title: Patient-specific computational modeling of upper extremity arteriovenous fistula creation: its feasibility to support clinical decision-making.
abstract: BACKGROUND
  Inadequate flow enhancement on the one hand, and excessive flow enhancement on the other hand, remain frequent complications of arteriovenous fistula (AVF) creation, and hamper hemodialysis therapy in patients with end-stage renal disease. In an effort to reduce these, a patient-specific computational model, capable of predicting postoperative flow, has been developed. The purpose of this study was to determine the accuracy of the patient-specific model and to investigate its feasibility to support decision-making in AVF surgery.
  
  
  METHODS
  Patient-specific pulse wave propagation models were created for 25 patients awaiting AVF creation. Model input parameters were obtained from clinical measurements and literature. For every patient, a radiocephalic AVF, a brachiocephalic AVF, and a brachiobasilic AVF configuration were simulated and analyzed for their postoperative flow. The most distal configuration with a predicted flow between 400 and 1500 ml/min was considered the preferred location for AVF surgery. The suggestion of the model was compared to the choice of an experienced vascular surgeon. Furthermore, predicted flows were compared to measured postoperative flows.
  
  
  RESULTS
  Taken into account the confidence interval (25(th) and 75(th) percentile interval), overlap between predicted and measured postoperative flows was observed in 70% of the patients. Differentiation between upper and lower arm configuration was similar in 76% of the patients, whereas discrimination between two upper arm AVF configurations was more difficult. In 3 patients the surgeon created an upper arm AVF, while model based predictions allowed for lower arm AVF creation, thereby preserving proximal vessels. In one patient early thrombosis in a radiocephalic AVF was observed which might have been indicated by the low predicted postoperative flow.
  
  
  CONCLUSIONS
  Postoperative flow can be predicted relatively accurately for multiple AVF configurations by using computational modeling. This model may therefore be considered a valuable additional tool in the preoperative work-up of patients awaiting AVF creation.
authors.affiliation: Department of Surgery, Maastricht University Medical Center, Maastricht, The Netherlands. aronbode@gmail.com
authors.forename: Aron S
authors.initials: AS
authors.lastname: Bode
authors.forename: Wouter
authors.initials: W
authors.lastname: Huberts
authors.forename: E Marielle H
authors.initials: EM
authors.lastname: Bosboom
authors.forename: Wilco
authors.initials: W
authors.lastname: Kroon
authors.forename: Wim P M
authors.initials: WP
authors.lastname: van der Linden
authors.forename: R Nils
authors.initials: RN
authors.lastname: Planken
authors.forename: Frans N
authors.initials: FN
authors.lastname: van de Vosse
authors.forename: Jan H M
authors.initials: JH
authors.lastname: Tordoir
mesh_terms: D001166:Arteriovenous Shunt, Surgical; D001775:Blood Circulation; D019295:Computational Biology; D003657:Decision Making; D005240:Feasibility Studies; D006801:Humans; D011184:Postoperative Period; D057234:Preoperative Period; D011446:Prospective Studies; D034941:Upper Extremity / Q000098:blood supply*; D014654:Vascular Patency