title: Assessment of contractile response to dobutamine stress by means of ECG-gated myocardial SPECT: comparison with myocardial perfusion and fatty acid metabolism.
abstract: The present study assessed left ventricular performance during dobutamine stress measured using gated SPECT, and compared the results to myocardial perfusion and fatty acid metabolism.
  
  
  METHODS
  Thirty-six patients with myocardial infarction given (99m)Tc-sestamibi or (99m)Tc-tetrofosmin were examined by gated SPECT at rest and during dobutamine stress (4-20 microg x kg(-1) x min(-1)). After acquiring data at the highest dose, 201TlCl was injected and dual-isotope SPECT was performed to assess myocardial ischemia. Thirty of 36 patients also underwent myocardial SPECT with 123I-BMIPP. Regional wall motion changes during dobutamine infusion were determined from the gated SPECT data and classified as: (1) Improvement, (2) Worsening, (3) No change, and (4) Biphasic response. For myocardial segments of each infarct area, stress 201Tl, rest (99m)Tc and (123)I-BMIPP uptakes were graded on a five-point scoring system of defects from 0 (normal) to 4 (grossly defective).
  
  
  RESULTS
  Rest 99mTc defect score index (DSI) in No change area was significantly higher than that in Biphasic area. The ADSI (stress 201Tl - rest (99m)Tc) in Biphasic area was significantly higher than those in Improvement and No change areas. The deltaDSI (BMIPP - (99m)Tc) in Worsening area tended to be higher than that in No Change area.
  
  
  CONCLUSIONS
  Regional contractile response to dobutamine stress analyzed by gated SPECT showed that the response in-myocardial infarct areas could be classified by rest and stress myocardial perfusion and BMIPP accumulation.
authors.affiliation: Department of Radiology, Nippon Medical School, 1-1-5 Sendagi, Bunkyoku, Tokyo 113-8603, Japan. s-kumita@nms.ac.jp
authors.forename: Shin-ichiro
authors.initials: S
authors.lastname: Kumita
authors.forename: Keiichi
authors.initials: K
authors.lastname: Cho
authors.forename: Hidenobu
authors.initials: H
authors.lastname: Nakajo
authors.forename: Masahiro
authors.initials: M
authors.lastname: Toba
authors.forename: Yoshimitsu
authors.initials: Y
authors.lastname: Fukushima
authors.forename: Sunao
authors.initials: S
authors.lastname: Mizumura
authors.forename: Junko
authors.initials: J
authors.lastname: Sano
authors.forename: Teruo
authors.initials: T
authors.lastname: Takano
authors.forename: Tatsuo
authors.initials: T
authors.lastname: Kumazaki
mesh_terms: D003331:Coronary Vessels / Q000000981:diagnostic imaging*; D004280:Dobutamine; D004562:Electrocardiography; D005080:Exercise Test / Q000379:methods; D005227:Fatty Acids / Q000097:blood*; D005260:Female; D015637:Gated Blood-Pool Imaging / Q000379:methods*; D006801:Humans; D008875:Middle Aged; D009200:Myocardial Contraction; D009203:Myocardial Infarction / Q000150:complications / Q000000981:diagnostic imaging* / Q000378:metabolism*; D013223:Statistics as Topic; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods; D018487:Ventricular Dysfunction, Left / Q000000981:diagnostic imaging* / Q000209:etiology / Q000378:metabolism*
chemical_list: D005227:Fatty Acids; D004280:Dobutamine