title: [Mechanism of lumen loss of the left circumflex ostium after main vessel stent implantation: observations by intravascular ultrasound].
abstract: OBJECTIVE
  To explore the mechanism of lumen loss of the left circumflex ostium after main vessel stent implantation.
  
  
  METHODS
  Twenty-eight patients undergoing provisional T technique were enrolled in this study. Intravascular ultrasound (IVUS) examination was performed before and after main vessel stenting and kissing balloon post-dilatation to evaluate the geometrical changes of the vessels.
  
  
  RESULTS
  The CSA of LCX ostium lumen decreased significantly from 5.9∓2 mm(2) to 4.9∓1.9 mm(2) (P<0.01) after the procedure, and the CSA of LCX ostium P and M increased from 5.4∓2.9 mmmm(2) to 5.7∓2.9 mm(2) (P=0.21) after the main vessel stenting. The changes in LCX ostium lumen CSA was correlated with the changes of LCX ostium EEM CSA but not the LCX ostium P and M CSA. After kissing balloon post-dilatation, the CSA of LCX ostium lumen increased from 4.9∓1.9 mm(2) to 5.5∓1.9 mm(2) (P<0.01) , and the CSA of LCX ostium P and M showed no obvious changes (5.7∓2.9 mmmm(2) vs 5.7∓2.6 mmmm(2), P=0.89). The changes of LCX ostium lumen CSA were correlated with the those of the LCX ostium EEM CSA (R=0.432, P=0.02).
  
  
  CONCLUSIONS
  After stent implantation from the LMCA to the LAD, most of lumen losses of the LCX are due to carina shift, and in occasional cases, plaque shift occurs from the distal LMCA to the ostium of the LCX. Kissing balloon technique can adjust carina shift but can not improve plaque shift.
authors.affiliation: Department of Cardiology, Nanfang Hospital, Southern Medical University, Guangzhou, China. xiujc@126.com
authors.forename: Jiancheng
authors.initials: J
authors.lastname: Xiu
authors.forename: Weiming
authors.initials: W
authors.lastname: Liao
authors.forename: Bo
authors.initials: B
authors.lastname: Liu
authors.forename: Xinlu
authors.initials: X
authors.lastname: Zhang
authors.forename: Yuqing
authors.initials: Y
authors.lastname: Hou
authors.forename: Zheng
authors.initials: Z
authors.lastname: Huang
authors.forename: Zhigang
authors.initials: Z
authors.lastname: Guo
authors.forename: Zhongjiang
authors.initials: Z
authors.lastname: Zhou
authors.forename: Shiping
authors.initials: S
authors.lastname: Cao
authors.forename: Kai
authors.initials: K
authors.lastname: Cui
mesh_terms: D000368:Aged; D015906:Angioplasty, Balloon, Coronary; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging* / Q000628:therapy*; D023921:Coronary Stenosis / Q000000981:diagnostic imaging; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015607:Stents; D016896:Treatment Outcome; D018084:Ultrasonography, Interventional