title: Combined IVUS and NIRS detection of fibroatheromas: histopathological validation in human coronary arteries.
abstract: OBJECTIVE
  This study assessed grayscale intravascular ultrasound (IVUS) and near-infrared spectroscopy (NIRS) detection of a histological fibroatheroma (FA).
  
  
  BACKGROUND
  NIRS-detected, lipid-rich plaques (LRPs) and IVUS-detected attenuated plaques are considered to be vulnerable.
  
  
  METHODS
  IVUS-attenuated plaque and NIRS-LRP (yellow or tan block chemogram) were compared with histopathology in 1,943 sections of 103 coronary arteries from 56 autopsied hearts.
  
  
  RESULTS
  IVUS-superficial attenuation and NIRS-LRP showed a similar high specificity of approximately 95%, whereas IVUS-superficial attenuation alone had a poor sensitivity (vs. NIRS-LRP) in detecting FAs (36% vs. 47%; p = 0.001). Compared with FA sections with superficial attenuation, FA sections without superficial attenuation had a smaller plaque burden (57.1% vs. 67.7%), a larger arc of calcium (79.7° vs. 16.8°), and a lower prevalence of a ≥20% histological necrotic core (28% vs. 50%) or late FA (14% vs. 37%; all p < 0.05). Compared with FA sections with NIRS-LRP, FA sections without NIRS-LRP showed a smaller plaque burden (58.0% vs. 63.3%) and a lower prevalence of a ≥20% necrotic core (27% vs. 46%). Conversely, non-FAs with NIRS-LRP (vs. non-FAs without LRP) showed a larger plaque burden (55.1% vs. 46.3%), a greater prevalence of a ≥20% histological lipid pool (34% vs. 5%), and mostly pathological intimal thickening (50%) or fibrocalcific plaque (33%). When sections showed either IVUS attenuation or NIRS-LRP, the sensitivity for predicting a FA was significantly higher compared with IVUS attenuation alone (63% vs. 36%; p < 0.001) or NIRS-LRP alone (63% vs. 47%; p < 0.001). When sections showed both IVUS attenuation and NIRS-LRP, the positive predictive value improved compared with IVUS attenuation alone (84% vs. 66%; p < 0.001) or NIRS-LRP alone (84% vs. 65%; p < 0.001).
  
  
  CONCLUSIONS
  NIRS-LRP was more accurate than IVUS for predicting plaque containing a necrotic core or a large lipid pool, and the combination was more accurate than either alone.
authors.affiliation: Columbia University Medical Center, New York, New York; Cardiovascular Research Foundation, New York, New York.
authors.forename: Soo-Jin
authors.initials: SJ
authors.lastname: Kang
authors.affiliation: Cardiovascular Research Foundation, New York, New York.
authors.forename: Gary S
authors.initials: GS
authors.lastname: Mintz
authors.affiliation: Columbia University Medical Center, New York, New York; Cardiovascular Research Foundation, New York, New York.
authors.forename: Jun
authors.initials: J
authors.lastname: Pu
authors.affiliation: InfraReDx, Inc., Burlington, Massachusetts.
authors.forename: Stephen T
authors.initials: ST
authors.lastname: Sum
authors.affiliation: InfraReDx, Inc., Burlington, Massachusetts.
authors.forename: Sean P
authors.initials: SP
authors.lastname: Madden
authors.affiliation: University of Maryland Medical Center, Baltimore, Maryland; CVPath Institute, Gaithersburg, Maryland.
authors.forename: Allen P
authors.initials: AP
authors.lastname: Burke
authors.affiliation: Cardiovascular Research Foundation, New York, New York.
authors.forename: Ke
authors.initials: K
authors.lastname: Xu
authors.affiliation: Division of Cardiology, William Beaumont Hospital, Royal Oak, Michigan.
authors.forename: James A
authors.initials: JA
authors.lastname: Goldstein
authors.affiliation: Columbia University Medical Center, New York, New York; Cardiovascular Research Foundation, New York, New York.
authors.forename: Gregg W
authors.initials: GW
authors.lastname: Stone
authors.affiliation: InfraReDx, Inc., Burlington, Massachusetts.
authors.forename: James E
authors.initials: JE
authors.lastname: Muller
authors.affiliation: CVPath Institute, Gaithersburg, Maryland.
authors.forename: Renu
authors.initials: R
authors.lastname: Virmani
authors.affiliation: Columbia University Medical Center, New York, New York; Cardiovascular Research Foundation, New York, New York. Electronic address: amaehara@crf.org.
authors.forename: Akiko
authors.initials: A
authors.lastname: Maehara
mesh_terms: D000368:Aged; D003324:Coronary Artery Disease / Q000175:diagnosis*; D003331:Coronary Vessels / Q000000981:diagnostic imaging* / Q000473:pathology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D058226:Plaque, Atherosclerotic / Q000175:diagnosis*; D011237:Predictive Value of Tests; D012720:Severity of Illness Index; D019265:Spectroscopy, Near-Infrared / Q000379:methods*; D018084:Ultrasonography, Interventional / Q000379:methods*
keywords: fibroatheroma; imaging; intravascular ultrasound; near-infrared spectroscopy