心脏运动对血流速度时间积分测定影响的模拟实验研究

目的 探讨体外模拟心脏运动对多普勒血流流速曲线速度时间积分(VTI)测定的影响。方法用自行设计的TD-3型心底运动模拟仪和血流模拟器，记录两者在不同速度状态下分别运动和同步运动时多普勒流速曲线的特点．观察模拟心脏运动对模拟血流流速曲线VTI测定的影响及其定量关系。结果在模拟心脏运动作用下，模拟血流改变了原有的流速曲线波形，两者同向运动时，模拟血流流速曲线VTI为两者单独运动时的VTI之和．反向运动时为两者单独运动的VTI之差．而模拟心腔运动所产生的多普勒频移信号的速度和频率没有变化。结论模拟心脏运动对模拟血流流速曲线VTI测值有明显影响，在用多普勒方法测量血流量时应当考虑到心脏运动对多普勒测值的影响并加以校正。

Influence of cardiac motion on the velocity-time integrals of Doppler flow spectra:in vitro model study

Objective To investigate the influence of simulated heart motion on the Doppler spectrum velocity- time integral (VTI) of simulated blood flow measurements through an in vitro model. Methods Using heart-motion simulator model TD-3 designed by ourselves to note the feature of Doppler spectrum of simulated heart and simulated blood flow which moved separately and synchronously.The affection of the simulated heart's motion on the VTI of the simulated blood flow and their quantitative relationship were observed.Results When the simulated heart and blood flow moved synchronously, the VTI of the combined motion was the algebra sum of their VTI when their motion independently. The velocity and frequency of Doppler spectrum of simulated heart were unchanged. Conclusions The motion of simulated heart has a great influence on the value of Doppler blood flow spectrum VTI and this effect should be considered when blood flow volume was measured using Doppler's methods.