儿童扩张型心肌病的心肌超声背向散射参数研究

The parameter study of myocardial ultrasonic backscattering in children with dilated cardiomyopathy

目的研究儿童扩张型心肌病心肌超声背向散射参数特点。方法采用超声背向散射积分技术，对20例扩张型心肌病（DCM）患儿及20例健康儿童，于左室长轴观采集室问隔中部及左室后壁心肌背向散射积分数据，包括校正平均背向散射积分（AⅡ％）和背向散射积分周期变化幅度（CVIB）。同时采集常规M型超声参数，并于心腔四腔观及五腔观，行脉冲多勒超声检查获得二尖瓣口和左室流出道血流图，计算左室Ri指数。结果与对照组比较，DCM组左室舒张末内径、收缩末内径、Tei指数、左室后壁AⅡ％增大（P〈0．01），室间隔、左室后壁CVIB减低（P〈0．01），背向散射积分曲线形态异常。DCM患儿心肌背向散射参数与左室Tei指数之间无相关性（P〉0．05）。结论扩张型心肌病儿童心肌背向散射参数变化特征：AⅡ％升高、CVIB下降、IBS曲线形态异常；左室Ri指数明显增高，心脏整体功能下降。

Objective To study the parameter features of myocardial ultrasonic integrated backscatter in children with dilated cardiomyopathy. Methods Twenty children with dilated cardiomyopathy （DCM） and 20 normal children as control group were enrolled in this study, the myocardial integral backscatter （IBS） parameters of the intermedial segment in both interventricular septum （IVS） and the left ventricular posteriorwall （LVPW） were obtained based on the parastemal long - axis view of left ventricle, the ultrasonic integrated backscatter parameters included calibrated average image intensity （AⅡ%） and cyclic variation of integrated backscatter （CVIB）. M - mode and PW- mode parameters were calculated at the same time. The rheograms of mitral orifice and left ventrieular outflow were examined on the four chambers view and five chambers view by pulse Doppler ultrasound, then Tel index of left ventricle was calculated. Results Compared with control group, the Tel index of left ventricle and AⅡ% of LVPW in DCM group was increased （ P 〈 0.01 ）, CVIB in LVPW and IVS was decreased （ P 〈 0.01 ） in children with DCM, and the IBS curve was abnormal. There was no co, relation between integrated backscatter parameters and Tel index of left ventricle in children with DCM （ P 〉 0. 05 ）. Conclusion The characteristics of children with dilated cardiomyopathy include increased AⅡ%, reduced CVIB and abnormal IBS curve, and Tel index of left ventricular is increased obviously, the cardiac function is decreased.