Long-Term Stroke Risk in Patients Undergoing Left Atrial Appendage Ablation With and Without Complete Isolation

Area of Science:

• Cardiology
• Electrophysiology
• Stroke Prevention

Background:

• Catheter ablation (CA) for atrial fibrillation (AF) may extend beyond pulmonary veins.
• Previous studies suggest additional left atrial (LA) ablation, especially of the left atrial appendage (LAA), may increase stroke risk.
• This study investigates the long-term risk of ischemic stroke or transient ischemic attack (IS/TIA) following LAA ablation versus other ablation strategies.

Purpose of the Study:

• To assess the long-term risk of IS/TIA in patients undergoing CA for AF.
• To compare IS/TIA risk between patients with LAA ablation and those with pulmonary vein isolation (PVI) alone or PVI with non-LAA ablation.
• To identify specific LA ablation locations associated with increased IS/TIA risk.

Main Methods:

• Retrospective analysis of 350 patients undergoing CA for AF between 2008 and 2018.
• Ablation locations in the LA included posterior wall, anterior wall, inferior wall, inter-atrial septum, lateral wall, and LAA.
• Patients with LAA ablation were categorized into complete isolation (LAAi) and without complete isolation (LAAa).

Main Results:

• Mean follow-up was 4.8 years; overall IS/TIA risk was 1.62/100 patient-years.
• LAAi group had the highest IS/TIA risk (3.81/100 pys), followed by LAAa (3.74/100 pys).
• LAAi (HR 3.32, p=0.03) and LAAa (HR 3.18, p=0.02) were significant predictors of IS/TIA after adjusting for oral anticoagulant use and CHA₂DS₂-VASc score.

Conclusions:

• Ablation at the LAA, with or without complete isolation, is independently associated with increased long-term IS/TIA risk in AF patients undergoing CA.
• These findings highlight the need for careful consideration of stroke risk in patients undergoing LAA ablation.
• Strategies like LAA closure should be considered to mitigate stroke risk in these high-risk patients.