定量组织速度成像评价二尖瓣置换术后左心功能的临床研究

Assessment of left ventricular function in patients with mitrai valve replacement by quantitative tissue velocity imaging

目的探讨定量组织速度成像（QTVI）评价二尖瓣置换术（MVR）后左室整体和局部功能的临床价值。方法80例MVR术后患者作为病例组，根据心律分为窦性心律组40例和心房颤动（房颤）组40例。常规超声心动图检查后采集心尖四腔观、心尖两腔观、心尖左室长轴观的组织多普勒动态图像，启动QTVI模式，绘制左室各壁瓣环、心肌节段的时间一速度曲线。测量收缩期峰值速度（Sa、Sm）和快速舒张期峰值速度（Ea、Em）等。结果①与正常组比较，MVR组6个壁二尖瓣环和各心肌节段Sa、Sm和Ea、Em均明显减低（P〈0．001）；②二尖瓣环收缩期平均峰值速度（Sa’）与左室射血分数（LVEF）呈正相关（P〈0．001）；③二尖瓣环快速舒张期平均峰值速度（Ea’）与等容舒张期时间均值（IVRT＇）呈负相关（P〈0．01）。结论QTVI能够评价MVR术后左室整体和局部的收缩与舒张功能，具有重要的临床价值。

Objective To evaluate the clinical value of quantitative tissue velocity imaging （QTVI） in assessing left ventricular （LV） global and regional myocardial function in patients with mitral valve replacement（MVR）. Methods Eighty patients having their implantations for more than six months were examined by echocardiography. QTVI-derived parameters such as peak systolic velocity（Sa, Sin） and early diastolic velocity（Ea, Em） of mitral annulus and LV wall were measured from the apical four chamber, two- chamber and long axis views. Results ①As expected, mitral annular Sa and Ea were significantly lower in MVR groups compared with controls（ P 〈0. 001 ）. ②Compared with controls, Sm and Em of corresponding myocardial segments in MVR groups decreased significantly（ P 〈0. 001）. ③There was significant positive correlation between Sa＇ and LV ejection fraction but negative correlation between Ea＇ and isovolumie relaxation time（IVRT＇） in patients（ P 〈0.01）. Conclusions QTVI plays an important role in determining LV function of patients after MVR accurately.