title: Impact of geographic miss on adjacent coronary artery segments in diffuse in-stent restenosis with beta-radiation therapy: angiographic and intravascular ultrasound analysis.
abstract: BACKGROUND
  The impacts of geographic miss on edge restenosis have not been sufficiently evaluated.
  
  
  METHODS
  Beta-radiation therapy with rhenium 188-filled balloon after rotational atherectomy for diffuse in-stent restenosis was performed in 50 patients. We evaluated the impacts of geographic miss on adjacent coronary artery segments beyond the stent by angiographic (QCA) and intravascular ultrasound (IVUS) analysis in 50 irradiated lesions and 100 edges. Serial IVUS and QCA comparisons between postradiation and 6 months' follow-up were available in 44 and 47 of 50 patients, respectively. QCA measurements of minimal lumen diameter (MLD) and IVUS analysis were performed in the reference and radiation segments. Edges that were touched by the angioplasty balloon but were not adequately covered by radiation constituted the geographic miss edges.
  
  
  RESULTS
  Geographic miss was observed in 55.6% and 52.6% in QCA and IVUS analysis, respectively. Edge restenosis after radiation therapy in 3 patients was associated with geographic miss. In contrast to uninjured edges (postradiation 2.9 +/- 0.6 mm to follow-up 2.8 +/- 0.6 mm, P =.292), MLD in the radiation segment by QCA analysis significantly decreased from 2.7 +/- 0.4 mm to 2.4 +/- 0.6 mm in geographic miss edges (P =.002). IVUS analysis showed that significant positive remodeling in the radiation segment occurred in uninjured edges (vessel area from 15.4 +/- 4.4 mm2 to 15.8 +/- 4.4 mm2, P =.001) but not in geographic miss edges (vessel area from 12.8 +/- 3.6 mm2 to 13.0 +/- 3.6 mm2, P =.119).
  
  
  CONCLUSIONS
  The geographic miss might be one of the predictors, which resulted in decreased MLD at follow-up in beta-radiation therapy. Sufficient lesion coverage with radiation might be associated with positive remodeling in the radiation segment.
authors.affiliation: Department of Medicine, University of Ulsan College of Medicine, Asan Medical Center, Seoul, Korea.
authors.forename: Myeong-Ki
authors.initials: MK
authors.lastname: Hong
authors.forename: Seong-Wook
authors.initials: SW
authors.lastname: Park
authors.forename: Dae-Hyuk
authors.initials: DH
authors.lastname: Moon
authors.forename: Seung-Jun
authors.initials: SJ
authors.lastname: Oh
authors.forename: Eun-Hee
authors.initials: EH
authors.lastname: Kim
authors.forename: Cheol Whan
authors.initials: CW
authors.lastname: Lee
authors.forename: Jong-Min
authors.initials: JM
authors.lastname: Song
authors.forename: Duk-Hyun
authors.initials: DH
authors.lastname: Kang
authors.forename: Jae-Kwan
authors.initials: JK
authors.lastname: Song
authors.forename: Jae-Joong
authors.initials: JJ
authors.lastname: Kim
authors.forename: Seung-Jung
authors.initials: SJ
authors.lastname: Park
mesh_terms: D015906:Angioplasty, Balloon, Coronary; D003324:Coronary Artery Disease / Q000628:therapy; D023903:Coronary Restenosis / Q000000981:diagnostic imaging / Q000532:radiotherapy*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D011446:Prospective Studies; D011859:Radiography; D011868:Radioisotopes / Q000627:therapeutic use*; D012211:Rhenium / Q000627:therapeutic use*; D015607:Stents; D014463:Ultrasonography
chemical_list: D011868:Radioisotopes; D012211:Rhenium