjustment for baseline characteristics.
  
  
  RESULTS
  The mortality rate at 42 days was significantly higher in the 573 patients with cardiac troponin I levels of at least 0.4 ng per milliliter (21 deaths, or 3.7 percent) than in the 831 patients with cardiac troponin I levels below 0.4 ng per milliliter (8 deaths, or 1.0 percent; P < 0.001). There were statistically significant increases in mortality with increasing levels of cardiac troponin I (P < 0.001). Each increase of 1 ng per milliliter in the cardiac troponin I level was associated with a significant increase (P = 0.03) in the risk ratio for death after adjustment for the base-line characteristics that were independently predictive of mortality (ST-segment depression and age > or = 65 years).
  
  
  CONCLUSIONS
  In patients with acute coronary syndromes, cardiac troponin I levels provide useful prognostic information and permit the early identification of patients with an increased risk of death.
authors.affiliation: Department of Medicine, Brigham and Women's Hospital, Boston, MA 02115, USA.
authors.forename: E M
authors.initials: EM
authors.lastname: Antman
authors.forename: M J
authors.initials: MJ
authors.lastname: Tanasijevic
authors.forename: B
authors.initials: B
authors.lastname: Thompson
authors.forename: M
authors.initials: M
authors.lastname: Schactman
authors.forename: C H
authors.initials: CH
authors.lastname: McCabe
authors.forename: C P
authors.initials: CP
authors.lastname: Cannon
authors.forename: G A
authors.initials: GA
authors.lastname: Fischer
authors.forename: A Y
authors.initials: AY
authors.lastname: Fung
authors.forename: C
authors.initials: C
authors.lastname: Thompson
authors.forename: D
authors.initials: D
authors.lastname: Wybenga
authors.forename: E
authors.initials: E
authors.lastname: Braunwald
mesh_terms: D000208:Acute Disease; D000328:Adult; D000368:Aged; D000789:Angina, Unstable / Q000097:blood / Q000145:classification / Q000401:mortality*; D015415:Biomarkers / Q000097:blood; D003402:Creatine Kinase / Q000097:blood; D005260:Female; D006801:Humans; D007527:Isoenzymes; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009203:Myocardial Infarction / Q000097:blood / Q000145:classification / Q000401:mortality*; D016017:Odds Ratio; D011379:Prognosis; D012189:Retrospective Studies; D012306:Risk; D019210:Troponin I / Q000097:blood*
chemical_list: D015415:Biomarkers; D007527:Isoenzymes; D019210:Troponin I; D003402:Creatine Kinase