Underestimation of extent of ischemia by gated SPECT myocardial perfusion imaging in patients with left main coronary artery disease.
BACKGROUND
There have been limited data regarding the value of gated single photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) for the detection of left main coronary artery disease (CAD).


RESULTS
We studied 101 patients with angiographic left main CAD (> or = 50% stenosis) and no prior myocardial infarction or coronary revascularization who underwent gated exercise or adenosine stress technetium 99m sestamibi SPECT MPI. By perfusion assessment alone, high-risk disease with moderate to severe defects (> 10% myocardium at stress) was identified in only 56% of patients visually and 59% quantitatively. Absence of significant perfusion defect (> or = 5% myocardium) was seen in 13% of patients visually and 15% quantitatively. However, by combining visual perfusion data and nonperfusion variables, especially transient ischemic dilation, 83% of patients were identified as high risk.


CONCLUSIONS
The findings of this study demonstrate that assessment of perfusion data alone by visual or quantitative SPECT MPI analysis underestimates the magnitude of left main CAD. The combination of perfusion and nonperfusion abnormalities on gated MPI identifies high risk in most patients with left main CAD.
Department of Imaging (Division of Nuclear Medicine), Cedars-Sinai Medical Center, Los Angeles, Calif 90048, USA. bermand@cshs.org
Daniel S
DS
Berman
Xingping
X
Kang
Piotr J
PJ
Slomka
James
J
Gerlach
Ling
L
de Yang
Sean W
SW
Hayes
John D
JD
Friedman
Louise E J
LE
Thomson
Guido
G
Germano
D000368:Aged; D000792:Angiography / Q000379:methods; D017023:Coronary Angiography; D003324:Coronary Artery Disease / Q000175:diagnosis* / Q000473:pathology*; D005260:Female; D006321:Heart / Q000000981:diagnostic imaging; D006801:Humans; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000175:diagnosis* / Q000473:pathology*; D010477:Perfusion; D019275:Radiopharmaceuticals / Q000494:pharmacology; D017256:Technetium Tc 99m Sestamibi / Q000494:pharmacology; D015899:Tomography, Emission-Computed, Single-Photon / Q000295:instrumentation / Q000379:methods*
D019275:Radiopharmaceuticals; D017256:Technetium Tc 99m Sestamibi