应用实时三维超声心动图评价不同程度左室射血分数减低者的左室收缩同步性

Real-time three-dimensional echocardiographic assessment of left ventricular dyssynchrony in patients with different degree of LVEF decrease

目的应用实时三维超声心动图分析左室不同步性在不同程度左室射血分数(LVEF)减低者中的发生率。方法对64例LVEF减低者的实时三维超声心动图时间-容积进行比较分析,其中LVEF<30%者35例,30%≤LVEF<45%者29例。以收缩期不同步化指数(SDI)>8.3%作为室内收缩不同步的指标。结果30%≤LVEF<45%者中有20.7%存在收缩不同步,而LVEF<30%者中不同步比例高达63.9%,二者差异有统计学意义(P<0.01)。16节段、12节段(中间段和基底段)和6节段(基底段)最小收缩容积点时间的标准差和最大差值差异有统计学意义,P均<0.01。30%≤LVEF<45%者平均收缩期不同步化指数为(6.4-2.3)%,LVEF<30%患者为(4.5-6.5)%(P<0.001)。收缩期不同步化指数与左室收缩功能有良好的相关性,与左室射血分数相关系数r=-0.493,P<0.001,与QRS间期不相关。结论尽管30%≤LVEF<45%者的左室收缩同步比例很高,但仍有一定比例的患者存在收缩不同步。同时,亦有一定比例的LVEF<30%者同步性尚好。

Objective To evaluate the prevalence of dyssynchrony in patients with different degree of LVEF decrease using real-time three-dimensional echocardiographic technique. Methods The results of regional volume curves in sixty-four patients with different degree of LVEF decrease （35 with LVEF〈30%, 29 with 30%≤LVEF〈45%） were analyzed and compared on RT3DE. The mean systolic dyssynchrony index （SDI） of more than 8. 3 % was considered a marker of intraventricular dyssynchrony. Results Dyssynchrony was observed in 6 （20.7%） patients with 30%≤LVEF〈 45% versus 23 （63.9 % ） patients LVEF〈30 %, and a significant difference was found between the prevalence of dyssynchrony derived from echo criteria in two groups （P〈0.01）. There were remarkably difference in standard deviation （SD） and maximal difference （Dif） of the time to point with minimal systolic volume （Tmsv） of 16 segments, 12 segments （6 mid and 6 basal）and 6 segments （basal） in two groups, P〈0. 05. The mean systolic dyssynchrony index （SDI） in patients with 30%≤LVEF〈45% and those with LVEF〈30% were 6.4%--2.3% vs 14.5%--6.5%（P〈0. 001）, respectively. Significant correlations was present between SDI and left ventricular systolic function （r= - 0. 493, P〈0. 001）. No significant correlations was found between SDI and QRS duration. Conclusion Although patients with 30%≤LVEF〈45% had a high prevalence of cardiac synchronicity, yet some still had dyssynchrony. Moreover, good cardiac synchronicity also existed in a small percentage of patients with LVEF〈30%.