超声二维斑点追踪评价二尖瓣置换术后左心室短轴心肌径向运动的研究

目的 应用斑点追踪技术研究二尖瓣置换术后左心室短轴心肌径向应变变化规律,探讨二尖瓣置换术对左心室短轴径向运动的影响.方法 35例二尖瓣置换术患者（MVR组）和20例正常人（对照组）,经胸采集左心室短轴二尖瓣水平、乳头肌水平和心尖水平二维图像,利用斑点追踪显像技术测算各平面不同节段心肌径向收缩期峰值应变（RS）.结果 MVR组术前二尖瓣水平各节段心肌RS较正常组减低,乳头肌水平及心尖水平大部分节段心肌RS较正常组增高（P＜0.05）；MVR组术后2周二尖瓣水平各节段心肌RS较术前组减低,乳头肌水平及心尖水平大部分节段心肌RS较术前组减低,部分节段较正常组减低（P＜0.05）；MVR组术后1年二尖瓣水平及乳头肌水平各节段心肌RS均显著增加,显著高于术后2周组（P＜0.05）,心尖水平大部分节段心肌RS与正常组及术后2周组无明显差异（P＞0.05）.结论 MVR组术后早期左心室短轴心肌径向应变减低,MVR组术后1年左心室短轴心肌径向应变显著改善；人工机械瓣对二尖瓣环局部的心肌运动有一定的影响.

Evaluation of left ventricular radial systolic function after mitral valve replacement by using two-dimensional speckle tracking imaging echocardiography

Objective To investigate the influence of mitral valve replacement （MVR）on left ventricular （LV） radial systolic function by using two-dimensional speckle tracking imaging（2D-STI）.Methods 35 patients undergoing MVR were studied before and after operation,and 20 healthy volunteers were chosen as controls.Two dimensional images were recorded from the LV short-axis view at the levels of mitral valve （MV）,papillary muscles （PM） and apical level（AP）.The peak systolic radial strains （RS）of six segments were measured by using 2D-STI.Results The peak RS of six segments at MV level before MVR were lower than those in the control group,but the peak RS at PM and AP levels were mostly higher than those in the control group （P 〈 0.05）.The peak RS at three levels after 2 weeks of MVR were lower than those before MVR（P 〈0.05）.The peak RS at MV level after 1 year of MVR were higher than those before MVR and 2 weeks after MVR（P 〈 0.05）.There was no significant difference among the normal group,2 weeks after MVR group and 1 year after MVR group for most of the peak RS at AP level （P 〉 0.05）.Conclusions The peak RS of the LV right after MVR often decreases,but it improves significantly after 1 year of MVR.MVR has some effects on the radial systolic function of the LV at MV level.