实时三维超声心动图评价右室不同部位起搏对左室收缩同步性和心功能的影响

目的运用实时三维超声心动图及其定量技术分析右室不同部位起搏12月后左心室收缩同步性和功能的变化。方法25例安装永久起搏器的患者分成2组：右室流出道（RVOT）组12例，平均年龄（61．5±8．9）岁；右室心尖部（RVA）组13例，平均年龄（62．8±5．9）岁。分别于术后第1天和12个月使用二维M型超声心动图测左房内径（LAD），实时三维经胸超声心动图检查，应用Qlab定量分析软件得到左室整体容积曲线、17节段容积啦线、舒张末容积（EDV）、收缩末容积（ESV）和左室射血分数（LVEF），17节段的平均最大容积（Vmax）及其标准差（Vmax-sD）、平均最小容积（Vmin）及其标准差（Vmin-sD）、最小容积点距离心电图Q波起始点的平均时间（T）及其标准差（T—SD）、17个节段中的最小容积点距离心电图Q波起始点的最大时间差（Tmax），测得NT—proBNP和QRS。结果基线状态各指标差异均无统计学意义（均P〉0．05）。随访12个月，RVOT组与RVA组比较，LVEF明显增大，ESV明显缩小，Vmin-SD、Vmax-SD明显减小，T—SD、Tmax缩短（P〈0．05），NTproBNP明显升高（P〈0．05），QRS差异无统计学意义（P〉0．05），房颤发生率明显减少（P〈0．05）。RVA组起搏器置入12个月较第1天时Vmax-SD、T—Vmin-SD、T—SD、ESV、NTproBNP明显增大，LVEF明显降低（P〈0．05）；而RVOT组无明显变化。RVOT组较基础态QRS增宽，但与RVA组无明显区别（P〉0．05）。结论实时三维超声心动图能够评价左室心肌收缩同步性和左心收缩功能，右室流出道起搏较右室心尖部起搏左室收缩的同步性好，左室收缩功能的影响小，是-种较为理想的起搏部位。

Assessment of left ventricular systolic synchronicity and function with different right ventricular site pacing by real-time three-dimensional echocardiography

Objective To assess left ventricular systolic synchronicity and function with right ventricular out tract （RVOT）and right ventricular apex （RVA）by real-time three-dimensional echocardiography. Methods Twenty-five subjects who were implanted permanent pacemakers were divided into two groups：RVOT group （n= 12） and RVA group （n=13）.Philips IE33 with X3-1 probe was used to perform full volume real-time three-dimensional echocardiography （3DE）, 17-segmental volume curves were obtained by the on-line Qlab software.The end-systolic volume （ ESV ）, end-diastolic volume （ EDV ）,left ventricular ejection fraction （LVEF）, the mean minireal volume （Vmin.） and its standard deviation（Vmin-SD ）, the mean maximal volume （Vmax） and its standard deviation （Vmax-SD）, the mean time to the point of minimal systolic volume （T） and its standard deviation （T-SD）, and the maximal difference of T among all 17 segments （Tman） were derived. NTpro BNP,QRS were measured 1st day and 12th month after implantation. Results There were no difference in baseline characteristics between two group（all P〉0.05）. After 12-month follow up, ESV,Vmin-SD,Vax-SD,T-SD,Tmax and NTproBNP in group RVOT wer（ significantly smaller than those in group RVA （P〈0.05）, and LVEF of group RVOT was significantly higher than that of RVA group （P〈0.05）. While Vmax, Vmin, and T were not significantly different between the two groups （P〉0.05）. In Group RVA, Vmax-SD, Tmax, Vmin-SD,T-SD, ESV, NTproBNP on 12 month were significantly increased than on 1st day. Conclusion Real-time three-dimensional echocardiography is useful to evaluate left ventricular synchrony and function. RVOT pacing in patients is associated with more favorable myocardial contraction and mechanical synchrony compared with right apical pacing.