Abstract 3015: Drug and Device Effects on Peak Oxygen Consumption as a Predictor of Therapeutic Effects on Mortality in Heart Failure Randomized Trials
Introduction: Peak oxygen consumption (peak VO2) during stress testing is a predictor of mortality in patients with heart failure (HF) and reduced ejection fraction (EF). It is not known whether drug or device-induced changes in this measure predict the effect of such therapies on mortality.
Methods: PubMed was systematically reviewed for randomized, placebo-controlled trials (RCTs) of drug or device therapies for patients with HF and reduced EF. The dataset was limited to therapies that had mortality data in RCTs of >500 patients with >6 months of follow up. RCTs of the effect of those therapies on peak VO2 were then identified, and limited to RCTs of >4 weeks duration. The odds ratio for death in the mortality RCTs was correlated with the placebo-corrected change in peak VO2 for each intervention. Results: We identified mortality RCTs of 24 distinct therapies with a median follow-up of 13 months that directed the search for RCTs of the effect of those therapies on peak VO2. There were 35 peak VO2 trials (n=3,360 patients) involving 18 distinct drug/device therapies with a median follow-up of 24 weeks included. The odds ratio for mortality of the therapies was not correlated with the drug/device-induced placebo-corrected change in peak VO2 (Spearman’s rho=−0.06, p=0.75, Figure⇓). Of the 22 peak VO2 trials that correspond to therapies with favorable effects on mortality, only 27% show a significant increase in peak VO2. Conclusion: Drug- or device-induced effect on peak VO2 does not predict therapeutic effects on mortality for patients with HF and reduced EF. While peak VO2 may objectively reflect functional capacity, it is not a surrogate for an intervention’s effect on long-term mortality.