动脉粥样硬化兔左心室超声背向散射参数与心肌纤维化关系的对比研究

目的应用声学密度定量(Acoustic Densitometry,AD)技术检测动脉粥样硬化(Atherosclero-sis,AS)后左室心肌超声背向散射参数的变化,并与其心脏的纤维化改变进行对比研究,以确定两者是否具有相关性。方法在建立AS兔模型的基础上,应用AD技术测定AS兔和正常对照组兔左室相应部位心肌密度值,同时应用免疫组化检测AS兔心肌纤维化的病变程度,并对AS兔的心肌密度值与纤维化程度进行比较及相关分析。结果AS组室间隔中部(IVS)、左室前壁(LVAW)和左室后壁(LVPW)AAI(Average Image Intensity)明显高于正常对照组(P<0.05);AS兔的左室心肌I型和III型胶原纤维蛋白的表达水平显著高于正常兔心肌细胞间质I型和III型胶原纤维蛋白的表达,而且AS组左室前壁心肌AII值的改变与心肌纤维化的程度大致成正相关,r=0.4206。结论心肌背向散射是一种较有价值的无创评估心肌纤维化程度的检测手段,从而间接评价左室舒张功能。

Study on the Changes of Acoustic Densitometry and Correlated Myocardial Fibrosis in Left Ventricle with Atherosclerosis

Objective To use acoustic densitometry(AD)techenique to detect the correlation of myocardial ultrasonic backscatter and fibrosis of left ventricle secondary to atherosclerosis (As). Methods On the basis of establishing rabbit model of atherosclerosis, we compared myocardial ultrasonic backscatter parameters of left ventricle secondary to atherosclerosis with normal control group using acoustic densitometry technique. The degree of myocardial fibrosis was measured with immunohischemistry methods. Results In AS group,expression of I and III type collagen was increased. The values of AII myocardial of left ventricular secondary to atherosclerosis were higher than normal. The AII of left ventricular anterior wall was correlated significantly with left ventricular myocardial fibrosis(r =0.4206,p<0.01). Conclusion Ultrasonic backscatter was useful in determining myocardial fibrosis of left ventricular secondary to atherosclerosis .It is an objective, simple and indirect technique for evaluating diastolic dysfunction of left ventricle.