title: Diagnostic accuracy of intraluminal blood speckle intensity on intravascular ultrasound for physiological assessment of coronary artery stenosis.
abstract: OBJECTIVE
  The difference in intraluminal intensity of blood speckle (IBS) on integrated backscatter intravascular ultrasound (IVUS) across the coronary stenosis was reportedly correlated with fractional flow reserve (FFR) in the left descending coronary artery. The aim of this study was to investigate the novel physiological assessment using IVUS in all coronary arteries.
  
  
  METHODS
  Fifty-four patients with 57 coronary lesions underwent both FFR and IVUS. Intraluminal IBS was analyzed using integrated backscatter IVUS in cross-sections at the ostium and the distal site of the target vessel. ΔIBS was calculated as: (distal IBS)-(ostium IBS).
  
  
  RESULTS
  Both ΔIBS (r=-0.50, P<0.01) and minimum lumen area (MLA) (r=0.55, P<0.01) showed significant correlations with FFR. There were significant correlations between FFR and ΔIBS in the right and left descending coronary arteries (r=-0.60, P=0.02, and r=-0.58, P<0.01), but not in the left circumflex (r=0.30, P=0.44). In receiver operating characteristic curve analyses, ΔIBS predicted FFR less than or equal to 0.80 (area under the curve=0.82, P<0.01, best cutoff value=6.78), as with MLA (area under the curve=0.83, P<0.01, best cutoff value=2.38). FFR progressively decreased in association with ΔIBS greater than or equal to 6.78 and MLA less than or equal to 2.38, and was the lowest when these were combined.
  
  
  CONCLUSIONS
  ΔIBS was correlated with FFR in right and left descending coronary arteries. IVUS may assess coronary artery stenosis anatomically and physiologically.
authors.affiliation: Department of Cardiovascular Medicine, Chiba University Graduate School of Medicine, Chiba, Japan.
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Saito
authors.forename: Hideki
authors.initials: H
authors.lastname: Kitahara
authors.forename: Takashi
authors.initials: T
authors.lastname: Nakayama
authors.forename: Yoshihide
authors.initials: Y
authors.lastname: Fujimoto
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Kobayashi
mesh_terms: D000368:Aged; D019540:Area Under Curve; D006328:Cardiac Catheterization; D017023:Coronary Angiography; D023921:Coronary Stenosis / Q000000981:diagnostic imaging* / Q000503:physiopathology; D003331:Coronary Vessels / Q000000981:diagnostic imaging* / Q000503:physiopathology; D005260:Female; D053805:Fractional Flow Reserve, Myocardial; D006801:Humans; D007548:Isosorbide Dinitrate / Q000008:administration & dosage; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D012372:ROC Curve; D015203:Reproducibility of Results; D012189:Retrospective Studies; D012542:Scattering, Radiation; D012720:Severity of Illness Index; D018084:Ultrasonography, Interventional; D014665:Vasodilator Agents / Q000008:administration & dosage
chemical_list: D014665:Vasodilator Agents; D007548:Isosorbide Dinitrate