Background: Atrial fibrillation (AF) is common in patients with transthyretin cardiac amyloidosis (ATTR-CA), occurring in approximately 70%. Patients with ATTR-CA have higher frailty scores and are at increased risk for falls due to autonomic dysfunction which may increase bleeding risk.
Objective: To investigate rates of bleeding requiring cessation of anticoagulant (AC) therapy in patients with ATTR-CA.
Methods: This was a retrospective cohort study of 265 consecutive patients with ATTR-CA and AF at our institution. Patients were followed for 33±25 months.
Results: Baseline characteristics are shown in Figure 1a. Mean HAS-BLED score was 2.2±0.9 and mean CHADS-VASc was 3.8±1.4. Anticoagulation was withheld in 15/265 (6%) patients. Among the 250 patients who were started on AC, warfarin was used in 160 (60%), apixaban was used in 51 (19%), rivaroxaban in 28 (11%) and dabigatran in 11 (4%). During follow-up, AC was stopped in 80 (30%) patients due to bleeding and 9 (4%) due to frailty or falls. Bleeding occurred in 59 (37%) on warfarin, 6 (12%) on apixaban, 9 (32%) who were taking rivaroxaban and 4 (36%) who were on dabigatran (p=0.009). Cardioembolic stroke occurred in 28 (27%) in whom AC was withheld/stopped compared to 16 (10%) in whom AC was continued (Figure 1b, p=0.009). Higher HAS-BLED score was associated with higher rates of bleeding (Figure 1c, p<0.001).
Conclusion: Bleeding requiring cessation of anticoagulation is common in patients with ATTR-CA and is associated with higher rates of cardioembolic stroke. Patients with ATTR-CA on AC for AF should be closely monitored for bleeding and earlier consideration of left atrial appendage occlusion devices may be warranted.