title: Optimal intravascular ultrasound criteria and their accuracy for defining the functional significance of intermediate coronary stenoses of different locations.
abstract: OBJECTIVE
  We performed this study to determine the optimal intravascular ultrasound (IVUS) criteria and to evaluate their accuracy for defining the functional significance of intermediate coronary stenoses in different locations of the coronary tree.
  
  
  BACKGROUND
  Presence of myocardial ischemia is the most important prognostic factor in patients with coronary artery disease and is determined by both the lesion severity and the amount of myocardium supplied.
  
  
  METHODS
  IVUS and fractional flow reserve (FFR) measurements were performed in 267 intermediate lesions located at the proximal or mid part of major epicardial coronary arteries. Optimal IVUS criteria and their diagnostic accuracy for functionally significant stenoses (FFR <0.8) were assessed.
  
  
  RESULTS
  FFR was <0.8 in 88 lesions (33%). The determinants of FFR were minimum lumen area (MLA) and lesion location. The diagnostic accuracy of MLA was highly variable according to the location of lesions. The best cutoff value of MLA to define the functional significance was 3.0 mm(2) (area under the curve [AUC]: 0.81, 95% confidence interval [CI]: 0.68 to 0.91) for proximal left anterior descending artery (LAD) lesions and 2.75 mm(2) for mid-LAD lesions located before the second diagonal branch (AUC: 0.76, 95% CI: 0.66 to 0.84). However, the appropriate MLA to predict the functional significance of lesions could not be found in other segments.
  
  
  CONCLUSIONS
  When IVUS parameters are used to determine the functional significance of lesions in patients with intermediate coronary artery stenoses, different criteria should be used according to lesion location. In segments or vessels with anatomic variations, IVUS cannot be used for functional assessment of a stenosis. (Comparison of Fractional Flow Reserve and Intravascular Ultrasound; NCT01133015).
authors.affiliation: Department of Internal Medicine, Seoul National University Hospital, Seoul, Korea.
authors.forename: Bon-Kwon
authors.initials: BK
authors.lastname: Koo
authors.forename: Hyoung-Mo
authors.initials: HM
authors.lastname: Yang
authors.forename: Jun-Hyung
authors.initials: JH
authors.lastname: Doh
authors.forename: Hyunmin
authors.initials: H
authors.lastname: Choe
authors.forename: Sung-Yun
authors.initials: SY
authors.lastname: Lee
authors.forename: Chang-Hwan
authors.initials: CH
authors.lastname: Yoon
authors.forename: Yun-Kyeong
authors.initials: YK
authors.lastname: Cho
authors.forename: Chang-Wook
authors.initials: CW
authors.lastname: Nam
authors.forename: Seung-Ho
authors.initials: SH
authors.lastname: Hur
authors.forename: Hong-Seok
authors.initials: HS
authors.lastname: Lim
authors.forename: Myeong-Ho
authors.initials: MH
authors.lastname: Yoon
authors.forename: Kyung-Woo
authors.initials: KW
authors.lastname: Park
authors.forename: Sang-Hoon
authors.initials: SH
authors.lastname: Na
authors.forename: Tae-Jin
authors.initials: TJ
authors.lastname: Youn
authors.forename: Woo-Young
authors.initials: WY
authors.lastname: Chung
authors.forename: Seunghyun
authors.initials: S
authors.lastname: Ma
authors.forename: Sue-Kyung
authors.initials: SK
authors.lastname: Park
authors.forename: Hyo-Soo
authors.initials: HS
authors.lastname: Kim
authors.forename: Seung-Jea
authors.initials: SJ
authors.lastname: Tahk
mesh_terms: D017023:Coronary Angiography; D003326:Coronary Circulation / Q000502:physiology*; D023921:Coronary Stenosis / Q000000981:diagnostic imaging* / Q000503:physiopathology; D003331:Coronary Vessels / Q000000981:diagnostic imaging* / Q000503:physiopathology; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D011446:Prospective Studies; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D018084:Ultrasonography, Interventional / Q000592:standards*; D014655:Vascular Resistance / Q000502:physiology*