Abstract 18515: Prevalence of Right and Left Atrium Non-Pulmonary Vein Triggers in Cardiac Amyloidosis Patients Undergoing Atrial Fibrillation Ablation

Abstract

Introduction: Cardiac amyloidosis (CA) has been associated with an increased risk of atrial arrhythmias due to infiltration of the amyloid protein in the atrial wall. Though non-pulmonary vein(PV) triggers are commonly seen in left atrium, they are also seen in the right side of the heart, so identifying them at the time of ablation is essential. Minimal data exists on the prevalence of triggers in amyloidosis patients. Aim: The study evaluates the prevalence of non-PV triggers during catheter ablation in atrial fibrillation (AF) patients affected by cardiac amyloidosis Methods: This is a study including 74 consecutive patients with an established diagnosis of amyloidosis ATTR diagnosed with cardiac MRI or myocardial biopsy that underwent their first AF catheter ablation. They underwent PV isolation + isolation of left atrial posterior wall and superior vena cava. Additionally, extrapulmonary triggers, which are defined as ectopic triggers originating from sites other than PVs including left atrial appendage (LAA), coronary sinus (CS), interatrial septum, crista terminalis, mitral valve anulus were identified and ablation in all 74 patients. Post procedure, patients were followed up routinely with ECG during office visits, 7-day Holter monitor and event recorders for the duration of 1 year. Results: Isoproterenol-challenge revealed non-PV triggers in 51 (68.9%) patients. These triggers were mostly mapped to LAA (39, 52.7%), CS (30, 40,5%), and crista terminalis (35, 47.3%). Besides, ectopic beats were seen originating from inter-atrial septum (19, 25.6%), mitral valve annulus (10, 13.5%). More than one trigger was found in (68%) patients.At 1-year after the ablation, 65 (87.8%) were arrhythmia-free off AADs. Conclusions: Our findings suggest that non-PV triggers are highly prevalent in cardiac amyloidosis AF patients including a much higher rate crista terminalis firing compared to the standard population.