title: Correlation between fractional flow reserve and intravascular ultrasound lumen area in intermediate coronary artery stenosis.
abstract: OBJECTIVE
  Fractional flow reserve (FFR) of <0.8 or 0.75 is currently used to guide revascularisation in lesions with intermediate coronary stenosis. We assessed whether there is an intravascular ultrasound (IVUS) measurement that can reliably be used to predict when patients should undergo intervention.
  
  
  RESULTS
  The analysis included 92 intermediate lesions (84 patients) located in vessel diameters >2.5 mm. Positive FFR was considered present at <0.8 and 0.75. IVUS minimum lumen area (MLA) was correlated to the FFR findings in intermediate lesions with 40-70% stenosis. The mean FFR value was 0.89 ± 0.08. Twenty-four patients (26.1%) had FFR <0.8; 17 (18.5%) <0.75. Positive correlations between FFR and IVUS measurements included MLA (r = 0.34, p<0.001), minimum lumen diameter (MLD) (r=0.31, p=0.004), lesion length (r=-0.5, p<0.001), and area stenosis (r=-0.31, p=0.01). There was no significant correlation between FFR and quantitative coronary angiography in MLD (r=0.19, p=0.06), diameter stenosis (r=0.08, p=0.4), or lesion length (r=-0.14, p=0.17). A receiver operating characteristic curve identified MLA <2.8 mm2 (sensitivity 79.7%, specificity 80.3%) as the best threshold value for FFR <0.75; and MLA <3.2 mm2 as best for FFR <0.8 (sensitivity 69.2%, specificity 68.3%).
  
  
  CONCLUSIONS
  Anatomic measurements of intermediate coronary lesions obtained by IVUS show a moderate correlation to FFR values, although they differ according to vessel size. IVUS MLA may be used as an alternative to FFR when assessing the need for intervention in intermediate coronary lesion. Vessel size, however, should always be taken into account.
authors.affiliation: Division of Cardiology, Washington Hospital Center, Washington, DC 20010, USA.
authors.forename: Itsik
authors.initials: I
authors.lastname: Ben-Dor
authors.forename: Rebecca
authors.initials: R
authors.lastname: Torguson
authors.forename: Michael A
authors.initials: MA
authors.lastname: Gaglia
authors.forename: Manuel A
authors.initials: MA
authors.lastname: Gonzalez
authors.forename: Gabriel
authors.initials: G
authors.lastname: Maluenda
authors.forename: Anh B
authors.initials: AB
authors.lastname: Bui
authors.forename: Zhenyi
authors.initials: Z
authors.lastname: Xue
authors.forename: Lowell F
authors.initials: LF
authors.lastname: Satler
authors.forename: William O
authors.initials: WO
authors.lastname: Suddath
authors.forename: Joseph
authors.initials: J
authors.lastname: Lindsay
authors.forename: Augusto D
authors.initials: AD
authors.lastname: Pichard
authors.forename: Ron
authors.initials: R
authors.lastname: Waksman
mesh_terms: D000328:Adult; D000368:Aged; D017023:Coronary Angiography; D003326:Coronary Circulation; D023921:Coronary Stenosis / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D018084:Ultrasonography, Interventional