Introduction
Cardiac resynchronization therapy (CRT) is the first-line treatment for patients with systolic dysfunction heart failure (HF) and ventricular asynchrony [1]. Biventricular pacing (BVP) substantially improves functional capacity and quality of life and reduces morbidity and mortality among patients with heart failure with reduced ejection fraction (HFrEF) with left bundle branch block (LBBB) > 150 msec. However, BVP is hindered by cardiac venous anatomy and difficulty in LV lead positioning, and thus, up to 30% of patients are CRT non-responders [1-3] . Several studies have shown that left bundle branch area pacing (LBBAP), which is reverse LV remodeling in patients with HFrEF indicated for CRT, is practical in patients with HF and bradycardia [4,5] . LBBAP can lead to a relatively narrow QRS duration (QRSd) and rapid left ventricular activation with direct excitation distal to the LBBB site, thus improving clinical and echocardiographic findings [6].
Thus, the benefits of LBBAP, such as improvement in clinical and echocardiographic findings and fewer complications, have gained interest as a potential alternative to BVP [7-21] . However, the data to support these notions remain controversial. Accordingly, this systematic review and meta-analysis aimed to determine the benefits in patients with HFrEF who underwent LBBAP implantation.