Abstract 15368: Outcomes of Anticoagulation in Patients With Transthyretin Cardiac Amyloidosis

Introduction: Up to 70% of patients with transthyretin amyloid cardiomyopathy (ATTR-CM) have (AF) and require anticoagulation (AC). ATTR-CM is also associated with a higher bleeding risk due to advanced age, frailty, and comorbidities. Prior studies have shown that thrombi can be seen in any chamber of the heart. In the era of left atrial appendage occlusion (LAAO) devices, a reappraisal of AC outcomes in ATTR-CM is needed. Hypothesis: AC in patients with ATTR-CM is not associated with significantly different rate of bleeding as compared to patients who are not on AC. Methods: This observational study was performed on a single center of ATTR-CM patients (n=149) diagnosed between 2005-2022. Bleeding outcomes were stratified according to AF and AC status. The primary outcome was defined as a composite of all major bleeding. Bleeding episodes were further categorized into correctable or uncorrectable. HASBLED scores for each patient were also calculated. Results: Of the 149 patients reviewed, 94 (63%) had AF and 95 (64%) were on AC. In the overall population, 20 patients (13%) experienced a bleeding episode, with 30% (6 /20) of the episodes classified as uncorrectable requiring indefinite AC cessation. During a medium (IQR) of 3.1 (2.6,4.9) years of follow-up, there was no significant difference in bleeding between those who were on AC compared to those who were not on AC (P = 0.105). There was also no significant difference in bleeding between those who had atrial fibrillation and those who did not (P = 0.464). Patients who experienced a bleeding episode had a significantly higher average HASBLED score compared to those who did not experience a bleed (2.7 vs 1.7, P<0.01) In total, 5 (5%) of ATTR-CM patients with AF would have been candidates for LAAO devices. Conclusions: AC is not associated with significantly increased risk of bleeding in patients with ATTR-CM compared to those who were not on AC. HASBLED scores may be useful in ATTR-CM. While further studies are needed to study the outcomes of LAAO devices in ATTR-CM, the incidence of requiring such an intervention in ATTR-CM appears to be low.