多普勒组织成像对正常人左室功能分析

目的：本文应用多普勒组织成像（DTI）脉冲技术检测正常人左室局部运动功能，并将DTI测得局部舒张速度与左室整体舒张功能检测方法行相关性分析。方法：经心尖显示左心长轴切面，运用多普勒技术获取舒张期二尖瓣血流频谱，测量E峰和A峰速度，转换DTI速度图模式，将取样容积分别放置左室中部乳头肌水平的前间值速度。结果：左室后壁收缩和舒张速度均高于前间壁测值，两者之间存在显著性差异，按年龄分级对比发现：收缩期峰值速度在不同年龄组无显著性差异。但舒张早期速度和舒张晚期速度在不同年龄组间比较均有显著性差异。年龄瑟DTI测值相关性分析表明：随着年龄增加，舒张早期和晚期峰值速度比值（VE/VA)变小。结论：随着年龄增大，正常人室壁主动松弛功能减低，心肌顺应性下降，舒张早期充盈减少。DTI能定量测定室壁运动速度，可更精确反映收缩和舒张功能变化。

ASSESSMENT OF REGIONAL LEFT VENTRICULAR CONTRACTION AND RELAXATION FUNCTION BY PULSED DOPPLER TISSUE IMAGING IN NORMAL SUBJECTS

The aim of this study was to examine the clinical application of pulsed Doppler tissue imaging (DTI) for assessing left ventricular contraction and relaxation function in normal subjects at different age. Methods: Each examination consisted of pulsed wave Doppler blood flow and pulsed Doppler tissue imaging measurements. A sample volume was set at the mitral valve orifice in the long - axis view of the left ventricle from the cardiac apex. Early - diastolic and late - diastolic peak velocities of pulsed Doppler blood flow were measured. At the same view, sample volumes were set at the endocardial portion of the papillary muscle level of anteroseptal and posterior wall by pulsed Doppler tissue imaing. The peak velocities of systolic ( Vs). early - diastolic (VE ) and late - diastolic (VA) wave were measured. Results Vs , VE and VA of posterior wall in left ventricle were higher than those of anteroseptum. The difference of the systolic peak velocities at different age was not significant. But the early - diastolic and late - diastolic peak velocities were significantly different. The correlation between results obtained from DTI measurements and age showed that with increasing age. the VFVA decreases. Conclusions: These results demonstrated that with increasing ages, the rapid ventricular filling significantly decreases. DTI could accurately present myocardial wall contraction and relaxation function.