Atrial Fibrillation Management in Cardiac Amyloidosis: A Single-Center Experience

Abstract 2316230, presented at Western Atrial Fibrillation Symposium 2026

Atrial fibrillation (AF) is a hallmark arrhythmia in transthyretin cardiac amyloidosis (ATTR-CM), seen in up to 70% of patients. Rhythm-control strategies in ATTR-CM reflect those for general populations, and freedom from atrial arrhythmias following catheter ablation are thought to be much lower. Furthermore, outcomes of rhythm control strategies are less well defined in the era of disease-modifying therapies for ATTR-CM. We performed this study to quantify the burden of AF in ATTR-CM, explore durability of catheter ablation and its impact on mortality and assess the impact of disease-modifying therapies on arrhythmia outcomes .We retrospectively identified consecutive ATTR-CM patients who underwent AF ablation at a tertiary referral center between 2010-2024 with >6 months follow up. AF/AT recurrence was assessed after a 60-day blanking period. Outcomes were collected with individual EHR review. Arrhythmia recurrence and mortality were assessed using Kaplan Meier analysis and multivariable Cox regression, adjusting for age, disease severity, and ATTR-directed therapy.In 237 patients with ATTR-CM (mean age 75.9 ± 8.6 years, 91.6% male), AF was present in 133 individuals (56.1%) preceding diagnosis of ATTR and 66 patients (27.8%) developed AF a median of 14 months [IQR 30 months] following ATTR-CM diagnosis. AF catheter ablation was performed in 41 patients and 37 had >6 months of follow-up. Procedural complications were rare, with only one case of cardiogenic shock. Freedom from atrial arrhythmias was 51% at 1 year and 27% at 5 years. Patients with recurrence had larger left atrial volume (49.2 vs 31.9 mL, p = 0.03) and lower left ventricular ejection fraction (49.5% vs 63.5%, p = 0.03). During follow-up, 8 of 37 patients (22%) died, median 86 months [IQR 18 months] after ablation. Among 158 patient who did not undergo AF ablation, 50 (31.6%) died, median 38 months [IQR 35 months] from ATTR diagnosis. In an exploratory comparison, catheter ablation was associated with reduced all-cause mortality (HR 0.47, 95% CI 0.23–0.98, p = 0.041). However, after adjustment for age, the association was attenuated and no longer statistically significant (HR 0.62, p=0.15).AF in ATTR-CM is highly prevalent and independently associated with worse outcomes. Catheter ablation offers superior rhythm durability with acceptable procedural risk, particularly in patients with less advanced remodeling.