Is hormonal activation during exercise useful for risk stratification in patients with moderate congestive heart failure?

Abstract

Background We previously demonstrated that A-type natriuretic peptide (ANP) at peak exercise was an independent predictor of cardiac survival. No data are available concerning the predictive value of B-type natriuretic peptide (BNP) at peak exercise. Methods One hundred and fifty consecutive stable patients with moderate congestive heart failure (CHF) underwent echocardiography and a cardiopulmonary exercise test. Blood samples were drawn at rest and at peak exercise for the determination of plasma levels of ANP, BNP, and norepinephrine. Results Exercise significantly increased plasma values of ANP, BNP, and norepinephrine. After a median follow-up period of 1171 days, there were 35 cardiac related deaths. Mortality rates at 1 and 2 years were 4% and 8%, respectively. Independent predictors of cardiac survival were percent of maximal predicted oxygen consumption (RR = 4.8 [2.1–11], P = .002), BNP at rest (RR = 2.5 [1.2–5.6], P = .01), and left atrial diameter (RR = 2.8 [1.2–6.5], P = .02). Conclusions In patients with stable, moderate CHF, plasma levels of ANP, BNP, and norepinephrine measured at peak exercise did not improve risk stratification. However, in addition to percent of maximal predicted oxygen consumption and left atrial diameter, plasma level of BNP at rest was an independent predictor of survival in CHF patients with low risk of cardiac events.