Abstract 4141439: Catheter ablation and clinical outcomes among older Medicare beneficiaries with atrial fibrillation

Background: Catheter ablation (CA) is increasingly used for treatment of atrial fibrillation (AF). However, CA has not been widely adopted in the older population with AF. The aim of this study is to examine the risks of adverse outcomes following CA in older people with AF. Methods: Using 2014-2019 Medicare claims, we conducted a propensity score analysis of patients treated with CA within 6 months of new AF diagnosis to patients treated with only antiarrhythmic therapy in the 6-month period. The outcome follow-up began after the 6-month period. Cox proportional hazards models were used to estimate hazard ratios (HR) for the composite and individual endpoints from CABANA trial (death, stroke, major bleeding or cardiac arrest) and CASTLE-AF trial (death or heart failure). Subgroup analyses were performed by sex, race-ethnicity, social deprivation index, frailty and dementia. Results: The study population comprised of 14623 AF patients (mean age, 76.1±7.6 years; 55% female, 28% frailty, 13% dementia), including 8% receiving CA. The mean follow-up was 1.8 years. Compared to patients with only antiarrhythmic therapy, patients treated with CA had lower rates of CABANA endpoints (CA vs antiarrhythmic therapy: 5.6 vs 11.7 per 100 person-years; HR:0.72, 95%CI:0.66-0.77) and CASTLE-AF endpoints (6.5 vs 13.8 per 100 person-years; HR:0.72, 95%CI:0.67-0.78). The benefits of CA were consistent in both female and male for CABANA endpoints (female: HR:0.71, 95%CI:0.64-0.79 and male: HR:0.72, 95%CI:0.65-0.81) and CASTLE-AF endpoints (female: HR:0.65, 95%CI:0.59-0.73 and male: HR:0.78, 95%CI:0.71-0.87), and in both frail and non-frail patients for CABANA endpoints (frail: HR:0.72, 95%CI:0.66-0.80 and non-frail: HR:0.70, 95%CI:0.63-0.77) and CASTLE-AF endpoints (frail: HR:0.89, 95%CI:0.81-0.97 and non-frail: HR:0.69, 95%CI:0.63-0.75). Similar trends were observed for subgroups defined by race-ethnicity, social deprivation index, and dementia. Conclusions: These findings suggest that CA may be beneficial for older AF patients. Nonetheless, further investigation of the safety and efficacy of CA given to older patients in well-designed interventional trials are warranted.