title: Quantitative angiography and optical coherence tomography for the functional assessment of nonobstructive coronary stenoses: comparison with fractional flow reserve.
abstract: BACKGROUND
  The purpose was to compare 3-dimensional quantitative coronary angiography (3D-QCA) with optical coherence tomography (OCT) for the functional assessment of nonobstructive coronary stenoses, as evaluated by fractional flow reserve (FFR).
  
  
  METHODS
  Fifty-five nonobstructive coronary stenoses (30%-50% diameter stenosis by visual estimation) were assessed in 36 patients using FFR, 2-dimensional QCA (2D-QCA), 3D-QCA, and OCT.
  
  
  RESULTS
  Angiographic stenosis severity by 2D-QCA was 34% ± 13% diameter stenosis, and minimal lumen diameter (MLD) was 1.77 ± 0.58 mm. Fractional flow reserve values were 0.85 ± 0.10. Correlation coefficients between FFR and MLD or minimal lumen area (MLA) were highly significant for both 2D- and 3D-QCA (all P < .001), but higher R(2) values were observed for 3D-QCA measurements. Although significant, correlation coefficients between OCT and FFR data were weak (R(2) = 0.28, P = .001 for MLD and R(2) = 0.23, P = .003 for MLA). Correlation coefficients with FFR were significantly higher for 3D-QCA than for OCT (P values for MLD and MLA = .043 and .042, respectively). Nonobstructive stenoses with MLD >1.53 mm or MLA >2.43 mm(2) are unlikely to be hemodynamically significant.
  
  
  CONCLUSIONS
  In nonobstructive coronary stenoses, anatomical parameters derived from 3D-QCA can best identify lesions with preserved FFR values.
authors.affiliation: Cardiovascular Center Aalst, OLV Clinic, Aalst, Belgium.
authors.forename: Stylianos A
authors.initials: SA
authors.lastname: Pyxaras
authors.forename: Shengxian
authors.initials: S
authors.lastname: Tu
authors.forename: Emanuele
authors.initials: E
authors.lastname: Barbato
authors.forename: Giulia
authors.initials: G
authors.lastname: Barbati
authors.forename: Luigi
authors.initials: L
authors.lastname: Di Serafino
authors.forename: Frederic
authors.initials: F
authors.lastname: De Vroey
authors.forename: Gabor
authors.initials: G
authors.lastname: Toth
authors.forename: Fabio
authors.initials: F
authors.lastname: Mangiacapra
authors.forename: Gianfranco
authors.initials: G
authors.lastname: Sinagra
authors.forename: Bernard
authors.initials: B
authors.lastname: De Bruyne
authors.forename: Johan H C
authors.initials: JH
authors.lastname: Reiber
authors.forename: William
authors.initials: W
authors.lastname: Wijns
mesh_terms: D000368:Aged; D006328:Cardiac Catheterization; D017023:Coronary Angiography; D023921:Coronary Stenosis / Q000175:diagnosis* / Q000503:physiopathology; D005260:Female; D053805:Fractional Flow Reserve, Myocardial; D006801:Humans; D021621:Imaging, Three-Dimensional; D008297:Male; D008875:Middle Aged; D012720:Severity of Illness Index; D041623:Tomography, Optical Coherence