组织多普勒显像评价右心室不同部位起搏对左心室收缩同步性的影响

Evaluating left ventricular systolic synchrony of different right ventricular pacing sites by tissue Doppler imaging

目的运用组织多普勒显像技术测量右室不同部位起搏的心脏超声参数，以评价右室不同部位起搏对左室收缩同步性的影响。方法连续人组69例拟行起搏器植入术的患者，术前随机分为A组[36例，右室流出道起搏（right ventricular outflow tract pacing，RVOT）]及B组[33例，右室心尖起搏（right ventricular apex pacing，RVA）]，分别于术前及术后3个月进行超声心动图检查，测量左室12节段收缩达峰时间（Ts）及收缩峰速度（Vs），计算12节段Ts标准差（Ts-SD）及Vs平均值（Vs-M）。结果A组和B组各有1例患者随访时因非起搏心律而剔除，共获得67例患者的组织多普勒图像进行脱机分析。术前两组左室收缩同步性差异无统计学意义，术后RVOT起搏组（A组）左室收缩同步性优于RVA起搏组（B组），差异有统计学意义[Ts—SD（23．63±2．32）ms对（31．54±2．93）ms，P=0．03873，对基础状态下Ts—SD≥32．6ms者进行亚组分析（A2组和B2组）RVOT起搏后Ts-SD显著小于术前[（28．55±16．93）ms对（48．19±9．26）ms，P=0．0045]，而RVA起搏前后Ts-SD差异则无统计学意义，两亚组术后比较RVOT起搏亚组（A2组）Ts-SD显著小于RVA起搏亚组（B2组）[（28．55±16．93）ms对（38．19±18．34）ms，P=0．0290]。结论RVOT起搏对于左室收缩同步性影响小于RVA起搏，术前同步性较差者选择RVOT起搏能显著改善左室收缩同步性。

Objective To evaluate the effects of different right ventricular pacing sites on left ventricular systolic synchrony using tissue Doppler imaging（TDI）. Methods A total of sixty-nine patients with indications for permanent pacemaker implantation were enrolled sequentially by Pace-ROAD study（Pacemaker-right ventricular outflow tract and apex study,a randomized control study）. They were randomized to RVOT pacing group（group A） or RVA pacing group（group B）. Echocardiographic study with TDI was performed before and after 3 month follow up, and the data were analysed off-line. The peak velocity（Vs）, the time to the peak of S wave（Ts） of all 12 basal and middle segments of left ventricle were measured, and then the standard deviation of Ts （Ts-SD）, the average of Vs （Vs-M） were calculated. Results Thirty-six patients were randomized to group A,while the other 33 patients to group B. In each group,one patient was rejected due to non-pacing rhythm during follow-up. After 3 month pacing,the Ts-SD of group A was significantly shorter than that of group B[（23.63±2.32）ms vs （31.54 ± 2.93）ms, P = 0. 0387]. In the patients with the basal Ts-SD longer than 32.6 ms（group A2 and group B2） ,the Ts-SD was significantly shortened than the baseline in group A2 during follow-up,while no significant difference was found in group B2. And the follow-up Ts-SD of group 132 was significantly longer than that of group A2 [（38.19±18.34）ms vs （28.55± 16.93）ms, P = 0.0290]. Conclusions RVOT pacing is associated with favorable left ventricular systolic synchrony than RVA pacing, especially in patients with worsened baseline systolic synchrony.