Practice Patterns of Antiplatelet and Anticoagulant Therapy After Fenestrated/Branched Endovascular Aortic Repair

Objective Antiplatelet and/or anticoagulant therapy are commonly prescribed after fenestrated/branched endovascular aortic repair (F/BEVAR). However, the optimal regimen remains unknown. We sought to characterize practice patterns and outcomes of antiplatelet and anticoagulant use in patients who underwent F/BEVAR. Methods Consecutive patients enrolled (2012-2023) as part of the United States Aortic Research Consortium (US-ARC) from ten independent physician-sponsored investigational device exemption (PS-IDE) studies were evaluated. The cohort was characterized by medication regimen on discharge from index F/BEVAR: 1. Aspirin alone OR p2y12 alone (single-antiplatelet therapy, SAPT), 2. Anticoagulant Alone, 3. Aspirin+p2y12 (dual-antiplatelet therapy, DAPT), 4. Aspirin+anticoagulant OR p2y12+anticoagulant (SAPT+Anticoagulant), 5. Aspirin+p2y12+anticoagulant (triple therapy, TT), and 6. No Therapy. Kaplan-Meier analysis and Cox proportional hazards modeling were used to compare 1-year outcomes including survival, target artery patency, freedom from bleeding complication, freedom from all reinterventions, and freedom from stent-specific reintervention. Results Of the 1525 patients with complete exposure and outcome data, 49.6% were discharged on DAPT, 28.8% on SAPT, 13.6% on SAPT+Anticoagulant, 3.2% on TT, 2.6% on Anticoagulant Alone, and 2.2% on No Therapy. Discharge medication regimen was not associated with differences in 1-year survival, bleeding complications, composite reintervention rate, or stent-specific reintervention rate. However, there was a significant difference in 1-year target artery patency. On multivariable analysis comparing to SAPT, DAPT conferred a lower hazard of loss of target artery patency (HR 0.48, 95% CI 0.27-0.84, p=0.01). On sub-analyses of renal stents alone or visceral stents alone, DAPT no longer had a significantly lower hazard of loss of target artery patency (Renal: HR 0.66, 95% CI 0.35-1.27, p=0.22. Visceral: HR 0.31, 95% 0.05-1.9, p=0.21). Lastly, duration of DAPT therapy (1 month, 6 months, or 1 year) did not significantly affect target artery patency. Conclusions Practice patterns for antiplatelet and anticoagulant regimens after F/BEVAR vary widely across the US-ARC. There were no differences in bleeding complications, survival or reintervention rates among different regimens, but higher branch vessel patency was noted in the DAPT cohort. These data suggest there is a benefit in DAPT therapy. However, the generalizability of this finding is limited by the retrospective nature of this data, and the clinical significance of this finding is unclear, as there is no difference in survival, bleeding, or reintervention rates amongst the different regimens. Hence, an “optimal” regimen, including the duration of such regimen, could not be clearly discerned. This suggests equipoise for a randomized trial, nested within this cohort, to identify the most effective antiplatelet/anticoagulant regimen for the growing number of patients being treated globally with F/BEVAR.