title: Ultrahigh-pressure versus high-pressure angioplasty for treatment of venous anastomotic stenosis in hemodialysis grafts: is there a difference in patency?
abstract: OBJECTIVE
  Ultrahigh-pressure (UHP) balloon catheters were compared with high-pressure (HP) balloon catheters to determine if there was a difference in patency after percutaneous transluminal angioplasty (PTA) of venous anastomotic stenoses.
  
  
  METHODS
  A retrospective study was conducted from January 2001 to September 2005 that included 22 patients with synthetic hemodialysis grafts who underwent 110 PTA procedures for venous anastomotic stenoses. Data collected included graft configuration and location, percent stenosis, balloon type used, residual stenosis, and total access blood flow before and after intervention. Patency from time of initial PTA to the next intervention was estimated with the Kaplan-Meier technique, with initial failures included in the analysis.
  
  
  RESULTS
  A total of 55 PTAs were performed in each group. Technical success rate was 96% (n = 106) and clinical success rate was 100%. Median survival times were 4.6 months for the UHP cohort and 5.4 months for the HP group. When each event was considered independent, the difference was significant (P = .014). However, when each PTA event was considered dependent on earlier PTA events, no significant difference in patency was observed (P = .64). The mean increases in access blood flow rate by ultrasound dilution (available for 71 events) after PTA were 264 mL/min with UHP and 524 mL/min with HP (P = .14, Student t test). One minor complication (0.9%) of focal extravasation after PTA occurred and resolved with prolonged balloon inflation.
  
  
  CONCLUSIONS
  Routine use of UHP for PTA of venous anastomotic stenoses in synthetic hemodialysis grafts was not associated with any significant change in patency compared with routine HP balloon angioplasty.
authors.affiliation: Division of Vascular and Interventional Radiology, Department of Medical Imaging, Toronto General Hospital, University Health Network-University of Toronto, 585 University Avenue, NCSB 1C-553, Toronto, Ontario M5G 2N2, Canada. dheeraj.rajan@uhn.on.ca
authors.forename: Dheeraj K
authors.initials: DK
authors.lastname: Rajan
authors.forename: Tal
authors.initials: T
authors.lastname: Platzker
authors.forename: Charmaine E
authors.initials: CE
authors.lastname: Lok
authors.forename: J Robert
authors.initials: JR
authors.lastname: Beecroft
authors.forename: Kong T
authors.initials: KT
authors.lastname: Tan
authors.forename: Kenneth W
authors.initials: KW
authors.lastname: Sniderman
authors.forename: Martin E
authors.initials: ME
authors.lastname: Simons
mesh_terms: D000328:Adult; D000368:Aged; D000800:Angioplasty, Balloon / Q000379:methods*; D001166:Arteriovenous Shunt, Surgical; D019917:Blood Vessel Prosthesis Implantation; D005260:Female; D005500:Follow-Up Studies; D006083:Graft Occlusion, Vascular / Q000503:physiopathology / Q000628:therapy*; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D011312:Pressure; D012039:Regional Blood Flow; D006435:Renal Dialysis / Q000379:methods*; D012189:Retrospective Studies; D013997:Time Factors; D016896:Treatment Outcome; D014654:Vascular Patency