Atrial-based pacing for sinus node dysfunction in dogs: initial results

Area of Science:

• Veterinary Cardiology
• Cardiac Electrophysiology

Background:

• Sick sinus syndrome (SSS) necessitates consideration of atrioventricular (AV) node function due to preserved atrial impulse conduction.
• Atrial pacing (AAI) is a potential treatment modality for sinus node dysfunction (SND).

Purpose of the Study:

• To evaluate the feasibility and long-term outcomes of atrial pacing (AAI) in dogs diagnosed with sinus node dysfunction (SND).

Main Methods:

• Retrospective review of medical records for sixteen dogs with SND that underwent AAI pacing.
• Analysis of follow-up data ranging from 45 to 1,227 days.

Main Results:

• One dog developed atrioventricular (AV) block postoperatively.
• Lead dislodgement (3/16) and pericardial perforation (2/16) were observed.
• Rising pacing thresholds, potentially due to lead microdislodgement or fibrosis, occurred in 3/16 dogs.

Conclusions:

• Clinically significant AV block is unlikely long-term in dogs with SND undergoing AAI pacing.
• Lead-related complications may be influenced by operator skill and lead characteristics.
• Optimizing lead selection and pacing location could mitigate complications in canine SND.