Resumen de Sensitive cardiac troponin in the diagnosis and risk stratification of acute heart failure

N. Arenja, T. Reichlin, B. Drexler, S. Oshima, Kris Denhaerynck, P. Haaf, M. Potocki, T. Breidthardt, M. Noveanu, C. Stelzig, C. Heinisch, R. Twerenbold, M. Reiter, T. Socrates, C. Mueller

• Abstract.  Arenja N, Reichlin T, Drexler B, Oshima S, Denhaerynck K, Haaf P, Potocki M, Breidthardt T, Noveanu M, Stelzig C, Heinisch C, Twerenbold R, Reiter M, Socrates T, Mueller C (University Hospital, Basel). Sensitive cardiac troponin in the diagnosis and risk stratification of acute heart failure. J Intern Med 2012; 271: 598–607.

  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.