Detection of Coronary Artery Stenoses by Contrast-Enhanced, Retrospectively Electrocardiographically-Gated, Multislice Spiral Computed Tomography Stephan Achenbach, Tom Giesler, Dieter Ropers, Stefan Ulzheimer, Hans Derlien, Christoph Schulte, Evelyn Wenkel, Werner Moshage, Werner Bautz, Werner G. Daniel Willi A. Kalender, Ulrich Baum, Department of Internal Medicine II , the Institute of Medical Physics , and the Institute of Diagnostic Radiology, University of Erlangen-Nürnberg, Germany. Circulation, May 29, 2001;103;2535

Background:

 Multislice spiral computed tomography (MSCT) with retrospectively ECG-gated image reconstruction permits coronary artery visualization. We investigated the method’s ability to identify high-grade coronary artery stenoses and occlusions.

Methods:

A total of 64 consecutive patients were studied by MSCT (4x1 mm cross-sections, 500-ms rotation, table feed 1.5 mm/rotation, intravenous contrast agent, retrospectively ECG-gated image reconstruction). All coronary arteries and side branches with a luminal diameter 2.0 mm were assessed concerning evaluability and the presence of high-grade stenoses (>70% diameter stenosis) or occlusions. Results were compared with quantitative coronary angiography.

Results:

Of 256 coronary arteries (LM, LAD, CIRC, RCA including their respective side branches), 174 could be evaluated (68%).

In 19 patients out of 64 patients (30%), all arteries were evaluable. Artifacts caused by coronary motion were the most frequent reason for unevaluable arteries.

Overall, 32 of 58 high-grade stenoses and occlusions were detected by MSCT (58%). In evaluable arteries, 32 of 35 lesions were detected, and the absence of stenosis was correctly identified in 117 of 139 arteries (sensitivity, 91%; specificity, 84%). If analysis was extended to all stenoses with >50% diameter reduction, sensitivity was 85% (40 of 47) and specificity was 76% (96 of 127).

Conclusions:

MSCT with retrospective ECG gating permits the detection of coronary artery stenoses with high accuracy if image quality is sufficient, but its clinical use may presently be limited due to degraded image quality in a substantial number of cases, mainly due to rapid coronary motion.

EDITORIAL COMMENT:

In addition to the excitement over the FDA market clearance for Electron Beam Angiography, EBCT is now the ‘gold standard’ for determining coronary artery calcium levels. The calcium score would be critical and act as an effective tool for measuring and tracking coronary calcium levels in the beating heart. An important difference between EBCT and mechanical Multi-slice CT (MSCT) is the significantly faster speeds, better contrast to noise ratio, and less radiation with EBCT.

There are over 300 published studies that substantiate the effectiveness of Electron Beam Tomography in aiding clinicians in diagnosing and managing coronary artery disease.