速度向量成像技术评价正常QRS波群心力衰竭患者左心室收缩同步性的初步临床研究

Assessment of left ventricular systolic synchrony in patients with chronic heart failure and normal QRS duration by velocity vector imaging

目的 探讨速度向量成像（VVI）技术评估正常QRS波群慢性心力衰竭（CHF）患者左室心肌收缩同步性的应用价值。方法 QRS≤120ms CHF患者和健康志愿者各30例，常规测量左室舒张末期内径（LVDd）、舒张末期容积（LVEDV）、收缩末期容积（LVESV）和射血分数（LVEF）。在系列心尖长轴及胸骨旁短轴观上，VVI成像显示所有受试者的左室速度向量图。心尖长轴观测量各节段收缩期纵向速度达峰时间（Tvl）和纵向应变达峰时间（Tsl），胸骨旁短轴观测量收缩期径向速度达峰时间（Tvr）和环向应变达峰时间（Tsc），计算节段达峰时间的标准差（Tvl—SD，Tsl—SD，Tvr-SD，Tsc-SD）及任意两节段间最大达峰时间差值（Tvl—diff，Tsl-diff，Tvr-diff，Tsc—diff）。结果 与对照组相比，CHF组LVDd，LVESV，LVEDV均显著增加（P〈0．05或0．01），LVEF显著降低（P〈0．01）。左室心肌收缩不同步指标Tvl—SD，Tsl—SD，Tvr—SD，Tsc-SD及Tvl—diff，Tsl-diff，Tvr-diff，Tsc-diff均显著增加（P〈0．01）。结论 QRS波群正常的CHF患者左室心肌在纵向、径向与环向上均存在显著的收缩不同步。VVI技术可准确评价CHF患者左室心肌收缩的同步性。

Objective To assess the longitudinal,radial and circumferential systolic synchrony of the left ventricular（LV） by velocity vector imaging （VVI） in patients with chronic heart failure（CHF） and normal QRS duration. Methods Thirty patients with CHF and QRS duration ≤120 ms（CHF group） and 30 healthy subjects（control group） were enrolled in this study. LV end-diastolic dimension（LVDd）, LV end-systolic volume（LVESV）, LV end-diastolic volume （LVEDV） and LV ejection fraction （LVEF） were measured using two-dimensional echocardiography. VVI was done in all three standard LV apical views and parasternal LV short axis（SAX） views. According to 16 segments analysis method,the time to peak systolic longitudinal velocity（Tvl） and peak systolic longitudinal strain（Tsl） in the LV apical views and the time to peak systolic radial velocity（Tvr） and peak systolic circumferential strain（Tsc） in the LV SAX views were measured by VVI. The standard deviation of Tvl,Tsl,Tvr,and Tvc （TvI-SD,TsI-SD,Tvr-SD and Tsc-SD） and the maximal temporal difference of Tvl, Tsl, Tvr, and Tsc （Tvl-diff, Tsl-diff, Tvr-diff and Tsc-diff） of 16 segments were used as an indicator of systolic dyssynchrony. Results Compared with the values in the control group,the LVDd, LVESV and LVEDV increased significantly（ P d0.05 or 0.01） and the LVEF decreased significantly（ P 〈0. 01） in the CHF group. TvI-SD,TsI-SD,Tvr-SD,Tsc-SD,Tvl- diff,Tsl- dill, Tvr-diff and Tsc-diff were significantly higher in the CHF group than those in the control group （all 〈 0. 01）. Conclusions The longitudinal, radial and circumferential systolic dyssynchrony of the LV were commonly existed in patients with CHF and normal QRS duration. VVI is a useful modality to evaluate the systolic synchrony of the LV in patients with CHF.