I. Clinical data of 11 patients with lower limb arterial thrombosis. Among them, 9 cases were male and 2 cases were female, aged from 33 to 69 years old, with an average age of 53 years old. All of them were admitted to the hospital because of sudden onset of severe pain in the lower limbs with numbness, coldness, and pale or black skin. Examination: the arterial pulsation of the distal lower limbs was significantly weakened or disappeared. The shortest medical history was 3 hours and the longest was 20 days. The embolization sites were abdominal aorta in 1 case, iliac artery in 2 cases, femoral artery in 6 cases, N artery in 1 case, and extensive thrombosis of femoral artery, N artery, anterior posterior tibial artery and foot artery in 1 case. All of them used a combination of ATD mechanical thrombus removal and urokinase pharmacological thrombolysis to deal with arterial thrombosis in each part of the group. Second, the ATD dipping soft thrombolysis method After connecting the ATD catheter to the nitrogen drive device, the ATD catheter was delivered to the proximal 1-2 cm of the thrombus via the catheter sheath, and the built-in blade of the catheter head was immediately rotated at a speed of 100,000-200,000 rpm by stepping on the foot gate of the nitrogen drive device, while the catheter was slowly advanced to cut the thrombus into particles of <15 μm size and enter the blood circulation. When used, the ATD catheter is sent to the proximal end of the thrombus, and the nitrogen drive device is activated to move the catheter back and forth at a speed of 0.5 cm per second under fluoroscopy, and this is repeated 3-4 times to clear the thrombus before pushing the contrast agent to observe the efficacy until the thrombus is completely removed. In one case of common iliac artery thrombosis, the thrombus was broken by repeated rotation with a pigtail catheter or pulled to the femoral artery with a balloon catheter and then mechanically removed with an ATD catheter. 10 cases of femoral N artery (or external iliac artery) thrombosis were directly thrombolized with an ATD dip. Third, urokinase pharmacological thrombolysis was performed for the thrombus in the small artery distal to the knee after softening thrombolysis with an ATD catheter. If the thrombus is widely distributed or the intraoperative thrombolysis is not complete, the catheter is left in the ward for continuous thrombolysis with 500,000 to 1,000,000 units/day and maintained with a micro pump for 3 to 5 days. For intraoperative vasospasm, 10-60 mg of poppy bases were instilled via catheter to relieve spasm, and lidocaine was instilled to relieve pain caused by ischemia or contrast stimulation in the lower limbs. After the operation, subcutaneous injection of rapid coagulation avoidance 0.4 ml, 2 times/day, and after 3 days, change to oral warfarin 2.5 mg/time, 1 time/day, for 3-6 months. Fourth, balloon dilatation or stenting was performed using the Seldinger technique [3] to perform arteriography and pressure measurement of the affected limb through the contralateral or ipsilateral femoral artery puncture and cannulation, and to clarify the site, extent and degree of arterial stenosis, and then perform balloon dilatation and stenting (Percutaneous Transluminal Angioplasty (PTA) or placement of stents in the stenotic segment. As a result, the technical implementation success rate was 100% in 11 cases, the clinical performance improvement rate was 100%, the revascularization rate was 90.9%, and the quality of life was significantly improved. In 8 cases, the arterial pulsation of the affected limb was restored, the numbness and pain of the limb disappeared, the skin temperature and color returned to normal, and the blood pressure measurement showed the same as that of the healthy side; in 3 cases, the postoperative indwelling catheter continued thrombolysis for 3 to 5 days to achieve recanalization, and the function of the affected limb was restored, the skin temperature was normal, but the arterial pulsation was still weakened and mildly numb. In six of the cases, the lumen was restored to normal after balloon dilation or stent placement in seven stenotic segments. All cases were followed up by DSA, ultrasound and clinical follow-up for 1 to 25 months, and the arteries remained patent. There were no complications of vascular perforation or amputation, and one case of gastrointestinal bleeding occurred during thrombolysis. Discussion When the stenosis rate of lower limb artery is less than 50%, there may be