Physiological cardiac pacing: Current status.

Area of Science:

• Cardiology
• Electrophysiology
• Medical Devices

Background:

• Right ventricular (RV) pacing is associated with adverse hemodynamic effects, often attributed to atrioventricular (AV) dyssynchrony.
• Dual-chamber pacemakers, while maintaining AV synchrony, have not consistently outperformed single-chamber RV apical pacing in major clinical outcomes.
• This has prompted research into alternative pacing sites for improved physiological activation and hemodynamics.

Purpose of the Study:

• To explore alternative ventricular pacing sites beyond the RV apex.
• To evaluate the hemodynamic and electrical activation benefits of His bundle, Para-Hisian, and ventricular septal pacing.
• To assess the efficacy of selective atrial pacing in preventing atrial fibrillation (AF) in specific patient groups.

Main Methods:

• Review of existing literature on ventricular pacing strategies and their hemodynamic consequences.
• Analysis of studies comparing RV apical pacing with alternative sites like His bundle, Para-Hisian, and ventricular septal pacing.
• Examination of data on atrial septal pacing for AF prevention in patients with atrial conduction disorders.

Main Results:

• Direct His bundle and Para-Hisian pacing represent the most physiological ventricular pacing options but pose technical challenges.
• Ventricular septal pacing demonstrates potential for reduced electrical activation delay and mechanical dyssynchrony compared to apical pacing, though results are heterogeneous.
• Selective atrial pacing shows promise for AF prevention in patients with atrial conduction abnormalities.

Conclusions:

• Current RV pacing strategies have limitations, necessitating exploration of alternative pacing sites.
• His bundle and Para-Hisian pacing offer physiological advantages but require advanced techniques.
• Ventricular septal pacing and selective atrial pacing are promising alternatives for improving pacing outcomes and preventing AF.