title: Segmental coronary endothelial dysfunction in patients with minimal atherosclerosis is associated with necrotic core plaques.
abstract: OBJECTIVE
  Endothelial dysfunction and atherosclerosis are systemic disorders, but are often characterised by segmental involvement and complications. A potential mechanism for local involvement early in the disease process may be related to plaque composition. This study was designed to test the hypothesis that in patients with minimal coronary atherosclerosis, coronary artery segments with abnormal endothelial function have specific plaque characteristics.
  
  
  METHODS
  Intravascular ultrasound (IVUS) images were obtained from 30 patients who underwent coronary endothelial function assessment. Spectral analysis of the IVUS radiofrequency data was used for assessment of plaque composition. IVUS findings of the coronary sections were compared according to the corresponding endothelial response to acetylcholine.
  
  
  RESULTS
  Sections with a decrease epicardial coronary arterial diameter in response to acetylcholine had smaller baseline lumen (7.5 (2.4) mm(2) vs 8.8 (3.3) mm(2), p = 0.006) but larger plaque burden (37.1% (9.4%) vs 31% (7%), p = 0.003) than sections with normal endothelial response. Sections with endothelial dysfunction had larger necrotic core plaques: 0.13 (0.03-0.33) mm(2) vs 0.0 (0.0-0.07), p<0.001 and more dense calcium: 0.03 (IQR 0.0-0.13) mm(2) vs 0.0 (0.0-0.10) mm(2), p<0.01), than those with normal endothelial response. Only necrotic core area was associated with endothelial dysfunction (p<0.001) after adjusting for other measures.
  
  
  CONCLUSIONS
  This study suggests that local coronary endothelial dysfunction in patients with minimal coronary atherosclerosis is associated with plaque characteristics that are typical of vulnerable plaques.
authors.affiliation: Division of Cardiovascular Diseases and the Center for Coronary Physiology and Imaging, Mayo Clinic, Rochester, MN 55905, USA.
authors.forename: S
authors.initials: S
authors.lastname: Lavi
authors.forename: J-H
authors.initials: JH
authors.lastname: Bae
authors.forename: C S
authors.initials: CS
authors.lastname: Rihal
authors.forename: A
authors.initials: A
authors.lastname: Prasad
authors.forename: G W
authors.initials: GW
authors.lastname: Barsness
authors.forename: R J
authors.initials: RJ
authors.lastname: Lennon
authors.forename: D R
authors.initials: DR
authors.lastname: Holmes
authors.forename: A
authors.initials: A
authors.lastname: Lerman
mesh_terms: D003324:Coronary Artery Disease / Q000000981:diagnostic imaging / Q000473:pathology* / Q000503:physiopathology; D003331:Coronary Vessels / Q000000981:diagnostic imaging / Q000473:pathology* / Q000503:physiopathology; D004730:Endothelium, Vascular / Q000000981:diagnostic imaging / Q000473:pathology / Q000503:physiopathology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009336:Necrosis / Q000000981:diagnostic imaging / Q000473:pathology; D018608:Ultrasonography, Doppler / Q000379:methods