不同起搏百分比对患者心功能的影响

目的比较在不同的心室起搏百分比下右室心尖部起搏的患者对心室同步性及心功能的影响。方法入选因房室传导阻滞(AVB)或病态窦房结综合征(SSS)而接受DDD或VVI起搏治疗的患者60例,其中植入DDD型起搏器44例,植入VVI型起搏器16例。根据最终心室起搏百分比(Cum%VP)将其分为三组:A组Cum%VP60%(20例),B组Cum%VP≥60%～100%(20例),C组Cum%VP=100%(20例)。通过观察患者的6 min步行试验(6MWT)、监测血浆BNP的变化、QRS时限的变化及常规二维超声,评价不同起搏百分比对心功能影响。采用组织多普勒测量室间隔及左室各壁基底段、中间段的收缩达峰时间(Ts)并计算其标准差(Ts-SD)及脉冲多普勒采集主动脉瓣血流频谱,计算从QRS起始到主动脉及肺动脉血流出现时间,评价心室同步性。结果三组患者阈值变化及手术并发症的发生率均无统计学差异;12月后三组QRS时限及BNP均较术前增加,而活动耐量均较术前下降,其中A组QRS波时限增量及BNP增量均小于B、C组,C组活动耐量下降程度大于A、B组,12个月后三组患者左房内径、左室收缩末期内径扩大(P0.05),E/Ea较术前增加,射血分数减少(P0.01),其中C组射血分数下降程度大于A、B组(P0.01);与B、C组相比,A组患者Ts与PPEI-APEI较小(P0.05)。结论右室心尖都起搏时,随着Cum%VP的增加,心功能恶化程度及心室的失同步化越明显。

Impacts of different cumulative percentage of ventricular pacing on heart function

Objective To evaluate ventricular synchrony and cardiac function changes under the different cumulative percentage of ventricular pacing.Methods A total of 60 patients received permanent cardiac pacemaker for atriventricular block（AV block） or sick sinus syndrome（SSS）.Two different cardiac pacing modes of VVI（n=16）and DDD（n=44）were performed.According to the final cumulative percentage of ventricular pacing（Cum%VP）,the subject were divided into three groups：group A：Cum%VP60%（n=20）;group B：Cum%VP≥60%~100%（n=20）;group C：Cum%VP=100%（n=20）.After 12-month installment of the pacemakers,we investigated patients by 6 min walk,BNP,the change of QRS duration.Tissue Doppler imaging was used to evaluate the time to peak in systolic phase of interventricular septum.The ventricular synchrony was evaluated by QRS duration,PPEI-APEI and Ts.Results There were no differences in threshold parameters and incidence of complications between three groups.The QRS duration and the increment in BNP decreased compared,with preoperative which were all significantly changed after ventricular pacing.The increment in group A is less than that in group B and C.LAD、LVIDs and E/Ea（P0.05）were larger and LVEF（P0.01） was less in group C than in group A and B,LVEF（P0.01） was also less in group A.Compared with group B and C Ts and PPEI-APEI（P0.05） is less in group A.Conclusion At the point of the right ventricular apex pacing,with the increasing in Cum% VP,the increasing deterioration of cardiac function and ventricular desynchronicity are more obvious.