负荷心肌超声造影评价糖尿病大鼠早期心肌灌注演变规律

Development of early myocardial perfusion in diabetic rats： the stress myocardial contrast echocardiography study

目的应用实时心肌超声造影（MCE）结合潘生丁负荷研究早期糖尿病（DM）大鼠心肌灌注障碍的发生、发展过程和演变规律。方法对照组和DM组各40只大鼠，分为0周、2周、4周和8周四个亚组，于DM成模后不同时间点进行常规超声、MCE并结合潘生丁负荷检查，对各个时间点对照组和DM组两组间各项参数进行比较，同时对组内各个时间点参数进行比较。结果静息MCE指标显示最早从8周亚组可以检出DM组的心肌血容量和心肌血流量的指标较对照组明显减低。潘生丁负荷后DM组从4周亚组开始血流速度储备和心肌血流量储备较对照组减低，8周亚组的三项储备指标均较对照组明显减低，而且三项血流储备指标也不同程度的有随病程延长而降低的趋势。结论MCE结合负荷超声可较早地检出DM大鼠的心肌灌注障碍。

Objective To investigate the development of early myocardial perfusion with myocardial contrast echocardiography （MCE） combined with dipyridamole stress echocardiography in diabetic rats. Methods The diabetes mellitus （DM） group comprised 40 male diabetic rats,induced with streptozotocin. The control group comprised 40 normal male rats,comparable body weights with the DM group. The DM group was divided into four subgroups （6 week, 2 weeks, 4 weeks and 8 weeks after diabetic model established） and the control group was also divided into four subgroups matched with the DM group. Each rat was performed with conventional echocardiography,MCE at baseline and after dipyridamole stress. The reserve parameters were compared between the control group and the DM group. In addition,the differences among four subgroups in the control group and the DM group were compared, respectively. Results MCE demonstrated that the 4 weeks and 8 weeks DM subgroup had lower myocardial blood velocity reserve and myocardial blood flow reserve than the control subgroup. The myocardial blood volume reserve was reduced in the 8 weeks DM subgroup,too. Conclusions The impairment of myocardial perfusion in the DM rats are detected earlier with the MCE combined with dipyridamole stress.