Admissional B-type natriuretic peptide is an independent predictor of outcome in patients with decompensated heart failure

Background

B-type natriuretic peptide (BNP) is a neurohormone secreted mainly by the cardiac ventricles in response to volume and pressure overload and is increased in patients with congestive heart failure (CHF), especially in those with more severe disease. The aim of this study was to determine the prognostic value of the admissional BNP measurement in patients who present to the emergency department (ED) with decompensated CHF.

Methods

From April 2001 through January 2002, 70 patients were admitted to an ED with decompensated CHF. Mean age was 77 ± 12 years and 37 (53%) were male. BNP was measured in all patients during admission using a rapid bedside test (Triage, Biosite, San Diego, CA, USA). We sought to determine the utility of BNP in predicting the following combined endpoint: hospital mortality + 30-day mortality or readmission. The utility of BNP in predicting outcome was assessed using multivariate logistic regression. The independent variables analysed in the model were age, sex, mean blood pressure, heart rate, ejection fraction, serum sodium, C reactive protein, cardiothorax ratio, and BNP. The receiver operating characteristic curve was used to determine the best cutoff value to predict worse outcome.

Results

During the study 29 endpoints occurred (six hospital deaths, six deaths during the 30-day follow-up and 17 CHF readmissions). BNP concentrations were higher in patients who had an adverse event than in those who did not (952 ± 440 vs 679 ± 456 pg/ml, P = 0.012). The independent predictors of adverse outcomes were BNP (P = 0.012; C statistic = 0.77), mean blood pressure (P = 0.019) and heart rate (P = 0.034). BNP concentrations ≥ 960 pg/ml had sensibility of 70.2% and specificity of 69% in predicting an adverse outcome.

Conclusion

Admissional BNP measurement in patients who present to the ED with decompensated CHF is useful in predicting short-term outcomes.