title: Reduction of coronary flow reserve in areas with and without ischemia on stress perfusion imaging in patients with coronary artery disease: a study using oxygen 15-labeled water PET.
abstract: BACKGROUND
  Myocardial perfusion single photon emission computed tomography (SPECT) occasionally fails to detect coronary stenosis in patients with coronary artery disease (CAD). We evaluated coronary flow reserve (CFR) using oxygen 15-labeled water in areas with and without ischemia on technetium 99m tetrofosmin stress perfusion SPECT in patients with angiographically documented CAD.
  
  
  RESULTS
  Twenty-seven patients with CAD and eleven age-matched normal subjects were studied. Baseline myocardial blood flow (MBF) and MBF during hyperemia induced by intravenous adenosine triphosphate infusion (0.16 mg. kg(-1). min(-1)) were determined with the use of O-15-labeled water positron emission tomography, and the CFR was calculated. Tc-99m tetrofosmin stress/rest SPECT was performed for comparison. On the basis of the results of coronary angiography and SPECT, coronary segments were divided into 3 types: segments with coronary stenosis and a perfusion abnormality on stress SPECT imaging (group A, n = 16), segments with coronary stenosis without a perfusion abnormality (group B, n = 42), and remote segments with no coronary stenosis or perfusion abnormality (group C, n = 18). Baseline MBF values were similar among the 3 groups. CFR in group A was lower (1.82 +/- 0.54) than in group B (2.22 +/- 0.87, P <.05), in group C (2.92 +/- 1.21, P <.01), and in normal segments (3.86 +/- 1.24, P <.001). CFR in group B was lower than in group C (P <.02) and in normal segments (P <.001). CFR in group C was lower than in normal segments (P <.02).
  
  
  CONCLUSIONS
  Areas with a perfusion abnormality on stress SPECT had reduced CFR. In the areas without a perfusion abnormality and with coronary stenosis, lowering of CFR was intermediate between the areas with a perfusion abnormality and remote segments. Moreover, CFR was slightly, but significantly, lower in remote segments in patients with CAD compared with normal segments.
authors.affiliation: Department of Nuclear Medicine, Hokkaido University Graduate School of Medicine, Sapporo, Japan.
authors.forename: Keiichiro
authors.initials: K
authors.lastname: Yoshinaga
authors.forename: Chietsugu
authors.initials: C
authors.lastname: Katoh
authors.forename: Kazuyuki
authors.initials: K
authors.lastname: Noriyasu
authors.forename: Yasuyoshi
authors.initials: Y
authors.lastname: Iwado
authors.forename: Hideto
authors.initials: H
authors.lastname: Furuyama
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Ito
authors.forename: Yuji
authors.initials: Y
authors.lastname: Kuge
authors.forename: Tetsuro
authors.initials: T
authors.lastname: Kohya
authors.forename: Akira
authors.initials: A
authors.lastname: Kitabatake
authors.forename: Nagara
authors.initials: N
authors.lastname: Tamaki
mesh_terms: D000368:Aged; D001794:Blood Pressure / Q000502:physiology; D017023:Coronary Angiography; D003326:Coronary Circulation / Q000502:physiology*; D023921:Coronary Stenosis / Q000175:diagnosis / Q000503:physiopathology*; D005080:Exercise Test; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009943:Organophosphorus Compounds; D015609:Organotechnetium Compounds; D010104:Oxygen Radioisotopes; D019275:Radiopharmaceuticals; D014055:Tomography, Emission-Computed; D015899:Tomography, Emission-Computed, Single-Photon
chemical_list: D009943:Organophosphorus Compounds; D015609:Organotechnetium Compounds; D010104:Oxygen Radioisotopes; D019275:Radiopharmaceuticals; C078700:technetium tc-99m tetrofosmin