title: ST2 and mortality in non-ST-segment elevation acute coronary syndrome.
abstract: BACKGROUND
  ST2 is a member of the interleukin-1 receptor family that is up-regulated in conditions associated with increased myocardial strain. ST2 has been shown to be independently predictive of adverse outcome in heart failure and ST-segment elevation myocardial infarction, but its prognostic value in non-ST-elevation acute coronary syndrome (NSTE-ACS) has not been established.
  
  
  METHODS
  We measured ST2 at randomization and after 24, 48, and 72 hours in 403 NSTE-ACS patients from the GUSTO IV study, and studied its kinetics and its associations to clinical baseline factors and 1-year mortality.
  
  
  RESULTS
  Median ST2 levels decreased from 28.4 U/mL at randomization to 21.8 U/mL at 72 hours (P < .001). Peak levels were noted 6 to 17 hours after symptom onset. Randomization ST2 levels were independently associated to N-terminal pro-B-type natriuretic peptide but otherwise exhibited only weak relations to cardiovascular risk factors and comorbidities, and biomarkers of myocardial necrosis or inflammation. ST2 was related to 1-year mortality independently of clinical risk indicators (odds ratio 2.3 [95% CI 1.1-4.6], P = .03) but lost its predictive value after additional adjustment for prognostic biomarkers, in particular N-terminal pro-B-type natriuretic peptide.
  
  
  CONCLUSIONS
  ST2 levels are elevated early in NSTE-ACS and predict 1-year mortality. Our data indicate that ST2 represents an interesting novel pathophysiologic pathway in the setting of ischemia-related myocardial dysfunction. However, future prospective evaluations in larger populations are needed before the clinical utility of ST2 can be determined.
authors.affiliation: Department of Medical Sciences, Uppsala University, Sweden. kai.eggers@ucr.uu.se
authors.forename: Kai M
authors.initials: KM
authors.lastname: Eggers
authors.forename: Paul W
authors.initials: PW
authors.lastname: Armstrong
authors.forename: Robert M
authors.initials: RM
authors.lastname: Califf
authors.forename: Maarten L
authors.initials: ML
authors.lastname: Simoons
authors.forename: Per
authors.initials: P
authors.lastname: Venge
authors.forename: Lars
authors.initials: L
authors.lastname: Wallentin
authors.forename: Stefan K
authors.initials: SK
authors.lastname: James
mesh_terms: D054058:Acute Coronary Syndrome / Q000097:blood* / Q000401:mortality / Q000503:physiopathology; D000368:Aged; D005260:Female; D006801:Humans; D000072179:Interleukin-1 Receptor-Like 1 Protein; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D011956:Receptors, Cell Surface / Q000097:blood*
chemical_list: C079241:IL1RL1 protein, human; D000072179:Interleukin-1 Receptor-Like 1 Protein; D011956:Receptors, Cell Surface