多普勒组织显像评估严重心力衰竭而QRS间期正常患者的左室收缩不同步

目的:应用多普勒组织显像(DTI)评估严重心衰而QRS间期正常的患者左室收缩不同步的发生率。方法:应用DTI分析20例QRS间期正常的严重心衰患者和20例正常人的左室侧壁、后间隔、前壁、下壁、前间隔及后壁的基底段和中段共12个节段的脉冲组织多普勒频谱,测量每例的QRS波起始至各个左室壁节段多普勒频谱收缩峰起始的时间(以Ts表示)。计算每例最大Ts与最小Ts的差值(Ts-MD)、Ts的标准差(Ts-SD)和Ts的变异系数(Ts-CV),用以评估两组对象左室收缩不同步的差异。结果:HF组的Ts-MD、Ts-SD和Ts-CV均较正常对照组明显增大(P<0.001),表明QRS间期正常的心衰患者存在左室壁收缩不同步。以TS-MD53.08 ms、Ts-SD18.08 ms和Ts-CV0.91(正常值单侧95%可信区间,x 1.65s)作为切断值,HF组左室收缩不同步的发生率分别为55.0%(11/20)、55.0%(11/20)和55.0%(11/20),显著高于对照组(P均<0.001);且QRS间期正常的心衰患者最大收缩延迟部位亦不完全相同。结论:DTI显示左室收缩不同步在严重心衰而QRS间期正常的患者中常见。这个结果支持心衰患者即使QRS间期正常也可能从CRT中受益。

Doppler Tissue Imaging Assessment of Left Ventricular Systolic Dyssynchrony in the Cases of Severe Heart Failure with a Normal QRS Duration

Objective:The aim of this study was to assess the prevalence of systolic dyssynchrony of the LV walls in patients of HF with a normal QRS duration by Doppler tissue imaging(DTI).Methods:Twenty patients with HF and a normal QRS duration as well as 20 healthy individuals were investigated with DTI to quantitatively analyze their pulsed-wave Doppler spectrum of basal and middle segments in six walls of left ventricle.The time between the onset of the QRS complex of the surface ECG and the onset of the systolic DTI wave were measured(Ts).Left ventricular contraction synchronization was assessed by the maximal difference(MD) in time to Ts,the standard deviation(SD)and the coefficient of variation(CV)of Ts in the 12 LV segments.Results:When a Ts-MD of > 53.08ms,Ts-SD of >18.08ms and a Ts-CV of > 0.91( 1.65 SD of normal controls) were used to define significant systolic desynchronize,the prevalence of systolic desynchronize was 55.0%,55.0% and 55.0%,respectively in HF patients group,which was significantly higher than that in normal control.The locations of delayed contraction of these patients were different.Conclusion:LV systolic dyssynchrony could be commonly demonstrated by DTI in patients of HF with a normal QRS duration.This finding will support the view about the possibility that more patients of HF may benefit from CRT.