Treatment of Arteriovenous Fistula (AVF) Stenosis
Balloon angioplasty (with high pressure as needed) is the primary first-line treatment for clinically and angiographically significant AVF stenosis, with the exception of juxta-anastomotic stenosis where surgical revision with a new AV anastomosis is preferred. 1
When to Treat AVF Stenosis
Treatment is indicated when stenosis is both clinically and angiographically significant 1:
- Anatomic criteria: >50% reduction in vessel diameter on imaging 1
- Clinical/physiologic criteria must also be present 1:
Critical pitfall: Anatomic stenosis alone without clinical symptoms is inadequate justification for intervention 1. The stenosis must be causing hemodynamic compromise.
Primary Treatment Algorithm by Stenosis Location
Juxta-Anastomotic Stenosis (First Post-Anastomotic Venous Segment)
Surgical revision is the preferred treatment 1:
- Create a new AV anastomosis using healthy venous segment located a few centimeters more proximally 1
- Surgery provides better long-term results than repeated angioplasty for this location 1
- Repeated angioplasty is more expensive with increased morbidity and risk for catheter placement 1
Stenosis Within Cannulation Areas
Percutaneous transluminal angioplasty (PTA) is first-line treatment 1:
- Standard or high-pressure balloon angioplasty (>20 atm) 1
- Technical success defined as <30% residual stenosis 1
- Clinical success requires at least one successful dialysis session post-treatment 1
- Avoid stent placement in cannulation segments 1
Stenosis in Venous Outflow Tract (Non-Cannulation Sites)
PTA is the treatment of choice 1:
- When elastic recoil occurs, combine PTA with stent-graft insertion 1
- Stent-grafts are preferred over angioplasty alone for graft-vein anastomotic stenosis (better 6-month outcomes) 1
- Avoid bare metal stents - use self-expanding stent-grafts only 1
Escalation Strategy for Resistant Stenosis
When standard balloon angioplasty fails during the procedure 2, 3:
- Upsize the balloon 2
- Prolong balloon inflation time 2
- Use ultra-high-pressure balloons (>30 atm) 2, 4
- Consider cutting or scoring balloons 2, 3
- Drug-coated balloons (DCBs) - evidence shows improved patency but FDA warning exists regarding long-term mortality in peripheral artery disease 1
Important caveat: The 2020 KDOQI guidelines state there is inadequate evidence to recommend specialized balloons (drug-coated or cutting) over standard high-pressure balloons 1. However, multiple randomized trials show DCBs improve patency rates 1.
Management of Recurrent Stenosis
Recurrence within 3-12 months 2:
- Lower threshold for using drug-coated balloons in all regions 2
- Consider stent-grafts in all regions except inflow segment 2
- Stent-grafts are preferred over angioplasty alone for in-stent restenosis (better 6-month outcomes) 1
Recurrence after 12 months 2:
Surgical revision indicated when 2-3 interventions required within 1-3 month period 1
Expected Outcomes
PTA clinical success rates 1:
- Technical success: 85-98% 1
- Primary patency at 6 months: 38-63% 1
- Primary patency at 12 months: 23-44% 1
- Secondary patency at 12 months: 81-82% 1
Critical Pitfalls to Avoid
- Delaying treatment of clinically significant stenosis leads to thrombosis and access failure 5
- Placing stents in cannulation segments compromises future access use 1
- Treating anatomic stenosis without clinical symptoms - this is inappropriate 1
- Using bare metal stents - these should be avoided entirely 1
- Ignoring juxta-anastomotic location - these require surgical revision, not repeated angioplasty 1
Individualized Approach
Treatment decisions should involve the vascular access team (nephrologist, interventionalist, surgeon, vascular access coordinator) and consider the patient's ESKD Life-Plan, operator expertise, and local capabilities 1. However, the algorithmic approach above provides the evidence-based framework for decision-making.