心腔内组织速度图模式对心肌异位兴奋显像的实验研究

Intracardiac tissue velocity imaging for detecting myocardial excitation and conduction： an experimental study

目的：评价心腔内组织多普勒速度图（TVI）模式对心肌异常激动及传导的显像功能。方法：10只开胸犬心室起搏，采用心腔内TVI模式，观察室性心律时室壁的速度分布变化。结果：对照心电图，心腔内TVI模式可检测到心室起搏时室壁最早出现的收缩运动，该区域与起搏电极放置部位相一致；并可在随后的心室起搏波过程内观察到该处收缩运动的扩散。结论：心腔内TVI技术能够实时显示与心肌电活动密切相关的机械运动，从而使观察心肌兴奋的发生和传导成为可能。

Objective To evaluate the value of intracardiac tissue velocity imaging （TVI） for showing the myocardial excitation and conduction. Methods Open-chest models of 10 dogs underwent intracardiac ultrasound catheter examination with TVI imaging during cardioventricular pacing. Results The myocardial velocity maps detected that the domain contract firstly was just the same position where the pacing electrode located, and the velocity distribution which represented myocardium contraction had propagated when the pacing wave occurred. Conclusions The intracardiac TVI can show the onset and propagation of myocardial electric activity and velocity change which is in response to the mechanical activity synchronously in real-time. This technique may provide a new way for observing the occurrence and sequence of excitation.