Our aim was to assess the prognostic impact of a high-sensitivity cardiac troponin T (hs-cTnT) assay in an outpatient population with chronic systolic left ventricular heart failure (HF). Four hundred sixteen patients with chronic HF and left ventricular ejection fraction ≤ 45% were enrolled in a prospective cohort study. In addition to hs-cTnT, plasma amino-terminal pro-B-type natriuretic peptide was measured at baseline. Mean age was 71 years, 29% were women, 62% had coronary artery disease (CAD), mean left ventricular ejection fraction was 31%, and 57% had abnormal level of hs-cTnT. During 4.4 years of follow-up, 211 (51%) patients died. In multivariate Cox regression models, hs-cTnT was categorized as quartiles or dichotomized by the 99th percentile of a healthy population. Adjusted hazard ratios for all-cause mortality for quartiles 2 to 4, with quartile 1 as reference, were 1.4 (95% confidence interval 0.9 to 2.4, p = 0.16) for quartile 2, 1.7 (0.9 to 2.5, p = 0.12) for quartile 3, and 2.6 (1.6 to 4.4, p