不同部位右室起搏对远期左心功能的影响评价

Effect of different right ventricular pacing sites on long-term cardiac function

目的探讨右室心尖部起搏及右室流出道起搏对远期左心功能的影响。方法将38例高度房室传导阻滞或病态窦房结综合征患者随机分为右室心尖部起搏组(20例)与右室流出道起搏组(18例),随访术后不同时期两组超声心动图所测左室内径、左室射血分数、左室E/Ea及左室Tei指数并进行比较;比较两组起搏的QRS时限,并与Tei指数进行相关分析。结果右室心尖部起搏的左室内径较术前增大,且随着植入时间的增加有增大趋势;左室射血分数则较术前下降;右室流出道起搏时左室内径及射血分数较术前无明显下降;右室心尖部起搏术后12个月、18个月二尖瓣E/Ea较右室流出道起搏同期增大、Tei指数亦增大。与术前相比,两组术后心电图QRS时限均有所增加,右室心尖部起搏组QRS时限为(92.48±16.55139.5±19.42,<0.01);右室流出道起搏组QRS时限为(98.29±16.76 128.94±21.36,<0.01),但前者QRS时限增宽幅度要大于后者(49.27±14.74 32.6±11.03,<0.01)。不同起搏时,QRS时限与Tei指数呈正相关(=0.584,<0.01)。结论与右室心尖部起搏相比,右室流出道起搏更有利于双心室电激动的同步性,且对心功能的不良影响小。超声心动图是评价不同起搏位置对心脏结构及功能影响的客观、有效的方法。

Objective To assess the effect of different fight ventricular pacing sites on cardiac function by echoc- ardiography. Methods Thirty-eight patients with sick sinus syndrome and high-degree atrioventricular block were randomized to right ventricular apex （RVA） pacing group and right ventricular outflow tract （RVOT） pacing group. The changes of left ventricular diameter （LVDd）, left ventricular ejection fraction （LVEF）, E/Ea, Tei index were col- lected to evaluate the feasibility of RVOT pacing; meanwhile the correlation between QRS duration and Tei index was also analysed. Results Compared with pre-implantation, LVDd increased and LVEF decreased in RVA pacing, but there were no significant changes in RVOT pacing. RVOT pacing were better in E/Ea 12 and 18 months after the operation （10.21-2.53 vs 8.4-2.24, 10.74--2.64 vs 8.61-2.16, P 〈 0.01）, and there were significant differences in Tei index （0.67-0.15 vs 0.56-0.14, 0.68-0.15 vs 0.57-0.13p 〈 0.01 ）. The QRS duration was significantly changed after ventricular pacing both in RVA pacing and RVOT pacing, but the increasment in RVA pacing was more than RVA pacing （49.27- 14.74 vs 32.6-11.03,P 〈 0.01 ）. The QRS duration had a positive relationship with Tei index （r=0.584, P 〈 0.01）. Conclusions Compared with RVA pacing, RVOT pacing can provide smaller variation in the duration of QRS complex, LVDd, LVEF, E/Ea and Tei index. RVOT pacing can also slow down the deterioration of cardiac fimction. Conventional echocardiography can provide a better option for pacing location on clinical pacing therapy.