This study is a prospective, multicenter, real world, observational study intended to understand the impact of tibial run off on clinical outcome of endovascular therapy in Femoropopliteal lesions. It is estimated that 1200 patients with chronic femoral popliteal artery occlusion were enrolled in the group at 8 centers nationwide from January 2021 to December 2022. Two groups would be divided according to whether or not the tibial run off intervened for reconstruction. The intervention group and the non-intervention group. The intervention group would be evaluated Run-off score again after the tibial run off reconstructed. The the Society for Vascular Surgery(SVS) run-off score would be used for the score of the tibial run off. The total score of the tibial run off would be 19 points, 1 point indicating healthy run off. According to the quality of the run off, the preoperative patients would be divided into 1-5, 6-10, 11-15, and >15 points. The follow-up would be conducted at 1, 6, 12, 18 and 24 months after the operation. As it is a real world study, there is no determined end point.The main indicators would be observed including the reintervention rate driven by lesions' clinical symptoms, the rate of primary patency of the femoral popliteal artery, the improvement of quality of life score and rutherford grading.

Arteriosclerosis obliterans of lower extremities (arteriosclerosis obliterans, ASO) is a common and frequently-occurring disease in middle-aged and elderly people, and also an important manifestation of atherosclerosis in lower extremities.ASO is reported to be present in approximately 12%-14% of the population, increasing to 20% of the population over the age of 75.The current treatment methods of ASO include pharmacotherapy, surgical procedures, endovascular treatment, combined surgery, and autologous peripheral blood stem cell transplantation (ASCT), etc.Endovascular treatment of ASO for lower limbs has the advantages of safety, effectiveness and fewer complications, and has become the preferred treatment for ASO.Endovascular treatment mainly includes: percutaneous transluminal angioplasty (PTA) and bare stent implantation. Currently, the most commonly used surgical options include: ordinary balloon dilatation + drug-coated balloon (DCB) dilatation + bare stent implantation.A number of studies have proved that DCB and bare stent are more effective than common PTA, but postoperative restenosis in ASO is always a difficulty.In addition to the chronic total occlusion or diffuse lesion of the lower extremity arteries, the inferior genicular artery outflow channel, age, diabetes, hemodialysis and critical limb ischemia are all related.Matsumi J, et al. found that patency of the inferior genicular artery may be an important predictor of adverse events after the SMART stent implantation in patients with popliteal artery disease, and the preservation of the distal outflow tract may be beneficial to reduce the rate of restenosis Early analysis of the patency rate of inferior genicular artery bypass found that poor outflow tract could lead to an increase in bypass thrombosis events.Matsumi J,et al. found that patency of the Early analysis of the patency rate of inferior genicular artery bypass found that poor outflow tract could lead to an increase in bypass thrombosis events. may be an important predictor of adverse events after SMART stent implantation in patients with popliteal artery disease, and the preservation of the distal outflow tract may be beneficial to reduce the rate of restenosis.Daniel M et al. conducted a retrospective analysis of 95 patients with femoral popliteal artery stent implantation and found that,for patients with poor subgenual artery outflow tract, the number of additional inferior genicular artery during femoral artery stent implantation usually leads to better clinical outcomes.the number of inferior genicular artery shown by preoperative angiography is an independent predictor of post-stent clinical outcomes.This study demonstrates the importance of distal outflow tract clinical outcomes after stent implantation.Yusuke W,et al. conducted a retrospective study on 199 patients with chronic popliteal artery occlusion and found that additional inferior genicular artery opening during stent implantation was beneficial to the patency rate of the stent and clinical results .However, the current analysis of the influence of the tibial run off on the femoral popliteal patency is mainly a retrospective study.

The purpose is to evaluate the patency of the tibial run off through a prospective multicenter observational real world study, whether it has an impact on the therapeutic effect after endovascular treatment in femoral popliteal artery , and whether one-stage reconstruction of the tibial run off can improve the postoperative patency rate of endovascular treatment.

Inclusion Criteria:

• 1) Rutherford stages 2-5. 2) The femoral and popliteal artery as the target of the study has at least ≥70% stenosis or occlusion.

  3) Whether it is a primary femoral and popliteal artery disease or in-stent restenosis, patients who received endovascular recanalization successfully (Residual stenosis <30% and no flow-limiting arterial dissection) can be enrolled in the group.

  4) For the patients with both lower limbs to be treated, both limbs can be selected into the group.

  5) Patients who failed the first treatment because the guide wire could not pass through the lesion can still be included in the group after successful endovascular interventional treatment.

  6) Patients who understand the purpose of this research, volunteer to participate in the experiment, sign an informed consent form and are willing to be followed up can be included in the experiment.

  7) For ipsilateral aortoiliac artery disease, patients with residual stenosis <30% can also be included in the group after intravascular reconstruction.

Exclusion Criteria:

• 1) Patients with acute arterial thrombosis. 2) Patients with serum creatinine level> 176μmol/L. 3) Patients with Rutherford stage 5 have foot infection grades of 2 and 3 in the preoperative WIFI (WIfI) classification.

  4) Limbs that have been treated with the femoral and popliteal artery bypass surgery.

  5) Patients who are known to be allergic or sensitive to contrast agents, heparin, aspirin (ASA), other anticoagulant or antiplatelet therapies, and/or paclitaxel.

  6) Patients with bleeding constitution. 7) Pregnant and lactating women. 8) Patients with a history of myocardial infarction or unstable angina within 3 months.

  9) Patients with a history of TIA or cerebral infarction within 3 months. 10) Patients with severe disease such as liver failure. 11) Patients with a life expectancy of less than 24 months. 12) Participating in other drug or device studies currently. 13) Patients with poor treatment compliance or deemed unsuitable for inclusion in the group by the researcher.

Arteriosclerosis obliterans of lower extremities