应用速度向量成像技术研究正常左心室壁加速度

Study on myocardial acceleration of the normal left ventricular wall by velocity vector imaging

目的尝试应用速度向量成像（velocity vector imaging，VVI）技术研究正常左心室壁加速度特点。方法50例健康志愿者，应用VVI技术检测左室16个节段运动速度，应用研制的软件获得加速度一时间曲线。分析左室壁加速度分布特点。结果同一室壁收缩早期正向峰值加速度（ACCs）和舒张早期负向峰值加速度（ACCd）表现为基底部〉中部〉心尖部（均P〈0．05），同一水平各室壁之间ACCs和ACCd差异均无统计学意义（均P〉0．05），同一节段ACCd显著大于ACCs（均P〈0．05）。结论VVI技术可研究室壁加速度特点，为进一步检测病变心肌加速度的变化提供正常依据。

Objective To investigate the characteristics of myocardial acceleration （ACC） in normal left ventricle （LV） by velocity vector imaging （VVI）. Methods The myocardial velocities of sixteen LV wall segments in fifty normal volunteers were detected by VVI. Segmental myocardial ACC was calculated by using special software and the distribution of ACC in LV wall was analyzed. Results There were significant differences among the levels of LV in the early systolic peak ACC （ACCs） and early diastolic peak ACC （ACCd）, and both of ACCs and ACCd increased from apex to base in the same LV wall （all P〈0.05）. However, there were no significant differences among six LV walls at the same level in ACCs and ACCd （all P〉0.05）. In the same segment, ACCd was significantly higher than ACCs （all P〈0.05）. Conclusions Myocardial ACC can be detected by VVI, which is the basis for further investigation of ACC in the diseased myocardium.