Diagnostic accuracy in coronary stenosis: comparison between visual score and quantitative analysis (quantitative computed tomographic angiography) in coronary angiography by multidetector computed tomography-coronary angiography and quantitative analysis (quantitative coronary angiography) in conventional coronary angiography.
BACKGROUND
Multidetector computed tomography-coronary angiography allows quantification of coronary stenosis with a high level of accuracy; however, the inherent inaccuracy of visual score still remains. Computed quantitative vessel analysis systems (quantitative computed tomographic angiography [QCTA]) aim to overcome this limitation. The aim of our study was to evaluate the accuracy of QCTA in comparison with quantitative coronary angiography (QCA) and visual score using the QCA.


METHODS
Two operators visually scored 30 consecutive patients referred for multidetector computed tomography-coronary angiography to assess stenotic segments according to a modified 17-segment American Heart Association classification model. Coronary angiography was performed within 1 week. The degree of stenosis was classified as 0%, lower than 20% (wall irregularities), lower than 50% (without significant disease), and higher than 50% (significant disease). Each segment was then analyzed using electronic calipers of the QCTA system. Data were compared with QCA results. Each segment was finally classified as fibrofatty, mixed, and calcified. Comparisons between QCTA results, visual score, and QCA were performed by means of Spearman rank correlation. Interobserver variability is calculated using κ statistics.


RESULTS
From a total of 870 segments, 69 were diseased. Interobserver agreement between the 2 operators resulted very high (κ = 0.97). A good correlation was found between visual score and QCA (ρ = 0.932, P < 0.0001) and between visual score and QCTA (ρ = 0.845, P < 0.0001). A moderate correlation was found between QCTA and QCA (ρ = 0.810, P < 0.0001).


CONCLUSIONS
The accuracy of QCTA is comparable with that of QCA and visual score especially in noncalcified vessels. Editing of the vessel contours in case of calcified vessels is helpful in correctly estimating the right percentage of stenosis.
Malagò
Roberto
R
Department of Radiology, University of Verona-Policlinico GB Rossi, Verona, Italy. rmalag@sirm.org
D'Onofrio
Mirko
M
Tavella
Domenico
D
Mantovani
William
W
Brunelli
Silvia
S
Pezzato
Andrea
A
Caliari
Giuliana
G
Nicolì
Lisa
L
Benussi
Paolo
P
Mucelli
Roberto Pozzi
RP
D002114:Calcinosis / Q000000981:diagnostic imaging; D017023:Coronary Angiography / Q000379:methods*; D023921:Coronary Stenosis / Q000000981:diagnostic imaging* / Q000473:pathology; D006801:Humans; D010363:Pattern Recognition, Automated; D011446:Prospective Studies; D011857:Radiographic Image Interpretation, Computer-Assisted; D015203:Reproducibility of Results; D012720:Severity of Illness Index; D018709:Statistics, Nonparametric; D014057:Tomography, X-Ray Computed / Q000379:methods*