Collateral Ligation in Failing Fistulas

Study Overview
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Brief Summary
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Arteriovenous fistulas (AVFs) for hemodialysis often fail to become usable due to failure to mature (FTM). The most common cause is narrowing of the artery or vein (stenosis). Another potential cause is the presence of collateral or side branch veins that steal blood flow from the main fistula channel. Some believe that occluding these veins might help maturation of those failing AVFs. To evaluate if this actually works, patients with FTM will be randomly assigned to side branch vein ligation (or not), and rates of AVF maturation of the two groups will be compared.

Detailed Description
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Arteriovenous fistulas (AVFs) for hemodialysis often fail to become usable due to failure to mature (FTM). The most common cause is stenosis of the artery or vein. Another potential cause is the presence of collateral or side branch veins that steal blood flow from the main fistula channel. The utility of ligating these veins to improve maturation of those failing AVFs is controversial. To evaluate this, 35 patients presenting for fistulograms for evaluation of AVFs with FTM, found to have side branch veins will be prospectively enrolled. After management of stenoses (if present), they will be randomly assigned to ligation of the venous side branches or not. Maturation rates for each group will be prospectively assessed. For patients assigned to the control group who have persistent failure to mature, a cross-over intervention will be performed and side branch ligation will be offered.

Official Title
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Prospective Randomized Evaluation of the Effect of Ligation of Venous Side Branches in Dialysis Arteriovenous Fistulas Presenting With Failure to Mature

Conditions
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Hemodialysis Access Failure

Intervention / Treatment
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* Procedure: Collateral vein ligation


Participation Criteria
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Eligibility Criteria
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Inclusion criteria: - Patients with upper extremity autogenous AVF presenting with FTM with evidence of collaterals on ultrasound and/or clinical exam. Exclusion criteria: Age under 18 years Pregnant women Prior endovascular or surgical procedure in the fistula after its creation (with the exception of surgical superficialization or mobilization) Clinical evidence of infection associated with the AVF Uncorrectable coagulopathy (International Normalized Radio >2.5, platelet count <50.000/μL) Absence of significant venous side branches on angiogram (defined as those that arise in the initial 10 cm, including the future cannulation zone, and have maximal diameter greater than or equal to one third of the widest diameter of the fistula's main venous channel in this segment).

Ages Eligible for Study
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Minimum Age: 18 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: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Collateral vein ligation<br>Ligation of collateral veins under sonographic guidance | Procedure: Collateral vein ligation<br>* Collateral venous flow will be interrupted by ultrasound-guided ligation of venous side branches.<br>|
| No Intervention: Control<br>No collateral vein ligation. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Fistula maturation rate | Proportion of patients with usable arteriovenous fistula at the end of the study (being able to deliver the prescribed dialysis dose 75% of the sessions in the first 4 weeks of use via 2 needles) | 8 weeks after randomization | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Hemodialysis fistula, Failure to mature, Collateral vein