title: Possible association between non-invasive parameter of flow-mediated dilatation in brachial artery and whole coronary plaque vulnerability in patients with coronary artery disease.
abstract: BACKGROUND
  Despite being a relatively widely-used non-invasive parameter of endothelial dysfunction, little is known regarding the relationship between flow-mediated dilatation (FMD) and coronary plaque vulnerability in patients with coronary artery disease (CAD).
  
  
  METHODS
  111 CAD patients (age; 68.9 ± 9.3) who underwent both coronary intervention and FMD were enrolled. Spectral analyses of intravascular ultrasound radiofrequency data for both culprit and non-culprit lesions were performed using Virtual Histology software. Plaque burden was described based on fibrotic, fibro-fatty, dense calcium, and necrotic core (NC) components, and thin-cap fibroatheroma (TCFA) was defined as focal NC rich (> 10%) plaques touching the lumen with a percent-plaque volume exceeding 40%.
  
  
  RESULTS
  Averaged %FMD was 2.86 ± 2.03% (median 2.27%, 25th 1.40%, 75th 4.20%). NC volumes were negatively correlated with log%FMD for both culprit and non-culprit lesions (P = 0.001, r = 0.31 and P = 0.03, r = 0.21, respectively). We divided the patients into three tertiles according to %FMD; 38 were lower (≤ 1.75%), 41 were middle (> 1.75%, but ≤ 3.5%), and 32 were upper tertile (> 3.5%). The prevalence rate of TCFA increased with decreasing %FMD tertile and the incidence of major adverse cardiac events was significantly higher in lower %FMD tertile. Multivariate logistic regression analyses showed that the most powerful predictive factor for TCFA was log%FMD (P < 0.0001), and ROC curve analysis identified %FMD of < 2.81% (AUC = 0.82, sensitivity: 91.2%, specificity: 66.7%) as the optimal cut-off point for predicting the presence of TCFA.
  
  
  CONCLUSIONS
  Impaired endothelial function in brachial arteries may be associated with whole coronary plaque vulnerability and poor clinical outcome in patients with CAD.
authors.affiliation: Hyogo Prefectural Awaji Hospital, Division of Cardiovascular Medicine, Department of Internal Medicine, Japan. taktak319@yahoo.co.jp
authors.forename: Takahiro
authors.initials: T
authors.lastname: Sawada
authors.forename: Takuo
authors.initials: T
authors.lastname: Emoto
authors.forename: Yoshiki
authors.initials: Y
authors.lastname: Motoji
authors.forename: Megumi
authors.initials: M
authors.lastname: Hashimoto
authors.forename: Hiroko
authors.initials: H
authors.lastname: Kageyama
authors.forename: Daisuke
authors.initials: D
authors.lastname: Terashita
authors.forename: Taiji
authors.initials: T
authors.lastname: Mizoguchi
authors.forename: Takao
authors.initials: T
authors.lastname: Mizuguchi
authors.forename: Masamichi
authors.initials: M
authors.lastname: Iwasaki
authors.forename: Kazuki
authors.initials: K
authors.lastname: Taira
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Okamoto
authors.forename: Yosuke
authors.initials: Y
authors.lastname: Matsuo
authors.forename: Sushi-ku
authors.initials: SK
authors.lastname: Kim
authors.forename: Akira
authors.initials: A
authors.lastname: Takarada
authors.forename: Mitsuhiro
authors.initials: M
authors.lastname: Yokoyama
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001783:Blood Flow Velocity / Q000502:physiology*; D001916:Brachial Artery / Q000000981:diagnostic imaging* / Q000502:physiology*; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging* / Q000453:epidemiology / Q000503:physiopathology; D003430:Cross-Sectional Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D058226:Plaque, Atherosclerotic / Q000000981:diagnostic imaging* / Q000453:epidemiology / Q000503:physiopathology; D011859:Radiography; D014664:Vasodilation / Q000502:physiology*