Abstract Body (Do not enter title and authors here): Background:
Atrial fibrillation (AF) is common among cancer patients and poses unique management challenges, especially regarding stroke prevention and bleeding risk. Left atrial appendage occlusion (LAAO) has emerged as a promising non-pharmacological strategy for stroke prevention in patients with non-valvular AF who are at high risk of bleeding. Yet its safety and efficacy in cancer patients remain inadequately characterized. This meta-analysis aimed to evaluate both periprocedural and long-term outcomes of LAAO in patients with AF and cancer.

Methods:
A comprehensive literature search was conducted using PubMed, Embase, and Google Scholar databases. Studies comparing LAAO outcomes in cancer patients with those in non-cancer patients were included in the analysis. Random-effects models were used to calculate Mantel-Haenszel odds ratios (ORs) with 95% confidence intervals (CIs). Statistical significance was set at p < 0.05. Review Manager 5.0 (RevMan) was utilized for all statistical analyses. The outcomes evaluated were periprocedural complications as well as long-term endpoints, including stroke, major bleeding, and all-cause mortality, over a mean follow-up duration of 1.6 years.

Results:
Six studies, including 11,693 cases of cancer with atrial fibrillation (AF), were included. Pooled analysis showed no significant difference in periprocedural complications between cancer and non-cancer patients undergoing the LAAO procedure (OR: 1.20; 95% CI: 0.88–1.63; p = 0.25). Over a mean follow-up of 1.6 years, cancer patients had a significantly lower risk of stroke compared with non-cancer patients (OR: 0.77; 95% CI: 0.61–0.95; p < 0.05). There was no statistically significant difference in the incidence of long-term bleeding events (OR: 1.24; 95% CI: 0.93–1.67; p = 0.15). However, all-cause mortality was significantly higher among cancer patients (OR: 1.75; 95% CI: 1.23–2.48; p < 0.01).

Conclusion:
LAAO appears to be a safe and effective strategy for stroke prevention in cancer patients with AF, with a comparable periprocedural risk profile and lower stroke rates. However, increased all-cause mortality highlights the need for individualized decision-making and further studies to define optimal patient selection.

Keywords: Atrial fibrillation, cancer, left atrial appendage occlusion, stroke, mortality