B-type natriuretic peptide and peak exercise oxygen consumption provide independent information for risk stratification in patients with stable congestive heart failure Original Research Article

Objectives The aim of this study was to compare the prognostic value of peak oxygen consumption (Vo2) and B-type natriuretic peptide (BNP) in patients with stable congestive heart failure (CHF). Background Previous studies have demonstrated that both peak Vo2 and BNP are useful for risk stratification in patients with CHF. No study has compared the respective prognostic value of these two parameters in a large series of patients receiving a combination of angiotensin-converting enzyme inhibitors and of beta-blockers. Methods Patients with stable CHF underwent radionuclide angiography, echocardiography, 24-h Holter monitoring, and a cardiopulmonary exercise test. Blood samples were drawn for standard measurements and for hormonal determinations. Results After a median follow-up period of 787 days, there were 75 cardiac-related deaths and three urgent transplantations. Independent predictors of cardiac survival were percent of maximal predicted Vo2 (%Vo2, relative risk [RR] = 2.84 [95% confidence interval, CI = 1.73 to 4.65], p < 0.00001), BNP (RR = 3.17 [95% CI 1.68 to 5.96], p = 0.0004), left atrial diameter (LAD) (RR = 2.04 [95% CI 1.25 to 3.34], p = 0.004), age (RR = 1.93 [95% CI 1.22 to 3.05], p = 0.005), and aldosterone (RR = 1.84 [95% CI 1.12 to 3.00], p = 0.015). In patients with infra-median levels of BNP (<109 pg/ml), age was the only independent predictor of cardiac survival. However, in patients with supra-median levels of BNP, independent predictors of cardiac survival were %Vo2 (RR = 3.76 [95% CI 2.19 to 6.45], p < 0.00001) and LAD (RR = 1.90 [95% CI 1.10 to 3.28], p = 0.02). Conclusions B-type natriuretic peptide, in combination with %Vo2, improves risk stratification of patients with stable CHF.