Impact of Single Antiplatelet, Dual Antiplatelet, and Anticoagulation Plus Antiplatelet Therapy on Branch Vessel Patency and Bleeding Risk Following Branched Endovascular Aortic Repair

Purpose: To compare the effects of single antiplatelet (SAPT), dual antiplatelet (DAPT), and anticoagulation plus antiplatelet (AC + AP) therapies on branch vessel patency and bleeding risk after branched endovascular aortic repair (B-EVAR). Methods: This single-center retrospective cohort study included 250 patients with 880 target branches who underwent B-EVAR (2015–2025). Primary outcomes were branch patency loss (occlusion/stenosis requiring reintervention) and major bleeding (ISTH criteria). Propensity score weighting and competing risk regression controlled confounding. Results: During median 18-month follow-up, 82 branches (9.3%) lost patency: 12.0% (SAPT), 7.0% (DAPT), 7.5% (AC + AP). DAPT significantly improved patency vs. SAPT (sHR 0.72, p = 0.045). Major bleeding occurred in 22 patients (8.8%): 4.4% (SAPT), 7.5% (DAPT), 22.5% (AC + AP). AC + AP tripled bleeding risk (HR 3.10, p = 0.001); DAPT showed non-significant trend (HR 1.62, p = 0.13). Conclusion: DAPT provided the most favorable balance between branch vessel patency and major bleeding after B-EVAR. AC + AP was associated with substantially higher bleeding and should be reserved for patients with an independent indication for anticoagulation. Taken together with prior multicenter European and US consortium data, these findings support a class IB-level preference for DAPT in patients without competing anticoagulation needs; prospective randomized multicenter trials are needed to support a class IA recommendation.