Abstract 8: Outcomes following Catheter Ablation of Atrial Fibrillation in Medicare Beneficiaries

Background: Atrial fibrillation (AF) is the most common heart dysrhythmia and risk increases with advancing age. Guidelines advocate catheter ablation as a treatment for AF in patients who have failed antiarrhythmic drug therapy. However, little is known about outcomes associated with AF ablation in elderly patients. Methods: We obtained administrative claims for all Medicare fee-for-service beneficiaries ≥65 years who underwent intracardiac catheter ablation from 7/1/2007 to 12/31/2009. Outcomes included mortality, stroke/TIA, pericardial effusion, new MI, and vascular complications requiring surgery within 30 days, and mortality, stroke/TIA, heart failure, new hospitalization, and repeat AF ablation within 1 year. We used Kaplan-Meier methods to calculate unadjusted outcome rates overall and by age, and multivariable Cox models to examine predictors of 1-year outcomes. Results: Overall, 15,423 Medicare beneficiaries underwent AF ablation (mean age 72 years, 41% female and 96% white). Common comorbidities included hypertension (78%) and ischemic heart disease (51%). Dementia (0.6%) and stroke/TIA (6%) were relatively rare. Adverse outcomes at 30 days were fairly infrequent, including death (0.8%), stroke/TIA (0.8%), pericardial effusion (2%), MI (0.3%) and vascular complications (0.5%). Within 1 year, 4% of patients died, 43% required new hospitalization, and 11% had repeat ablation. AF or atrial flutter was the primary discharge diagnosis in a minority of new hospitalizations (38%). The death rate among patients aged ≥80 years (10%) was 5 times higher than among patients aged 65-69 years (2%). Whereas stroke/TIA, heart failure and hospitalization (Figure) also increased with age, repeat ablation was more common in younger patients. After multivariable adjustment, renal impairment (HR 2.07 [1.66, 2.58]), advanced age (HR for age ≥ 80 years, =3.09 [2.32, 4.11]), and heart failure (HR 2.54 [2.07, 3.13]) were notable risk factors for 1-year mortality following AF ablation. Conclusion: While major complications following AF ablation were fairly infrequent, new hospitalization was common. Given the association of complications and death with increasing age, randomized trials should inform the risk-benefit of AF ablation for elderly patients.