Achenbach S, Moshage W, Ropers D, Nossen J, Bachmann K
Medizinische Klinik II, Universitat Erlangen Nurnberg (Department of Cardiology), Germany.
Am J Cardiol. 1997 Apr 1;79(7):856-61. doi: 10.1016/s0002-9149(97)00003-9.
Electron beam tomography (EBT, ultrafast computed tomography [CT], cine CT) combines unique temporal and high spatial resolution and is especially well suited for cardiac imaging. We established and evaluated a protocol for the noninvasive visualization and assessment of aortocoronary artery bypass grafts. Twenty-five patients with 56 bypass grafts were studied by EBT. Forty contiguous cross-sectional images were acquired triggered to the electrocardiogram during breathhold and intravenous injection of contrast agent. Three-dimensional reconstructions of the heart and bypass grafts were performed and compared with selective angiography of the bypass grafts. In 1 patient with 2 bypass grafts, a technically inadequate EBT examination was obtained. In the remaining patients (54 grafts), all 13 bypass occlusions were diagnosed with a sensitivity and specificity of 100%. Evaluation for hemodynamically relevant stenosis was possible in 84% of cases (36 of 43 patent grafts) and yielded a sensitivity of 100% (5 of 5 high-grade stenoses correctly detected) and specificity of 97% (1 false-positive diagnosis of high-grade graft stenosis). The main reasons for impaired ability to evaluate the scans were breathing artifacts and misplacement of the imaging volume, causing parts of the bypass grafts to be cut off. EBT permits noninvasive determination of bypass graft occlusion and relevant stenosis with high accuracy.
电子束断层扫描（EBT，超速计算机断层扫描[CT]，电影CT）结合了独特的时间分辨率和高空间分辨率，特别适合心脏成像。我们建立并评估了一种用于无创可视化和评估主动脉冠状动脉旁路移植术的方案。对25例患者的56条旁路移植血管进行了EBT研究。在屏气和静脉注射造影剂期间，触发心电图采集40幅连续的横断面图像。对心脏和旁路移植血管进行三维重建，并与旁路移植血管的选择性血管造影进行比较。1例有2条旁路移植血管的患者，EBT检查技术上不充分。在其余患者（54条移植血管）中，所有13条旁路移植血管闭塞均被诊断，敏感性和特异性均为100%。84%的病例（43条通畅移植血管中的36条）能够对血流动力学相关狭窄进行评估，敏感性为100%（正确检测出5条高度狭窄中的5条），特异性为97%（1例假阳性诊断为高度移植血管狭窄）。扫描评估能力受损的主要原因是呼吸伪影和成像容积放置不当，导致部分旁路移植血管被截断。EBT能够高精度地无创确定旁路移植血管闭塞和相关狭窄。
