title: Nonmaturation of arm arteriovenous fistulas for hemodialysis access: A systematic review of risk factors and results of early treatment.
abstract: BACKGROUND
  Arteriovenous fistula (AVF) nonmaturation increases reliance of hemodialysis patients on grafts and catheters, exposing them to associated high complication risks. This systematic review assessed the success rates and complications of therapeutic interventions in arm hemodialysis AVFs experiencing nonmaturation. It also compared the efficacy of preoperative clinical factors (eg, age, gender, race), and preoperatively and postoperatively acquired hemodynamic parameters (eg, arterial diameter or blood flow through the AVF) at stratifying risk of nonmaturation.
  
  
  METHODS
  Two independent researchers used a systematic strategy to search literature databases and extract data from articles judged relevant and valid. The evidence base for this review comprised 33 articles, 12 about treatment, and 21 concerning risk stratification. A meta-analysis was performed to calculate summary measures for nonmaturation treatment success and risk stratification efficacy (eg, excess risk and relative risk) of preoperative clinical, preoperative hemodynamic, and postoperative hemodynamic risk factors.
  
  
  RESULTS
  The success rate of early endovascular or surgical treatment, defined as the possibility of achieving adequate hemodialysis, averaged 86%, with 1-year primary patencies of 51%, 1-year secondary patencies of 76%, and complication rates of 9.3%, with 5.5% minor complications. Overall, patients with preoperative clinical risk factors had excess nonmaturation risks of 21% (95% confidence interval [CI], 11%-30%) and a relative risk of 1.7 (95% CI, 1.3-2.1). Patients with preoperative hemodynamic risk factors had average estimated excess risks of 24% (95% CI, 15%-33%) and a relative risk of 1.7 (95% CI, 1.4-2.0). Patients with hemodynamic risk factors present shortly after operation had excess nonmaturation risks of 50% (95% CI, 42%-58%) and a relative risk of 4.3 (95% CI, 3.4-5.5).
  
  
  CONCLUSIONS
  Patients can be treated effectively for AVF nonmaturation early on, and it is possible to identify those patients at risk of nonmaturation most effectively with an early postoperative assessment of hemodynamic risk factors. Additional research is needed that concentrates on adopting the strategy of early treatment of patients with postoperative risk factors.
authors.affiliation: Department of Radiology, University Medical Centre Utrecht, Utrecht, The Netherlands. ehjvoormolen@gmail.com
authors.forename: Eduard H J
authors.initials: EH
authors.lastname: Voormolen
authors.forename: Abdelkarime Khodadade
authors.initials: AK
authors.lastname: Jahrome
authors.forename: Lambertus W
authors.initials: LW
authors.lastname: Bartels
authors.forename: Frans L
authors.initials: FL
authors.lastname: Moll
authors.forename: Willem P
authors.initials: WP
authors.lastname: Mali
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Blankestijn
mesh_terms: D001166:Arteriovenous Shunt, Surgical / Q000009:adverse effects*; D006083:Graft Occlusion, Vascular / Q000209:etiology* / Q000503:physiopathology / Q000601:surgery; D006439:Hemodynamics; D006801:Humans; D006435:Renal Dialysis; D012086:Reoperation; D018570:Risk Assessment; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome; D034941:Upper Extremity / Q000098:blood supply*; D014654:Vascular Patency