title: Poststress measurements of left ventricular function with gated perfusion SPECT: comparison with resting measurements by using a same-day perfusion-function protocol.
abstract: OBJECTIVE
  To investigate the relationship between the development of ischemia during stress testing and the changes in left ventricular ejection fraction (LVEF) measurements obtained after stress and at rest with a same-day perfusion-function imaging protocol.
  
  
  METHODS
  One hundred twenty-six patients underwent a same-day rest-stress (61%) or stress-rest (39%) protocol and gated single photon emission computed tomography (SPECT). Perfusion analysis was performed with a 12-segment model. Defects were scored (0 = no defect, 1 = mild defect, 2 = moderate defect, and 3 = severe defect); differences between the summed stress and resting scores of greater than three indicated substantial ischemia.
  
  
  RESULTS
  Resting and poststress LVEFs correlated significantly (r = 0.97, P <.001); however, patients with and patients without ischemia had significant differences in poststress versus resting LVEFs (-4.0 vs 1.0, respectively; P <.01). In patients with ischemia versus patients without ischemia, subgroup analysis stress-rest (-2.5 vs 1.0, P =.047) and rest-stress (-4.0 vs 1.0, P =.006) protocols yielded similar results.
  
  
  CONCLUSIONS
  In patients with clinically important stress-induced perfusion abnormalities, the LVEF after stress was significantly lower than the LVEF at rest with same-day rest-stress and stress-rest imaging protocols. In the clinical setting, poststress LVEFs may be lower than true resting measurements, particularly in patients with moderate to severe stress-induced ischemia.
authors.affiliation: Departments of Radiology-Nuclear Medicine, Duke University Medical Center and Health Systems, Duke North Rm 1410, Durham, NC 27710, USA. borge001@mc.duke.edu
authors.forename: S
authors.initials: S
authors.lastname: Borges-Neto
authors.forename: A
authors.initials: A
authors.lastname: Javaid
authors.forename: L K
authors.initials: LK
authors.lastname: Shaw
authors.forename: D F
authors.initials: DF
authors.lastname: Kong
authors.forename: M W
authors.initials: MW
authors.lastname: Hanson
authors.forename: R A
authors.initials: RA
authors.lastname: Pagnanelli
authors.forename: G
authors.initials: G
authors.lastname: Ravizzini
authors.forename: R E
authors.initials: RE
authors.lastname: Coleman
mesh_terms: D000241:Adenosine; D000318:Adrenergic beta-Agonists; D000368:Aged; D003326:Coronary Circulation / Q000502:physiology; D003327:Coronary Disease / Q000503:physiopathology; D004176:Dipyridamole; D004280:Dobutamine; D005080:Exercise Test; D005260:Female; D005500:Follow-Up Studies; D006321:Heart / Q000000981:diagnostic imaging*; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000209:etiology / Q000503:physiopathology; D005082:Physical Exertion / Q000502:physiology*; D011237:Predictive Value of Tests; D019275:Radiopharmaceuticals; D012146:Rest / Q000502:physiology; D016037:Single-Blind Method; D013318:Stroke Volume / Q000502:physiology*; D017256:Technetium Tc 99m Sestamibi; D015899:Tomography, Emission-Computed, Single-Photon; D014665:Vasodilator Agents; D016277:Ventricular Function, Left / Q000502:physiology*
chemical_list: D000318:Adrenergic beta-Agonists; D019275:Radiopharmaceuticals; D014665:Vasodilator Agents; D004280:Dobutamine; D004176:Dipyridamole; D017256:Technetium Tc 99m Sestamibi; D000241:Adenosine