心脏起搏器更换时单极心室电极参数的变化及其意义

Changes and clinical significance of parameters of implanted ventricular unipolar leads in patients with cardiac pacemakers replacement

目的:探讨更换起搏器时单极心室电极直接参数的变化及其临床意义。方法:对82例II^III度房室传导阻滞或病窦综合征患者,在起搏电能耗竭更换起搏器安置术中,应用起搏分析仪直接测量原心室起搏电极参数,并随访观察更换后起搏器功能变化情况。结果:至测量时原心室起搏电极在体内埋置时间为64~172,平均(109.2±26.4)个月,首次埋置时的起搏阈值为(0.64±0.32)V,更换脉冲发生器时为(1.55±0.62)V(P<0.05),更换脉冲发生器时,起搏电极阻抗(756.5±156.8)Ω,更换起搏脉冲发生器后,继续使用原心室起搏电极79例,术后随访1~151,平均(68.3±30.6)个月,3例于更换术后17~46个月,出现起搏器感知功能不良,重新手术时发现为导管不全断裂、绝缘层包鞘破损,其余病人起搏与感知功能均良好。结论:心室单极起搏电极使用约9年以后,大多电极的直接测量参数仍在良好范围,可以考虑继续使用,但必须注意随访,定期复查。

Objective： To investigate the changes and clinical significance of the parameters of implanted ventricular unipolar leads in the patients with cardiac＇ pacemakers replacement. Methods： A total of 82 patients with cardiac pacemakers were replaced because of battery exhaust. The direct lead parameters of implanted ventricular leads were measured in replacement using a pacing system analyzer. The functions of the new pacemakers were observed. Results： The implanted ventricular unipolar leads had been implanted for 64-172 （109. 2±26.4） months. The chronic pacing threshold of leads during pulse generator replacemem were higher than the initial pacing threshold [ （0. 64±0.32V ） vs. （1.55±0.62V）, P〈0. 05]. The old lead impedances were （756.5±156.8） Ω during pulse generator replacement. Postoperatively, 79 old leads were continued to perform the pacing function and were followed up for 1 -151 （68. 3±30. 6） months. Leads malfunction occurred in 3 patients in 17-46 months after replacement operation, including lead fracture and insulation defect. Conclusion： Most direct parameters of implanted ventricular unipo- lar leads are in normal ranges after 9 years, and can be considered to continue performing pacing function. Follow up should be taken regularly for those patients.