title: Volumetric intravascular ultrasound assessment of mechanisms and results of stent expansion in heart transplant patients.
abstract: BACKGROUND
  Percutaneous coronary intervention with stent placement for the treatment of patients with cardiac allograft vasculopathy is common, but data regarding stent behavior in this setting is lacking.
  
  
  OBJECTIVE
  We investigated mechanisms and potential differences in stent expansion among transplant patients vs. patients with native coronary artery atherosclerotic disease ("controls").
  
  
  METHODS
  We compared pre- and poststent intravascular ultrasound in 12 transplant patients (17 lesions) and 33 control patients (34 lesions) matched according to age (60.1 ± 9.2 years), diabetes mellitus, and lesion location. Planar and volumetric analysis was conducted for every 1 mm at the lesion site as well as the first 5 mm proximal and distal to the stent edge. Focal stent expansion was defined as minimum stent area (MSA) divided by mean reference lumen area. Diffuse stent expansion was defined as mean stent area divided by mean reference lumen area.
  
  
  RESULTS
  Transplant patients had more plaque than "controls" prestenting, but similar MSA and focal and diffuse stent expansion afterwards. The increase in mean lumen area correlated with the increase in mean vessel area in both groups, transplant (R = 0.64, P = 0.008) and controls (R = 0.70, P < 0.0001), but correlated inversely with changes in mean plaque area only in the transplant group (R = 0.55, P = 0.027). There were no differences in calcification between the two groups and no axial plaque distribution from the lesion into the reference segments in either group.
  
  
  CONCLUSIONS
  The mechanism of stent expansion in transplant vasculopathy appears to be similar to de novo atherosclerosis-i.e., mainly vessel expansion to achieve similar acute results.
authors.affiliation: Center for Interventional Vascular Therapy, Columbia University Medical Center, New York, NY, USA.
authors.forename: Elias A
authors.initials: EA
authors.lastname: Sanidas
authors.forename: Akiko
authors.initials: A
authors.lastname: Maehara
authors.forename: Gary S
authors.initials: GS
authors.lastname: Mintz
authors.forename: Takashi
authors.initials: T
authors.lastname: Kubo
authors.forename: Anuj
authors.initials: A
authors.lastname: Gupta
authors.forename: Mark A
authors.initials: MA
authors.lastname: Apfelbaum
authors.forename: Diaa
authors.initials: D
authors.lastname: Hakim
authors.forename: Jeffrey W
authors.initials: JW
authors.lastname: Moses
authors.forename: Donna M
authors.initials: DM
authors.lastname: Mancini
authors.forename: Leroy E
authors.initials: LE
authors.lastname: Rabbani
mesh_terms: D003324:Coronary Artery Disease / Q000000981:diagnostic imaging* / Q000209:etiology / Q000601:surgery; D003331:Coronary Vessels / Q000000981:diagnostic imaging* / Q000601:surgery; D005260:Female; D006333:Heart Failure / Q000601:surgery; D016027:Heart Transplantation / Q000009:adverse effects* / Q000000981:diagnostic imaging; D006801:Humans; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative / Q000379:methods*; D062645:Percutaneous Coronary Intervention / Q000379:methods*; D011183:Postoperative Complications; D012086:Reoperation; D012189:Retrospective Studies; D015607:Stents; D014184:Transplantation, Homologous; D016896:Treatment Outcome; D018084:Ultrasonography, Interventional / Q000379:methods*