Debulking Atherectomy Versus Stent Angioplasty for Limb Ischaemia of Diabetic Lower Limb Atherosclerosis-occlusive Disease.

Inclusion Criteria: 1. Age 40-80 years old 2. Rutherford grade 2 to 5 3. Patients clinically diagnosed with arteriosclerosis obliterans of lower extremity (stenosis of lower extremity arteries greater than 70% or occlusion) and complicated with diabetes 4. The target vessel diameter ≥4mm 5. The total target length of the lesion is 30-210mm 6. The subject is able and willing to comply with all requirements, including 12-month follow-up and evaluation, voluntary participation and informed consen 7. Patients with ipsilateral iliac artery inflow tract patency (stenosis ≤50%) or ipsilateral iliac artery inflow tract lesions and successful management (residual stenosis \< 30% after treatment, no severe (≥ grade D) flow-limiting dissection , no thrombosis, embolism or other serious adverse events) 8. Patients with at least one infrapopliteal artery for patency of the affected lateral foot before or after intraoperative treatment (stenosis ≤50%) Exclusion Criteria: 1. Patients with vasculitis or Berger disease 2. Patients with contraindications to antiplatelet, anticoagulant and thrombolytic drugs 3. Patients who are allergic to contrast agents and nickel titanium materials 4. Patients with severe coagulation dysfunction or severe infection that is not under control and should not undergo surgery 5. Severe renal dysfunction (creatinine \> 221umol/L) 6. Patients who received local or systemic thrombolytic therapy within 48 hours before surgery 7. Patients who had acute myocardial infarction within 30 days before surgery 8. Patients who had undergone major surgical procedures (heart, abdominal, or peripheral vascular open surgery) within 30 days before surgery 9. Patients who had a stroke within 6 months before surgery 10. Patients whose target arteries had received endovascular surgery within 14 days prior to surgery and patients who had other elective surgery plans during the study period 11. Patients with end-stage renal disease 12. Patients with previous major amputation of the target limb or restenosis after stent or bypass surgery for the target lesion 13. Patients with perforation, dissection, or other vascular injury requiring stenting or surgical operation in the approach or target vessel prior to enrollment 14. Patients with a life expectancy of \< 12 months 15. A woman who is pregnant or breastfeeding 16. Patients who are participating in clinical trials of other drugs or devices that do not meet trial endpoints 17. Patients considered unsuitable for this trial by the investigators Exclusion criteria for angiography 18. Patients with severe calcification of the target lesions 19. Patients with aneurysms in the target vessels 20. Patients with acute or subacute thrombus in the target vessel 21. Patients with artificial vessels placed in the limb on the same side of the target vessel