心肌声学造影和背向散射组织定征对犬顿抑心肌的研究

Study of Dog Stunned Myocardium by Myocardial Contrast Echocardiography and Integrared Backscatter Myocardial Tissue Characterization

目的 研究犬顿抑心肌模型的血流灌注图像和背向散射组织定征信号的变化。方法 对 9条健康杂种犬通过结扎左冠状动脉前降支 (LAD)制作顿抑心肌模型 ,检测LAD结扎前、结扎后不同时间顿抑心肌图像的平均强度(AII)及背向散射积分周期变化幅度 (CVIB)。观察心肌血流灌注显像。结果 LAD供血区域心肌的AII值、CVIB值及心肌血流灌注图像在LAD结扎前、结扎时、恢复再灌注后不同时间内发生了一系列变化。结论 心肌声学造影可清楚显示心肌的血流灌注状态 ,帮助判断冠脉支的走行和分布 ;背向散射心肌组织定征在评价不同血供状态。

Objective To study the alteration of myocardial perfusion imaging and integrated backscatter tissue characterization of dog stunned myocardium. Methods 9 health mongrel dogs were constructed into stunning myocardial models by ligating left anterior descending branch (LAD) of coronary artery. The average image intensity(AII) and the cyclic variation of integrated backscatter (CVIB) and myocardial perfusion imaging before and after LAD ligation, and after release of ligature. Results AII and CVIB and myocardial perfusion imaging of regional myocardium which was supplied by LAD were presented a series of changes in various times. Conclusion Myocardial contrast echocardiography can clearly show the myocardial perfusion degree and help examiner to judge indirectly the running direction and distribution of coronary artery branches. Integrated backscatter tissue characterization is of great value for appraising the ultrasonic signal changes of small scattering bodies and its geometric shape of myocardium under different blood flow condition in cardiac cycle.