Bypass versus endovascular treatment for occluded femoro-popliteal stents in patients with critical limb-threatening ischemia

Objectives: the aim of the study was to compare the early and medium-term outcomes of bypass versus endovascular treatment of occluded femoro-popliteal stents in patients with chronic limb-threatening ischemia (CLTI) (the OUT-STEPP2 multicentric registry). Methods: between January 2016 and December 2021 317 patients in 14 centers underwent treatment for a symptomatic occlusion of femoro-popliteal stent/stents. One-hundred-sixty-one patients were included into the present study: 46 (28.6%) underwent open bypass surgery (Group OPEN), and 115 (71.4%) underwent endovascular revascularization (Group ENDO). Early (30 days) results were assessed and compared between the two groups. Estimated 5-year outcomes were evaluated and compared with the log-rank test. Results: at 30 days no differences were found in terms of Major Adverse Cardiovascular Events (MACE), Acute Kidney Injury (AKI), reinterventions, major amputation, and all-cause mortality between the two groups. The need for blood transfusions was higher for patients in Group OPEN (17, 36.9% vs. 13, 11.3%; p<0.001). The mean length of Intensive Care Unit (ICU) stay and the mean hospital stay were higher for patients in Group OPEN [(0.3 ± 0.9 vs. 0; p<0.001) and (9.7 ± 5.8 vs. 3.3 ± 1.4 days; p<0.001), respectively]. The overall median duration of follow-up was 33.1 (IQR 14-49.5) months. At 5 years there were no differences between the two groups in terms of survival (68.7% Group OPEN vs. 68.8% Group ENDO; p=0.27, log-rank 1.21), primary patency (56.3% Group OPEN vs. 67.8% Group ENDO; p=0.39, log-rank 0.75), secondary patency (59.1% Group OPEN vs. 77.8% Group ENDO; p=0.24, log-rank 1.40), absence of target lesion restenosis (56.8% Group OPEN vs. 62.7% Group ENDO; p=0.42, log-rank 0.65), and limb salvage (77.2% Group OPEN vs. 90.4% Group ENDO; p=0.17, log-rank 1.87). Conclusions: both bypass and endovascular treatment provided safe and effective restoration of patency for femoro-popliteal in-stent occlusion in CLTI patients. Open surgery was associated with longer stay in hospital and increased use of blood transfusions. At five-years, no significant differences were found in the rates of overall patency or limb salvage between bypass and endovascular treatment.