title: Assessment of intermediate stenosis in the left anterior descending coronary artery with contrast-enhanced transthoracic Doppler echocardiography.
abstract: BACKGROUND
  Visual or quantitative assessment of coronary angiography may not exactly predict the physiological significance of intermediate (40-70%) coronary stenosis. Coronary flow reserve is a well-established marker of the functional significance of coronary stenosis.
  
  
  OBJECTIVE
  The aim of this study was to compare the coronary flow velocity reserve (CFVR) using contrast-enhanced transthoracic Doppler echocardiography (CE-TTDE) with thallium-201 imaging in assessment of intermediate lesions in the left anterior descending coronary artery (LAD).
  
  
  METHODS
  A consecutive series of 50 patients with intermediate stenosis in the LAD underwent pharmacological stress thallium-201 imaging and CFVR measured by CE-TTDE.
  
  
  RESULTS
  CFVR could be measured in 49 of 50 patients by the present method. A CFVR <2.0 predicted the presence of a stress thallium defect in 12 of 14 patients (agreement=90%, kappa=0.76, P < 0.001). The sensitivity and specificity of CFVR for stress thallium-201 results were 86 and 91%, respectively. In contrast, significant stenosis (>50% by diameter) showed fair agreement for stress thallium defects (agreement=59%, kappa=0.28, P < 0.05).
  
  
  CONCLUSIONS
  In the evaluation of intermediate lesions in the LAD, CFVR as assessed by CE-TTDE could accurately predict the presence of ischemia on stress thallium imaging, whereas angiographic stenosis did not yield reliable results.
authors.affiliation: Department of Carediology, Kitaishikai Hospital, 2632-3 Tokunomori, Ozu, Ehime 795-0061, Japan. hiokayam@sea.plala.or.jp
authors.forename: Hideki
authors.initials: H
authors.lastname: Okayama
authors.forename: Takumi
authors.initials: T
authors.lastname: Sumimoto
authors.forename: Go
authors.initials: G
authors.lastname: Hiasa
authors.forename: Kazuhisa
authors.initials: K
authors.lastname: Nishimura
authors.forename: Norikatsu
authors.initials: N
authors.lastname: Morioka
authors.forename: Kouzo
authors.initials: K
authors.lastname: Yamamoto
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Kawada
mesh_terms: D000255:Adenosine Triphosphate; D000368:Aged; D001158:Arteries / Q000000981:diagnostic imaging / Q000503:physiopathology; D001783:Blood Flow Velocity / Q000502:physiology; D017023:Coronary Angiography; D003326:Coronary Circulation / Q000502:physiology; D023921:Coronary Stenosis / Q000175:diagnosis* / Q000453:epidemiology / Q000503:physiopathology; D003331:Coronary Vessels / Q000000981:diagnostic imaging / Q000503:physiopathology; D004452:Echocardiography; D015150:Echocardiography, Doppler / Q000379:methods; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007089:Image Enhancement; D007262:Infusions, Intravenous; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D013794:Thallium Radioisotopes; D015899:Tomography, Emission-Computed, Single-Photon
chemical_list: D013794:Thallium Radioisotopes; D000255:Adenosine Triphosphate