Outcomes of Left Bundle Branch Area Pacing for Cardiac Resynchronization Therapy: An Updated Systematic Review and Meta-analysis

ABSTRACT Background Real-world data on the use of left bundle branch area pacing (LBBAP) as an alternative novel pacing strategy to biventricular pacing (BVP) for cardiac resynchronization therapy (CRT) remains scarce. We aimed to investigate the outcomes of LBBAP as an alternative to BVP as a method of CRT. Methods Electronic databases were searched for studies examining the use of LBBAP as CRT and studies comparing LBBAP to BVP. The main outcomes examined were changes in New York Heart Association (NYHA) classification, left ventricular end-diastolic diameter (LVEDD), left ventricular ejection fraction (LVEF), and paced QRS duration post-CRT device implantation. Results Our meta-analysis included eight non-randomized studies with a total of 527 patients who underwent LBBAP as CRT. In studies with a BVP comparison group, patients with LBBAP had a greater reduction in paced QRS [mean difference (MD: 27.91 msec; 95% CI: 22.33-33.50], and a greater improvement in NYHA class (MD: 0.59; 95% CI: 0.28-0.90) and LVEF (MD: 6.77%, 95% CI: 3.84-9.71). Patients with underlying LBBB appeared to benefit the most from LBBAP as compared to patients with underlying non-LBBB. Conclusions LBBAP may be a reasonable option for patients who meet indications for CRT, particularly in those who have limited anatomy or do not benefit from CRT. Randomized trials are needed to compare LBBAP to BVP for CRT and to identify which populations may benefit the most from LBBAP. Brief Summary Real-world data on the use of LBBAP as an alternative CRT to BVP remain scarce. We aim to review existing literature to determine the impact of LBBAP as CRT. Our study is hypothesis-generating, suggesting that LBBAP is a promising novel pacing strategy as resynchronization therapy with comparable clinical outcomes when compared with BVP during short-term follow-up in small, non-randomized studies. Large prospective randomized trials are needed to further evaluate the use of LBBAP on long-term basis.