Factors influencing haemodialysis arteriovenous fistula patency after balloon angioplasty: a systematic review

Aim: Percutaneous transluminal angioplasty (PTA) is an established treatment for haemodialysis fistula stenosis. This study aimed to systematically review evidence for factors associated with patency after percutaneous transluminal angioplasty (PTA).\ud \ud Background: The effects of patient comorbidity, demographic, biochemical and anatomical characteristics, with initial PTA success and post-intervention patency have not previously been summarised.\ud \ud Methods: We searched databases to identify studies assessing patency after PTA in haemodialysis fistulae. Studies of immature or thrombosed fistulae or other dialysis access were excluded. Quality of studies was assessed using a modified validated checklist. Outcomes assessed were post-intervention primary and secondary patency, restenosis at 6 months, technical and clinical success, assisted primary patency and mean interval or frequency of endovascular interventions during follow up. Findings were summarized descriptively.\ud \ud Results: We included 12 single-centre studies of 1 120 participants with 1281 fistulae. Follow-up ranged from 3 days-10years. Shorter primary patency was seen with more recent fistulae (4 studies), longer stenosis length, upper arm fistulae (2 studies), small inflow artery diameter, arteriovenous anastomotic site and history of previous endovascular interventions (1 study each). Shorter secondary patency was seen with increased patient age (2 studies), and more recent fistulae (1 study). Early restenosis was associated with diabetes (3 studies), HbA1c, low-density lipoprotein, and asymmetric dimethylarginine (1 study each). Technical success was reduced for upper arm fistulae and high-grade stenoses (1 study), while clinical success of PTA was more likely in stenotic compared to thrombosed fistulae (1 study).\ud \ud Conclusion: Fistula characteristics and diabetes may be associated with poor PTA outcomes, however evidence is inconclusive, and the role of metabolic and inflammatory markers is unclear