Left ventricular endocardial pacing in cardiac resynchronisation therapy: Moving from bench to bedside

Area of Science:

• Cardiology
• Medical Devices
• Electrophysiology

Background:

• Cardiac resynchronisation therapy (CRT) aims to improve heart function by synchronising ventricular contractions.
• Up to 10% of CRT procedures fail to implant a left ventricular (LV) lead in a suitable coronary sinus branch.
• Epicardial lead implantation is the standard alternative but carries significant morbidity and technical challenges.

Purpose of the Study:

• To discuss and compare left ventricular endocardial pacing with traditional epicardial surgical implantation for CRT.
• To evaluate the feasibility, safety, and efficacy of endocardial LV pacing as an alternative CRT strategy.

Main Methods:

• Review of existing literature comparing endocardial LV pacing with epicardial pacing.
• Analysis of acute haemodynamic responses, procedural complications, and morbidity associated with both techniques.
• Discussion of potential long-term risks, particularly thromboembolic events.

Main Results:

• Endocardial LV pacing demonstrates a favourable acute haemodynamic response compared to epicardial pacing.
• Procedural ease, complications, and morbidity associated with endocardial implantation compare favorably to surgical epicardial techniques.
• The long-term risk of thromboembolic complications with endocardial pacing remains unknown due to limited experience.

Conclusions:

• Left ventricular endocardial pacing is a promising alternative for CRT when coronary sinus lead placement fails.
• It offers advantages in procedural simplicity and reduced immediate complications compared to epicardial leads.
• Current recommendations reserve endocardial implants for highly symptomatic heart failure patients or those at high surgical risk, pending further long-term safety data.