Serial changes in high-sensitive troponin I predict outcome in patients with decompensated heart failure

Aims The aim of this study was to evaluate the prognostic utility of small troponin I (TnI) elevations, serial TnI measurements, and the combination of TnI and brain natriuretic peptide (BNP) in patients with decompensated heart failure (HF). Methods and results One hundred and forty-four patients with acute HF were followed from admission to 90 days post-discharge. Primary endpoints were all cause mortality and HF-related readmission. Troponin I and BNP levels were checked on admission, discharge, and up to four consecutive days during hospitalization. A discharge TnI cut-off of 23.25 ng/L and discharge BNP cut-off of 360 ng/L were determined by receiver operator characteristic (ROC). Troponin I above 23.25 ng/L is associated with increased risk for mortality and readmission (P = 0.003). Comparing with TnI quartile 1, TnI quartiles 2-4 had increased mortality and readmission, P = 0.019, P = 0.007, P = 0.014, respectively. Compared with patients with low TnI+low BNP, increased mortality and readmission were seen in patients with high TnI+high BNP (P 0.007), high TnI+low BNP (P = 0.015), and low TnI+high BNP (P = 0.042). Patients with increasing TnI during treatment had increased mortality compared with patients with stable or decreasing TnI (P = 0.047). In multivariate analysis, TnI reached statistical significance (P = 0.009), while BNP did not. Conclusion This study demonstrates that very small TnI elevations and BNP elevations are associated with increased 90-day mortality and readmission. When compared by ROC and multivariate analysis, TnI is as good a predictor of mortality and readmission as BNP if not slightly better. Patients with increasing TnI during hospitalization for acute HF had increased risk for 90-day mortality.