实时三维经胸超声心动图评价右室不同部位起搏对左室收缩同步性和收缩功能的影响

目的 应用实时三维经胸超声心动图(RT-3D-TTE)评价右室流出道( RVOT)间隔部与右室心尖部(RVA)起搏对左室收缩同步性和收缩功能的影响.资料与方法 65例缓慢心律失常患者采用掷硬币随机法分为RVOT间隔起搏组35例,RVA起搏组30例.于起搏器植入术前当天、术后1个月、3个月、6个月及12个月分别行RT-3D-TTE检查并采集三维全容积图像,用Qlab软件测量左室16节段的最小容积点距离心电图QRS起始点平均时间的标准差(Tmsv 16-SD)和最大时间差(Tmsv 16-Dif).测量左室舒张末期内径( LVEDD)和左室射血分数(LVEF).结果 RVOT组和RVA组术前当天Tmsv 16-SD、Tmsv 16-Dif、LVEDD和LVEF差异无统计学意义(P＞0.05),但两组内术后1个月、3个月、6个月、12个月Tmsv16-SD、Tmsv 16-Dif均较术前增大(P＜ 0.05); RVOT组术后LVEDD和LVEF与术前比较差异无统计学意义(P＞0.05); RVA组术后6个月、12个月LVEDD较术前增大,LVEF减小(P＜0.05).两组间术后1个月、3个月Tmsv 16-SD、Tmsv 16-Dif、LVEDD和LVEF差异均无统计学意义(P＞0.05)；RVOT组术后6个月、12个月Tmsv 16-SD、Tmsv 16-Dif、LVEDD较RVA组小；LVEF较RVA组大,差异有统计学意义(P＜0.05).结论 RVOT和RVA起搏均可引起心脏收缩不同步,对左室整体收缩功能有一定影响.RVOT间隔部起搏较RVA起搏对左室同步性的影响小,是较好的右室起搏部位.

Assessment of Impact of the Right Ventricular Pacing on the Left Ventricular Systolic Synchrony and Function by Using Real Time Three Dimensional Transthoracic Echocardiography

Purpose To assess impact of the right ventricular out tract (RVOT) pacing and the right ventricular apex (RVA) pacing on the left ventricular systolic synchrony and function using real-time three-dimensional transthoracic echocardiography (RT-3D-TTE). Materials and Methods 65 patients with chronic cardiacarrhythmia were enrolled in the study and randomly divided into RVOT pacing group (n=35) and RVA pacing group (n=30). All the patients were examined by RT-3D-TTE on the day before implantation (baseline) and 1, 3, 6, 12 months later after implantation. The standard deviation (Tmsv 16-SD) and the maximum time difference (Tmsv 16-Dif ) of the mean time from the beginning of Q-wave of electrocardiography to the point at minimal systolic volume of all 16 segments were analyzed using Qlab software. left ventricular end systolic diameter (LVEDD) and left ventricular ejection fraction (LVEF) of left ventricle were measured. Results There was no significant difference of Tmsv 16-SD, Tmsv 16-Dif, LVEDD and LVEF at the baseline (P>0.05). Compared with the data at the baseline, Tmsv 16-SD and Tmsv 16-Dif significantly increased on the day of 1, 3, 6, and 12 months later after implantation in both groups (P<0.05). LVEDD increased and LVEF decreased on the day of 6 and 12 months later after implantation in RVA group. There was no significant difference in RVOT group. All the parameters at the baseline and the point of 1 and 3 months after implantation had no significant difference between RVOT and RVA groups; Tmsv 16-SD, Tmsv 16-Dif and LVEDD at the point of 6 and 12 months after implantation in RVOT group were smaller, LVEF were higher (P<0.05). Conclusion Both RVOT pacing and RVA pacing effect the systolic synchrony and function of left ventricle. But the effect caused by RVOT pacing is less than that caused by RVA pacing. RVOT is a better place to implant the pacemaker.