(PC044) Antithrombotic Therapy in Patients with Isolated Peripheral Arterial Disease Undergoing Peripheral Vascular Interventions

Objectives: Comorbidities and procedural history can significantly influence the choice of antithrombotic therapy in patients undergoing peripheral vascular interventions (PVI) for peripheral arterial disease (PAD). The landscape of antithrombotic therapy is growing in complexity with paucity of trials dedicated to patients with PAD. This study assesses antithrombotic regimens in patients presenting with isolated PAD, without other comorbidities or procedural history that could affect antithrombotic management.

Methods: The Vascular Quality Initiative (VQI) PVI database was reviewed. Only patients with isolated PAD without history of cardiovascular or cerebrovascular disease, or other indications for antithrombotic therapy were included. Patients presenting with acute limb ischemia or chronic anticoagulation preoperatively were excluded. The characteristics and outcomes of patients discharged on factor Xa inhibitor plus single antiplatelet therapy (FXaI+SAPT) were compared to patients discharged on dual antiplatelet therapy (DAPT).

Results: A total of 191,421 patients underwent PVI and 60% of patients were excluded because of competing indications for antithrombotic therapy. Isolated PAD constituted only 40% of the sample (N=75,334) and exhibited extensive variations in the medications prescribed at discharge, totaling 40 unique combinations. The most common class combinations were DAPT (Aspirin+P2Y12i) was used in 59% of patients, followed by SAPT (Aspirin or P2Y12i) in 30%, FXaI+SAPT in 2.6%, and 5.5% were discharged without antithrombotic medication. Patients received FXaI+SAPT (N=1,914) were more likely to be younger (65 vs. 67;P < 0.001) and African American (20% vs. 18%; P< 0.001) compared to patients received DAPT (N=43,807) but were less likely to have diabetes (40% vs. 46%;P < 0.001), and chronic kidney disease (63% vs. 70%; P< 0.001). Patients discharged on FXaI+SAPT were more likely to be treated for chronic limb-threatening ischemia compared to patients discharged on DAPT (71% vs. 52%;P < 0.001).
After 3:1 propensity matching, there were 5,890 patients included in the analysis with no differences in baseline characteristics (Table).
Patients received FXaI+SAPT had higher rates of thrombosis and embolism postoperatively and were less likely to be discharged home. Patients received FXaI+SAPT had higher rates of long-term reintervention and major amputation (Table). Kaplan-Meier curves showed a significantly lower overall survival, freedom from amputation, and MALE-free survival for patients receiving FXaI+SAPT compared to patients receiving DAPT upon discharge (Figure).

Conclusions: Most patients with PAD undergoing PVI have competing indications for antithrombotic therapy. There is a wide variation in the antithrombotic regimens of patients with isolated PAD. DAPT seemed to be associated with better long-term outcomes compared to FXaI+SAPT for patients with isolated PAD undergoing PVI.