Significant coronary artery stenosis: comparison on per-patient and per-vessel or per-segment basis at 64-section CT angiography.
OBJECTIVE
To prospectively evaluate the accuracy of 64-section computed tomographic (CT) coronary angiography for assessing significant stenosis on a global and segmental level, by using conventional coronary artery angiography as the reference standard.


METHODS
This study was HIPAA compliant and had local institutional review board approval. Patients gave informed consent. Patients suspected of having coronary artery disease (CAD) underwent both conventional coronary catheter angiography and contrast material-enhanced retrospectively electrocardiographically gated 64-section multi-detector row CT of the coronary arteries. Two experienced observers analyzed all CT scans for signs of CAD (stenosis of 0%, <or=49%, 50%-69%, 70%-99%, or 100%). Diagnostic accuracy of CT coronary angiography compared with that of conventional angiography was determined on a per-segment, per-vessel, and per-patient basis. No patients, vessels, or segments were excluded from analysis. Spearman correlation, cross tables, and a chi(2) test were used for statistical analysis.


RESULTS
On a per-segment basis, 92.4% (762 of 825) of all segments could be clearly evaluated. In 7.6% of segments, image quality was compromised either by misregistration (16%), motion artifacts (30%), or small vessel size (54%). Correlation coefficients for detection and grading of stenosis were r=0.65 on a per-segment, r=0.83 on a per-vessel, and r=0.88 on a per-patient basis. Stenoses of 50% or greater were detected with accuracy, sensitivity, and specificity, respectively, of 96.1% (793 of 825), 82% (50 of 61), and 97.1% (743 of 765) on a per-segment basis, 90.9% (150 of 165), 89% (32 of 36), and 91.5% (118 of 129) on a per-vessel basis, and 89% (49 of 55), 100% (19 of 19), and 83% (30 of 36) on a per-patient basis.


CONCLUSIONS
On a per-patient basis, 64-section multi-detector row CT coronary angiography enables the diagnosis of significant (>or=50%) stenosis in CAD with an accuracy of 89%. On a per-segment and per-vessel basis, diagnostic accuracy is still impaired, primarily by limited spatial resolution.
Herzog
Christopher
C
Department of Radiology, Medical University of South Carolina, 169 Ashley Ave, Charleston, SC 29425, USA.
Zwerner
Peter L
PL
Doll
Josh R
JR
Nielsen
Christopher D
CD
Nguyen
Shaun A
SA
Savino
Giancarlo
G
Vogl
Thomas J
TJ
Costello
Philip
P
Schoepf
U Joseph
UJ
D000328:Adult; D000368:Aged; D016009:Chi-Square Distribution; D003287:Contrast Media; D017023:Coronary Angiography / Q000379:methods*; D023921:Coronary Stenosis / Q000000981:diagnostic imaging* / Q000473:pathology; D004562:Electrocardiography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed
D003287:Contrast Media