title: Incremental value of parametric quantitative assessment of myocardial perfusion by triggered Low-Power myocardial contrast echocardiography.
abstract: OBJECTIVE
  The purpose of this study was to compare the assessment of myocardial perfusion by myocardial parametric quantification (MPQ) with technetium-99m sestamibi single-photon emission computed tomographic (SPECT) imaging in humans.
  
  
  BACKGROUND
  Accurate visual interpretation of myocardial contrast echocardiographic (MCE) images is qualitative and requires considerable experience. Current computer-assisted quantitative perfusion protocols are tedious and lack spatial resolution. Myocardial parametric quantification is a novel method that quantifies, color encodes, and displays perfusion data as a set of myocardial parametric images according to the relative degree of perfusion.
  
  
  METHODS
  Forty-six consecutive patients underwent prospective stress/rest technetium-99m sestamibi gated-SPECT imaging and MCE using intravenous Optison or Definity. Apical two- and four-chamber cine loops at rest and after dipyridamole (0.56 mg/kg) stress were acquired. For each patient, the following assessments of myocardial perfusion were performed: 1). visual cine-loop assessment (VIS); 2). MPQ assessment; and 3). combined VIS + MPQ assessment.
  
  
  RESULTS
  The segmental rates of agreement for myocardial perfusion with SPECT were 83%, 89%, and 92% (kappa = 0.46, 0.58, and 0.68) for VIS, MPQ, and VIS + MPQ, respectively. Similar trends were seen for the classification of the presence or absence of a moderate to severe perfusion defect, with the agreement for VIS, MPQ, and VIS + MPQ being 92%, 97%, and 97%, respectively.
  
  
  CONCLUSIONS
  Myocardial parametric quantification demonstrates good agreement with SPECT and incremental agreement with VIS. Analysis strategies that incorporate MPQ demonstrate better agreement with SPECT than visual analysis alone.
authors.affiliation: Gordon Yu Hoi Chiu Echocardiographic Laboratory, The Toronto Western Hospital, Toronto, Canada. eric.yu@uhn.on.ca
authors.forename: Eric H C
authors.initials: EH
authors.lastname: Yu
authors.forename: Danny M
authors.initials: DM
authors.lastname: Skyba
authors.forename: Howard
authors.initials: H
authors.lastname: Leong-Poi
authors.forename: Cairrine
authors.initials: C
authors.lastname: Sloggett
authors.forename: Michal
authors.initials: M
authors.lastname: Jamorski
authors.forename: Rohit
authors.initials: R
authors.lastname: Garg
authors.forename: R Mark
authors.initials: RM
authors.lastname: Iwanochko
authors.forename: Samuel C
authors.initials: SC
authors.lastname: Siu
mesh_terms: D000328:Adult; D000368:Aged; D000418:Albumins; D003287:Contrast Media / Q000494:pharmacology; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging*; D003326:Coronary Circulation; D004452:Echocardiography / Q000379:methods*; D005080:Exercise Test / Q000379:methods; D005260:Female; D005466:Fluorocarbons; D006801:Humans; D008297:Male; D008875:Middle Aged; D019275:Radiopharmaceuticals; D017256:Technetium Tc 99m Sestamibi; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*
chemical_list: D000418:Albumins; D003287:Contrast Media; C099458:FS 069; D005466:Fluorocarbons; D019275:Radiopharmaceuticals; D017256:Technetium Tc 99m Sestamibi; C042852:perflutren