no limb ischemic symptoms, but due to the dislodgement of intracardiac thrombus or hemodynamic changes, the smoothness of the vessel wall decreases, and the increase of blood viscosity secondary to thrombosis can lead to complete occlusion of the stenotic segment, at which time the clinical symptoms suddenly increase significantly and severe ischemic manifestations appear. Emergency interventional surgery can not only clearly diagnose the site, scope and severity of arterial embolism and provide a basis for the formulation of treatment plan, but also provide simultaneous treatment, which can effectively save the limb and avoid amputation or reduce the plane of amputation. At present, the application of balloon dilation and stenting for limited stenosis of lower limb arteries is more mature. However, there are still difficulties in the treatment of massive thromboembolism in large arteries and subacute chronic thrombosis.ATD dip soft thrombolysis thrombolysis is performed by pneumatic rotary cutting system to make the blade at the head end of the catheter rotate at a speed of 100-200,000 rpm to cut the thrombus into <15µm particles into the blood circulation without blood loss. It is effective in thrombosis up to 2 weeks and dispels clots rapidly. However, the ATD catheter is not guided by a microguide, and should be driven as slowly as possible from the proximal end to the distal end or retracted from the distal end to the proximal end to avoid penetrating the vessel, and the possibility of hemolysis due to destruction of red blood cells by mechanical thrombolysis should also be taken into account; therefore, the cumulative use time should not exceed 10 min. for arteries with a diameter of 4-6 mm or for acute phase thrombosis within 3 days, OASIS can also be used. The ATD catheter and the OASIS catheter work differently and have different clinical applications (see Table 1). both have in common the lack of fracture resistance due to stiffness and the inability to cross the abdominal aorta to reach the contralateral iliac artery, so the affected side should be selected for paracentesis cannulation and placement of the 7Fr catheter sheath. It should not be used for the distal knee vessels because the lumen is too small; otherwise, it is prone to vessel rupture. If the thrombus is confined to the proximal knee, it can be completely recanalized within a few minutes intraoperatively by mechanical removal of the thrombus, but for embolism longer than 2W or simultaneous thrombosis of the distal knee artery, a catheter should be left in place for continuous thrombolytic therapy after surgery. In one case of nephrotic syndrome in this group, the blood was in a hypercoagulable state, with extensive thrombosis in both lower extremity arteries, and the disease progressed rapidly before surgery, and the skin black spots extended from the foot to the thigh within 2 days, which was treated with anticoagulation and treatment of the primary disease [6], combined with continuous infusion of urokinase in both femoral arteries after soft thrombolysis with ATD catheter immersion for 5 days of complete thrombus clearance. Complications during thrombolysis should also be fully considered. Such as femoral artery pseudoaneurysm, cerebral hemorrhage, and renal hemorrhage have been reported [7]. In one case in our group, after high-dose urokinase thrombolysis of the femoral artery complicated by gastrointestinal bleeding, drug thrombolysis was immediately stopped and replaced by soft thrombolysis with an ATD catheter with simultaneous hemostatic treatment, which achieved both no bleeding and complete thrombus clearance [8]. In another case of abdominal aortic embolism caused by dislodged thrombus in rheumatic heart disease, the thrombus was completely cleared at that time after mechanical removal of thrombus by ATD combined with urokinase drug thrombolysis, but on the third day the intracardiac thrombus dislodged again and caused sudden death due to large cerebral infarction, which may be related to the use of anticoagulants and urokinase to promote the dislodgement of intracardiac thrombus, for the treatment of intracardiac thrombus there is no simple method, but before arterial thrombolysis routine There is no simple method for the treatment of intracardiac thrombus, but before thrombolysis of artery, cardiac ultrasound should be performed routinely, and if there is still a thrombus in the heart, mechanical removal of thrombus should be chosen to avoid serious consequences caused by drugs.