定量组织速度及应变率显像对健康犬心肌运动特征的评价

Quantitative tissue velocity and strain rate imaging in the evaluation of normal canine myocardium

目的探讨定量组织速度及应变率显像评价犬心肌运动的可行性及正常健康犬心肌各节段的运动特征。方法采集 18只健康杂种犬心肌各节段长轴TVI图像 ,分别对心肌定量组织多普勒速度及应变率曲线进行分析。结果健康犬心肌各节段定量组织速度曲线显示收缩期可见一正向波 (S波 ) ,舒张期可见两负向波 (E、A波 ) ,波峰清晰 ,紧邻S波及E波前分别可见等容收缩波及等容舒张波 ,从基底部到心尖部同一波峰时序基本一致 ,波幅依次递减 ;应变率曲线显示 :以上心动周期各波峰均清晰可见 ,但收缩期呈负向波 ,舒张期呈正向 ,从基底部到心尖部波幅基本一致。结论定量组织速度及应变率显像均能准确显示心肌各节段运动特征 ,但两者曲线意义不同。

Objective To explore the feasibility of quantitative tissue velocity and strain rate imaging in the evaluation of normal canine myocardial motion and the characteristics of the curve which displayed the motion of different myocardial segments.Method TVI imaging was acquired in 18 healthy mongrel dogs and the velocity and strain rate imaging curve was analyzed. ResultIn the velocity curve, one positive S wave and two negative waves (E and A) were displayed distinctly during the systole and fast filling period and late diastole respectively. Just before S and E, there was one wave formed during the isovolumic contraction and isovolumic relaxation period respectively. The corresponding waves in different segments were simultaneously but attenuated in magnitude from base to apical segments. The above waves could also be found in the strain rate curve but the directions of the waves were contrary to those above mentioned. The magnitude of the strain rate curve was alike in different segments. Conclusion Both of the velocity and strain rate curve are capable of displaying the motion characteristics of different segments whereas the two modalities have different meanings.