title: Treatment of instent restenosis following stent-supported renal artery angioplasty.
abstract: OBJECTIVE
  We prospectively studied the long-term outcome of endovascular treatment of instent renal artery stenosis (IRAS).
  
  
  BACKGROUND
  Restenosis is a considerable drawback of stent-supported angioplasty of renal artery stenosis especially in small vessel diameters. The appropriate treatment strategy is not yet defined.
  
  
  METHODS
  During a 10-year period 56 consecutive patients (65 lesions) with their first IRAS were included in a prospective follow-up program (mean follow-up 53 +/- 25 months, range 6-102). Primary endpoint of the study was the reoccurence of IRAS (>or= 70%) after primarily successful treatment of the first IRAS determined by duplex ultrasound.
  
  
  RESULTS
  Primary success rate was 100%, no major complication occurred. Nineteen lesions were treated with plain balloon angioplasty (group 1, 30%), 42 lesions with stent-in-stent placement (group 2, 65%) using various bare metal balloon expandable stents, and 4 lesions with drug-eluting stent angioplasty (group 3, 6%). During follow-up, overall 21 lesions (32%) developed reoccurence of IRAS: n = 7/19 in group 1 (37%), n = 14/42 in group 2 (33%), and n = 0/4 in group 3 (0%; P = 0.573). Reoccurence of IRAS was more likely to occur in smaller vessel diameters than in larger ones [3-4mm: 4/7 (57%); 5 mm: 11/26 (42%); 6 mm: 5/25 (20%); 7 mm: 1/7 (14%), P = 0.088]. Multivariable analysis found bilateral IRAS and IRAS of both renal arteries of the same side in case of multiple ipsilateral renal arteries as independent predictors for reoccurence of IRAS.
  
  
  CONCLUSIONS
  Treatment of IRAS is feasible and safe. The data demonstrate a nonsignificant trend towards lower restenosis with restenting of IRAS versus balloon angioplasty of IRAS. Individual factors influence the likelihood of reoccurence of IRAS.
authors.affiliation: Department of Angiology, Herz-Zentrum Bad Krozingen, Bad Krozingen, Germany. Thomas.Zeller@herzzentrum.de
authors.forename: Thomas
authors.initials: T
authors.lastname: Zeller
authors.forename: Aljoscha
authors.initials: A
authors.lastname: Rastan
authors.forename: Uwe
authors.initials: U
authors.lastname: Schwarzwälder
authors.forename: Christian
authors.initials: C
authors.lastname: Mueller
authors.forename: Thomas
authors.initials: T
authors.lastname: Schwarz
authors.forename: Ulrich
authors.initials: U
authors.lastname: Frank
authors.forename: Karlheinz
authors.initials: K
authors.lastname: Bürgelin
authors.forename: Sebastian
authors.initials: S
authors.lastname: Sixt
authors.forename: Elias
authors.initials: E
authors.lastname: Noory
authors.forename: Ulrich
authors.initials: U
authors.lastname: Beschorner
authors.forename: Kirsten
authors.initials: K
authors.lastname: Hauswald
authors.forename: Daniela
authors.initials: D
authors.lastname: Branzan
authors.forename: Franz-Josef
authors.initials: FJ
authors.lastname: Neumann
mesh_terms: D000368:Aged; D017130:Angioplasty / Q000009:adverse effects / Q000379:methods*; D019917:Blood Vessel Prosthesis Implantation / Q000009:adverse effects / Q000295:instrumentation*; D005260:Female; D005500:Follow-Up Studies; D006083:Graft Occlusion, Vascular / Q000000981:diagnostic imaging / Q000601:surgery*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011859:Radiography; D012078:Renal Artery Obstruction / Q000000981:diagnostic imaging / Q000601:surgery*; D015607:Stents; D013997:Time Factors; D016896:Treatment Outcome; D014463:Ultrasonography