Correlation of Ultrasonographic Lesion Type Characterization With Angioplasty Outcomes in Failing Dialysis AVFs

Study Overview
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Brief Summary
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The continuous increase in the incidence of end stage renal disease and hemodialysis patients, has raised the interest of the vascular access scientific community and many researchers are currently investigating the potential mechanisms of arteriovenous fistulas (AVF) dysfunction. Roy-Chaudhury et al. were the first to suggest neointimal hyperplasia (NIH) as the main reason of AVF dysfunction and vessel negative remodeling as another important factor. First, Yamamoto et al. described 3 stenotic lesions categories of arteriovenous grafts (AVG) observed by ultrasonography: 1. vascular constriction type, 2. neointimal hyperplasia type, 3. mixed type (constriction and neointimal hyperplastic type). The main goals of this prospective observetional study are: The characterization of AVF stenotic lesions by ultrasonography The correlation of the stenotic lesion type with the outcomes of percutaneous transluminal angioplasty and the rate of reintervention.

Detailed Description
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This is a prospective, observetional study designed to investigate the correlation of stenotic lesion type characterization (1. vascular constriction type, 2. neointimal hyperplasia type, 3. mixed type eg. constriction and neointimal hyperplastic type) using Duplex ultrasound, with the outcomes of high pressure plain balloon angioplasty. In total 200 patients with failing dialysis arteriovenoyus fistula (AVF) scheduled to undergo angioplasty of stenotic lesion(s) will be included. The study's primary endpoint will be the correlation between stenotic lesion type and target lesion re-intervention due to clinical recurrence at 6 months follow up.

Official Title
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Characterization of STEnotic Lesion Type of Haemodialysis Arteriovenous Fistulae by Ultrasonography and Correlation With the Outcomes of Percutaneous Transluminal Angioplasty

Conditions
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Dialysis Access Malfunction

Intervention / Treatment
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* Diagnostic Test: Ultrasound characterization of stenotic lesion type


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patiens with failing AVF scheduled to undergo fluoroscopically-guided high-pressure balloon angioplasty Signed study concent form Exclusion Criteria: Patients undergoing dialysis via arteriovenous graft (AVG) Contraindications to angioplasty Immature AVF

Ages Eligible for Study
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Minimum Age: 18 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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Arms and Interventions

| Intervention/Treatment |
| --- |
|Diagnostic Test: Ultrasound characterization of stenotic lesion type|Target lesion type will be classified as restrictive, hyperplastic or mixed using high frequency Duplex ultrasound, before the angioplasty procedure and at 6 months follow up.|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Correlation of target lesion reintervention (TLR) due to clinical recurrence and lesion type | The correlation of the speciific lesion type classified based on the pre-procedural ultrasonographic assessment and the target lesion reintervention rate due to clinical recurrence, will be investigated | 6 months | 
| Lesion characterization | Lesion type will be classified as restrictive, hyperplastic or mixed based on the pre-procedural Duplex ultrasound assessment and the rates of each type will be recorded. | Less than 48 hours before the procedure | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Restenosis characterization post angioplasty | restenosis type will be classified as restrictive, hyperplastic or mixed based on the 6 months Duplex ultrasound assessment and the rates of each type will be recorded. | 6 months | 
| AVF survival | The overall AVF survival (secondary patency) will be recorded. | 6 months | 
| Binary restenosis rate | Binary (>50%) restenosis detected using Duplex ultrasound. | 6 months | 
| Periprocedural complication rate | Procedure related complications rate | Up to 48 hours post-procedure | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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angioplasty, autologous artriovenous fistula, dialysis, ultrasound, stenosis, stenosis type characterization