PB0834 - Antiplatelet Use and Outcomes Among Patients with Acute Coronary Syndrome and von Willebrand Disease

Background: People with von Willebrand disease (VWD) are advised to avoid antiplatelet therapies. However, treatment for the acute coronary syndrome (ACS) includes aspirin (ASA), P2Y12 inhibitors, dual antiplatelet therapy (DAPT), and/or anticoagulation (AC).

Aims: This study assessed the efficacy and safety of antiplatelet use in patients with VWD and ACS.

Methods: Coded data from institutional electronic medical records identified subjects with VWD or any abnormal VWF panel as well as ACS. Of 512 initially identified, 55 were included in the analysis after manual screening. Primary endpoint was rate of ISTH major bleeding while prescribed antiplatelet therapy.

Results: Demographic data and prescribing patterns are shown in Table 1. 38.2% (21/55) had stents placed via PCI and 25.5% (14/55) underwent coronary artery bypass grafting (CABG). After percutaneous coronary intervention (PCI), 81% (17/21) initiated DAPT. 71.4% (15/21) were prescribed DAPT for at least 28 days and 28.6% (6/21) for at least one year. Median ASA use was 10.1 years (IQR: 3.5-16.3) and 0.08 years (IQR: 0.08-3.18) for DAPT. One patient had a major bleed on DAPT (1/23; 4.3%). 26.5% (9/34) of patients prescribed ASA alone had a bleeding event, but only 2 events (5.9%) occurred in the first year. Figure 1 shows time to first major bleed while prescribed ASA.

Conclusion(s): In patients with VWD and ACS, a majority (83.6%) received ASA, and 71.4% received at least 4 weeks of DAPT after PCI with only 5.9% on ASA monotherapy experiencing bleeding in the first year, but over a quarter experienced bleeding with longer use. This analysis is limited by its retrospective nature and lack of granular details in the database. Shared decision-making regarding bleeding risk and cardiac protection is advised. Our data suggest that short-course DAPT is relatively safe in patients with VWD, but long-term ASA should be approached with caution.