The ectopy-triggering ganglionated plexuses in atrial fibrillation

Area of Science:

• Cardiology
• Electrophysiology
• Cardiac Anatomy

Background:

• Epicardial ganglionated plexuses (GP) play a role in atrial fibrillation (AF) pathogenesis.
• The relationship between anatomical, histological, and functional aspects of GP is not fully understood.
• Previous studies identified atrioventricular (AV) dissociating GP (AVD-GP) locations.

Purpose of the Study:

• To map and characterize ectopy triggering GP (ET-GP).
• To understand the neural mechanisms of ET-GP in AF.
• To determine the anatomical distribution of ET-GP in the left atrium (LA).

Main Methods:

• 26 patients with paroxysmal AF underwent left atrial (LA) pacing.
• High-frequency stimulation (HFS) was delivered synchronously with pacing.
• ET-GP locations were mapped onto a 3D LA geometry using CARTO™ 3D system.

Main Results:

• HFS identified 579 (25%) ET-GP out of 2302 tested sites.
• 16% of characterized ET-GP triggered sustained AF or atrial tachycardia (AT).
• ET-GP were predominantly located in the LA roof, mid-anterior wall, and around pulmonary vein ostia.

Conclusions:

• ET-GP can be identified via endocardial stimulation.
• The anatomical distribution of ET-GP differs from AVD-GP.
• Targeting ET-GP may enhance AF ablation outcomes.