Objectives: To compare the left ventricular systolic function between the 1eft bundle branch pacing (LBBP) and right ventricular septum pacing (RVSP) in patients with pacemaker dependence by three-dimensional speckle tracking imaging (3D-STI).
Methods: A total of 65 patients with atrioventricular block (AVB) (Mobitz type II second-degree AVB, high-degree AVB, or third-degree AVB), who underwent permanent cardiac pacing implantation including 32 patients receiving LBBP (LBBP group) and 33 patients receiving RVSP (RVSP group) from June 2018 to June 2019,were enrolled in this study. These patients met the following inclusion criterion: pre-operative left ventricular ejection fraction (LVEF)>50% and ventricular pacing rate>40% at 6-month programming follow-up; and the patients underwent echocardiography at pre-operation and 6 months after operation. The 3D-STI was used to obtain global longitudinal strain (GLS), global circumferential strain (GCS), global radial strain (GRS), and global area strain (GAS).
Results: All the patients in the LBBP group and the RVSP group had normal LVEF, there was no significant difference between the 2 group (P>0.05). The LVEF was slightly decreased at 6-month follow-up in the RVSP group, but there was no significant change compared with pre-operation (P>0.05). There were no significant difference in LVEF, GLS, GCS, GRS and GAS at pre-operation and 6-month after operation between the LBBP group and the RVSP group (all P>0.05). Compared with pre-operation, the GLS and GCS were significantly decreased in the LBBP group; while the GLS, GCS, GRS and GAS in the RVSP group were also significantly decreased at 6-month follow-up (all P<0.05).
Conclusions: For patients with pacemaker dependence and normal LVEF at pre-operation, the cardiac function in the LBBP group is not significantly better than that in the RVSP group in short term follow-up. But in terms of physiologic pacing and long-term cardiac function protection, the 1eft bundle branch pacing is an optimal pacing mode.
目的: 采用三维斑点追踪成像(three-dimensional speckle tracking imaging，3D-STI)技术对左束支起搏、右室间隔部起搏的心室起搏依赖患者左心室收缩功能进行对比研究。方法: 将2018年6月至2019年6月因Ⅱ度Ⅱ型、高度、Ⅲ度房室传导阻滞接受心脏永久起搏器植入术[要求术前左心室射血分数(left ventricular ejection fraction，LVEF)大于50%，在术后6个月完成了超声心动图随访且程控心室起搏比例大于40%]的65例患者纳入本研究，按起搏部位分为左束支起搏(1eft bundle branch pacing，LBBP)组(n=32)和右室间隔部起搏(right ventricular septum pacing，RVSP)组(n=33)，采用3D-STI技术获取左心室整体纵向应变(global longitudinal strain，GLS)、整体环向应变(global circumferential strain，GCS)、整体径向应变(global radial strain，GRS)、整体面积应变(global area strain，GAS)。结果: LBBP组和RVSP组的LVEF均正常，两组间差异无统计学意义(P>0.05)；RVSP组术后6个月随访时较术前有轻微的下降趋势，但差异无统计学意义(P>0.05)。两组间GLS、GCS、GRS、GAS于术前、术后6个月比较，差异均无统计学意义(均P>0.05)。与术前相比，LBBP组术后6个月随访时GLS和GCS明显降低；RVSP组术后GLS、GCS、GRS、GAS均明显降低，差异均有统计学意义(均P<0.05)。结论: 在术前心功能正常的心室起搏依赖患者中，LBBP对心功能的影响虽然在术后短期内并不明显优于右室间隔部起搏，但从生理性起搏、长远心功能保护的角度看，LBBP是值得优先选择的起搏方式。.
Keywords: left bundle branch pacing; left ventricular; systolic function; three-dimensional speckle tracking imaging; ventricular pacemaker dependence.