DCB for Dialysis Access Stent Graft Restenosis

Study Overview
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Brief Summary
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Recurrent stenosis in hemodialysis access graft (AVG) is difficult to treat. For recurrent stenosis in the anastomotic junction can be treated by stent graft to improve long-term patency. However, there is no data regarding treatment of stent graft restenosis in AVG. This randomized trial is designed to compare the efficacy and safety of drug-coated balloon (DCB) versus regular balloon in AVG stent graft restenosis.

Detailed Description
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Prosthetic arteriovenous hemodialysis access graft (AVG) has high incidences of venous anastomotic stenosis and access failure. A stent graft can be used in AVG with recurrent venous anastomotic stenosis to improve long-term patency rate. However, after stent graft implementation, the effective treatment for restenosis in a stent graft is still unknown. This randomized trial is designed to evaluate the efficacy and safety of drug-coated balloon versus regular balloon for in-stent restenosis in stent graft. The investigators plan to enroll 40 patients who presented with prosthetic AVG in-stent restenosis, and then to evaluate the restenosis lesions by intravascular ultrasound. Patients will be randomized into two groups of treatment: drug-coated balloon angioplasty or regular balloon angioplasty.

Official Title
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A Randomized Trial Comparing Drug-coated Balloon and Regular Balloon for Dialysis Access Stent Graft Restenosis

Conditions
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Hemodialysis Access Failure (Disorder), Stent-Graft Restenosis, Arteriovenous Graft, Drug-coated Balloon

Intervention / Treatment
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* Device: Regular balloon
* Device: DCB (paclitaxel-coated balloon)


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age of 20 to 90 years on regular hemodialysis at least 3 months Had stent graft implemented at dialysis vascular access Angiographic evidence of stenosis within the stent graft or less than 2 cm from the stent graft edge Clinical evidence of a hemodynamically significant stenosis or thrombosis Patient is able to provide written informed consent Exclusion Criteria: Elbow fracture or any disease involve the elbow joint that prohibits the flexion maneuver. Target lesion cannot be crossed by the guide wire. Known hypersensitivity to heparin or contrast medium. Bleeding diathesis. Patients participating in another clinical trial with interfering with this trial in the past three months. Untreatable bleeding diathesis. Other diseases, such as cancer, liver disease, or cardiac insufficiency, which may lead to protocol violations or markedly shorten a patient's life expectancy (less than 3 months). Patients unable or unwilling to participate this trial. Pregnancy, lactating woman, non-adult, criminals in sentence, psychiatric patients, research staffs or colleagues are prohibited.

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 90 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Regular balloon<br>Use the regular balloon to perform standard balloon angioplasty. | Device: Regular balloon<br>* Randomization: to use regular balloon to treat stent graft restenosis<br>|
| Active Comparator: DCB (paclitaxel-coated balloon)<br>Use DCB (paclitaxel-coated balloon) to perform additional balloon angioplasty. | Device: DCB (paclitaxel-coated balloon)<br>* Randomization: to use DCB (paclitaxel-coated balloon, Ranger, Boston-Scientific) to treat stent graft restenosis. The paclitaxel dose is 2 ug/mm2 delivered with the Ranger drug-coated balloon.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Late luminal loss | The late luminal loss found by IVUS on follow-up in comparison to index procedure. | 0, 1, and 3 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| minimal luminal area and diameter | Done by IVUS on follow-up in comparison to index procedure. | 0, 1, and 3 months | 
| restenosis rate | Compare with follow-up angiography. | 0, 1, and 3 months | 
| repeated intervention | defined by repeated endovascular balloon angioplasty or endovascular thrombectomy or surgical open thrombectomy. | 0, 1, and 3 months | 
| abandon of AV graft, death | stopped to use the target AVG or mortality | 0, 1, and 3 months |