Arrhythmic Risk in Biventricular Pacing Compared With Left Bundle Branch Area Pacing: Results From the I-CLAS Study.

Area of Science:

• Cardiology
• Electrophysiology
• Medical Devices

Background:

• Cardiac resynchronization therapy (CRT) aims to improve heart function in patients with heart failure.
• Left ventricular ejection fraction (LVEF) ≤35% is a common indication for CRT.
• Left bundle branch area pacing (LBBAP) is an alternative pacing strategy to biventricular pacing (BVP).

Purpose of the Study:

• To compare the incidence of sustained ventricular tachycardia/ventricular fibrillation (VT/VF) and new-onset atrial fibrillation (AF) between LBBAP and BVP.
• To evaluate the safety and efficacy of LBBAP versus BVP in patients undergoing CRT.

Main Methods:

• The I-CLAS study included 1778 patients undergoing CRT (BVP or LBBAP) between 2018 and 2022.
• Propensity score-matched analysis (1:1 ratio) was performed on 1414 patients.
• Incidence of VT/VF and new-onset AF was assessed using Cox proportional hazards survival models.

Main Results:

• LBBAP showed significantly lower rates of VT/VF (4.2% vs 9.3%) and VT storm (0.8% vs 2.5%) compared to BVP.
• New-onset AF was also significantly lower with LBBAP (2.8% vs 6.6%) compared to BVP.
• These findings remained significant after adjusting for baseline characteristics.

Conclusions:

• LBBAP is associated with a lower incidence of VT/VF and new-onset AF compared to BVP.
• Physiological resynchronization achieved by LBBAP may contribute to a reduced risk of arrhythmias.
• LBBAP represents a promising alternative pacing strategy for CRT.