Purpose: To examine the prognostic importance of both plasma atrial natriuretic and B-(brain natriuretic peptide) following an episode of acute heart failure.
Subjects and methods: A prospective cohort of 91 patients admitted into hospital with acute heart failure were recruited. After initial in-hospital management plasma ANP and BNP levels were measured by radioimmunoassay, and echocardiography was performed on the same day. Patients were followed up for 12 months and the main outcome measure was cardiovascular death.
Results: Plasma ANP and BNP levels were significantly higher in patients who died of a cardiovascular cause within 12 months (P<0.001 and P<0.0001, respectively) or at 1-month (P<0.05 and P<0.001) after recruitment. By Kaplan-Meier estimated life-table curves, patients with above median plasma ANP or BNP levels had significantly higher 1-year mortality (42.5% vs. 11.6%, both P<0.005). By multivariate Cox proportional hazard regression analysis, the plasma BNP level was the most important prognostic factor predicting mortality (chi2 = 18.3, P<0.0001), followed by age (chi2 = 11.5, P<0.001). Other factors including ANP, left ventricular ejection fraction by M-mode echocardiography, pulmonary arterial pressure, sex, cause of heart failure as well as New York Heart Association class were not significant.
Conclusion: A plasma BNP level has independent and at least short-term prognostic significance in patients admitted with acute heart failure. This non-invasive and readily available blood test should be considered for risk stratification in patients with acute heart failure.