Detection of coronary artery stenoses by contrast-enhanced, retrospectively electrocardiographically-gated, multislice spiral computed tomography

Background-Multislice spiral computed tomography (MSCT) with retrospectivel y EGG-gated image reconstruction permits coronary artery visualization. We investigated the method's ability to identify high-grade coronary artery st enoses and occlusions. Methods and Results-A total of 64 consecutive patients were studied by MSCT (4x1 mm cross-sections, 500-ms rotation, table feed 1.5 mm/rotation, intra venous contrast agent, retrospectively EGG-gated image reconstruction). All coronary arteries and side branches with a luminal diameter greater than o r equal to2.0 mm were assessed concerning evaluability and the presence of high-grade stenoses (>70% diameter stenosis) or occlusions. Results were co mpared with quantitative coronary angiography. Of 256 coronary arteries (le ft main, left anterior descending, left circumflex and right coronary arter y, including their respective side branches), 174 could be evaluated (68%). In 19 patients (30%), all arteries were evaluable. Artifacts caused by cor onary motion were the most frequent reason for unevaluable arteries. Overal l, 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% diam eter reduction, sensitivity was 85% (40 of 47) and specificity was 76% (96 of 127). Conclusions-MSCT with retrospective EGG gating permits the detection of cor onary artery stenoses with high accuracy if image quality is sufficient, bu t its clinical use may presently be limited due to degraded image quality i n a substantial number of cases, mainly due to rapid coronary motion.