中华小型猪心肌微循环障碍的影像学研究

目的：MSCT、MRI和SPECT对中华小型猪心肌微循环障碍的显示效果。方法：中华小型猪8只，全部雄性，体重（22．8±0．9）kg。实验猪接受MSCT扫描1次后1周内于前降支中远段注射105直径约100um微球，术后27天行SPECT，28天行造影、MSCT和MRI检查各1次，最后处死动物送病理检查。结果：4只实验猪死亡，其余4只完成所有检查。病理染色未均见梗死。术前与术后28天MSCT扫描测量每搏输出量、收缩末期容积、舒张末期容积和射血分数的差异均无统计学意义（P〉0．05）。术前与术后28天的MSCT扫描测量左室前壁、左室侧壁及室间隔的平均CT值在动脉期、延迟1、3、5和10min自身对照均没有统计学差异。术后28天的左室前壁、左室侧壁及室间隔在MSCT动脉期均未见异常灌注减低区域，延迟扫描也未出现强化；MRI均未见异常灌注减低区域，延迟扫描也未见强化；SPECT扫描示上述区域均未见明显灌注减低区域。结论：MSCT、MRI和SPECT对于没有明显病理染色的梗死区域及心功能变化的微循环障碍显示是受限的。

Comprehensive Imaging Study of Myocardial Microcirculation Disturbance in Chinese Mini-swine Model

Objective：To study the efficacy of multi-detector row computed tomography （MSCT） ,magnetic resonance imaging （MRI） and single photon emission computed tomography （SPECT） in the demonstration of myocardial microcirculation disturbance in Chinese mini-swine model. Methods：Eight male Chinese mini swines with the body weight as （22.8 ± 0.9） kg were chosen. MSCT was performed before the experiment, then within 1 week, 105 microspheres with the diameter of about 100um were injected into the middle/distal segment of left anterior descending coronary artery. On the 27th day after injection, SPECT was performed. On the 28th day, coronary imaging, including MSCT, MRI were undertaken. All of the experimental animals were sacrificed for pathology examination. Results：Four pigs died and could not fulfill the requirement of experiment,another 4 completed the whole process. No infarction was detected by pathology examination. No statistical differences were showed in the stroke volume, end systolic volume, end diastolic volume and ejection fraction before and after the 28th day of the operation （P〉0.05） ;The average CT value of lateral wall of left ventricle,anterior wall of left ventricle and interventricular septum at the arterial phase, delayed lmin, 3min, 5min, 10min and the 28th postoperative day＇ measured on MSCT didn＇t showed statistical differences as well. All the abovementioned areas had neither abnormally decreased perfusion regions in the arterial phase nor enhancement in delayed phases. Neither abnormally decreased perfusion regions nor enhancement in delayed phases were shown on MRI. SPECT showed no low perfusion regions in the above-mentioned regions. Conclusion： The role of MSCT, MRI, SPECT were limited in the detection of myocardial microcirculation disturbance with no apparent infarct changes on pathology or impaired cardiac function.