Abstract Body (Do not enter title and authors here): Introduction: Atrial fibrillation is the most encountered arrhythmia in clinical settings, with an estimate of 6 million cases in the United States. A growing amount of evidence has been supporting the role of left atrial appendage in left sided atrial fibrillation with conflict results. We aim in this study to provide a more in-depth guide for optimal left sided atrial fibrillation ablation strategy.

Methods: We searched PubMed, Web of Science, Cochrane and Scopus for published studies until May 2024. We included relevant studies that compared the left atrial appendage electrical isolation versus the standard ablation and reported our outcomes of interest. The main outcomes of the study were the recurrence of atrial arrhythmia and the incidence of stroke or transient ischemic attack during the follow-up period. Data were pooled as Mean difference (MD) or risk ratio (RR) with their 95% CI using a fixed-effect model.

Results: Eleven studies with 3040 patients were included in the final analysis. Left atrial appendage electrical isolation was associated with a significant reduction in atrial arrhythmia recurrence compared to the standard ablation alone (OR: 0.41, 95% CI: 0.35 to 0.48). However, it was also associated with a significant increase in stroke or transient ischemic attack incidence (OR: 1.48, 95% CI: 1.09 to 3.12).

Conclusion: Left atrial appendage electrical isolation led to a significantly lower atrial arrhythmia recurrence, but this was achieved with an increased risk of stroke and transient ischemic attack incidence during the follow-up period.