Revisiting the clinical evidence of heart rate target in patients with heart failure treated with beta-blockers

Objective: On evaluating the guidelines from previous studies, we found no randomized controlled trials on the use of beta-blockers for heart failure (HF) that employed as evidence for heart rate targets of 60 or 70 beats/min. In this study, we aimed to assess the target heart rate in patients with HF treated with beta-blockers. Methods: We used the keywords, "heart failure" and "beta-blocker" to search PubMed, Ovid, EMBASE, and Cochrane from 1966 to June 2021. Two authors independently reviewed the results of the search strategy and selected all the studies that reported the effect of beta-blockers on all-cause mortality in patients with HFrEF. We conducted analyses using Review Manager, version 5.0 and Stata version 12.0. Risk of bias was assessed regarding randomization, allocation sequence concealment, blinding, incomplete outcome data, and other biases. Sensitivity analysis was carried out to compare the results of fixed effect model with the results of random effect. Results: No clinical trial sup-ported the optimal heart rate of 60 beats/min. Risk ratio (RR) and 95% confidence interval (CI) were 0.77 (0.71, 0.83) and 0.86 (0.76, 0.97) in the subgroup with a baseline heart rate >80 beats/min and subgroup with baseline of <= 80 beats/min, respectively. RR and 95% CI were 0.92 (0.82, 1.02) and 0.77 (0.65, 0.92) in 2 subgroups with heart rate controlled >= 70 beats/min and 60-70 beats/min, respectively. Accumulated to MOCHA 1 trial (heart rate controlled 70 beats/min), there was no significant difference in mortality between the experimental group and the control group (RR=0.91, 95% CI 0.82-1.02). Accumulated to SENIORS trial (heart rate controlled 68.8 beats/min), there was a difference in mortality between the experimental and the control groups (RR=0.90, 95% CI 0.82-0.99). Conclusion: The main effect of beta-blockers in the treatment of HF is achieved by lowering heart rate. The use of beta-blockers did not benefit in people with HFrEF whose heart rate was 77 beats/min before they started the treatment regimen. In patients with HFrEF, the purpose of beta-blockers is to control the heart rate to 65-70 beats min.