Evaluation of bleeding events in a cohort of patients with transthyretin cardiac amyloidosis

Abstract Introduction and purpose transthyretin amyloidosis is an infiltrative disease with several comorbidities, including bleeding. The aim of this study was to evaluate the incidence of bleeding in patients with transthyretin amyloidosis and the underlying risk factors that promote bleeding. Methods a retrospective observational study was conducted on a cohort of patients with transthyretin amyloidosis diagnosed between 2016 and 2023 according to the diagnostic criteria of the Working Group on Myocardial and Pericardial Diseases of the European Society of Cardiology. Bleeding risk was calculated according to HAS-BLED score and bleeding events at follow-up were analysed. Results 184 patients were diagnosed with a median age of 84 years [IQR 79-8], 154 (8%) males. 123 patients (67%) were on anticoagulant therapy. 91 patients (50%) had a bleeding event, with a total of 189 events recorded and a median time from transthyretin amyloidosis diagnosis to bleeding of 10 months [IQR 6-14]. The most frequent bleeding sites were gastrointestinal (32%) and cutaneous (22%). 35 patients (39%) had a haemorrhage which fulfilled severe bleeding criteria and 4 patients died of haemorrhagic causes. As a consequence of bleeding, 6 atrial appendage closure were indicated and anticoagulation therapy was modified in 15 individuals. The incidence rate of haemorrhage was 50 bleeds per 100 patient-years and 58 per 100 patient-years in patients on anticoagulant treatment. Anticoagulant therapy resulted in a 3,5-fold raise in bleeding (95% CI 2-7) and a punctuation ≥2 in HAS-BLED score increased haemorrhages 4,6 times (95% CI 2-9), with higher rates of bleeding the higher the score on the scale. Conclusions bleeding is a frequent complication in transthyretin amyloidosis, with a higher risk in those individuals with anticoagulant therapy or with a HAS-BLED score ≥2. Subsequently, it should be considered in the follow-up both haemorrhagic risk and anticoagulant treatment, with the aim of implementing strategies to reduce the bleeding risk.