Hereditary/Acquired Bleeding Disorders

Currently there are no specific guidelines for the treatment of atrial fibrillation (AF) in patients with von Willebrand disease (VWD). Using electronic medical records from a 40-year period (AF diagnosis dates ranging from 1980 to 2020), investigators from Brigham and Women's Hospital, Boston, conducted a retrospective observational study to evaluate the rate of major bleeding (as defined by ISTH criteria) in VWD patients undergoing anticoagulation (AC) or antiplatelet (AP) therapy for AF. The study (abstract 590) was reported at the 63rd Annual Meeting of the American Society of Hematology (ASH). A total of 340 patients met the evaluation criteria (diagnosis of VWD, low ristocetin cofactor level, or any abnormal VWF panel plus a diagnosis of AF or atrial flutter); 89 (64% female) were included in the analysis. Among VWD patients treated with AC alone, the rate of major bleeding was 8.9 events per 100 person-years and among those treated with AP alone was 10.2 events per 100 person-years (P=.572). Among VWD patients never prescribed AC or AP, the rate of major bleeding events was 1.06 events per 100 person-years (P<.0001). "Notably," the investigators reported, "the rate of major bleeding on AC and AP together was 28.07 events per 100 person-years (P<.0001) occurring in 7 patients, 6 of whom also had a diagnosis of acute coronary syndrome (ACS)." While acknowledging that their analysis was limited by its retrospective nature and a lack of certain clinical details in the older charts, the researchers advocated shared decision-making around stroke and bleeding risk when considering AC use for AF in patients with VWD. Prospective studies are warranted, they said, to "evaluate the risk of major bleeding and stroke in patients with VWD and AF on standard AC vs no AC."