Abstract 14362: The Columbia Score Predicts Incident Atrial Fibrillation and Flutter in Patients With Transthyretin Cardiac Amyloidosis

Abstract

Introduction: Atrial fibrillation/flutter (AF) is common in transthyretin cardiac amyloidosis (ATTR-CA). Given the high risk of systemic embolism, there is growing interest in the role of clinical scores for predicting new onset AF in affected patients to potentially guide early prevention of thromboembolic events. The CHARGE-AF scoring system was previously derived from the general population, but has not been validated in ATTR-CA. The Columbia staging system for ATTR-CA is prognostic for survival, but its utility in predicting incident AF is unknown. This study explored the incidence rate and risk scores for AF in ATTR-CA. Methods: This is a retrospective cohort study of 175 patients diagnosed with ATTR-CA who did not have any prior AF upon initial evaluation. We compared the baseline clinical characteristics of individuals with and without incident AF during subsequent follow-up. AF was ascertained based on review of electrocardiograms, continuous monitoring when available, device interrogations if applicable, and charted history. The Columbia score for amyloidosis staging was computed from: Gilmore stage + daily furosemide dose equivalents (0 points: 0 mg/kg, 1 point: between >0 to 0.5 mg/kg, 2 points: >0.5 to 1 mg/kg, 3 points: >1 mg/kg) + NYHA functional class. Time to event analysis was performed via Cox proportional hazard modeling to determine the factors associated with incident AF. Results: New onset AF developed in 41% (n=71) of ATTR-CA patients, with a median follow-up of 2.0 years for the overall population. Compared to those without incident AF, more patients with incident AF were males (93.0% vs 78.8%); self-identified as white race (78.9% vs 61.5%); and reported NYHA II-IV symptoms (91.5% vs 78.8%); but were less frequently of Hispanic ethnicity (2.8% vs 10.6%) or had a genetic variant (25.4% vs 49.0%), all p<0.05. On multivariable analysis, per point increase in Columbia score (HR 1.21, 95% CI 1.03-1.42, p=0.018) was associated with new onset AF, but gender, variant disease, CHARGE-AF, and left atrial volume index were not. Conclusions: About half of ATTR-CM patients developed incident AF during follow-up, which was predicted by the Columbia score, but not the CHARGE-AF score.