Klein Christoph, Nekolla Stephan G, Bengel Frank M, Momose Mitsuru, Sammer Andrea, Haas Felix, Schnackenburg Bernhard, Delius Wolfram, Mudra Harald, Wolfram Dieter, Schwaiger Markus
Nuklearmedizinische Klinik und Poliklinik der Technischen Universität München, Germany.
Circulation. 2002 Jan 15;105(2):162-7. doi: 10.1161/hc0202.102123.
Recent studies indicate that MRI, after administration of gadolinium-diethylenetriamine pentaacetic acid, can identify nonviable areas in dysfunctional myocardium. We compared MRI hyperenhancement with PET as a gold standard for detection and quantification of myocardial scar tissue.
Thirty-one patients with ischemic heart failure (ejection fraction, 28+/-9%) were imaged with PET and MRI. Scar was defined as regionally increased MRI signal intensity 20 minutes after injection of 0.2 mmol/kg gadolinium-diethylenetriamine pentaacetic acid and as concordantly reduced perfusion and glucose metabolism as defined by PET. Sensitivity and specificity of MRI in identifying patients and segments (n=1023) with matched flow/metabolism defects was 0.96 of 1.0 and 0.86 of 0.94, respectively. Eleven percent of segments defined as viable by PET showed some degree of MRI hyperenhancement. Defect severity score based on visual analysis was 44.3+/-9.1 for PET and 47.6+/-11.1 for MRI (r=0.91, P<0.0001). Quantitatively assessed relative MRI infarct mass correlated well with PET infarct size (r=0.81, P<0.0001). Furthermore, MRI hyperenhancement was a better predictor of scar tissue than end-diastolic and end-systolic wall thickness or thickening.
In severe ischemic heart failure, MRI hyperenhancement as a marker of myocardial scar closely agrees with PET data. Although hyperenhancement correlated with areas of decreased flow and metabolism, it seems to identify scar tissue more frequently than PET, reflecting the higher spatial resolution. Additional functional studies after revascularization are required to define the significance of small islands of scar detected by MRI.
近期研究表明，静脉注射钆喷酸葡胺后行MRI检查，可识别功能失调心肌中的无活性区域。我们将MRI强化与作为检测和定量心肌瘢痕组织金标准的PET进行了比较。
对31例缺血性心力衰竭患者（射血分数为28±9%）进行了PET和MRI检查。瘢痕定义为静脉注射0.2 mmol/kg钆喷酸葡胺20分钟后MRI信号强度区域性增加，以及PET所定义的灌注和葡萄糖代谢一致降低。MRI识别具有匹配血流/代谢缺陷的患者和节段（n = 1023）的敏感性和特异性分别为0.96（共1.0）和0.86（共0.94）。PET定义为存活的节段中有11%表现出一定程度的MRI强化。基于视觉分析的缺损严重程度评分，PET为44.3±9.1，MRI为47.6±11.1（r = 0.91，P<0.0001）。定量评估的相对MRI梗死质量与PET梗死大小相关性良好（r = 0.81，P<0.0001）。此外，与舒张末期和收缩末期室壁厚度或增厚相比，MRI强化是瘢痕组织更好的预测指标。
在严重缺血性心力衰竭中，MRI强化作为心肌瘢痕的标志物与PET数据高度一致。虽然强化与血流和代谢降低的区域相关，但它似乎比PET更频繁地识别瘢痕组织，这反映了更高的空间分辨率。血运重建后的额外功能研究需要确定MRI检测到的小瘢痕岛的意义。
