Resting cardiac 64-MDCT does not reliably detect myocardial ischemia identified by radionuclide imaging.
OBJECTIVE
CT myocardial perfusion imaging is an emerging diagnostic modality that is under intensive study but not yet widely used in clinical practice. The purpose of this study is to evaluate the performance of resting 64-MDCT in revealing ischemia identified on radionuclide myocardial perfusion imaging (MPI).


METHODS
We retrospectively identified 35 patients (20 women and 15 men; mean age, 52 years) with myocardial ischemia found on MPI who underwent retrospectively gated CT within 90 days of MPI. Myocardial perfusion on CT was evaluated using both a visual (n = 35) and an automated (n = 34) method. For the visual method, myocardial segments were evaluated qualitatively in systole and diastole. For the automated method, subendocardial perfusion of the standard 17 American Heart Association segments was measured using a commercially available tool in both systole and diastole. Differences between systolic and diastolic perfusion were computed.


RESULTS
Five hundred eighty myocardial segments were evaluated, 152 of which were ischemic on MPI. Visual analysis had a sensitivity of 16% (24/152), specificity of 92% (393/428), positive predictive value of 40% (24/60), and negative predictive value of 75% (392/520) in systole, and a sensitivity of 18% (27/152), specificity of 89% (382/428), positive predictive value of 37% (27/73), and negative predictive value of 75% (382/507) in diastole, as compared with MPI. There was no significant difference in subendocardial perfusion between ischemic and nonischemic segments by the automated method. There was no significant difference in CT perfusion between patients with and without obstructive coronary artery disease on CT angiography using the visual or automated methods.


CONCLUSIONS
Resting 64-MDCT is unsuitable for clinical use in revealing ischemia seen on MPI.
Department of Radiology, Albert Einstein College of Medicine, Montefiore Medical Center, 111 East 210th St, Bronx, NY 10467-2490, USA.
Ari J
AJ
Spiro
Linda B
LB
Haramati
Vineet R
VR
Jain
Alla
A
Godelman
Mark I
MI
Travin
Jeffrey M
JM
Levsky
D000293:Adolescent; D000328:Adult; D000368:Aged; D055424:Cardiac-Gated Imaging Techniques / Q000379:methods; D003287:Contrast Media; D017023:Coronary Angiography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D017202:Myocardial Ischemia / Q000000981:diagnostic imaging*; D049268:Positron-Emission Tomography / Q000379:methods*; D011237:Predictive Value of Tests; D011857:Radiographic Image Interpretation, Computer-Assisted; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D018709:Statistics, Nonparametric; D014057:Tomography, X-Ray Computed / Q000379:methods*; D014283:Triiodobenzoic Acids
D003287:Contrast Media; D014283:Triiodobenzoic Acids; C044834:iodixanol