title: Fractional flow reserve compared with intravascular ultrasound guidance for optimizing stent deployment.
abstract: BACKGROUND
  Determination of fractional flow reserve (FFR) has been proposed as a means to assess stent deployment. In this prospective, multicenter trial, we evaluate the use of FFR to optimize stenting by comparing it with standard intravascular ultrasound (IVUS) criteria.
  
  
  RESULTS
  Eighty-four stable patients with isolated coronary lesions underwent coronary stent deployment starting at 10 atm and increased serially by 2 atm until the FFR was >/=0.94 or 16 atm was achieved. IVUS was then performed. FFR was measured with a coronary pressure wire with intracoronary adenosine to induce hyperemia. The diagnostic characteristics of an FFR <0.94 to predict suboptimal stent expansion by IVUS, defined in both absolute and relative terms, were calculated. Over a range of IVUS criteria, the highest sensitivity, specificity, and predictive accuracy of FFR were 80%, 30%, and 42%, respectively. Receiver operator characteristic analysis defined an optimal FFR cut point at >/=0.96; at this threshold, the sensitivity, specificity, and predictive accuracy of FFR were 75%, 58%, and 62%, respectively (P=0.03 for comparison of predictive accuracy, P=0.01 for concordance between FFR and IVUS). The negative predictive value was 88%. Significantly better diagnostic performance was achieved in a subgroup that received higher doses (>30 microgram) of intracoronary adenosine during pressure measurements, suggesting that FFR might be overestimated in the other group.
  
  
  CONCLUSIONS
  A fractional flow reserve <0.96, measured after stent deployment, predicts a suboptimal result based on validated intravascular ultrasound criteria; however, an FFR >/=0.96 does not reliably predict an optimal stent result. Higher doses of intracoronary adenosine than previously used to measure FFR improve these results.
authors.affiliation: Stanford University Medical Center, Stanford, CA, USA. wfearon@stanford.edu
authors.forename: W F
authors.initials: WF
authors.lastname: Fearon
authors.forename: J
authors.initials: J
authors.lastname: Luna
authors.forename: H
authors.initials: H
authors.lastname: Samady
authors.forename: E R
authors.initials: ER
authors.lastname: Powers
authors.forename: T
authors.initials: T
authors.lastname: Feldman
authors.forename: N
authors.initials: N
authors.lastname: Dib
authors.forename: E M
authors.initials: EM
authors.lastname: Tuzcu
authors.forename: M W
authors.initials: MW
authors.lastname: Cleman
authors.forename: T M
authors.initials: TM
authors.lastname: Chou
authors.forename: D J
authors.initials: DJ
authors.lastname: Cohen
authors.forename: M
authors.initials: M
authors.lastname: Ragosta
authors.forename: A
authors.initials: A
authors.lastname: Takagi
authors.forename: A
authors.initials: A
authors.lastname: Jeremias
authors.forename: P J
authors.initials: PJ
authors.lastname: Fitzgerald
authors.forename: A C
authors.initials: AC
authors.lastname: Yeung
authors.forename: M J
authors.initials: MJ
authors.lastname: Kern
authors.forename: P G
authors.initials: PG
authors.lastname: Yock
mesh_terms: D000241:Adenosine; D015906:Angioplasty, Balloon, Coronary / Q000379:methods*; D001783:Blood Flow Velocity; D019917:Blood Vessel Prosthesis Implantation / Q000379:methods*; D017023:Coronary Angiography; D003324:Coronary Artery Disease / Q000175:diagnosis* / Q000503:physiopathology / Q000601:surgery*; D003326:Coronary Circulation; D003331:Coronary Vessels / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery; D005260:Female; D006801:Humans; D016013:Likelihood Functions; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012372:ROC Curve; D012680:Sensitivity and Specificity; D015607:Stents; D016896:Treatment Outcome; D018084:Ultrasonography, Interventional
chemical_list: D000241:Adenosine