右心室不同部位起搏对心脏收缩同步性及心功能的影响

目的比较右心室流出道（right ventricular outflow tract，RVOT）起搏与右心窀心尖部（riht ventficular apex，RVA）起搏对心脏收缩同步性指标及收缩功能的影响。方法2004年1月至2005年1月在我院植入VVL／VVIR，DDD／DDDR起搏器的患者，随机接受RVA起搏和RVOT起搏。植入前检查12导联体表心电罔及超声心动图，记录QRS时限、左心室舒张末内径（LVEDD）、左心房内径（LAD）、左心事射血分数（LVEF）。植入后记录心室起搏状态下的QRS时限。随访时间为2年，随访内容包括LVEDD、LAD、LVEF，同时应用脉冲组织多普勒技术测定心室问激动延迟（IVMD）以及左心室内收缩同步性指标（Ts-SD）。结果共随访30例患者，其中RVA起搏17例，RVOT起搏13例，两组患者间年龄、性别及心血管疾病等基本情况筹异无统计学意义。植入前两组患者问QRS时限、LVEDD、LAD及LVEF差异无统计学意义，植入后RVOT起搏状态下QRS时限较RVA起搏明显缩短（140．15±11．36）ms对（160．76±23．68）ms，P=0．033]，植入后两组间IVMD（25．7±9．1）mS对（36．7±10．0）ms，P=0．076]比较差异无统计学意义，两组问Ts—SD（13．34ms对42．96ms，P=0．001）比较差异有统计学意义；植入后随访两年，两组患者间LAD差异无统计学意义（43±6）ms对（42±9）ms，P=0．759]，同RVA组相比，RVOT组LVEDD缩小（5．10±0．76）mm对（5．28±0．40）mm，P=0．048]，LVEF明显增加（0．56±0．04对0．52±0．02，P=0．001）。结论同右心窄流出道起搏相比，右心室心尖部起搏对患者心功能呈负性影响，且加重左心室内不同步收缩。

Long-term effects of different pacing sites of right ventricle on left ventricular mechanical synchrony and systolic function

Objective To compare long-term effects of right vcntricular apex(RVA) and right ventricular outflow tract(RVOT) pacing on synchronization and left ventriculac(LV) fuction.Methods Patients with indications for permanent pacing,admitted to hospital from January 2004 to January 2005,were randomized to receive RVA or RVOT pacing.QRS duration and echocardiographic parameters were measured before implanting and 2 years after implanting,respectively.In addition,intervcntricular dyssynchrony and intraventricular dyssynchrony were assessed by PW-TDL Results Out of 30 patients 17 were randomized to the RVA group and 13 to the RVOT.There is no difference between groups in basic characteristic ,QRS duration ,LVEDD ,LAD and LVEF before operation.Compared with RVA pacing,RVOT pacing shortened QRS duration (140.15±11.36 )ms vs (160.76±23.68 ) ms,P=0.033 ).There is no difference in IVMD (25.7 ±9.1 ) ms vs ( 36.7 ± 10.0 ) ms,P = 0.076 ,hut the difference in Ts-SD was significant (13.34 ms vs 42.96 ms,P =0.001 ).Compared with the RVA group,RVOT pacing decrease LVEDD (5.10 ± 0.76 ) mm vs ( 5.28 ± 0.40 ) mm,P=0.048 ),and increase LVEF(0.56 ±0.04 vs 0.52 ±0.02,P=0.001 ).Conclusion RVOT pacing is associated with more favorable long-term effect in LV function and mechanical synchrony compared with RVA pacing.