导管超声辐照犬心肌组织的生物效应

探索导管超声在活体犬心腔内辐照心肌的可行性,及辐照后对心肌组织、细胞的生物效应.研制超声辐照导管在X线影像引导下经介入法进入活体犬左心室腔,在心腔内以频率4.3 MHz、声能1w/cm2的超声照射心肌1 min;即刻观察超声照射后血流动力学、心肌组织和细胞病理形态、超微结构的变化.导管超声辐照后光镜见心肌轻微充血,电镜发现线粒体普遍轻微肿胀,毛细血管内皮细胞间隙增宽,肌浆网扩张;血流动力学检测则显示有心肌收缩增强的趋势.超声辐照导管在心腔内辐照活体心肌安全可行,具有增加细胞膜及毛细血管通透性等生物效应、并且未产生毒副效应.

Biological Effect of Catheter-based Ultrasound Irradiating dog's Myocardium

This paper investigates the biological effect of intracardiac ultrasound irradiating myocardium in dogs.A ultrasound catheter was inserted into the dog's left ventricular chamber and the therapeutic ultrasound energy(1w/cm2,one minute)was delivered.The immediate change of myocardial pathobiology and microstructure were observed,meanwhile hemodynamics was measured.Compared with controls,mitochondria generally little swell,capillary endothelium cell also swell after the dogs were irradiated by ultrasound.In general,intracardiac ultrasound irradiating myocardium can enhance the permeability of capillary and myocardial cell membrane,which may be a new,safe and effective method for interventional ultrasound therapy of cardiovascular disease.