负荷组织多普勒和斑点追踪法预测心脏再同步化治疗的响应

Dyssynchrony by Tissue Doppler Imaging and Speckle-tracking Approach of Stress Echocardiography and Response to Cardiac Resynchronization Therapy

目的利用组织多普勒成像(TDI)和斑点追踪法(STI)检测心力衰竭患者心室的同步性,比较静息超声和负荷超声试验评价心脏再同步化治疗(CRT)的效果。资料与方法心力衰竭患者35例拟行CRT术,CRT术前利用TDI和STI检测左心室的同步性,TDI测量左心室12节段组织多普勒曲线的电机械延迟时间(EMD),STI测量左心室短轴前间隔与后壁径向应变(RS)和四腔心切面各个节段横向应变峰值延迟最大时间差值(TS),分别在静息超声和负荷超声心动图试验下测量;CRT术后复查超声心动图检测心力衰竭患者的CRT响应。结果 35例患者CRT植入22例(63%)存在响应,CRT响应组与CRT无响应组比较:静息超声TDI测量的EMD分别为(83±32)ms与(60±26)ms(t=2.113,P<0.05),STI测量的RS分别为(207±78)ms与(151±61)ms(t=2.216,P<0.05),TS分别为(213±81)ms与(163±60)ms(t=2.091,P<0.05);负荷超声试验后EMD分别为(91±29)ms与(56±26)ms(t=3.527,P<0.01),RS分别为(228±71)ms与(144±61)ms(t=3.556,P<0.01),TS分别为(231±75)ms与(154±62)ms(t=3.287,P<0.01)。结论 TDI和STI能够检测左心室内的同步性,负荷超声检测的同步性参数是预测心力衰竭患者CRT响应的有效指标,优于静息状态下的参数。

Purpose Cardiac resynchronization therapy（CRT） improves functional capacity and survival in heart failure.Tissue Doppler imaging（TDI） and speckle tracking image（STI） can predict response to CRT for heart failure patients.The aim of this study is to evaluate whether exercise dyssynchrony by TDI and STI could select responders to CRT.Materials and Methods Thirty-five patients were enrolled and scheduled for CRT implantation performed dobutamine stress echocardiography（DSE）.TDI and STI were used to measure synchronism of left ventricular.Pulsed TDI was acquired using two-,three-and four-chamber apical views to assess the longitudinal movement of the left ventricle.Each segmental electromechanical delay（EMD） was defined as the time from the onset of the QRS to the peak of the systolic（S） TDI wave.Also rest left ventricular dyssynchrony was evaluated by two speckle tracking strain methods：radial from midventricular short-axis views and transverse from an apical four-chamber view.Radial dyssynchrony was defined as a time difference between the anteroseptal and posterior wall segmental peak strain and transverse dyssynchrony was defined as maximum opposing wall delay in time-to-peak strain among the three apical views from basal and mid-levels considered as significant dyssynchrony.DSE was performed to determine stress dyssynchrony for the patients before pacing implantation.Follow-up echocardiography was performed after CRT for response to CRT.Results During the follow-up period after CRT,22 patients（63%） were responders.Intraventricular dyssynchrony data between the responder and nonresponder groups were compared as follows：（83±32） ms vs.（60±26） ms（t=2.113,P〈0.05） in EMD measured by TDI,（207±78） ms vs.（151±61） ms（t=2.216,P〈0.05） in opposing wall delay of short-axis radial strain（RS） and（213±81） ms vs.（163±60） ms（t=2.091,P〈0.05） in opposing wall delay of transverse strain（TS） from apical views at rest;（91±29） ms vs.（56±26） ms（t=3.527,P〈0.01） in EMD,（228±71） ms vs.（144±61） ms（t=3.556,P〈0.01） in RS and（231±75） ms vs.（154±62） ms（t=3.287,P〈0.01） in TS at stress.Conclusion Intraventricular dyssynchrony assessed by stress TDI and STI is a strong independent predictor of CRT response.