The purpose of this clinical trial is to compare the efficacy and safety of cutting balloons versus drug-coated balloons in treating venous stenosis of autologous arteriovenous fistulas.The main questions it aims to answer are:

1. Will drug-coated balloons achieve a better CD-TLR rate compared to cutting balloons?
2. What medical problems do participants have when receiving treatment with drug-coated balloons or cutting balloons?

The study will recruit 180 patients with venous segment stenosis of autologous arteriovenous fistulas at multiple centers from June 2024 to December 2025. Patients will be divided into two cohorts based on the treatment method: the Cutting Balloon group and the Drug-Coated Balloon group. The primary outcomes observed will be the primary patency rates of the target lesion at 1, 3, 6, and 12 months post-operation, re-intervention rates of the target vessel, and the technical success rates and procedural success rates of the two devices, along with major adverse events during the perioperative period.

Inclusion Criteria:

Subjects aged between 18 and 75 years. Subjects possess a mature upper limb autologous arteriovenous fistula (AVF) and have undergone at least one hemodialysis session.

Target lesion must be located in the venous segment of the upper limb AVF. Doppler ultrasound confirms that the target lesion stenosis is ≥50%, accompanied by at least one of the following clinical manifestations: elevated venous pressure during dialysis, abnormal fistula signs, significant reduction in blood flow (<200ml/min).

Guidewire and balloon successfully pass through the lesion and complete dilation. 6.Subjects or their legal representatives must understand the purpose of the trial, voluntarily participate in the clinical trial, and sign an informed consent form, while also being willing to adhere to the specific follow-up schedules set by this trial.

Exclusion Criteria:

Target lesion located in the arterial segment or anastomosis of the AVF. Target lesion located in the lower limb AVF. Subjects with previous stent implantation in the AVF. Patients diagnosed with symptomatic central venous occlusive disease: AVF flow reduction accompanied by swelling of the ipsilateral limb, chest, or facial area, with DSA confirmation of central venous occlusive disease.

Subjects with two or more target lesions in the AVF (when two stenoses are less than 3 cm apart, they are considered as one target lesion).

Subjects with acute thrombosis in the AVF or who have undergone AVF thrombolysis or thrombectomy within the past 30 days.

Subjects who have undergone or plan to undergo surgical intervention on the AVF within 30 days.

Subjects with AVF infection or concurrent systemic active infection. Subjects planning renal transplantation or switching to peritoneal dialysis within the next 12 months.

Subjects with diseases causing coagulopathy, such as thrombocytopenic purpura. Subjects undergoing immunotherapy or suspected/diagnosed with vasculitis. Subjects with allergies or contraindications to heparin or contrast agents. Subjects who are pregnant or breastfeeding. Subjects with a life expectancy of less than 12 months.

Dysfunctional autogenous arteriovenous fistula patient: A stenosis in a hemodialysis access with significant hemodynamic changes: Based on angiography/ultrasound evaluation, the target lesion stenosis is ≥50%, and is accompanied by one or more of the following clinical and physiological abnormalities: natural fistula blood flow <480ml/min; unable to meet the required blood flow for the dialysis prescription; thrombosis in the autogenous arteriovenous fistula; elevated venous pressure during dialysis; difficult cannulation; decreased dialysis adequacy; and abnormal signs in the fistula, etc.