(183) Outcomes of antiarrythmic drugs versus catheter ablation for treatment of atrial fibrillation in an elderly population

Background: Catheter ablation (CA) is an effective therapy for the treatment of atrial fibrillation, but is often withheld from elderly patients due to uncertainty in efficacy and increased procedural risk given the lack of evidence to guide decision making. Consequently, elderly patients are often continued on anti-arrhythmic drugs (AADs), despite frequent side effects burden and suboptimal outcomes.

Objectives: Compare clinical outcomes and healthcare utilization among elderly patients with AF who underwent treatment with CA versus AADs.

Methods: A large nationally-representative sample of patients over 65 years from January 2016 to December 2022 with commercial insurance and Medicare Advantage was studied using Optum Clinformatics Data Mart. Patients with a prior diagnosis of AF and history of AAD prescription were identified and categorized as AAD or CA cohorts based on treatment after initial prescription fill. The primary outcome was recurrence of AF, atrial flutter, or atrial tachyarrhythmia in 12 months after the index treatment. Secondary outcomes were electrical cardioversions, death, heart failure hospitalizations, myocardial infarctions, and ischemic strokes. Inverse probability of treatment weighting was used to balance covariates between cohorts and clinical outcomes were compared using a weighted Cox proportional hazard model.

Results: 13,311 eligible patients aged over 65 years were identified, with 7,230 in the AAD cohort and 6,081 in the CA cohort. Covariates were well balanced post-weighting, including adherence to oral anticoagulants. Patients who underwent CA were significantly less likely to experience recurrence of atrial tachyarrhythmia (Hazard Ratio [HR]: 0.76, 95% Confidence interval [CI]: 0.65 – 0.89). There was a significant reduction in electrical cardioversions (HR: 0.74, 95% CI: 0.60-0.91), heart failure hospitalizations (HR: 0.63, 95% CI: 0.45 –0.90), and ischemic strokes (HR: 0.45, 95% CI: 0.28 – 0.72) among patients undergoing CA versus AAD treatment. There was no difference in death or myocardial infarctions. Results were similar between patients in 65-74 and over 75 years subgroups (recurrence of atrial tachyarrhythmia 65-74 years HR: 0.78 [95% CI: 0.65-0.94]; over 75 years HR: 0.76 [95% CI: 0.58-0.996]).

Conclusions: Among elderly patients with AF, CA was associated with 24% lower risk of atrial tachyarrhythmia, 26% lower risk of cardioversion, 37% lower risk of heart failure hospitalization, and 55% lower risk of ischemic stroke compared to ongoing treatment with AADs. Patients older than 75 years had a similar risk profile and benefits to younger cohort (65-74 years) and should be considered candidates for CA.