Mao S, Lu B, Oudiz R J, Bakhsheshi H, Liu S C, Budoff M J
Harbor-UCLA Research and Education Center, Torrance, CA, USA.
J Comput Assist Tomogr. 2000 Mar-Apr;24(2):253-8. doi: 10.1097/00004728-200003000-00012.
The purpose of this work was to evaluate coronary artery motion characteristics and determine optimal electron beam tomography (EBT) scan time during the cardiac cycle to image the coronary arteries.
This study evaluated the movement of coronary arteries in 20 EBT cine studies, at rest and during stress, obtained for evaluating coronary artery disease. The proximal, middle, and distal segments of each coronary artery were measured at multiple times during the cardiac cycle. The motion distance (mm) and velocity (mm/s) of each segment of the coronary arteries were then measured to establish the motion that occurs in the x and y axes during different times in the cardiac cycle.
Coronary artery velocity ranged from 22.4 to 108.6 mm/s. The least motion (and slowest speed) occurred between 30-50 and 40-60% of the R-R interval at rest and stress, respectively. The right coronary artery moved the greatest in the x and y planes (highest speed and spatial change), followed in decreasing order by the circumflex, left main, and left anterior descending arteries. The phase of the cardiac cycle with the greatest coronary artery motion was between 0 and 20% of the R-R interval.
Coronary artery motion varies greatly throughout the cardiac cycle. To minimize cardiac motion during tomographic imaging of the coronary arteries, we recommend 40-50% R-R interval as an electrocardiographic trigger time and avoiding the use of image acquisition times of >100 ms.
本研究的目的是评估冠状动脉的运动特征，并确定心动周期中用于冠状动脉成像的最佳电子束断层扫描（EBT）扫描时间。
本研究评估了20例用于评估冠状动脉疾病的EBT电影研究中，静息和负荷状态下冠状动脉的运动情况。在心动周期的多个时间点测量每条冠状动脉的近端、中段和远端节段。然后测量冠状动脉各节段的运动距离（mm）和速度（mm/s），以确定心动周期不同时间在x轴和y轴上发生的运动。
冠状动脉速度范围为22.4至108.6 mm/s。静息和负荷状态下，运动最少（速度最慢）分别出现在R-R间期的30 - 50%和40 - 60%之间。右冠状动脉在x轴和y平面上的移动最大（速度最高和空间变化最大），其次依次为回旋支、左主干和左前降支动脉。冠状动脉运动最大的心动周期阶段在R-R间期的0至20%之间。
冠状动脉运动在整个心动周期中变化很大。为了在冠状动脉断层成像期间将心脏运动降至最低，我们建议将40 - 50%的R-R间期作为心电图触发时间，并避免使用大于100 ms的图像采集时间。
