title: Usefulness of electron beam computed tomography for quantitative estimation of myocardial ischemia in patients.
abstract: BACKGROUND
  The electron beam computed tomography (EBT) was used as non-invasive methods for estimating mycardial characteristics in patients after onset of Kawasaki disease.
  
  
  METHODS
  All of the 22 coronary branches with localized stenosis (LS), and 22 branches without coronary artery lesion after Kawasaki disease were examined for changes of myocardial CT number. In this study, each myocardial region was divided into three parts (endocardial, central, epicardial parts) and the myocardium/lumen (M/L) ratio was calculated.
  
  
  RESULTS
  The mean M/L ratio in the endocardial part of early image with LS was significantly lower than the ratios in the other parts of early images with LS (P = 0.0286, P = 0.0069, respectively). and only the mean M/L ratio in the endocardial part was significantly different on images from patients with LS and images from patients without LS (P = 0.0296). Inverse correlations were found in the LS group between coronary artery stenosis rate determined by coronary angiography and M/L ratio in the endocardial part on early images (P = 0.0018, r = -0.614, y = 0.56 -0.605x).
  
  
  CONCLUSIONS
  It was possible to quantitatively evalutate myocardial characteristics using EBT. It is suggested that myocardial ischemia progressed from the endocardial region and EBT is useful to detect the endocardial ischemia. We suggested that the rate of coronary stenosis in patients with LS can be estimated by calculating the M/L rations in the endocardial parts of early EBT images. EBT enables accurate evaluation of myocardial characteristics non-invasively.
authors.affiliation: Department of Pediatrics, National Cardiovascular Center, Osaka University Medical School, Osaka, Japan. hikoendoh@yahoo.co.jp
authors.forename: Hikosato
authors.initials: H
authors.lastname: Endoh
authors.forename: Shinya
authors.initials: S
authors.lastname: Tsukano
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Ishikawa
authors.forename: Motoki
authors.initials: M
authors.lastname: Takamuro
authors.forename: Etsuko
authors.initials: E
authors.lastname: Tsuda
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Ono
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Arakaki
authors.forename: Shigeyuki
authors.initials: S
authors.lastname: Echigo
authors.forename: Ryoichi
authors.initials: R
authors.lastname: Tanaka
authors.forename: Makoto
authors.initials: M
authors.lastname: Takamiya
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Naito
mesh_terms: D000293:Adolescent; D000328:Adult; D016022:Case-Control Studies; D002648:Child; D017023:Coronary Angiography; D023921:Coronary Stenosis / Q000000981:diagnostic imaging* / Q000209:etiology; D018450:Disease Progression; D005260:Female; D006801:Humans; D008297:Male; D009080:Mucocutaneous Lymph Node Syndrome / Q000150:complications / Q000000981:diagnostic imaging*; D017202:Myocardial Ischemia / Q000000981:diagnostic imaging* / Q000209:etiology; D011336:Probability; D011379:Prognosis; D011856:Radiographic Image Enhancement; D012016:Reference Values; D018570:Risk Assessment; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D014057:Tomography, X-Ray Computed / Q000379:methods*; D014654:Vascular Patency / Q000502:physiology; D014655:Vascular Resistance / Q000502:physiology