Importance of early combined N-terminal pro-brain natriuretic peptide and cardiac troponin T measurements for long-term risk stratification of patients with decompensated heart failure.

BACKGROUND

Markers of myocardial necrosis and natriuretic peptides are risk predictors in decompensated heart failure (DHF). We prospectively studied the optimal timing of combined cardiac troponin T (cTnT) and N-terminal pro-brain natriuretic peptide (NT-proBNP) measurements for long-term risk stratification.

METHODS

cTnT and NT-proBNP were measured upon admission, and before discharge in 76 patients hospitalized for DHF (mean age 62.3 +/- 15 years; 71% men).

RESULTS

During a mean follow-up of 252 +/- 120 days, 39.5% of patients died or were re-hospitalized for DHF. From receiver-operator-characteristic (ROC) curves, the selected cut-off values for cTnT and NT-proBNP were 0.026 ng/ml and 3,700 pg/ml on admission, and 0.030 ng/ml and 3,200 pg/ml, respectively, at discharge. Depending upon measurements above vs below cut-off, the population was distributed on admission and before discharge for three groups: both negative (24% and 30% of patients); one positive (43% and 42%); and both positive (33% and 28%). For the admission groups, the 1-year DHF-free re-hospitalization survival rates were 85%, 60% and 34%, respectively (p = 0.0047). One-year survival rates for DHF-free re-hospitalization were 63%, 71% and 26% (p = 0.0029), respectively, for the discharge groups. In the Cox proportional hazards model, systolic blood pressure (hazard ratio [HR]: 0.98; 95% confidence interval [CI]: 0.96 to 0.99), heart rate (HR: 0.97; 95% CI: 0.94 to 0.98), one positive biomarker on admission (HR: 10.5; 95% CI: 1.3 to 83.7) and two positive biomarkers on admission (HR: 13.9; 95% CI: 1.8 to 98.5) were independent predictors of long-term outcomes. However, NT-proBNP on admission was the most important predictor of long-term prognosis (HR: 5.1; 95% CI: 2.3 to 12.2).

CONCLUSIONS

The combined measurements of cTnT and NT-proBNP on hospital admission were more reliable than their measurements before discharge in the long-term risk stratification of DHF. A single positive measurement on admission predicted a poor long-term outcome.