5. Conclusion
In all studies included in this meta-analysis, LBBAP in patients with HFmrEF was feasible and safe. In the pooled analysis, LBBAP was found to significantly shorten the QRS duration and improve cardiac systolic function in patients with an LVEF of 35–50%. This suggests that the application of LBBAP as a resynchronization strategy for patients with HFmrEF could be an acceptable option, especially in patients with both HFmrEF and dyssynchrony where a decrease in LVEF is anticipated. A randomized, prospective study is warranted to evaluate the effect of LBBAP-CRT on patients with HF and an LVEF >35% and ≤35%.