Management of dual antiplatelet therapy following covered femoropopliteal stenting - Why size matters.

Background: Endovascular therapy has emerged as an effective minimally invasive approach for treating peripheral artery disease (PAD). Postprocedural dual antiplatelet therapy (DAPT) is commonly used to prevent adverse events, but optimal management remains uncertain. Patients and methods: This international, multicentre retrospective study synthesized data from three studies on covered stents (VIABAHN^® Endoprosthesis) in 437 PAD patients (2001-2015). A dimension index (total stent length/smallest diameter) was developed and externally validated in a second cohort (n=148). Results: Among 321 patients with DAPT, univariate analysis showed no association between the initiation of DAPT and reduced major adverse limb events (MALE). Longer total covered length (aHR: 1.02) and smoking (aHR: 1.43) were associated with increased MALE, while stent diameters of 7-8mm showed a protective effect (aHR: 0.30). Cox proportional hazards models repeatedly showed that both the duration of DAPT and the dimension index (total covered length/smallest stent-graft diameter) were significantly associated with MALE after adjusting for other confounders. However, in a sensitivity analyses, no significant impact of DAPT on MALE was observed in patients with a high dimension index. Conclusions: These findings suggest while longer DAPT strategies might be protective towards MALE, stent-graft properties might be at least as relevant if not more determining regarding impaired outcomes after femoropopliteal interventions. Individualizing DAPT duration based on stent proportions might offer further opportunities for optimized protocols by personalized pharmacological therapies.