组织速度显像对急性心肌缺血下左室压力变化与左房功能影响的相关性研究

目的：应用超声组织速度显像（TVI）技术研究左室局部心肌缺血时左室压力变化对左房功能的影响。方法：11只犬行左冠状动脉前降支结扎，制作左室前壁心肌缺血模型。应用TVI技术测量缺血前后心房各壁的收缩期峰值速度（Vs）、舒张早期峰值速度（Ve）及二尖瓣口血流频谱E／A、肺静脉血流频谱S峰和D峰值，同时导管记录缺血前后左室压力曲线。结果：心肌缺血后左房各壁Vs和Ve均增高（P〈0．001），左室舒张末期压力（LV—EDP）增高，且其缺血前后变化率（LVEDP％）分别与左房前壁、侧壁和下壁的Ve变化率（Ve％）呈正相关（r=0．72、0．73、0．83，P＝0．05、0．05、0．002）。结论；左房功能在局部心肌缺血时会受到增高的LVEDP的影响，表现为左房壁心肌纤维的运动能力随之增加。

The correlation study of left ventricular pressure changing on left atrium function studied with tissue Velocity imaging under acute left Ventricular ischemia

Objective: To evaluate whether left ventricular(LV) pressure changing will affect the left atrium(LA) function during the LV ischemia using tissue velocity imaging(TVI).Method: Eleven healthy dogs were occluded with left anterior descending coronary artery(LAD)for regional acute ischemia.Peak systolic velocity(Vs)and early diastolic velocity(Ve)of LA walls and catheter-measured pressure of LV were measured at pre and post ischemia respectively.Results: All Vs and Ve values increased after ischemia(P<0.001).Left ventricular end diastolic pressure (LVEDP) increased after ischemia(P<0.0001) and its changing rate LVEDP% positively correlated with Ve % of anterior,lateral and inferior wall respectively(r=0.72,0.73,0.83.P=0.05,0.05,0.002).Conclusion: LA function will be partially affected by the LVEDP changing raised by regional LV ischemia.Presented as the compensated increased wall deformation after regional acute LV ischemia.