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).

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.

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.

Consecutive patients undergoing fluoroscopically-guided percutaneous balloon angioplasty due to dysfunctional AVF and assessed with pre-and post-procedural volume flow measurements using percutaneous DUS

Available after study publication, upon reasonable request

Starting 1 month after publication and for 2 years

Reasonable request (systematic review, metaanalysis)