title: Radiofrequency perforation system for in vivo antegrade fenestration of aortic stent-grafts.
abstract: OBJECTIVE
  To evaluate the ability to create in vivo antegrade fenestrations (IVAF) using a radiofrequency probe in juxtarenal aortic stent-grafts to preserve the patency of renal arteries.
  
  
  METHODS
  Modified stent-grafts with an unsupported fenestration area were deployed in the juxtarenal aorta of 2 25-kg dogs. Prior to deployment, both renal arteries were marked with detachable coils that were later removed (dog 1) or with hydrophilic catheters (dog 2). After deployment, a radiofrequency probe was used to perforate the graft. If puncture was successful, attempts were made to pass guidewires into the renal arteries for balloon dilation and stenting of the graft perforation. Doppler ultrasound scans of the renal arteries were taken after 1 week. Doppler ultrasound and angiography were repeated prior to autopsy and macroscopic analysis at 1 month.
  
  
  RESULTS
  Fenestration was attempted in 3 renal arteries (1 in dog 1 and 2 in dog 2). It was successful in 2 renal arteries but required 6 attempts in dog 1 and 3 in dog 2. The failed case was related to the position of a stent-graft strut close to the fenestration area. One stent thrombosis was seen during follow-up, while the other fenestrated artery remained patent. No stent fracture was encountered during follow-up.
  
  
  CONCLUSIONS
  This radiofrequency device allowed successful fenestration but was difficult to control. Technical improvements are required to improve clinical success and patency.
authors.affiliation: Division of Vascular Surgery, University Health Network Toronto General Hospital, University of Toronto, Ontario, Canada.
authors.forename: Leonard W H
authors.initials: LW
authors.lastname: Tse
authors.forename: Sophie
authors.initials: S
authors.lastname: Lerouge
authors.forename: Bao T
authors.initials: BT
authors.lastname: Bui
authors.forename: Eric
authors.initials: E
authors.lastname: Therasse
authors.forename: Hélène
authors.initials: H
authors.lastname: Héon
authors.forename: Gilles
authors.initials: G
authors.lastname: Soulez
mesh_terms: D017130:Angioplasty / Q000295:instrumentation*; D000818:Animals; D001807:Blood Vessel Prosthesis; D019917:Blood Vessel Prosthesis Implantation / Q000295:instrumentation*; D017115:Catheter Ablation / Q000295:instrumentation*; D004285:Dogs; D023421:Models, Animal; D011474:Prosthesis Design; D017755:Prosthesis Fitting / Q000295:instrumentation*; D012077:Renal Artery / Q000601:surgery*; D015607:Stents; D014654:Vascular Patency