Noninvasive visualization of coronary arteries using contrast-enhanced multidetector CT: influence of heart rate on image quality and XXXX detection.

@entity1 @entity850
OBJECTIVE: Although multidetector CT (MDCT) with retrospectively ECG-gated image reconstruction has been shown to permit noninvasive visualization of the coronary arteries, the 125-250 msec required for image acquisition frequently causes motion artifacts. We investigated the influence of a @entity1 's heart rate on the presence of motion artifacts and on accuracy of @entity850 detection on contrast-enhanced MDCT. MATERIALS AND METHODS: In 100 @entity1 , MDCT was performed, and ECG-gated cross-sectional images were retrospectively reconstructed. From the 10 data sets obtained for each @entity1 (reconstructed at 0-90% of the cardiac cycle in increments of 10%), we chose the best data set for every coronary artery. The images of the arteries were evaluated for occurrence of artifacts and the presence of high-grade @entity850 (diameter reduction exceeding 70%) or occlusions. MDCT results were compared with coronary angiographic findings. RESULTS: Of the 400 coronary arteries, 115 (29%) could not be evaluated because of motion artifacts (n = 84) or other reasons (n = 31). Overall, 51 (49%) of 104 stenoses were revealed on MDCT. For detecting @entity850 in those arteries that we could evaluate, MDCT had a sensitivity of 91% (51 of 56 stenoses detected) and a specificity of 89%. As the heart rate increased, the number of arteries that could be evaluated decreased, and overall sensitivity for @entity850 detection decreased from 62% (heart rate < or = 70 beats per minute) to 33% (heart rate > 70 beats per minute). CONCLUSION: MDCT can reveal coronary stenoses, but the usefulness of MDCT as an aid in accurately evaluating stenoses decreases as a @entity1 's heart rate increases.
