title: Short-term outcomes of borderline stenoses in vascular accesses with PTFE grafts.
abstract: BACKGROUND
  There are controversial data about vascular access stenosis surveillance by ultrasonography. The definition of stenosis significance varies among centres. We performed a retrospective study to describe short-term outcomes of borderline asymptomatic stenoses defined by precise criteria and to determine possible risk factors of stenosis progression.
  
  
  METHODS
  We studied the outcome of borderline stenoses in accesses with PTFE grafts. Stenosis was considered significant if there was a combination of >50% lumen reduction and peak systolic ratio >2, together with at least one of the following additional criteria: (1) residual diameter <2.0 mm and (2) flow reduction of >25% or actual flow volume <600 ml/min. Stenosis was considered borderline in the absence of the additional criteria.
  
  
  RESULTS
  Of the 102 borderline stenoses, after 11 +/- 6 weeks, 55 remained non-progressive, in 38 the degree of the stenosis progressed, in 8 a percutaneous transluminal angioplasty (PTA) was performed due to clinical indication and only 1 thrombosed. A significant relative risk of developing significant stenosis was found in grafts with prior PTA [RR = 1.91 (95% CI: 1.27, 2.88), P = 0.002] and in female gender [RR = 2.29, (95% CI: 1.29, 4.06), P = 0.025].
  
  
  CONCLUSIONS
  Delaying PTA of borderline stenoses is safe using this watch-and-wait strategy and stenoses remain stable over at least short time, but with higher risk of progression especially after prior PTA. We believe that the definition of precise criteria of stenosis significance is necessary for the benefit of ultrasound surveillance.
authors.affiliation: Third Department of Internal Medicine, General University Hospital, First Faculty of Medicine, Charles University in Prague, Czech Republic. Vladimir.Tuka@vfn.cz
authors.forename: Vladimir
authors.initials: V
authors.lastname: Tuka
authors.forename: Marcela
authors.initials: M
authors.lastname: Slavikova
authors.forename: Zdislava
authors.initials: Z
authors.lastname: Krupickova
authors.forename: Magdalena
authors.initials: M
authors.lastname: Mokrejsova
authors.forename: Eva
authors.initials: E
authors.lastname: Chytilova
authors.forename: Jan
authors.initials: J
authors.lastname: Malik
mesh_terms: D000800:Angioplasty, Balloon; D001807:Blood Vessel Prosthesis / Q000009:adverse effects*; D002408:Catheters, Indwelling / Q000009:adverse effects*; D003251:Constriction, Pathologic / Q000209:etiology / Q000628:therapy; D018450:Disease Progression; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011138:Polytetrafluoroethylene; D006435:Renal Dialysis; D012189:Retrospective Studies; D013997:Time Factors; D016896:Treatment Outcome; D014652:Vascular Diseases / Q000209:etiology* / Q000628:therapy*
chemical_list: D011138:Polytetrafluoroethylene