Understanding LOT-CRT: Current Insights, Limitations, and Our Center's Experience

Area of Science:

• Cardiology
• Electrophysiology
• Medical Devices

Background:

• Biventricular pacing (BiV) is standard for heart failure (HF) with reduced ejection fraction and dyssynchrony, but 33% of patients do not respond.
• Left bundle branch area pacing (LBBAP) offers physiological pacing but is limited by atypical LBBB or IVCD.
• A novel approach, LOT-CRT, combines LBBAP with coronary sinus (CS) lead pacing to enhance electrical synchrony.

Purpose of the Study:

• To review the feasibility, advantages, disadvantages, and clinical outcomes of LOT-CRT.
• To compare LOT-CRT with BiV-CRT and LBBAP alone.
• To propose an evidence-based implantation algorithm for LOT-CRT.

Main Methods:

• Systematic review of published studies on LOT-CRT.
• Comparison of LOT-CRT with BiV-CRT and LBBAP using QRS narrowing, LVEF, remodeling, NYHA class, and NT-proBNP.
• Inclusion of single-center experience and algorithm development.

Main Results:

• LOT-CRT shows improved outcomes compared to BiV-CRT or LBBAP alone in specific patient groups.
• Achieving these benefits requires advanced clinical skills, longer procedures, and specialized device configurations.
• Randomized trials are ongoing to further validate LOT-CRT's efficacy.

Conclusions:

• LOT-CRT represents a significant advancement in cardiac resynchronization therapy for non-responders to conventional CRT.
• Careful patient selection and procedural expertise are crucial for successful LOT-CRT implementation.
• Further research, including randomized controlled trials, is essential to solidify LOT-CRT's role in clinical practice.