右心室心尖部起搏与右心室流出道起搏的临床研究

目的利用超声多普勒优化房室间期后，比较右心室心尖部（RVA）起搏与右心室流出道（RVOT）起搏对左、右心室间收缩同步性的差别。方法（1）共入选45例三度房室阻滞患者，其中男16例，女29例。RVA组31例，RVOT组14例，出院前进行程控。（2）将感知的房室间期（SAV）由70～170ms递增，每次递增20ms，分别行超声心动图检查，测定心肌做功指数（MPI），将MPI最小时的SAV确定为最适SAV。比较不同起搏部位所测最适SAV的差异。（3）应用组织多普勒同步图（TSI）技术分别测量左、右心室侧壁基底部心肌收缩达峰时问，二者之差用ATs表示，代表室间不同步程度。比较不同起搏部位ATs的差异。结果（1）RVA与RVOT起搏的最适SAV分别为（80．0±9．8）ms对（92±18）ms，差异有统计学意义（P〈0．01）。（2）RVA与RVOT组室间隔与左心室侧壁收缩达峰时间差分别为（89．5±25．7）ms对（27．94-10．5）ms（P〈0．001），左、右心室侧壁基底部收缩达峰时间之差分别为（88．3±23．4）ms对（29．54-16．7）ms，差异有统计学意义（P〈0．001）。结论与RVA起搏比较，RVOT起搏对心室收缩同步性影响较小，分析其效果与RVOT起搏部位有关。

Comparison of synchronization of right ventricular apex pacing and right ventricular septum pacing

Objective To compare the contraction synchrony between different pacing site: right ventricular apex(RVA) and right ventricular outflow tract(RVOT). Methods Forty-five patients (16 men,29 women,(58±15)years)were studied.The patients were randomized into RVA group(n=31) and RVOT group (n= 14). Optimal sensed atrioventriculardelay( SAV) was achieved by providing the minimum myocardial performance index(MPI). After optimized, ventricular synchrony and cardiac performance were further evaluated by comparing the different pacing sites. Results Optimal SAV was(80.0±9. 8) ms for RVA pacing and(92± 18)ms for RVOT pacing(P<0.01). Lateral-to-Sepal wall delay in Ts( time to peak systolic velocity) was(89. 5 ±25. 7 ) ms for RVA pacing vs. ( 27.9± 10. 5) ms for RVOT pacing( P<0. 001) and Ts of left lateral wall to right wall was(88. 3±23.4)ms for RVA pacing vs. (29. 5±16.7)ms for RVOT pacing(P<0.001). The contraction synchrony of RVOT pacing improved significantly versus RVA pacing. Conclusion RVOT pacing can improve left ventricular contraction synchrony and cardiac performance compared to RVA pacing. The advantage of RVOT pacing was correlated with the pacing site.