title: Value of attenuation correction on ECG-gated SPECT myocardial perfusion imaging related to body mass index.
abstract: BACKGROUND
  Obesity is a growing problem in the United States, and attenuation artifacts are more prevalent in this patient group. This study evaluated the impact of attenuation correction in patients with a high body mass index (BMI).
  
  
  RESULTS
  Three readers interpreted gated attenuation-corrected and non-attenuation-corrected rest/stress technetium 99m sestamibi myocardial perfusion imaging results in 116 patients (BMI <30, n = 60; BMI > or =30, n = 56) who had coronary angiography no more than 60 days after imaging. Readers were blinded to all clinical information and as to whether myocardial perfusion imaging was attenuation-corrected or non-attenuation-corrected. Sensitivity, specificity, and accuracy for detection of coronary artery disease of 70% or greater for attenuation-corrected versus non-attenuation-corrected single photon emission computed tomography (SPECT) were 86% versus 89%, 79% versus 50%, and 84% versus 79%, respectively. Sensitivity, specificity, and accuracy for attenuation-corrected versus non-attenuation-corrected SPECT for patients with BMI less than 30 were 90% versus 90%, 82% versus 64%, and 88% versus 85%, respectively. For BMI of 30 or greater, the results were 82% versus 87%, 76% versus 41%, and 80% versus 73%, respectively. There was a significant difference in specificity overall ( P = .02) and for the category of BMI of 30 or greater ( P = .03).
  
  
  CONCLUSIONS
  This study demonstrates that electrocardiography-gated attenuation-corrected Tc-99m sestamibi SPECT myocardial perfusion imaging improves specificity compared with electrocardiography-gated non-attenuation-corrected SPECT myocardial perfusion imaging, especially in patients with BMI of 30 or greater.
authors.affiliation: Mid-America Heart Institute and Cardiovascular Consultants, 4330 Wornall Street, Kansas City, MO 64111, USA. rthompson@cc-pc.com
authors.forename: Randall C
authors.initials: RC
authors.lastname: Thompson
authors.forename: Gary V
authors.initials: GV
authors.lastname: Heller
authors.forename: Lynne L
authors.initials: LL
authors.lastname: Johnson
authors.forename: James A
authors.initials: JA
authors.lastname: Case
authors.forename: S James
authors.initials: SJ
authors.lastname: Cullom
authors.forename: Ernest V
authors.initials: EV
authors.lastname: Garcia
authors.forename: Philip G
authors.initials: PG
authors.lastname: Jones
authors.forename: Kelly L
authors.initials: KL
authors.lastname: Moutray
authors.forename: Timothy M
authors.initials: TM
authors.lastname: Bateman
mesh_terms: D016477:Artifacts; D015992:Body Mass Index; D003324:Coronary Artery Disease / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D004562:Electrocardiography / Q000379:methods; D005260:Female; D015637:Gated Blood-Pool Imaging / Q000379:methods*; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D016037:Single-Blind Method; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*