Impact of Postoperative Antithrombotic Treatment on Patency and Survival After Open Posterior Popliteal Artery Aneurysm Repair: A Multicenter Retrospective Cohort Analysis from the PARADE Study

Background/Objectives: This study assessed the impact of different postoperative antithrombotic strategies on graft patency and overall survival after open posterior repair of popliteal artery aneurysms (PAAs). Methods: A retrospectively maintained dataset of consecutive PAAs electively treated in 40 centers between January 2010 and December 2023 was analyzed. The study included patients undergoing elective open posterior repair. Primary outcomes were primary patency and overall survival according to postoperative antiplatelet or anticoagulant therapy. Secondary outcomes included secondary patency and major adverse cardiovascular events (MACEs). Kaplan–Meier analysis, log-rank testing, and Cox regression models were applied. Results: Overall, 638 patients were included. The cohort was predominantly male (96%), with a median age of 70 years. At 30 days, one death (0.2%) and seven MACEs (1.1%) occurred. Postoperative therapy was not associated with 30-day primary patency or MACEs. At a median follow-up of 30 months, overall survival was 90.3%. Kaplan–Meier analysis showed comparable overall survival across antithrombotic regimens, with a significant difference observed only between patients receiving combined anticoagulant and antiplatelet therapy and those receiving other regimens (p = 0.018). No differences emerged between vitamin K antagonists (VKAs) and direct oral anticoagulants (DOACs), nor between single or dual antiplatelet therapy and anticoagulation. Multivariable Cox regression showed that combined therapy was associated with poorer overall survival compared with other postoperative antithrombotic regimens (CT vs. others: HR of 1.30). Primary and secondary patency were also similar among regimens except for combined therapy (primary patency: p = 0.004; secondary patency: p = 0.018). Conclusions: Postoperative medical therapy was not associated with 30-day outcomes. During long-term follow-up, overall survival and graft patency were lower in patients receiving combined anticoagulant and antiplatelet therapy. Bleeding outcomes were not captured in this registry; as bleeding may contribute to the worse outcomes observed with combined therapy, this represents an important limitation.