[Visualization of coronary tree and detection of coronary artery stenosis using 16-slice, sub-millimeter computed...

multislice CT has been shown as a promising tool for coronary artery imaging. Our goal was to investigate the value of the new sixteen-slice, CT technology for non-invasive visualization of coronary arteries and assessment of coronary stenosis.

we assessed coronary artery visualization in 30 consecutive patients using 16-slice CT and compared the findings with conventional coronary angiography. The whole heart was scanned using 0.75 millimeter slices after injection of contrast medium. Retrospective ECG-gated reconstructions were performed and images were analyzed using axial CT, maximum intensity projection and 3D images, blind to the conventional angiography findings. Seventeen main coronary segments of more than 1.5 mm were analyzed and stenosis was graded on a four-point scale.

CT angiography attained diagnostic quality for the whole coronary artery tree in 90% (27/30) of patients. Sixteen of 493 segments (4%) were not interpreted because of substantial motion artifacts (n=12) or heavy calcifications or stenting (n=4). Thirty seven of the 43 cases of significant stenosis (>50%) identified on coronary angiograms were correctly identified with multislice CT. All 6 false negatives involved stenosis of the circumflex artery or branches. Five false positive stenoses were found in 432 non stenotic segments. The sensitivity was thus 86%, specificity 99% for stenosis of more than 50%.

16-slice CT provides an excellent visualization of the coronary tree in most patients, allowing accurate non-invasive detection of significant coronary stenosis. Stenoses of the left circumflex artery remain more difficult to detect.