title: Impact of atherosclerotic plaque components and their distribution on stent deployment: an intravascular-ultrasound virtual histology observational study.
abstract: BACKGROUND
  The aim of this study was to evaluate how the spatial distribution of each plaque element, defined by intravascular-ultrasound virtual histology (IVUS-VH), may affect stent deployment even at high inflation pressures.
  
  
  METHODS
  Thirty-two patients undergoing direct percutaneous coronary intervention and IVUS were evaluated. Fifty-two lesions were treated with drug-eluting stents. Pre-stenting lumen area and real (Rcssla) and average cross-sectional stent lumen area (Acssla) were measured along the whole lesion. Ideal cross-sectional stent lumen area (Icssla) was calculated. Plaque composition was characterized by IVUS-VH. The spatial distribution of each plaque element was quantified by a novel image analysis tool measuring the area and percentage of each plaque component that was adjacent to the lumen. Average stent deployment was defined as: [1 - (Icssla-Acssla)/Icssla]×100%.
  
  
  RESULTS
  Stent expansion was significantly less at the site of maximum calcification compared to the average stent deployment (80±9% vs. 85±13%, P=0.044, respectively). Furthermore, wherever calcium was adjacent to the lumen, stent expansion was impaired compared to sites where calcium was non-luminal (70±23% vs. 80±9%, P=0.01, respectively). In contrast, at the site of maximum necrotic core, stent deployment showed a trend to be less compromised, compared to the average stent deployment.
  
  
  CONCLUSIONS
  An interaction was found between plaque components and their distribution and stent deployment even at high inflation pressures.
authors.affiliation: First Department of Cardiology, Hippokration Hospital, Medical School, National and Kapodistrian University of Athens, Athens, Greece - vavouran@otenet.gr.
authors.forename: Manolis
authors.initials: M
authors.lastname: Vavuranakis
authors.forename: Theodore G
authors.initials: TG
authors.lastname: Papaioannou
authors.forename: Ourania A
authors.initials: OA
authors.lastname: Katsarou
authors.forename: Dimitrios A
authors.initials: DA
authors.lastname: Vrachatis
authors.forename: Elias A
authors.initials: EA
authors.lastname: Sanidas
authors.forename: Gerasimos
authors.initials: G
authors.lastname: Siasos
authors.forename: Konstantinos I
authors.initials: KI
authors.lastname: Kalogeras
authors.forename: Dimitrios
authors.initials: D
authors.lastname: Schizas
authors.forename: Christodoulos I
authors.initials: CI
authors.lastname: Stefanadis
authors.forename: Dimitris
authors.initials: D
authors.lastname: Tousoulis
mesh_terms: D000368:Aged; D002114:Calcinosis / Q000000981:diagnostic imaging / Q000601:surgery; D017023:Coronary Angiography; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging / Q000601:surgery; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D062645:Percutaneous Coronary Intervention; D058226:Plaque, Atherosclerotic / Q000000981:diagnostic imaging*; D015607:Stents; D018084:Ultrasonography, Interventional / Q000379:methods*