Safety evaluation and short-term efficacy in left bundle branch pacing patients with ventricular pacing dependence

Objective To compare the electrical parameters, lead parameters and position stability of left bundle branch pacing (LBBP) and right ventricular septal pacing (RVSP), and to evaluate its feasibility, safety and synchronization.

Methods A total of 37 patients with SSS or AVB diagnosed were analyzed retrospectively, including 20 patients with LBBP and 17 patients with RVSP.The clinical follow-up data and complications were recorded.

Results Eighteen cases (90%) of ventricular leads were successfully implanted in the LBBP group, and 19 cases (100%) in the RVSP group.The intraoperative pacing threshold and perception in the LBBP group were higher than those in the RVSP group (P < 0.05).The pacing thresholds of both groups decreased after surgery compared to those during surgery (P < 0.01).In the LBBP group, postoperative pacing perception increased and pacing impedance decreased (P < 0.05 to P < 0.01).The postoperative QRS duration in the LBBP group narrowed compared to before surgery (P < 0.05), while in the RVSP group it widened compared to before surgery (P < 0.05).Compared with the RVSP group, the postoperative QRS duration in the LBBP group narrowed (P < 0.05) and LVAT shortened (P < 0.05).There was no statistically significant difference in LVEF and LVEDD between the LBBP group and the preoperative group at 3 months after surgery (P>0.05).There was no statistically significant difference in LVEF between the RVSP group and preoperative group at 3 months after surgery (P>0.05), but LVEDD expanded compared to preoperative group (P < 0.05).Compared with the RVSP group, LVEF improved and LVEDD decreased in the LBBP group at 3 months after surgery (P < 0.05).One case in LBBP group was successfully implanted with RVSP due to high pacing threshold and another due to large right atrium; one case in RVSP group had bag hematoma on the second day after operation, which was completely absorbed after treatment.There were no bag infection, electrode falling off, acute cardiovascular and thrombotic events in both groups.

Conclusions In patients with ventricular pacing dependence, LBBP group has stable parameters, less complications, feasibility and safety.LBBP group has good synchronization at short-term follow-up.