Abstract Body (Do not enter title and authors here): Background: Persistent atrial fibrillation (AF) involves extensive atrial remodeling beyond pulmonary vein (PV) triggers, making catheter ablation less effective than in paroxysmal AF. PV isolation (PVI) is standard, but outcomes remain limited by broader arrhythmogenic substrates. Linear ablation aims to interrupt reentrant circuits and may improve outcomes when combined with PVI. However, its benefits remain debated due to procedural risks and incomplete lesions.
Methods: We conducted a systematic review and meta-analysis (PRISMA guidelines), searching PubMed, Embase, Scopus, and Web of Science up to February 24, 2025. Eligible studies included randomized controlled trials (RCTs) and observational studies comparing PVI plus linear ablation versus PVI alone in adults with persistent AF. The primary outcome was AF recurrence; secondary outcomes were atrial arrhythmia recurrence and complications. Hazard ratios (HRs) and risk ratios (RRs) with 95% confidence intervals (CIs) were calculated using a random-effects model. Heterogeneity was assessed using the I² statistic. Significant heterogeneity was considered present if I² ≥ 50% and/or p < 0.10. Sensitivity was assessed using leave-one-out analysis, and heterogeneity was explored using subgroup analyses. Publication bias was also assessed using funnel plots.
Results: Out of 113 articles, 4 were included (3 RCTs and 1 cohort study), with 1,431 patients: 696 (48.6%) underwent PVI plus linear ablation, and 735 (51.4%) underwent PVI alone. PVI plus linear ablation reduced AF recurrence (HR: 0.71; 95% CI: 0.54-0.91; p=0.009) and atrial arrhythmias (HR: 0.79; 95% CI: 0.64-0.98; p=0.03) compared to PVI alone. No significant difference in complications was found (RR: 0.43; 95% CI: 0.06-2.92; p=0.39). No significant heterogeneity or possible publication bias (symmetry in the funnel plots) was observed.
Conclusion: This is the first meta-analysis exploring the addition of linear ablation to PVI in persistent AF. The findings suggest that this strategy reduces the risk of atrial arrhythmia recurrence without increasing complications, supporting its potential role in persistent AF ablation strategies. However, the limited number of studies and procedural variability highlight the need for further large-scale RCTs to confirm these results and guide patient selection. Clinicians should carefully consider individual patient characteristics and procedural factors when deciding on the best ablation approach.