实时三维超声心动图定量评价心肌梗死后心力衰竭患者左心室收缩不同步性及其意义

Quantitative evaluation of the left ventricular systolic dyssynchrony and its significance in patients with heart failure after myocardial infarction by real-time three-dimensional echocardiography

目的 应用实时三维超声心动图（RT-3DE）定量评价心肌梗死后不同程度心力衰竭患者左室收缩不同步性,并初步探讨收缩不同步指数（SDI）评价左室不同步的临床价值.方法 40例心肌梗死后心力衰竭患者（心肌梗死组）和30例健康体检者（正常对照组）作为研究对象.心肌梗死组分为A、B两个亚组：心功能重度减低组[左室射血分数（LVEF）≤35%]和轻度减低组（35%＜LVEF＜50%）,对其进行左室17节段实时三维时间、容积分析,探讨SDI界定不同步的截断值及SDI与收缩功能指标LVEF之间的相关性,并与正常组对照.结果 心肌梗死组SDI显著高于正常对照组（P＜0.01）,A组SDI显著高于B组（P＜0.01）,SDI与LVEF呈负相关（r=-0.84,P＜0.01）;以SDI大于正常组99%单侧上限界值定义为左室收缩不同步,心肌梗死组不同步率为85%,其中A组为100%,B组为75%.结论 心肌梗死后心力衰竭患者普遍存在左室收缩不同步,且不同步程度与收缩功能呈负相关.SDI能敏感地发现左室不同步,RT-3DE在评价心肌梗死后左室收缩不同步性方面有其独特优势.

Objective To quantitatively assess the left ventricular systolic dyssynchrony in patients with varied degrees of chronic congestive heart failure after old myocardial infarction（OMI） by real-time three-dimensional echocardiography（RT-3DE） and investigate the clinical value of the systolic dyssynchrony index（SDI）. Methods Forty patients with congestive heart failure after OMI （infarction group） were divided into the severe dysfunction group （LVEF ≤35 %） and the mild dysfunction group （35 % 〈 LVEF〈50%） ,and 30 normal subjects served as the control. RT-3DE was performed on all subjects to obtain the 17-segmental time-volumetric curves and global systolic function. SDI changes in above groups and the correlation between SDI and LVEF were analyzed. Results The SDI of the infarction group was significantly higher than that of the normal control group （ P 〈0. 01 ）. The SDI of the severe dysfunction group was significantly higher than that of the mild group （P〈0.01）. SDI and LVEF were negatively correlated （ r = -0.84, P 〈0. 01 ）. The dyssynchrony rate in the infarction group was 85 %,in the severe dysfunction group was 100%, in the mild group was 75%. Conclusions Left ventricular systolic dyssynchrony is prevalent in patients with OMI, and it is negatively correlated with the LVEF. SDI is a sensitive indicator in assessing left ventricular systolic dyssynchrony. RT-3DE has a unique advantage in the evaluation of the left ventricular systolic dyssynchrony,especially in the patients with myocardial infarction.