Accuracy of quantitative coronary angiography with computed tomography and its dependency on plaque composition: plaque composition and accuracy of cardiac CT.
OBJECTIVE
To determine the impact of plaque composition on accuracy of quantitative 64-slice computed tomography coronary angiography (CTCA).


METHODS
The institutional review board approved this study; written informed consent was obtained from all patients. One hundred consecutive patients (42 women, mean age 64.6 +/- 9.4 years, age range 39-87 years) underwent CTCA and invasive quantitative coronary angiography (QCA) to determine (a) the diagnostic accuracy of CTCA for the detection of significant stenosis (diameter reduction of > or =50%), and (b) the accuracy of stenosis grading. In CTCA stenosis severity was graded in 10% steps and evaluated separately for calcified and non-calcified coronary lesions using Pearson-linear-regression analysis, Bland/Altman-analysis (BA), and Mann-Whitney-U-test.


RESULTS
In 60/100 patients 139 significant coronary artery stenoses were identified with QCA. On a per-segment analysis, sensitivity of CTCA was 75.5%, and specificity was 96.6% (positive predictive value: 72.9%, negative predictive value: 97.0%). Quantification of stenosis grading correlated moderately between methods (r = 0.60; P < 0.001), with an overestimation by CTCA of 5.5% (BA limits-of-agreement -29 to 39%). BA limits-of-agreement were greater in calcified lesions (-29.2 to 45.6%; mean error 8.2%) than in non-calcified lesions (-25.9 to 30.2%; mean error 2.2%) and differed significantly (P < 0.05).


CONCLUSIONS
Diagnostic accuracy of CTCA is high, however agreement for quantitative lesion severity assessment between CTCA and QCA is moderate for calcified but superior for non-calcified lesions.
Cardiovascular Center, University Hospital Zurich, Zurich, Switzerland.
Lars
L
Husmann
Oliver
O
Gaemperli
Tiziano
T
Schepis
Hans
H
Scheffel
Ines
I
Valenta
Tobias
T
Hoefflinghaus
Paul
P
Stolzmann
Lotus
L
Desbiolles
Bernhard A
BA
Herzog
Sebastian
S
Leschka
Borut
B
Marincek
Hatem
H
Alkadhi
Philipp A
PA
Kaufmann
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016009:Chi-Square Distribution; D017023:Coronary Angiography / Q000379:methods*; D023921:Coronary Stenosis / Q000000981:diagnostic imaging* / Q000473:pathology; D005260:Female; D006801:Humans; D016014:Linear Models; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity; D018709:Statistics, Nonparametric; D014057:Tomography, X-Ray Computed / Q000379:methods*