title: Anatomic and functional evaluation of bifurcation lesions undergoing percutaneous coronary intervention.
abstract: BACKGROUND
  We sought to investigate the mechanism of geometric changes after main branch (MB) stent implantation and to identify the predictors of functionally significant "jailed" side branch (SB) lesions.
  
  
  RESULTS
  Seventy-seven patients with bifurcation lesions were prospectively enrolled from 8 centers. MB intravascular ultrasound was performed before and after MB stent implantation, and fractional flow reserve was measured in the jailed SB. The vessel volume index of both the proximal and distal MB was increased after stent implantation. The plaque volume index decreased in the proximal MB (9.1+/-3.0 to 8.4+/-2.4 mm(3)/mm, P=0.001), implicating plaque shift, but not in the distal MB (5.4+/-1.8 to 5.3+/-1.7 mm(3)/mm, P=0.227), implicating carina shifting to account for the change in vessel size (N=56). The mean SB fractional flow reserve was 0.71+/-0.20 (N=68) and 43% of the lesions were functionally significant. Binary logistic-regression analysis revealed that preintervention % diameter stenosis of the SB (odds ratio=1.05; 95% CI, 1.01 to 1.09) and the MB minimum lumen diameter located distal to the SB ostium (odds ratio=3.86; 95% CI, 1.03 to 14.43) were independent predictors of functionally significant SB jailing. In patients with > or =75% stenosis and Thrombolysis In Myocardial Infarction grade 3 flow in the SB, no difference in post-stent angiographic and intravascular ultrasound parameters was found between SB lesions with and without functional significance.
  
  
  CONCLUSIONS
  Both plaque shift from the MB and carina shift contribute to the creation/aggravation of an SB ostial lesion after MB stent implantation. Anatomic evaluation does not reliably predict the functional significance of a jailed SB stenosis.
authors.affiliation: Division of Cardiovascular Medicine, Interventional Cardiology, Stanford University Medical Center, 300 Pasteur Drive, Stanford, CA 94305, USA.
authors.forename: Bon-Kwon
authors.initials: BK
authors.lastname: Koo
authors.forename: Katsuhisa
authors.initials: K
authors.lastname: Waseda
authors.forename: Hyun-Jae
authors.initials: HJ
authors.lastname: Kang
authors.forename: Hyo-Soo
authors.initials: HS
authors.lastname: Kim
authors.forename: Chang-Wook
authors.initials: CW
authors.lastname: Nam
authors.forename: Seung-Ho
authors.initials: SH
authors.lastname: Hur
authors.forename: Jung-Sun
authors.initials: JS
authors.lastname: Kim
authors.forename: Donghoon
authors.initials: D
authors.lastname: Choi
authors.forename: Yangsoo
authors.initials: Y
authors.lastname: Jang
authors.forename: Joo-Yong
authors.initials: JY
authors.lastname: Hahn
authors.forename: Hyeon-Cheol
authors.initials: HC
authors.lastname: Gwon
authors.forename: Myeong-Ho
authors.initials: MH
authors.lastname: Yoon
authors.forename: Seung-Jea
authors.initials: SJ
authors.lastname: Tahk
authors.forename: Woo-Young
authors.initials: WY
authors.lastname: Chung
authors.forename: Young-Seok
authors.initials: YS
authors.lastname: Cho
authors.forename: Dong-Ju
authors.initials: DJ
authors.lastname: Choi
authors.forename: Takao
authors.initials: T
authors.lastname: Hasegawa
authors.forename: Toru
authors.initials: T
authors.lastname: Kataoka
authors.forename: Sung Jin
authors.initials: SJ
authors.lastname: Oh
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Honda
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Fitzgerald
authors.forename: William F
authors.initials: WF
authors.lastname: Fearon
mesh_terms: D000368:Aged; D015906:Angioplasty, Balloon, Coronary / Q000009:adverse effects; D019917:Blood Vessel Prosthesis Implantation / Q000009:adverse effects; D003324:Coronary Artery Disease / Q000150:complications / Q000175:diagnosis / Q000473:pathology / Q000628:therapy*; D023921:Coronary Stenosis / Q000175:diagnosis / Q000209:etiology* / Q000473:pathology*; D005260:Female; D053805:Fractional Flow Reserve, Myocardial; D006801:Humans; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications; D011446:Prospective Studies; D018084:Ultrasonography, Interventional