Volume Flow Assessment to Optimize Angioplasty of Dysfunctional Dialysis Access

Study Overview
=================
Brief Summary
-----------------
This is a multicenter, prospective study investigating a new concept of intra-procedural percutaneous duplex ultrasound (DUS) volume flow-guided balloon angioplasty for the quantification and optimization of endovascular treatment outcomes of dysfunctional autologous arteriovenous fistulae (AVF).

Detailed Description
-----------------
This is a prospective, multi-center, single-arm observational clinical trial investigating a new functional index of success of endovascular treatment of dysfunctional AVF assessed with intraprocedural percutaneous DUS. The study will include 100 consecutive patients undergoing fluoroscopically-guided percutaneous balloon angioplasty due to dysfunctional AVF. Exclusion criteria will be (i) patients with arteriovenous synthetic grafts. (ii) Immature AFVs not previously used for hemodialysis (at least once). Patients' demographical data, dialysis access history, and procedural details will be recorded. Intraprocedural volume flow measurements will be obtained just prior to the procedure and after final balloon dilation, before sheath removal. Clinical follow-up will be set at 6 months after the index procedure. All DUS measurements will be performed using the same imaging protocol. The study's primary endpoints will be (i) the quantification of angioplasty outcome using DUS volume flow analysis before sheath insertion and at the end of the procedure before sheath removal and (ii) to assess the correlation between volume flow at the end of the procedure and clinically driven re-intervention-free rate at defined as the rate of reintervention due to dysfunction recurrence of the treated AVF. Secondary endpoints will be (i) to assess the correlation between volume flow and clinical success defined as high-quality dialysis for a period of at least one month and (ii) identification of independent predictors of re-intervention-free rate.

Official Title
-----------------
Volume Flow Assessment to Optimize Angioplasty of Dysfunctional Dialysis Access. The VOLA II Multicenter Study

Conditions
-----------------
Dialysis Access Malfunction

Intervention / Treatment
-----------------
* Diagnostic Test: Percutaneous DUS volume flow measurements


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Consecutive patients undergoing fluoroscopically-guided percutaneous balloon angioplasty due to dysfunctional AVF Signed consent form Agree to the study protocol Exclusion Criteria: Patients with arteriovenous synthetic grafts Patients with contraindication to antiplatelet therapy Immature AFVs, not previously used for at least one dialysis session.

Ages Eligible for Study
-----------------
Minimum Age: 18 Years
Maximum Age: 90 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Volume flow group<br>The study will include consecutive patients undergoing standard fluoroscopically-guided percutaneous balloon angioplasty due to dysfunctional AVF. Intraprocedural volume flow measurements will be obtained just prior to the procedure and after final balloon dilation. | Diagnostic Test: Percutaneous DUS volume flow measurements<br>* Volume flow measurements of the AFV will be obtained using intraprocedural DUS just prior to sheath insertion and at the end of the final balloon dilation, before sheath removal.<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Quantification of angioplasty outcome | The quantification of angioplasty outcomes will be performed using DUS volume flow analysis | At the end of the procedure | 
| Correlation between volume flow and clinically-driven reintervention rate | The investigators will use ROC analysis to define cut off values of volume flow at the end of the procedure to predict clinically-driven reintervention rate | 6 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Re-intervention-free rate | The clinically driven re-intervention-free rate due to dysfunction recurrence of the treated AVF following endovascular treatment | 6 months | 
| Identification of independent predictors of reintervention | Multivariable analysis will be performed to identify independent predictors of reintervention-free rate | 6 months | 
| Procedure related complications | Minor and major procedure related complications will be recorded | 1 week | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
Percutaneous transluminal angioplasty, Volume-flow measurement, Autologous arteriovenous fistula, Dialysis access, Interventional Radiology