Natanzon Alex, Aletras Anthony H, Hsu Li-Yueh, Arai Andrew E
Laboratory of Cardiac Energetics, National Heart, Lung, and Blood Institute, National Institutes of Health, U.S. Department of Health and Human Services, 10 Center Dr, MSC 1061, Bldg 10, Room B1D-416, Bethesda, MD 20892-1061, USA.
Radiology. 2005 Sep;236(3):859-66. doi: 10.1148/radiol.2363040413.
To test whether manganese-enhanced magnetic resonance (MR) imaging can safely depict the myocardial area at risk both during coronary artery occlusion and for at least 2 hours after reperfusion in dogs.
All procedures were performed in accordance with the animal care and use committee of the National Institutes of Health. In eight dogs, the left anterior descending (LAD) coronary artery was occluded for 90 minutes, and 15 micromol of MnCl2 per kilogram of body weight was intravenously infused for 12 minutes. Phase-sensitive inversion-recovery MR imaging of the LAD arterial territory was performed before occlusion, during MnCl2 infusion, and for at least 2 hours after reperfusion. Hemodynamic responses were monitored continuously. Fluorescent microsphere enhancement was used as the reference standard for determining the area at risk ex vivo. Results are reported as percentages of left ventricular area. Correlation, Bland-Altman, and t test analyses were performed.
Significant differences in manganese-induced contrast enhancement of the area at risk, the normal myocardium, and the blood (P < .01) were measured during LAD artery occlusion and at least 2 hours after reperfusion. No significant changes in heart rate or blood pressure were detected during or after MnCl2 infusion. Measurements of the area at risk obtained with manganese-enhanced MR imaging during LAD artery occlusion and 2 hours after reperfusion correlated well with the size of the at-risk area demarcated by the fluorescent microspheres (during occlusion: y = 0.81x, R = 0.90; during reperfusion: y = 0.83x, R = 0.89). Bland-Altman analysis revealed small systematic errors in measurements at both occlusion and reperfusion.
Manganese-enhanced MR imaging can depict the area at risk during LAD artery occlusion and at least 2 hours after reperfusion without hemodynamic compromise.
测试锰增强磁共振（MR）成像能否安全地描绘犬冠状动脉闭塞期间及再灌注后至少2小时内心肌危险区域。
所有操作均按照美国国立卫生研究院动物护理和使用委员会的规定进行。对8只犬，闭塞左前降支（LAD）冠状动脉90分钟，每千克体重静脉输注15微摩尔氯化锰12分钟。在闭塞前、氯化锰输注期间及再灌注后至少2小时，对LAD动脉供血区域进行相敏反转恢复MR成像。持续监测血流动力学反应。荧光微球增强法用作离体确定危险区域的参考标准。结果以左心室面积的百分比报告。进行了相关性、Bland-Altman和t检验分析。
在LAD动脉闭塞期间及再灌注后至少2小时，测量到锰诱导的危险区域、正常心肌和血液的对比增强存在显著差异（P <.01）。在氯化锰输注期间或之后，未检测到心率或血压有显著变化。LAD动脉闭塞期间及再灌注后2小时，用锰增强MR成像获得的危险区域测量值与荧光微球划定的危险区域大小相关性良好（闭塞期间：y = 0.81x，R = 0.90；再灌注期间：y = 0.83x，R = 0.89）。Bland-Altman分析显示在闭塞和再灌注时测量均存在小的系统误差。
锰增强MR成像可描绘LAD动脉闭塞期间及再灌注后至少2小时的危险区域，且不影响血流动力学。
