Functionally relevant coronary artery disease: comparison of 64-section CT angiography with myocardial perfusion SPECT.
OBJECTIVE
To prospectively determine the accuracy of 64-section computed tomographic (CT) angiography for the depiction of coronary artery disease (CAD) that induces perfusion defects at myocardial perfusion imaging with single photon emission computed tomography (SPECT), by using myocardial perfusion imaging as the reference standard.


METHODS
All patients gave written informed consent after the study details, including radiation exposure, were explained. The study protocol was approved by the local institutional review board. In patients referred for elective conventional coronary angiography, an additional 64-section CT angiography study and a myocardial perfusion imaging study (1-day adenosine stress-rest protocol) with technetium 99m-tetrofosmin SPECT were performed before conventional angiography. Coronary artery diameter narrowing of 50% or greater at CT angiography was defined as stenosis and was compared with the myocardial perfusion imaging findings. Quantitative coronary angiography served as a reference standard for CT angiography.


RESULTS
A total of 1093 coronary segments in 310 coronary arteries in 78 patients (mean age, 65 years +/- 9 [standard deviation]; 35 women) were analyzed. CT angiography revealed stenoses in 137 segments (13%) corresponding to 91 arteries (29%) in 46 patients (59%). SPECT revealed 14 reversible, 13 fixed, and six partially reversible defects in 31 patients (40%). Sensitivity, specificity, and negative and positive predictive values, respectively, of CT angiography in the detection of reversible myocardial perfusion imaging defects were 95%, 53%, 94%, and 58% on a per-patient basis and 95%, 75%, 96%, and 72% on a per-artery basis. Agreement between CT and conventional angiography was very good (96% and kappa = 0.92 for patient-based analysis, 93% and kappa = 0.84 for vessel-based analysis).


CONCLUSIONS
Sixty-four-section CT angiography can help rule out hemodynamically relevant CAD in patients with intermediate to high pretest likelihood, although an abnormal CT angiography study is a poor predictor of ischemia.
Gaemperli
Oliver
O
Cardiovascular Center, University Hospital Zurich, Ramistrasse 100, NUK C 32, CH-8091 Zurich, Switzerland.
Schepis
Tiziano
T
Valenta
Ines
I
Koepfli
Pascal
P
Husmann
Lars
L
Scheffel
Hans
H
Leschka
Sebastian
S
Eberli
Franz R
FR
Luscher
Thomas F
TF
Alkadhi
Hatem
H
Kaufmann
Philipp A
PA
D000368:Aged; D016009:Chi-Square Distribution; D017023:Coronary Angiography / Q000379:methods*; D003327:Coronary Disease / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D009943:Organophosphorus Compounds; D015609:Organotechnetium Compounds; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012372:ROC Curve; D019275:Radiopharmaceuticals; D012680:Sensitivity and Specificity; D015899:Tomography, Emission-Computed, Single-Photon; D014057:Tomography, X-Ray Computed
D009943:Organophosphorus Compounds; D015609:Organotechnetium Compounds; D019275:Radiopharmaceuticals; C078700:technetium tc-99m tetrofosmin