二维斑点追踪成像技术评价左室心肌节段舒张功能的研究

目的：斑点追踪成像技术(Speckle tracking imaging, STI)分析不同舒张功能状态下左室节段心肌的应变率，比较心肌节段舒张功能与整体舒张功能的关系。 方法：Doppler测量二尖瓣口血流E峰、A峰，TDI测量二尖瓣环室间隔eSp峰、侧壁eL峰。将所有病例分为三组：A组：舒张功能正常组；B组：顺应性减低；C组：假性正常化组。用STI分析左室17个节段心肌舒张早期应变率(ESR)、舒张晚期应变率(ASR)，比较各组间17节段心肌舒张期应变率的变化规律。 结果：随着整体舒张功能的降低，17个节段心肌的ESR也相应降低，ASR则增大，二尖瓣环水平后间隔基底段的变化幅度大于前侧壁基底段。与A组相比，B组和C组中间段心肌与心尖段心肌ESR的变化幅度均大于基底段；B、C两组相比，心尖段心肌ESR的变化幅度最大，基底段和中间段变化不明显。 结论：STI有助于早期发现节段心肌的舒张功能受损；随着舒张功能恶化，心尖段ESR持续减低，ASR先升高后降低。

To evaluation the left ventricular segment diastolic function by speckle tracking imaging

Objective To evaluate the strain rate of left ventricular segment myocardium in different diastolic function by Speckle Tracking Imaging(STI), and to compare the relationship between segment diastolic function and integral diastolic function. Methods Mitral valve flow E peak and A peak were measured by Doppler, mitral annulus eSp peak in ventricular septum and eL peak in lateral wall were acquired. All patients were divided to three groups: Group A: Left ventricular diastolic function is normal; Group B: Left ventricular compliance is reduced; Group C: Left ventricular diastolic function is pseudo normalization. To analyze the early/late strain rate(ESR and ASR) of myocardial relaxation in each segment by STI. Results With the decrease of integral diastolic function, the ESR in each segment also was decreased, but the ASR in each segment was increased. Analyse the change of ESR and ASR in three groups, the amplitude of the middle segments and apical segments is larger than that of the basal segments. Within group B and group C, the maximal change of ESR and ASR is apical myocardium. Conclusions STI is helpful for early detection of diastolic dysfunction in segmental myocardium; With diastolic dysfunction, apical ESR continued to decrease, ASR increase first and then decrease.