Coronary Sinus Electrograms May Predict New-onset Atrial Fibrillation After Typical Atrial Flutter Radiofrequency...

Area of Science:

• Cardiac Electrophysiology
• Interventional Cardiology
• Arrhythmia Management

Background:

• Complex fractionated electrograms (EGMs) from the coronary sinus (CSEs) are targets in radiofrequency ablation (RFA) for atrial fibrillation (AF).
• CSEs anatomically encompass electrical signals from the left atrium (LA), coronary sinus musculature, and right atrium (RA).

Purpose of the Study:

• To evaluate the predictive significance of fractionated CSEs and delayed potentials for new-onset AF.
• To assess these electrical markers following radiofrequency ablation (RFA) for isolated atrial flutter (AFL).

Main Methods:

• Consecutive patients undergoing AFL ablation were analyzed.
• Fractionated and discrete activities in CSEs were recorded during sinus rhythm and pacing.
• Propagation delay of EGMs was measured as the time from earliest CSE to the S wave nadir or R wave peak.

Main Results:

• Fifty percent of patients (20/40) developed AF during a mean 55.1-month follow-up.
• Fractionated proximal and mid CSEs were significantly more prevalent in the AF group (65%, 60%) versus the non-AF group (35%, 30%).
• Delayed proximal CSE propagation during pacing and sinus rhythm was significantly associated with AF incidence (p=0.03 and p=0.02, respectively).

Conclusions:

• Fractionated proximal and mid CSEs during sinus rhythm, and distal CSEs during paced rhythm, are associated with AF incidence after AFL ablation.
• Delayed proximal CSE propagation is a significant predictor of AF development post-ablation.