title: Assessment of carotid plaque neovascularization using quantitative analysis of contrast-enhanced ultrasound imaging is useful for risk stratification in patients with coronary artery disease.
abstract: BACKGROUND
  Contrast-enhanced ultrasound (CEUS) of the carotid artery is a potential technique for imaging plaque neovascularization, a feature of unstable atherosclerotic plaques. This study examined whether assessment of intra-plaque neovascularization of the carotid artery using CEUS provides prognostic information in patients with coronary artery disease (CAD).
  
  
  METHODS
  A total of 206 patients with stable CAD underwent a CEUS examination of the carotid artery and were followed up prospectively for <38 months or until a cardiac event (cardiac death, non-fatal myocardial infarction (MI), unstable angina pectoris (uAP) requiring unplanned coronary revascularization, or heart failure requiring hospitalization). The degree of contrast signals measured within the carotid plaque was quantified by calculating the mean gray scale level within the region of interest of the carotid plaque, expressed as plaque enhanced intensity.
  
  
  RESULTS
  During the follow-up period, 31 events occurred (2 cardiac deaths, 7 non-fatal MIs, 16 uAP, and 6 heart failure). Multivariate Cox proportional hazard analysis showed that plaque enhanced intensity was a significant predictor of cardiac events independent of traditional risk factors (HR, 1.13; 95% CI, 1.05-1.21; p<0.001). The addition of the plaque enhanced intensity to traditional risk factors resulted in net reclassification improvement (NRI) and integrated discrimination improvement (IDI) (NRI 0.62, p=0.001; and IDI 0.106, p=0.002).
  
  
  CONCLUSIONS
  The assessment of carotid plaque neovascularization using quantitative analysis of CEUS may be useful for risk stratification in patients with CAD.
authors.affiliation: Department of Internal Medicine II, University of Yamanashi, Faculty of Medicine, Chuo, Yamanashi, Japan.
authors.forename: Jun
authors.initials: J
authors.lastname: Nakamura
authors.affiliation: Department of Internal Medicine II, University of Yamanashi, Faculty of Medicine, Chuo, Yamanashi, Japan.
authors.forename: Takamitsu
authors.initials: T
authors.lastname: Nakamura
authors.affiliation: Department of Internal Medicine II, University of Yamanashi, Faculty of Medicine, Chuo, Yamanashi, Japan.
authors.forename: Juntaro
authors.initials: J
authors.lastname: Deyama
authors.affiliation: Department of Internal Medicine II, University of Yamanashi, Faculty of Medicine, Chuo, Yamanashi, Japan.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Fujioka
authors.affiliation: Department of Internal Medicine II, University of Yamanashi, Faculty of Medicine, Chuo, Yamanashi, Japan.
authors.forename: Ken-ichi
authors.initials: K
authors.lastname: Kawabata
authors.affiliation: Department of Internal Medicine II, University of Yamanashi, Faculty of Medicine, Chuo, Yamanashi, Japan.
authors.forename: Jun-ei
authors.initials: JE
authors.lastname: Obata
authors.affiliation: Department of Internal Medicine II, University of Yamanashi, Faculty of Medicine, Chuo, Yamanashi, Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Watanabe
authors.affiliation: Department of Internal Medicine II, University of Yamanashi, Faculty of Medicine, Chuo, Yamanashi, Japan.
authors.forename: Yosuke
authors.initials: Y
authors.lastname: Watanabe
authors.affiliation: Department of Internal Medicine II, University of Yamanashi, Faculty of Medicine, Chuo, Yamanashi, Japan. Electronic address: kugiyama@yamanashi.ac.jp.
authors.forename: Kiyotaka
authors.initials: K
authors.lastname: Kugiyama
mesh_terms: D000368:Aged; D002339:Carotid Arteries / Q000000981:diagnostic imaging / Q000473:pathology; D003324:Coronary Artery Disease / Q000175:diagnosis*; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007564:Japan; D008297:Male; D008875:Middle Aged; D009389:Neovascularization, Pathologic / Q000000981:diagnostic imaging*; D058226:Plaque, Atherosclerotic / Q000000981:diagnostic imaging / Q000473:pathology; D011237:Predictive Value of Tests; D011379:Prognosis; D016016:Proportional Hazards Models; D011446:Prospective Studies; D018570:Risk Assessment; D014463:Ultrasonography / Q000379:methods
keywords: Carotid artery; Contrast-enhanced ultrasound; Coronary artery disease; Neovascularization; Prognosis