With the improvement of people’s living standard and the progress of population aging, the incidence of arteriosclerosis obstruction (ASO) of the lower extremities in China has been increasing year by year, with the incidence of ASO of the lower extremities in the general population ranging from 3% to 10% and up to 15% to 20% in people over 75 years of age. Although the TransAtlantic InterSociety Consensus in 2007 recommended that bypass grafting is preferred for long-segment stenosis and occlusive lesions of the main iliac and femoral N arteries. However, with the gradual maturation of vascular surgery interventional techniques, especially the rapid development of new interventional materials, some scholars have attempted to successfully treat long-segment occlusive lesions of lower extremity arteries using percutaneoustrans luminal angioplasty (PTA ). However, due to the extensive occlusion of such lesions, severe arterial calcification, complex nature of occlusion and other characteristics, there is still a high incidence of clinical complications of endoluminal treatment, comprehensive experience of our department is summarized below, for the reference of clinicians and patients only: 1. Arterial entrapment after PTA Arterial entrapment is a more common complication after PTA treatment of long-segment arterial occlusion, balloon confined tearing of the intima and mesima during PTA This is the main cause of arterial entrapment after PTA. The following methods can be adopted to reduce the occurrence of arterial entrapment: ① choose a long balloon with a length comparable to the lesion to be dilated and shaped at one time, and avoid repeated dilatation and shaping of multiple segments as much as possible; ② use the “secondary PTA method” for severely stenosed and occluded arteries, i.e., first fill the balloon with low pressure (2-4 atm), maintain the pressure for 10-30s, and then perform the PTA with the balloon. After observing the gradual expansion of the balloon “girdle” in the lesion under fluoroscopy, the pressure should be increased to 8-10 atm, avoiding rapid expansion of the lesioned artery with violence. Separation. Stents should be used to fix the endothelium for any arterial entrapment that affects more than 30% of blood flow after PTA. For suspected arterial entrapment, multi-angle pressure pump imaging can be used for clarification. 2, arterial embolism Long segment occlusion of the superficial femoral artery often involves the opening of the superficial femoral artery, and balloon extrusion of plaque or old thrombus at the opening of the superficial femoral artery during PTA displaces proximally, which easily causes embolism of the deep femoral artery. The key to prevention is clear path guidance and accurate balloon positioning. For this complication, a 0.018″ guidewire can be used to perform PTA through the embolized deep femoral artery, and the balloon diameter should be slightly smaller than the normal deep femoral artery opening. The balloon diameter should be slightly smaller than the normal diameter of the open segment of the deep femoral artery, and the purpose is only to open the blood flow of the deep femoral artery, and the large diameter balloon should not be repeatedly dilated to avoid more serious consequences such as occlusion of the superficial femoral artery. For distal arterial embolism, the embolized segment of the artery can also be opened by PTA. 3. Arterial perforation Possible causes are summarized as follows: ① Be familiar with the anatomical course of the femoral N artery and try to advance the guidewire and catheter under the guidance of the path (road map). In some patients with long-segment artery occlusion, the pathology is actually severe stenosis or short-segment occlusion combined with thrombosis, and there are small pathways in the mechanized thrombus like a labyrinth, which can be successfully passed by using the slim and soft head end of V-18 guidewire. For some severely calcified occluded segment lesions (mostly superficial femoral artery collecting duct segments), balloon predilation or local SIA can be used to pass through. In general, arterial perforations due to guidewires do not require special treatment, but those with larger perforations (usually with existing balloon mis-dilatation) should be actively treated with moderate pressure bandaging, delayed balloon block, spring-ring embolization or even stent repair with membrane at the limb site. 4. Puncture site hematoma and pseudoaneurysm Puncture site hematoma is mostly found in the inguinal region, which should be re-pressurized and bandaged immediately after detection, and pseudoaneurysm should be ruled out by review of ultrasound. Pseudoaneurysm at the puncture site mainly presents with signs such as swelling at the puncture site, subcutaneous petechial hematoma, pulsating masses, and some combined pressure pain. After the ultrasound diagnosis is clear, the fistula can be pressed under the guidance of ultrasound probe for 20 min and wrapped with “x” shaped self-adhesive bandage for 24-48 h. Some patients with larger arterial breaches need to undergo pseudoaneurysm breach repair under anesthesia. The possible causes of bleeding were analyzed as follows: difficult arterial puncture and multiple punctures; high puncture of the femoral artery and incomplete hemostasis by compression; getting out of bed within 12 hours after surgery; long intraoperative heparinization time. 5, acute arterial thrombosis ischemic symptoms need to be treated with catheter thrombolysis under emergency DSA, thrombolytic drugs choose urokinase (initial dose 60,000 units/h) combined with heparin (initial dose 800 units/h), continuous thrombolysis intra-catheter drip, every 4h to detect the coagulation index, maintain Fg between 1.0 ~ 1.5g/L and APTT 1.5 ~ 2 times higher than normal, generally The duration of thrombolysis does not exceed 24 h. In summary, endoluminal therapy for chronic long-segment occlusion of lower extremity arteries is a safe and effective method, and has gradually become the treatment of choice for lower extremity arterial occlusion in our department. Skilled endoluminal technique, timely and correct management of complications and standardized postoperative follow-up are the keys to improve the success rate of treatment and maintain long-term arterial patency.