【摘要】 目的　采用声学密度法,观察实验动物犬心腔内不同类型造影剂后散射强度的变化,分析微气泡成分的不同对收缩期压力的敏感性。方法　经多巴酚丁胺逐步升压后,周围静脉分别注射声振白蛋白造影剂、Levovist和含氟碳造影剂,记录改变收缩期压力时不同类型造影剂的后散射二维图像,并与右室压力曲线同步。结果　收缩期压力对声振白蛋白造影剂和Levovist后散射强度之差(ED ES)的影响差异具有显著性意义(P<0.0001, P<0.02),对含氟碳造影剂后散射强度之差的影响差异无显著性意义(P=0.10)。收缩期压力与声振白蛋白造影剂后散射强度之差的相关性较好(r=0.64, P<0.0001),与Levovist的相关性次之(r=0.57,P=0.001),与含氟碳造影剂相关性差(r=0.41, P=0.07)。结论　造影剂微气泡外壳成分和内部气体的性质影响其对外周压力变化的敏感性。声振白蛋白微气泡外壳弹性较好,内含可压缩的空气,对收缩期压力变化的敏感性较高,Levovist次之,含氟碳造影剂外壳较坚硬,对压力变化的敏感性低。更多还原

【Abstract】 Objective To observe the intracardiac backscatter intensities changes of different contrasts in dogs and analyze the systolic pressure sensitivity from different contrast agents using acoustic densitometry. Methods Ventricular pressure was increased by administration of dobutamine (β1-adrenoceptor agonist). And sonicated albumin microbubbles, levovist and perfluorocarbon-filled microbubbles were injected intravenously. The next step was to record the backscatter two-dimensional images at different systolic pressure and different contrasts, which synchronized with right ventricular pressure curve. Results The systolic pressure had significant effect on the differences of backscatter intensities (ED-ES) of sonicated albumin microbubbles and levovist (P<0.0001, P<0.02), but had little effect on that of perfluorocarbon-filled microbubbles (P=(0.10)). The correlation between systolic pressure and the ED-ES of sonicated albumin microbubbles was better than that of levovist (r=0.64, P<0.0001; r=0.57,P=0.001), and that of perfluorocarbon-filled microbubbles was the least (r=(0.41), P=0.07). Conclusion Pressure-sensitivity from contrast agent is subjected to the properties of the bubble shell and the inner gas. The sensitivity to the change of pressure from sonicated albumin microbubbles filled with air, encapsulating elastic shells, is better than that from levovist, but perfluorocarbon-filled microbubbles are insensitive to the change of pressure due to their rigid shells.更多还原