【摘要】 目的:通过M型及组织多普勒超声心动图探讨心脏电生理中的机械电延迟现象,并阐明可能的发生机制。方法:通过组织多普勒超声心动图(TDI)获取26例Ⅰ度房室传导阻滞患者的TDI下的等容收缩波S1起始时间至QRS波群起始点时间(S1-Q间期)、二尖瓣关闭时间点(C’点)至QRS波群起始点时间(C’-Q间期),并获取这2段时间内心肌的位移及应变;通过M型超声心动图获取M型超声下二尖瓣关闭时间点(C点)至QRS波群起始点时间(C-Q间期)。结果:26例患者S1起始均位于QRS波群起始之前,S1-Q间期为负值;23例患者C及C’点亦位于QRS波群起始之前。心肌在S1-Q间期及C或C’-Q间期内有明显的位移及应变。结论:在心脏的电生理中应当存在一种机械电延迟现象,这种现象的存在是由于心肌的收缩形式中还存在一种不由电信号掌控的收缩,即被动收缩。更多还原

【Abstract】 Objective To study the mechano-electric delay phenomenon,an unrecognized phenomenon and its mechanism in cardic cycle with M-mode echocardiography and tissue Doppler imaging(TDI).Methods The mitral valve closure point to the onset of QRS complex by M-mode and TDI(C-Q interval,C’-Q interval)and the onset of isovolumic contraction wave S1 to the onset of QRS complex(S1-Q interval)by TDI of 26 patients with first-degree AV block were obtained,as well as the displacements and strains of myocardium in C’-Q interval and S1-Q interval.Results The onset of S1 of 26 patients were ahead of the onset of QRS complex,furthermore,the mitral valve closure point of 23 patients were ahead of QRS complex too.The obvious displacements and strains of myocardium in C’-Q interval and S1-Q interval could be seen.Conclusion Because of passive contraction not controlled by electrical signals,another contraction fashion except active contraction,there should be exist a mechano-electric delay phenomenon in cardic cycle.更多还原