580 INCIDENCE AND FACTORS ASSOCIATED WITH DE NOVO ATRIAL FIBRILLATION IN PATIENTS WITH WILD-TYPE TRANSTHYRETIN CARDIAC AMYLOIDOSIS - A MULTICENTER STUDY


 
 
 We described the incidence and ECG factors associated with de novo atrial fibrillation (AF) in patients diagnosed with wild-type transthyretin cardiac amyloidosis (ATTRwt-CA) to drive tailored arrhythmia screening.
 
 
 
 Data on the incidence rate and factors associated with de novo AF in patients with ATTRwt CA is limited.
 
 
 
 Multicenter, retrospective, observational cohort study performed in six referral centers for CA. All consecutive patients diagnosed with ATTRwt-CA between 2004 and 2020 with >1-year follow up (FU) were enrolled in the study and were divided into three groups according to presence of AF: (1)patients with ‘known AF’; (2)patients in ‘sinus rhythm’ and (3)patients developing ‘de novo AF’ during FU. Incidence and factors associated with AF in patients with ATTRwt were the primary outcomes.
 
 
 
 Overall, 266 patients were followed for a median of 469 days: 148 (56%) with known AF, 84 (31.6%) with sinus rhythm, and 34 (12.8%) with de novo AF. Age and gender were similarly distributed. At multivariable analysis, PR (Hazard Ratio[HR]: 1.008 95% C.I. 1.001-1.016), QRS (HR: 1.022 95% C.I. 1.002-1.043) and left atrial dilatation>50mm (HR: 3.429 95% C.I. 1.565-7.329) were associated with de novo AF at FU. Patients presenting with at least two risk factors (PR>200ms, QRS>120ms or LAD>50mm) had a higher risk of developing de novo AF compared to patients with no risk factors (HR 14.918 95% C.I. 3.242-31.646).
 
 
 
 Incidence of de novo AF in patients with ATTRwt is 20.7%/year. Longer PR and QRS duration and left atrial dilation are associated with arrhythmia onset.
