实时三维超声心动图评价慢性心力衰竭患者左心室同步性及其与收缩功能的关系

摘要

Objective To compare left ventricular systolic dyssynchrony between healthy individuals and heart failure patients with severe damage in cardiac function with real-time three-dimensional echocardiography (RT-3DE), and to analyze the relationship between mechanical dyssynchrony and left ventricular systolic function. Methods Twenty heart failure patients (case group) and 22 healthy volunteers (control group) were enrolled in this study, and full volume images were acquired using RT-3DE. The time to minimal systolic volume (Tmsv) of each segment was measured in time-volume curve derived with Qlab software. The standard deviation (Tmsv-SD) and the maximal difference (Tmsv-Dif) of Tmsv were calculated for basal level, mid level, apical level, 12 segments and 16 segments, respectively. Dyssynchrony parameters of 12 segments and 16 segments standardized by heart rate (Tmsv-SD% and Tmsv-Dif%) were automatically calculated by Qlab. All parameters were compared between the two groups, and correlation between 3D-left ventricular ejection fraction (3D-LVEF) and dyssynchrony parameters were evaluated respectively in case group. Results Dyssynchrony parameters of 3 levels, 12 segments and 16 segments in case group were remarkably higher than those in control group (all P<0. 01).The 3D-LVEF correlated closely with all dyssynchrony parameters in case group (r= -0. 511--0. 839, all P<0. 01) ,and 16 segments parameters showed the strongest correlation. Parameters standardized by heart rate correlated more strongly with 3D-LVEF than non-standarized ones (r= -0. 730-0. 839 vs r=-0. 626--0. 683). Conclusion Mechanical dyssynchrony exist in the global and each level of left ventricle in chronic heart failure patients whose cardiac function have been damaged severely. RT-3DE is a feasible tool for quantifying left ventricular mechanical dyssnchrony.%目的 利用实时三维超声心动图(RT-3DE)比较心功能严重损害的慢性心力衰竭(CHF)患者与正常人左心室收缩同步性的差异,分析左心室收缩同步性与收缩功能的关系.方法 研究对象为CHF患者20例(病例组)和正常人22名(对照组).采集所有入选者的全容积三维图像.用QLab软件获取左心室时间-容积曲线,测量左心室各个节段自心电图Q波起点至收缩期最小容积时间(Tmsv),推算左心室3个短轴水平(二尖瓣水平、乳头肌水平和心尖水平)、12节段和16节段同步性参数:达收缩期最小容积时间标准差(Tmsv-SD)和最大时间差(Tmsv-Dif).系统自动计算出12节段和16节段以心率标化的参数( Tmsv-SD％、Tmsv-Dif％).比较两组各同步性参数,并分析病例组由RT-3DE所测左心室射血分数与各参数的相关性.结果 与对照组比较,病例组左心室3个短轴水平、12节段及16节段同步性参数均显著增大(P均＜0.01).病例组左心室射血分数与左心室3个短轴水平、12节段、16节段同步性参数均呈显著线性负相关(r＝-0.511～0.839,P均＜0.01),16节段参数相关性最高,标化的同步性参数相关性均高于非标化参数(r＝一0.730～-0.839 vs r＝-0.626～0.683).结论 RT-3DE能定量评价室壁机械运动同步性.心功能严重损害的CHF患者左心室内存在机械运动不同步,将进一步降低左心室射血分数.