Assessment of myocardial salvage after ischemia and reperfusion using magnetic resonance imaging and spectroscopy.
Assessment of myocardial salvage after ischemia and reperfusion using magnetic resonance imaging and spectroscopy.
复制标题
DOI：
10.1161/01.cir.80.4.969
复制
发表时间：
1989-10
期刊：
影响因子：
37.8
通讯作者：
Christopher L. Wolfe;M. Moseley;Mats Wikström;Richard E. Sievers;Michael F. Wendland;J. Dupon;WALTER E. Finkbeiner;MARTIN J. Lipton;W. W. Parmley-W.;R. Brasch
中科院分区：
文献类型：
--
作者：
Christopher L. Wolfe;M. Moseley;Mats Wikström;Richard E. Sievers;Michael F. Wendland;J. Dupon;WALTER E. Finkbeiner;MARTIN J. Lipton;W. W. Parmley-W.;R. Brasch
为了验证对比增强磁共振成像（MRI）和磁共振波谱（MRS）可以区分可逆性和不可逆性心肌损伤的假设，这些模式被用来研究大鼠模型的缺血和再灌注。用放射性标记的微球证实缺血和再灌注的存在（n = 6）。对动物组进行16（n = 17）、30（n = 14）、60（n = 11）或90（n = 14）分钟的左冠状动脉（LCA）闭塞和60分钟的再灌注。注射白蛋白-钆（Gd）-DTPA后，在基线时以及在LCA闭塞和再灌注期间每16分钟采集一次对比度增强、T1加权、自旋回波质子图像。在单独的实验中，在缺血和再灌注期间的相似时间点获得31磷（31 P）光谱。闭塞16分钟后，MRI显示正常灌注心肌与缺血心肌相比显著增强（104 +/- 7.9% vs. 61 +/-11.0%，p <0.05，n = 5，平均值+/- SEM，基线值的%）。MRS显示磷酸肌酸（PCr）和三磷酸腺苷（ATP）减少（58.8 +/-2.4%，p ≤ 0.01; 81.4 +/- 2.4，p ≤ 0.01，n = 12）。缺血16或30分钟后，再流导致缺血区MRI信号强度与正常心肌相比均匀一致（93.5 ± 11.3 vs. 80.9 ± 7.0，p = NS，n = 11，再灌注30分钟时基线值的%）和MRS上的PCr恢复（94.3 +/-4.0%，p = NS，n = 20，30分钟复流时的%基线值）。在缺血60和90分钟后，与MRI上的正常心肌相比，再流导致再灌注显著增强（254.0 +/- 30.0 vs. 78.3 +/- 9.2，p小于或等于0.01，n = 10），MRS上的PCr没有恢复（64.1 +/- 3.0，p = NS，n = 14）。氯化三苯基四氮唑（TTC）染色显示，在所有的心脏进行60或90分钟的缺血和再灌注的透壁性心肌梗死（MI），只有2/11的心脏进行16或30分钟的缺血和再灌注的小的非透壁性MI。因此，1）使用白蛋白-Gd-DTPA的MRI可通过增强正常灌注和缺血心肌之间的对比度来识别心肌缺血; 2）使用白蛋白-Gd-DTPA的MRI可用于识别心肌缺血后的再灌注;以及3）再灌注后，可通过MRI和MRS上的特征性发现来区分可逆性心肌损伤和不可逆性心肌损伤。
To test the hypothesis that contrast-enhanced magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS) can differentiate reversible from irreversible myocardial injury, these modalities were used to study ischemia and reperfusion in a rat model. The presence of ischemia and reperfusion were confirmed with radiolabeled microspheres (n = 6). Groups of animals were subjected to either 16 (n = 17), 30 (n = 14), 60 (n = 11), or 90 (n = 14) minutes of left coronary artery (LCA) occlusion and 60 minutes reperfusion. After albumin-gadolinium (Gd)-DTPA injection, contrast-enhanced, T1-weighted, spin-echo proton images were acquired at baseline and every 16 minutes during LCA occlusion and reperfusion. In separate experiments, 31phosphorus (31P) spectra were acquired at similar time points during ischemia and reperfusion. After 16 minutes occlusion, normally perfused myocardium enhanced significantly compared with ischemic myocardium on MRI (104 +/- 7.9% vs. 61 +/- 11.0%, p less than 0.05, n = 5, mean +/- SEM, % of baseline value). MRS showed reduced phosphocreatine (PCr) and adenosine triphosphate (ATP) (58.8 +/- 2.4%, p less than or equal to 0.01; 81.4 +/- 2.4, p less than or equal to 0.01, n = 12). After 16 or 30 minutes ischemia, reflow resulted in uniform MRI signal intensity of the ischemic zone compared with normal myocardium (93.5 +/- 11.3 vs. 80.9 +/- 7.0, p = NS, n = 11, % of baseline value at 30 minutes reperfusion) and PCr recovery on MRS (94.3 +/- 4.0%, p = NS, n = 20, % baseline value at 30 minutes reflow). After 60 and 90 minutes ischemia, reflow resulted in marked enhancement of reperfused compared with normal myocardium on MRI (254.0 +/- 30.0 vs. 78.3 +/- 9.2, p less than or equal to 0.01, n = 10) and no recovery of PCr on MRS (64.1 +/- 3.0, p = NS, n = 14). Triphenyltetrazolium chloride (TTC) staining revealed transmural myocardial infarction (MI) in all hearts subjected to 60 or 90 minutes ischemia and reflow, and small nontransmural MIs in only 2/11 hearts subjected to 16 or 30 minutes ischemia and reperfusion. Thus, 1) MRI with albumin-Gd-DTPA is useful for identifying myocardial ischemia by enhancing the contrast between normally perfused and ischemic myocardia; 2) MRI with albumin-Gd-DTPA is useful for identifying reperfusion after myocardial ischemia; and 3) after reperfusion, reversible can be distinguished from irreversible myocardial injury by characteristic findings on MRI and MRS.