Peak oxygen consumption as a predictor of death in patients with heart failure receiving β-blockers

Peak oxygen uptake (peak VO2) is a strong predictor of mortality and is commonly used in the evaluation of patients for cardiac transplantation. Beta-blockers reduce mortality in patients with heart failure, without influencing peak VO2, raising the possibility that peak VO2 is no longer suitable as an indicator of prognosis in these patients. We analyzed prospectively gathered data on 2105 patients referred for cardiopulmonary testing for all-cause mortality and for occurrence of death or transplantation. Patients receiving beta-blockers were younger, more likely to have coronary disease, and had a greater mean ejection fraction but had a similar peak VO2. There were 555 deaths (26%) and 194 (9%) transplants during a median follow-up of 3.5 years. Peak VO2 was a predictor of mortality irrespective of beta-blocker use; a decrease of 1 mL x kg(-1) x min(-1) resulted in an adjusted hazard ratio (HR) of 1.13 (95% CI 1.09 to 1.17, P