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).
Methods and 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.