右心室流出道间隔部起搏和心尖部起搏对双心室同步性的影响

Effects of the right ventricular outflow tract septal pacing on biventricular synchronization in comparison with the right ventricular apical pacing

目的评价右心室间隔部起搏和右心室心尖部起搏对双心室同步性的影响。方法植入永久起搏器的患者20例,按照心室电极的位置,随机分为右心室流出道间隔部起搏组(RVOTS组)和右心室心尖部起搏组(RVA组)。对两组患者术前、术后QRS波形态和宽度以及术前、术后3个月随访时的左心室射血分数(LVEF)、室间隔-左心室后壁之间的运动延迟(SPWMD)和心室间机械运动延迟(IVMD)进行比较。结果两组患者均成功植入起搏电极导线和起搏器,随访期间无电极脱位和其他并发症发生。两组患者在年龄、性别以及术前所测定的LVEF、SPWMD及IVMD水平差异无统计学意义(P>0.05);与术前相比,RVS组起搏心电图Ⅱ导联QRS时限无明显变化,而RVA组较术前及RVOTS组显著延长;术后3个月随访,RVOTS组LVEF、SPWMD、IVMD较术前无明显变化,而RVA组LVEF较术前下降,SPWMD、IVMD较术前延长,RVA组和RVS组相比,LVEF显著下降,SPWMD、IVMD显著延长。结论RVA起搏使左、右心室不同步,RVOTS起搏和RVA起搏相比,使双心室开始除极时间差缩短,尽可能地维持了双心室激动顺序和双心室的同步性,对心脏功能的影响较小,RVOTS起搏比RVA起搏更接近生理性起搏。

Objective To investigate the different effects of the right ventricular outflow tract septal（RVOTS） pacing on biventricular synchronization in comparison with the right ventricular apical（RVA） pacing.Methods According to the location of ventricular lead,a total of 20 patients implanted with permanent pacemaker and ventricular lead were randomly divided into RVOTS group and RVA group.The morphology and duration of QRS complexes were compared before and after the implantation within and between the two groups,and in addition left ventricular ejection fraction（LVEF）,septal to posterior wall motion delay（SPWMD）and interventricular mechanical delay（IVMD） were compared before and three months after the implantation within and between the two groups.Results All patients were successfully implanted with permanent pacemaker and ventricular lead.During the follow-up,ventricular lead dislodgement and other complications did not take place.No major differences were identified in age,gender,LVEF,SPWMD,and/or IVMD determined before the implantation between the two groups（P 0.05）.Compared with spontaneous QRS duration of pre-implantation,paced QRS duration did not change significantly in the RVOTS group,but in the RVA group paced QRS duration increased significantly in comparison with spontaneous QRS duration of pre-implantation and paced QRS duration of the RVOTS group.In the RVOTS group there were no significant differences in LVEF,SPWMD,and IVMD three months following the implantation,however,compared with pre-implantation,LVEF decreased and SPWMD,IVMD increased after three months in the RVA group.LVEF was longer significantly and SPWMD,IVMD were lower significantly during RVA pacing than those during RVOTS pacing.Conclusion RVA pacing makes biventricular dissynchrony.Compared with RVA pacing,RVOTS pacing maintains biventricular activation sequence and biventricular synchronization as much as possible,it has smaller effects on cardiac function.So RVOTS pacing is closer to physiological pacing,by comparison with RVA pacing.