title: Stent underexpansion in angiographic guided percutaneous coronary intervention, despite adjunctive balloon post-dilatation, in drug eluting stent era.
abstract: BACKGROUND
  Stent underexpansion is the most powerful predictor of long-term stent patency and clinical outcome. The purpose of this study was to evaluate the incidence and predictors of stent underexpansion despite adjunctive post-dilatation with non-compliant balloon.
  
  
  METHODS
  After elective coronary stent implantation and adjunctive post-dilatation with non-compliant balloon and optimal angiographic result confirmed by the operator, intravascular ultrasound (IVUS) was performed for all the treated lesions. If the treated lesions fulfilled the IVUS criteria, they are considered as the optimal stent group; if not, they are considered as the suboptimal group.
  
  
  RESULTS
  From 50 patients enrolled in this study 39 (78%) had optimal stent deployment and 11 (22%) had suboptimal stent deployment. In the suboptimal group 7 (14%) had underexpansion, 2 (4%) malposition, and 2 (4%) had asymmetry. There were no stent edge dissections detected by IVUS. We did not find any correlation between lesion calcification, ostial lesions, stent length, and stent underexpansion. Stent diameter ≤ 2.75 mm had a strong correlation with stent underexpansion.
  
  
  CONCLUSIONS
  Despite adjunctive post-dilatation with noncompliant balloon, using a relatively small stent diameter was a strong predictor for underexpansion. IVUS guided percutaneous coronary intervention (PCI) may be considered for drug eluting stent (DES) implantation in relatively small vessels.
authors: Cardiac Rehabilitation Research Centre, Isfahan Cardiovascular Research Institute, Isfahan University of Medical Sciences, Isfahan, Iran.
authors: Mehrdad
authors: M
authors: Taherioun
authors: Associate Professor, Cardiovascular Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors: Mohammad Hassan
authors: MH
authors: Namazi
authors: Associate Professor, Cardiovascular Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors: Morteza
authors: M
authors: Safi
authors: Professor, Cardiovascular Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors: Habibolah
authors: H
authors: Saadat
authors: Associate Professor, Cardiovascular Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors: Hossein
authors: H
authors: Vakili
authors: Assistant Professor, Cardiovascular Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors: Saeed
authors: S
authors: Alipour-Parsa
authors: Assistant Professor, Kashan University of Medical Sciences, Kashan, Iran.
authors: Hasan
authors: H
authors: Rajabi-Moghadam
authors: Cardiac Rehabilitation Research Centre, Isfahan Cardiovascular Research Institute, Isfahan University of Medical Sciences, Isfahan, Iran.
authors: Shamsedin
authors: S
authors: Pedari
keywords: Percutaneous Coronary Intervention; Post-dilatation; Stent; Ultrasound