中文摘要：

目的应用实时三维超声心动图心室节段收缩非同步指数（regional systolic dyssynchrony index，R-SDI）定量评估慢性心功能不全患者左室机械收缩非同步运动价值，并探讨R-SDI与收缩功能间的关系。方法42例慢性心功能不全（LVEF〈50％）患者，根据左室射血分数（LVEF）不同分为两亚组：心功能中．重度降低组（A组：LVEF〈40％）、轻度降低组（B组：LVEF≥40％）。另选择33例健康志愿者作正常对照组（C组：LVEF〉50％）。分别获取实时三维超声图像并描绘左室容积．时间曲线，计算出左室16节段、12节段及6节段非同步指数SDI（16R-SDI、12R-SDI、6R．SDI），探讨16R-SDI、12R—SDI、6R-SDI诊断左室收缩非同步运动的价值及其与收缩功能（LvEF）的相关洼。结果慢性心功能不全组R-SDI显著高于正常对照组（P〈0．01），慢性心功能不全A组R-SDI明显大于B组（P〈0．01），16R．SDI、12R-SDI、6R—SDI与LVEF呈负相关（F．0．843，r=0．840，r=-0．841，均P〈0．01）。结论心室节段收缩非同步指数可作为定量评价左室机械收缩非同步运动的有效指标，非同步运动程度与心室收缩功能呈负相关。实时三维超声心动图可用于定量评价慢性心功能不全患者左心室非同步运动。

英文摘要：

Objective To quantitatively assess the left ventricular systolic dyssynchrony in patients with chronic heart failure based on the regional systolic dyssynchrony index （R-SDI） derived from real-time three-dimensional echocardiography （RT-3DE）, and investigate the relation between R-SDI and the left ventricular systolic function. Methods Forty-two patients with chronic heart failure （LVEF〈50%） were classified into severe dysfianction group （group A, LVEF〈40% ） and mild dysfunction group （group B, LVEF ≥40%）, with 33 healthy subjects as the control group （LVEF〉50%）. RT-3DE was performed for each subject to obtain the left volume-time curves and the 16, 12, and 6 segment R-SDI. The value of R-SDI in assessing left ventricular systolic dyssynchrony and its correlation with LVEF were analyzed. Results The 16, 12, and 6R-SDI were significantly higher in the chronic heart failure group than in the control group （P〈0.01）. The R-SDI of group A was significantly greater than those of group B in the chronic heart failure patients （P〈0.01）, and 16R-SDL 12R-SDI, and 6R-SDI were inversely correlated with LVEF of the patients （r=-0.843, -0.840, and -0.841, respectivel, P〈0.01）. Conclusion R-SDI can be used to assess the left ventricular mechanic systolic dyssynchrony, and the degree of the dyssynchorony is inversely correlated with LVEF. RT-3DE can serve as a valuable modality for quantitative evaluation of left ventricular dyssynchrony in chronic heart failure patients.