Non-invasive half millimetre 32 detector row computed tomography angiography accurately excludes significant stenoses in patients with advanced coronary artery disease and high calcium scores.
OBJECTIVE
To show an overall diagnostic accuracy > or = 90% for detection of > or = 50% stenoses by coronary half millimetre 32 detector row computed tomography angiography (32 x 0.5-MDCTA) in patients with advanced coronary artery disease (CAD) and a high likelihood of raised calcium scores.


METHODS
ECG gated 32 x 0.5-MDCTA (32 x 0.5 mm cross sections, 0.35 x 0.35 x 0.35 mm3 isotropic voxels, 400 ms rotation) was performed after injection of iodixanol (120 ml, 320 mg/ml) in 30 consecutive patients (25 men, mean (SD) age 59 (13) years, body mass index 26.2 (4.9) kg/m2). Native arteries, including > or = 1.5 mm branches, and bypass grafts were screened for > or = 50% stenoses. Stents were excluded. Conventional coronary angiography (performed 18 (12) days before 32 x 0.5-MDCTA) was analysed by quantitative coronary angiography.


RESULTS
Median Agatston calcium score was 510 (range 3-5066). Sensitivity, specificity, and positive and negative predictive values for detection of > or = 50% stenoses in native arteries were 76% (29 of 38), 94% (190 of 202), 71% (29 of 41), and 96% (190 of 199), respectively. Overall diagnostic accuracy was 91% (219 of 240). Due to the following artefacts 20% (69 of 352) of the vessels were excluded: motion, noise, and low contrast enhancement isolated or in combination (45 of 69 (65%)); image distortion by implantable cardioverter-defibrillator or pacemaker leads (18 of 69 (26%)); and blooming secondary to severe calcification (6 of 69 (9%)).


CONCLUSIONS
Coronary 32 x 0.5-MDCTA accurately excludes > or = 50% stenoses in patients with advanced CAD and high calcium scores with an overall diagnostic accuracy of 91%.
Cordeiro
M A S
MA
Division of Cardiology, Department of Medicine, The Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
Miller
J M
JM
Schmidt
A
A
Lardo
A C
AC
Rosen
B D
BD
Bush
D E
DE
Brinker
J A
JA
Bluemke
D A
DA
Shapiro
E P
EP
Lima
J A C
JA
D000328:Adult; D000368:Aged; D016477:Artifacts; D002114:Calcinosis / Q000000981:diagnostic imaging; D009202:Cardiomyopathies / Q000000981:diagnostic imaging*; D017023:Coronary Angiography / Q000379:methods*; D023921:Coronary Stenosis / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods* / Q000592:standards