右室心尖部起搏对心脏功能正常患者左室收缩同步性及功能的影响

目的应用超声心动图组织多普勒技术评价右室心尖部起搏对左室收缩同步性及心脏功能的影响,探讨起搏诱发的心室不同步收缩对于心脏功能的影响机制。方法65例置入双腔起搏器的病窦综合征患者分别在心室节律全部为起搏节律或室上性节律状态下行常规及组织多普勒超声心动图检查,测量左室收缩功能及收缩同步性指标。结果右室完全起搏模式下左室收缩功能下降(射血分数:0.58±0.07 vs 0.61±0.01,P<0.001),左室6节段收缩期平均速度下降(4.0±1.5cm/s vs 4.7±1.6cm/s,P<0.001),心室收缩同步性下降(12节段达峰时间标准差:37.5±12.5ms vs 23.7±10.2ms,P<0.001),心室同步性恶化程度与收缩功能恶化中度相关(r=0.37,P<0.05)。结论右室心尖部起搏可致左室收缩不同步及左室功能降低。

The effect of right ventricle apical pacing on left ventricle systolic synchrony as well as function

Objective Right ventricle(RV) apical pacing might lead to left ventricle(LV) systolic function depression, the underlined mechanism is thought to be related to the systolic synchrony induced by RV pacing. The aim of this study is to explore the potential effect of systolic synchrony caused by RV pacing on LV function. Methods Sixty-five patients diagnosed as sick sinus syndrome and implanted with dual chamber pacemaker were assessed by conventional and color-tissue Doppler Imaging (TDI) both at the mode of ventricle sensing (Vs) and ventricle pacing (Vp) respectively. LV ejection fraction, LV asynchrony index (Ts-SD), LV outflow tract velocity time integral (LVOT-VTI), Tei Index and mean systolic velocity of the six basal segments (Mean Sm) were analyzed respectively. Patients were also divided into 2 groups according to the Ts-SD after RV pacing. Result During Vp mode, LVEF, LVOT-VTI, mean Sm and Tei index decreased together with increasing Ts-SD. LV systolic parameters decreased more in patients with higher Ts-SD during Vp. Furthermore, the changing of Ts-SD was moderately correlated to the mean Sm reduction. Conclusion LV systolic function is worsened by RV pacing, which is associated with systolic dyssynchrony.