Atrial Pacing Negatively Affects Left Atrial Morphological and Functional Parameters Similarly to Atrioventricular...

Area of Science:

• Cardiology
• Biomedical Engineering
• Medical Devices

Background:

• Atrioventricular (AV) dyssynchrony and pacemaker pacing influence left atrial (LA) function.
• Dual-chamber pacemaker implantation can lead to morphological and functional changes in the LA.

Purpose of the Study:

• To evaluate the impact of atrial and ventricular pacing on LA morphological and functional changes post-dual-chamber pacemaker implantation.
• To investigate the relationship between pacing burden and LA function in patients with sinus node disease (SND) or atrioventricular block (AVB).

Main Methods:

• 121 subjects with dual-chamber pacemakers were prospectively enrolled.
• Subjects were grouped based on indication (SND/AVB) and pacing settings (e.g., DDDR 60, DDD 60, DDD 40).
• LA function was assessed using echocardiography, measuring volumetric parameters and strain, at one and three months post-implantation.

Main Results:

• A high atrial (A) pacing burden with low ventricular (V) pacing (high A, low V) significantly decreased LA reservoir and contractile strain after three months.
• In the low A, high V group, re-established AV synchrony maintained LA reservoir strain.
• The high A, high V group showed a trend towards decreased LA reservoir strain, though not statistically significant.

Conclusions:

• High atrial pacing burden, independent of AV dyssynchrony and ventricular pacing, impairs LA function and morphology.
• These negative effects on LA parameters occur shortly after pacemaker implantation and are sustained.
• Pacemaker programming strategies should consider the potential impact of high atrial pacing on left atrial function.