Incidence of Acute Thrombotic Occlusion and Its Predictors After Contemporary Femoropopliteal Endovascular Therapy in Patients With Peripheral Artery Disease

Purpose: This study investigated the incidence of acute thrombotic occlusion (ATO) and its predictors after contemporary femoropopliteal (FP) endovascular therapy (EVT) for peripheral artery disease. Materials and Methods: We retrospectively examined 763 limbs (chronic limb-threatening ischemia [CLTI]: 44%, involving popliteal lesion: 44%) in 644 patients (mean age: 75±9 years, male: 71%, hemodialysis: 34%) who successfully underwent EVT with contemporary FP devices (drug-coated stent: n=220, stent graft: n=158, drug-eluting stent: n=150, drug-coated balloon [DCB]: n=235) from June 2012 to July 2020. The outcome measure was ATO defined as acute onset of claudication and/or signs of CLTI in combination with angiographic evidence of occlusive thrombus formation within the treated segment. Cox proportional hazards regression models were used to identify baseline characteristics associated with the incidence of ATO after EVT treated with scaffold. To determine the impact of ATO occurrence and creatine phosphokinase (CPK) elevation on the subsequent composite outcome of mortality or major amputation, we developed the Cox model in which the trichotomous variable (free from ATO, ATO without CPK elevation, and ATO with CPK elevation) was a time-dependent covariate. Results: The 24-month incidence of ATO in the overall population was 4.3%±0.8% (DCB: 1.0%±0.7% vs scaffold: 5.8%±1.1%, p<0.01). Hemodialysis (hazard ratio [HR]: 2.63, p=0.02) and involving popliteal lesion (HR: 8.22, p<0.01) were independently associated with an increased risk of ATO in patients treated with scaffold. Both ATO without CPK elevation and ATO with CPK elevation were significantly associated with a composite outcome of mortality or major amputation comparing free from ATO, with an HR of 2.39 and 9.87, respectively (p=0.02 and p<0.01). Conclusion: We found a substantial incidence of ATO after contemporary FP-EVT, particularly with scaffold. Hemodialysis and involving popliteal lesion were significantly associated with ATO risk in patients treated with scaffold. The occurrence of ATO, particularly with CPK elevation, was associated with an increased risk of a subsequent composite outcome of mortality or major amputation. The scaffold was safely used in patients without those risk factors of ATO, but a non-scaffolding strategy should be considered for patients with more risk factors. Clinical Impact The scaffold was safely used in patients without hemodialysis and involving popliteal lesion, but a non-scaffolding strategy should be considered for patients with those risk factors. The occurrence of ATO, particulary with CPK elevation, was of high risk of mortality or amputation.