title: Acute lumen overdilation improves outcome after brachytherapy of in-stent restenosis.
abstract: BACKGROUND
  The aim of our study was to test the impact of acute lumen overdilation on neointimal hyperplasia and late lumen size after vascular brachytherapy for in-stent restenosis (ISR).
  
  
  METHODS
  Forty-seven ISR lesions located in 47 coronary arteries in 44 consecutive patients underwent beta brachytherapy with serial intravascular ultrasound studies. Vessel, lumen, and stent cross-sectional area were measured at 1-mm steps. Based on an interpolated reference cross-sectional area, each cross section was assessed as overdilated (lumen cross-sectional area>interpolated reference cross-sectional area) or not overdilated (lumen cross-sectional area <interpolated reference cross-sectional area).
  
  
  RESULTS
  Overall, 502 sections were overdilated and 673 sections were not. Overdilated sections had a larger final lumen cross-sectional area (8.02+/-1.98 vs. 6.90+/-2.23 mm2, P<.001) and more recurrent neointimal hyperplasia (1.59+/-2.17 vs. 0.31+/-1.79 mm2, P<.001), but a smaller follow-up area stenosis (-1.03+/-32.99% vs. 22.15+/-20.75%, P<.001). This was especially true in smaller arteries (angiographic reference<3.0 mm) where larger follow-up lumen cross-sectional area and a corresponding smaller area stenosis were present (5.38+/-1.98 vs. 4.84+/-1.88 mm2 and 6.90+/-31.57% vs. 28.61+/-21.86%, P<.01 and P<.001, respectively).
  
  
  CONCLUSIONS
  Especially in small arteries, the strategy of acute lumen overdilation during balloon angioplasty prior to beta vascular brachytherapy treatment of ISR lesions has a favorable long-term result.
authors.affiliation: Haemodynamics Department, Institute of Cardiology, Warsaw, Poland. witkowski@hbz.pl
authors.forename: Adam
authors.initials: A
authors.lastname: Witkowski
authors.forename: Łukasz
authors.initials: Ł
authors.lastname: Kalińczuk
authors.forename: Zbigniew
authors.initials: Z
authors.lastname: Chmielak
authors.forename: Jerzy
authors.initials: J
authors.lastname: Pregowski
authors.forename: Jarosław
authors.initials: J
authors.lastname: Łyczek
authors.forename: Maria
authors.initials: M
authors.lastname: Kawczyńska
authors.forename: Wojciech
authors.initials: W
authors.lastname: Bulski
authors.forename: Anna
authors.initials: A
authors.lastname: Kulik
authors.forename: Stanisław
authors.initials: S
authors.lastname: Pszona
authors.forename: Cezary
authors.initials: C
authors.lastname: Kepka
authors.forename: Jakub
authors.initials: J
authors.lastname: Przyłuski
authors.forename: Jacek
authors.initials: J
authors.lastname: Owczarczyk
authors.forename: Witold
authors.initials: W
authors.lastname: Ruzyłło
mesh_terms: D000800:Angioplasty, Balloon; D001918:Brachytherapy / Q000379:methods*; D017023:Coronary Angiography; D023903:Coronary Restenosis / Q000000981:diagnostic imaging / Q000532:radiotherapy* / Q000628:therapy; D004108:Dilatation, Pathologic; D005260:Female; D006801:Humans; D006965:Hyperplasia; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D012008:Recurrence; D012189:Retrospective Studies; D015607:Stents; D016896:Treatment Outcome; D017539:Tunica Intima / Q000000981:diagnostic imaging / Q000473:pathology / Q000528:radiation effects*; D018084:Ultrasonography, Interventional