Abstract 4367370: Comparative Outcomes of Catheter Ablation for Atrial Arrhythmias in ATTR Cardiac Amyloidosis: A Systematic Review and Meta-Analysis

Introduction: Catheter ablation is an important rhythm control strategy for atrial arrhythmias. Arrhythmia recurrence rates are higher in amyloid than in non-amyloid populations. In this meta-analysis, we aim to quantify the risk of heart failure hospitalizations and mortality in patients with cardiac amyloidosis undergoing catheter ablation compared to those without ablation. Methods: A systematic search of PubMed, Embase, CENTRAL, and Web of Science was conducted to identify studies comparing catheter ablation versus no ablation in patients with cardiac amyloidosis and atrial arrhythmias. Eligible studies reported clinical outcomes stratified by treatment group. Statistical analysis was conducted using Review Manager (RevMan) version 9.3.0 with a random-effects model. Outcomes included HF hospitalization and all-cause mortality. Heart failure hospitalization was assessed through two separate analyses based on data availability: a pooled rate ratio meta-analysis using event rates adjusted for person-years of follow-up, and a separate meta-analysis using hazard ratios. Effect sizes were reported as rate ratios and HRs with 95% confidence intervals. Results: Three retrospective cohort studies comprising 231 patients with cardiac amyloidosis and atrial arrhythmias were included. Median follow-up ranged from 37.2 to 60 months. Patients were predominantly male (70.8%–83%), with mean ages ranging from 74 to 81 years. Catheter ablation significantly reduced the risk of heart failure hospitalization compared to no ablation (rate ratio 0.22, 95% CI 0.11–0.46), and (HR 0.24, 95% CI 0.09–0.61). All-cause mortality was also significantly lower in the ablation group (HR 0.42, 95% CI 0.24–0.73). No significant heterogeneity was observed across studies in any of the analyses. Conclusion: Catheter ablation was associated with a significant reduction in HF hospitalizations and all-cause mortality. Prior meta-analyses of randomized controlled trials in non-amyloid populations have shown similar effects. However the magnitude of benefit observed in ATTR-CM appears more pronounced. This likely reflects the amplified hemodynamic consequences of atrial fibrillation in amyloid hearts, where rapid ventricular rates and loss of atrial contraction can precipitate decompensation. While randomized trials are lacking, the consistency across observational data underscores the potential of catheter ablation to reduce morbidity and mortality in this high-risk population.