右室流出道与右室心尖部起搏对心脏收缩功能和左室重构的影响

目的评价右室流出道(RVOT)和右室心尖部(RVA)起搏对心脏收缩同步性、收缩功能和左室重构的影响。方法82例高度或III度房室传导阻滞患者随机分为RVOT起搏组(A组,n=43)和RVA起搏组(B组,n=39),以术前左室12节段达峰时间标准差(Ts-SD)是否>32.6ms对两组患者进行亚组分组,Ts-SD>32.6ms者为A1亚组与B1亚组,Ts-SD≤32.6ms为A2亚组与B2亚组。于术前及术后6个月分别进行超声心动图检查,测量舒张末左室容积(LVEDV)、收缩末左室容积(LVESV)、左室射血分数(LVEF),并采集组织多普勒图像(TDI)进行脱机分析,测量主动脉瓣射血前时间(APET)、肺动脉瓣射血前时间(PPET)、左室12节段收缩达峰时间(Ts),计算室间电机械延迟(IVMD)和Ts-SD。结果术后6个月,两组的IVMD均较术前增加;两组Ts-SD与术前比无差异。亚组分析表明术前同步性好的A2、B2亚组术后Ts-SD升高;术前同步性差的A1亚组术后Ts-SD降低。术后6个月两组LVEDV、LVESV及LVEF与术前比较均无差异,组间比较亦无差异。结论RVOT和RVA起搏短期内对左室收缩功能及左室重构均无影响,术前收缩不同步者可从RVOT起搏中获益。

The effects of right ventricular outflow tract and right ventricular apex pacing on left ventricular systolic function and cardiac remodeling

Objective To evaluate the effects of right ventricular outflow tract （RVOT）and right ventricular apex （RVA） pacing on left ventricular systolic synchrony and cardiac remodeling. Methods A total of 82 patients with high degree or complete atrioventIicular block were enrolled and were randomized into two different cardiac pacing sites of RVOT （Group A, n =43 ）and RVA（ Group B, n = 39）, We diveded the two groups into four sub-groups according to whether or not Ts-SD 〉 32.6 ms, Ts-SD 〉 32.6 ms were A1 and B1 subgroup, Ts-SD ≤〈32.6 ms were A2 and B2 subgroup. 2D echocardiography was used to measure the left ventricular end diastolic volume （LVEDV） , left ventricular end systolic volume （LVESV） and left ventricular ejection fraction （LVEF） at pre-operation and after six months pacing. Meanwhile, standard deviation of the time to peak of S wave of left ventricle 12 basal and middle segments （Ts-SD） and inter ventricular mechanical delay （IVMD） were measured by tissue Doppler imaging （TDI）. Results There were no significant difference about Ts-SD between at 6 months and pre-operation. In sub-group analysis, the Ts-SD of A2, B2 subgroup in 6 months were higher than before, while the Ts-SD of A1 subgroup in 6 months were lower than before. There were no significant difference about LVEDV, LVESV and LVEF between at 6 months and pre-operation. Conclusions Patients who are asynchronized at pre-operation can benefit from RVOT pacing. But its advantage still need long time to follow - up.