title: Sensitive cardiac troponin in the diagnosis and risk stratification of acute heart failure.
abstract: BACKGROUND
  The aim of our study was to investigate the diagnostic and prognostic value of a sensitive cardiac troponin I (s-cTnI) assay in patients with acute heart failure (AHF).
  
  
  METHODS
  Sensitive cardiac troponin I was measured in 667 consecutive patients at presentation to the emergency department with acute dyspnoea. Three s-cTnI strata were predefined: below the limit of detection (<0.01 μg L(-1) , undetectable), detectable but still within the normal range (0.01-0.027 μg L(-1) ) and increased (≥0.028 μg L(-1) , ≥99th percentile). The final diagnosis was adjudicated by two independent cardiologists blinded to the s-cTnI levels. Median follow-up in patients with AHF was 371 days.
  
  
  RESULTS
  Levels of s-cTnI were higher in patients with AHF (n = 377, 57%) compared to patients with noncardiac causes of acute dyspnoea (median 0.02 vs. <0.01 μg L(-1) , P < 0.001). In patients with AHF, in-hospital mortality increased with increasing s-cTnI in the three strata (2%, 5% and 14%, P < 0.001). One-year mortality also increased with increasing s-cTnI (21%, 33% and 47%, P < 0.001). s-cTnI remained an independent predictor of 1-year mortality [adjusted odds ratio 1.03 for each increase of 0.1 μg L(-1) , 95% confidence interval (CI) 1.02-1.05, P < 0.001] after adjustment for other risk factors including B-type natriuretic peptide. The net reclassification improvement was 68% (P < 0.001), and absolute integrated discrimination improvement was 0.18 (P < 0.001). The diagnostic accuracy of s-cTnI for the diagnosis of AHF as quantified by the area under the receiver operating characteristic curve was 0.78 (95% CI, 0.75-0.82).
  
  
  CONCLUSIONS
  Sensitive cardiac troponin I is a strong predictor of short- and long-term prognosis in AHF that helps to reclassify patients in terms of mortality risk. Detectable levels of s-cTnI, even within the normal range, are independently associated with mortality.
authors: Department of Internal Medicine Division of Cardiology, University Hospital, Basel, Switzerland.
authors: N
authors: N
authors: Arenja
authors: T
authors: T
authors: Reichlin
authors: B
authors: B
authors: Drexler
authors: S
authors: S
authors: Oshima
authors: K
authors: K
authors: Denhaerynck
authors: P
authors: P
authors: Haaf
authors: M
authors: M
authors: Potocki
authors: T
authors: T
authors: Breidthardt
authors: M
authors: M
authors: Noveanu
authors: C
authors: C
authors: Stelzig
authors: C
authors: C
authors: Heinisch
authors: R
authors: R
authors: Twerenbold
authors: M
authors: M
authors: Reiter
authors: T
authors: T
authors: Socrates
authors: C
authors: C
authors: Mueller
mesh_terms: D000208:Acute Disease; D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D015415:Biomarkers / Q000097:blood; D016001:Confidence Intervals; D004636:Emergency Service, Hospital; D005260:Female; D005500:Follow-Up Studies; D006333:Heart Failure / Q000097:blood / Q000175:diagnosis* / Q000401:mortality; D006801:Humans; D008297:Male; D016017:Odds Ratio; D011237:Predictive Value of Tests; D011379:Prognosis; D011446:Prospective Studies; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D016019:Survival Analysis; D019210:Troponin I / Q000097:blood*
chemical_list: D015415:Biomarkers; D019210:Troponin I