title: Pattern of instent neointimal formation compared to native atherosclerosis in the coronary bifurcation lesions: volumetric intravascular ultrasound analysis.
abstract: BACKGROUND
  No clinical study has systematically analyzed and compared circumferential neointimal and plaque distribution of stent neointimal proliferation and in native atherosclerotic plaques. This study aimed to investigate and compare the pattern of instent neointimal formation and native atherosclerosis in the coronary bifurcation lesions by volumetric analysis using systematic intravascular ultrasound (IVUS).
  
  
  METHODS
  We examined bifurcation lesions in native coronary artery (plaque group, n = 102) and stented bifurcations at 9-month follow-up (neointima group, n = 51) using volumetric IVUS analysis of both the main vessel (MV) and side branch (SB). Three 5-mm segments were analyzed; the proximal MV (MVp), distal MV (MVd) and SB ostium (SBo). For each segment, volumetric analysis was performed in each of four quadrants (divided according to the branch takeoff and the geometric center of the lumen); carinal, epicardial, abcarinal, and myocardial. The eccentricity index was defined as the ratio of the abcarinal plaque (or neointimal) volume to the carinal plaque (or neointimal) volume.
  
  
  RESULTS
  The plaque distribution differed significantly between the four quadrants, with the largest in the abcarinal quadrant, followed by the myocardial, epicardial, and carinal quadrants. The distribution of neointima was similar in the MV, but the four quadrants in the SB did not differ significantly. The eccentricity indices of both the MVd (P < 0.001) and SBo (P = 0.001) were significantly higher for the plaque group than the neointima group.
  
  
  CONCLUSIONS
  The distribution of neointimal proliferation seems to have a similar pattern to that of atherosclerotic plaque in native coronary arteries, particularly in the main vessel, but the trend is less prominent.
authors.affiliation: Division of Cardiology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea; Cardiovascular Center, Tianjin First Central Hospital, Tianjin 300192 , China.
authors.forename: Jian-Qiang
authors.initials: JQ
authors.lastname: Xu
authors.forename: Young Bin
authors.initials: YB
authors.lastname: Song
authors.forename: Joo-Yong
authors.initials: JY
authors.lastname: Hahn
authors.forename: Seung-Hyuk
authors.initials: SH
authors.lastname: Choi
authors.forename: Jin-Ho
authors.initials: JH
authors.lastname: Choi
authors.forename: Cheng-Zhi
authors.initials: CZ
authors.lastname: Lu
authors.forename: Sang Hoon
authors.initials: SH
authors.lastname: Lee
authors.forename: Kyung Pyo
authors.initials: KP
authors.lastname: Hong
authors.forename: Jeung Euy
authors.initials: JE
authors.lastname: Park
authors.forename: Hyeon-Cheol
authors.initials: HC
authors.lastname: Gwon
mesh_terms: D000368:Aged; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D058426:Neointima / Q000000981:diagnostic imaging*; D058226:Plaque, Atherosclerotic / Q000000981:diagnostic imaging; D014463:Ultrasonography