Kraitchman D L, Wilke N, Hexeberg E, Jerosch-Herold M, Wang Y, Parrish T B, Chang C N, Zhang Y, Bache R J, Axel L
Department of Radiology, University of Pennsylvania, Philadelphia 19104-6021, USA.
Magn Reson Med. 1996 May;35(5):771-80. doi: 10.1002/mrm.1910350519.
MRI studies of first-pass contrast enhancement with polylysine-Gd-DTPA and myocardial tagging using spatial modulation of magnetization (SPAMM) were performed to assess the feasibility of a combined regional myocardial blood flow and 2D deformation exam. Instrumented closed-chest dogs were imaged at a baseline control state (Cntl) followed by two interventions: moderate coronary stenosis (St) achieved by partial occlusion of the left anterior descending (LAD) and moderate coronary stenosis with dobutamine loading (StD). Hypoperfusion of the anterior region (ANT) of the myocardium (LAD distribution) relative to the posterior wall (POS) based on the upslope of the signal intensity time curve from the contrast-enhanced MR images was demonstrated only with dobutamine loading (ANT:POS Cntl = 1.077 +/- 0.15 versus ANT:POS StD = 0.477 +/- 0.11, P < 0.03) and was confirmed with radiolabeled microspheres measurements (ANT:POS Cntl = 1.18 +/- 0.2 ml/min/g versus ANT:POS StD = 0.44 +/- 0.1 ml/min/g; P < 0.002). Significant changes in regional myocardial shortening were only seen in the StD state (P < 0.02); the anterior region showed impaired myocardial shortening with dobutamine loading (P = NS), whereas the nonaffected POS region showed a marked increase in shortening when compared with Cntl (Cntl = 0.964 +/- 0.02 versus StD = 0.884 +/- 0.03; P < 0.001). These results demonstrate that an integrated quantitative assessment of regional myocardial function and semiquantitative assessment of myocardial blood flow can be performed noninvasively with ultrafast MRI.
使用聚赖氨酸 - 钆 - 二乙三胺五乙酸（polylysine-Gd-DTPA）进行首次通过对比增强的磁共振成像（MRI）研究，并采用磁化空间调制（SPAMM）技术进行心肌标记，以评估联合区域心肌血流和二维变形检查的可行性。对开胸植入仪器的犬在基线对照状态（Cntl）下进行成像，随后进行两种干预：通过部分闭塞左前降支（LAD）实现中度冠状动脉狭窄（St），以及在中度冠状动脉狭窄基础上进行多巴酚丁胺负荷试验（StD）。基于对比增强磁共振图像的信号强度时间曲线的上升斜率，仅在多巴酚丁胺负荷试验时显示心肌前壁区域（ANT，LAD分布）相对于后壁（POS）存在灌注不足（ANT:POS Cntl = 1.077 +/- 0.15 对比 ANT:POS StD = 0.477 +/- 0.11，P < 0.03），并且放射性微球测量结果也证实了这一点（ANT:POS Cntl = 1.18 +/- 0.2 ml/min/g 对比 ANT:POS StD = 0.44 +/- 0.1 ml/min/g；P < 0.002）。仅在StD状态下观察到区域心肌缩短有显著变化（P < 0.02）；前壁区域在多巴酚丁胺负荷试验时显示心肌缩短受损（P = 无统计学意义），而未受影响的后壁区域与Cntl相比缩短明显增加（Cntl = 0.964 +/- 0.02 对比 StD = 0.884 +/- 0.03；P < 0.001）。这些结果表明，使用超快MRI可以无创地对区域心肌功能进行综合定量评估以及对心肌血流进行半定量评估。
