The Effectiveness of FRAME FR for AVF Repair in High-Flow Reduction & Stabilization, A Prospective Trial

The Effectiveness of FRAME FR for ArterioVenous Fistula Repair in High-Flow Reduction, A Prospective, Monocenter Controlled Trial

Patients with end-stage renal disease require permanent vascular access to enable safe and effective hemodialysis. An arteriovenous fistula (AVF), where a vein is mobilized and connected to an artery in the arm, is considered the gold standard and first choice for vascular access. After fistula creation, the vein is subjected to high pressure and flow, and undergoes remodeling. This includes the possibility of significant dilatation and intimal hyperplasia. Normal AVF flow required for effective dialysis is around 0.6 liters/min or 0.4-0.8 liters/min. However, in at least 20% of patients, excessive remodeling and dilatation of the fistula result in a high flow AVF with >2 liters/min.

High flow fistulas significantly increase the risk for the development of high output cardiac failure, skin breakdown, bleeding, hand ischemia, and other systemic complications. In cases of high flow AVF, venous reconstruction procedures, banding and/or plication, are often required to limit venous diameter and flow. The longevity of this procedure is limited as the reconstructed segment remodels and re-dilates due to ongoing arterial pressure. Banding and plication are both procedures that are designed to increase resistance to flow. Banding is performed by wrapping a segment of polytetrafluoroethylene (PTFE) around the outflow tract of the fistula, or by placing a suture around the fistula near the arterial anastomotic area to create a narrowing. Fistula plication involves narrowing of a short segment of the proximal venous outflow tract, usually accomplished by suturing or stapling the fistula for 2-6 cm. One of the notable systemic effects of a hemodialysis AVF is an acute decrease in systemic vascular resistance with a simultaneous increase in venous return to the heart, and thus an increase of the cardiac output. Cardiac failure occurs more frequently in patients with an access flow QA>2 l/min and CPR≥20%. Another adverse systemic effect of AV fistulas is pulmonary hypertension. The increased flow volume to the heart from an AV fistula yields an increase in pulmonary pressures. This can limit pulmonary vasodilation and result in pulmonary hypertension.

Inclusion Criteria:

• Patient aged over 18 years
• Patient with a fistula flow >1.5l/min
• Patient with a hemodialysis AVF and heart failure symptoms and who may require a reduction in flow even if <1.5l/min
• Patient whose AVF flows <1.5l/min and who may require a flow reduction for a reduction of edema in case of central vein stenosis or symptom of steal syndrome
• Patient referred by a cardiologist for high output cardiac failure
• Patient who is able and willing to comply with the study follow up requirements
• French speaking patient
• Patient who is affiliated to a social security system
• Patient who is able and willing to give his informed written consent.

Exclusion Criteria:

• Patient with any local near fistula or systemic sign or infection
• Patient with AV Fistula composite (constructed or prosthetic graft and vein
• Patient with stents within the operative portion of the fistula
• Patients with known central venous stenosis or occlusion
• Patients with a hand ischemia
• Patient with wall thickness >2 mm, with separation or thrombus within the operative portion of the fistula that cannot be removed, as determined intraoperatively
• Hypercoagulability, on chronic anticoagulation
• Pregnant and breastfeeding women
• Concomitant life-threatening disease, likely to limit life expectancy to less than two years
• Inability to tolerate or comply with required guideline based upon post-operative drug regimen
• Inability to tolerate or comply with required follow-ups
• Concurrent participation in an interventional (drug or device) study for which the follow-up is not completed
• Patient unable or unwilling to perform all the requested tasks
• Patient under tutorship or curatorship
• Patient deprived of liberty.