定量组织速度成像对等容收缩波的再认识

Re-recognization of isovolumic contraction wave with quantitative tissue velocity imaging

目的通过定量组织速度成像研究组织多普勒(TDI)等容收缩波S1时间段内心动周期时相的变化。方法通过超声心动图TDI法及脉冲多普勒(PWD)法比较电-机械延迟时间(EMD)、等容收缩时间(IVCT)和射血前期时间(PEP),观察TDI法QRS波群起始至二尖瓣关闭时间(MCT)、等容收缩波起始至二尖瓣关闭时间(ICMC)。结果TDI所测IVCT较PWD法时间长,TDI法所测EMD较PWD法时间短,TDI法MCT即为PWD法EMD时间,ICMC为等容收缩前期时间。结论TDI的等容收缩波S1内包含着两个时相,等容收缩前期和等容收缩期。

Objective To explore the phase change of cardiac cycle in isovolumic contraction wave S1 period of tissue velocity imaging（TDI）with quantitative tissue velocity imaging（QTVI）.Methods Electric mechanical delay time（EMD）,isovolumic contraction time（IVCT）and pre-ejection time（PEP）were detected with TDI and pulsed-wave Doppler（PWD）.The beginning of QRS wave and the isovolumic contraction wave S1 to the point of mitral valve closing time with TDI（MCT,ICMC）were observed.Results IVCT measured with TDI was longer than that with PWD.EMD measured with TDI was shorter than that with PWD.MCT measured with TDI was equal to EMD measured with PWD.ICMC was the time of pre-isovolumetric contraction.Conclusion Isovolumic contraction wave of TDI contains two phases,i.e.pre-isovolumetric contraction and isovolumic contraction.Despite the traditional isovolumic contraction period and ejection period,there is pre-isovolumetric contraction phase in the systolic period of heart.