Left Bundle Branch (LBB) Area Pacing for Cardiac Resynchronization Therapy (CRT): Most Promising Alternative CRT Pacing Modality: LBB Area Pacing for CRT

Cardiac resynchronization therapy (CRT) via biventricular pacing (BiVP) has benefitted a large group of heart failure (HF) patients with low (<35%) left ventricular (LV) ejection fraction (LVEF) and cardiac dyssynchrony, mostly in the form of left bundle branch (LBB) block, conferring amelioration of their HF symptoms and prolongation of their survival. However, it entails a tedious procedure to place and find a stable and functional position of the LV lead in a coronary sinus tributary, which may fail in a considerable percentage of patients, while up to one third of patients, even then, may turn out to be non-responders. Over the recent years, strong new data from observational studies and meta-analyses have shown the safety and feasibility of LBB area pacing (LBBAP) in patients with bradyarrhythmias and most importantly in HF patients in need for CRT. LBBAP yields satisfactory pacing threshold and R wave sensing and low complication rates. Particularly, in patients with CRT indication, LBBAP, as an alternative approach to CRT, has shown significant improvement of functional class and LVEF during short-and mid-term follow-up. Thus, LBBAP, as a relatively novel CRT modality, demonstrates a most promising potential (equivalent or even superior) role for effective CRT for HF patients in need of a viable alternative to BiVP, and also circumvents certain limitations of His bundle pacing, which is another, albeit potentially problematic, mode of CRT. Nevertheless, we are still in dire need for confirmatory data from properly designed randomized controlled trials to further establish the role and value of this alternative CRT pacing modality. Rhythmos 2022;17(4): 71-74