• Rutherford grade 4-5.

• Patients who understand the purpose of this study, volunteer to participate in the experiment, sign informed consent and are willing to follow up.

• Single or sequential de novo or restenotic lesions (stenosis ≥ 70% diameter reduction or occlusion) in the infrapopliteal arteries \>20 mm. Lesions should not extend beyond the ankle joint.

• Successful wire crossing of the lesion. After the pre-dilation of the ordinary balloon, the angiography showed that there was continuous blood flow.

• At least one of the infrapopliteal arteries received a drug-coated balloon.

• For patients with aortoiliac artery disease and femoral-popliteal artery disease, after intravascular reconstruction, blood flow can be recanalized, and there is no residual stenosis of more than 50%.

• In patients with lower extremity arterial thrombosis, after mechanical thrombectomy, percutaneous catheter thrombolysis, and thrombus removal, patients receiving blew the knee arterial drug balloon intervention.

• Patients who have received DCB intervention for both lower limbs can be enrolled in the group according to the intracavitary treatment time.

• Life expectancy\> 24 months.