Effect of Beta-blocker Treatment on V˙O2peak in Patients with Heart Failure
In addition to prolonged life and reduced hospitalization rates, it is currently unclear whether beta-blocker (BB) treatment modulates peak oxygen consumption (V˙O2peak), a hallmark of exercise capacity, in patients with heart failure (HF). The main aim of this study is to determine the effect of BB treatment on V˙O2peak in HF patients.Methods
We conducted a systematic search of MEDLINE, Scopus, and Web of Science since their inceptions until March 2017 for randomized controlled trials (RCT) assessing the effect of BB treatment on V˙O2peak in chronic HF patients. A meta-analysis was performed to ascertain the standardized mean difference (SMD) between the effects of BB and placebo treatment on V˙O2peak. Secondary outcomes included peak exercise performance and New York Health Association functional class. Subgroup and meta-regression analyses assessed potential moderating factors.Results
Fourteen RCT met the inclusion criteria (overall n = 616). Interventions comprised BB (n = 324) or placebo (n = 292) administration lasting 3 to 24 months. Concomitant reported medication did not differ between HF patients assigned to BB and placebo groups. After data pooling, V˙O2peak was preserved with BB compared with placebo treatment (SMD, −0.04; 95% confidence interval (CI), −0.20 to 0.12; P = 0.61); heterogeneity among studies was not detected (I2 = 0%, P = 0.88). Peak exercise performance was not altered (SMD, 0.02; 95% CI, −0.16 to 0.20; P = 0.85), whereas New York Health Association functional class was reduced with BB compared with placebo (SMD, −0.54; 95% CI, −0.90 to −0.18; P = 0.003).Conclusions
According to evidence from RCT, prolonged BB (B1-selective or nonselective) treatment does not affect V˙O2peak but improves functional status in HF patients.