VVI型起搏器更换时心室电极直接参数的变化及临床意义

研究长期起搏器治疗后起搏阈值、电极阻抗的变化及电极使用的寿命。 32例病人 ,在起搏器置入术及更换术时 ,用起搏器分析仪直接测量心室电极参数。心室电极在体内埋置时间为 10 4 .2 2± 30 .10 (49～ 16 8)个月。置入时起搏阈值为 0 .72± 0 .33(0 .2～ 1.5 )V ,更换脉冲发生器时为 1.85± 0 .75 (1.0～ 3.5 )V ,P <0 .0 0 0 1。更换脉冲发生器时起搏阈值是置入时的 2 .5 7倍 ,增加幅度为 2 0 1.2 %± 16 2 .9% (10 %～ 70 0 % ) ,增加绝对值为 1.13± 0 .71(0 .1～2 .5 )V。置入时电极阻抗为 6 4 2 .83± 185 .39(333～ 980 )Ω ,更换脉冲发生器时为 70 2 .79± 73.0 0 (40 2～ 12 4 0 )Ω ,P >0 .0 5。更换起搏器后 ,对继续使用原心室电极的 2 8例随访 5 4 .91± 5 1.2 1(1～ 16 8)个月。 3例在更换术后 1～ 2 4个月分别出现起搏及感知障碍 ,再次手术时发现导管不全断裂、绝缘包鞘破损及微脱位。结论 :置入性右心室心内膜电极在使用 8年以上 ,大部分的直接参数在正常范围 ,可考虑继续使用 ,但早年生产的电极 ,更换术时参数即使正常 ,亦不排除电极可能短期内发生故障 ,须随访及定期复查。

Clinical Significance of the Direct Lead Parameters Measurements on Implanted Ventricular Leads in the Patients With Pulse Generator Replacement.

To investigate the change of pacing threshold and lead impedance and the service life of lead after long pacing treatment,32 patients were involved.Direct lead parameters of implanted ventricular leads that had been implanted for 104.22±30.10(49～168) months were detected using a pacing system analyzer during pulse generator replacement.Results:The chronic pacing thresholds of lead during pulse generator replacement were higher than initial pacing threshold (0.72±0.33 V vs 1.85±0.75 V, P <0.0001).The chronic pacing threshold was 2.57 times higher than that during initial implantation (with mean increased value of 1.13 ± 0.71 V).There were no significant changes in lead impedance (642.83±185.39 Ω vs 702.79±73.00 Ω, P >0.05) during pulse generator replacement.Follow up was taken for the 28 patients who continued to use the original ventricular leads after replacement of the pacemaker,with mean follow up for 54.91±51.21(1～168) months.Lead malfunction occurred in 3 patients in 1～24 months after replacement operation,including lead fracture and insulation defect,etc.Conclusion:Most direct parameters of implanted ventricular leads are in normal rangers after 8.6 years,and can be considered to continue performing pacing function.The problems of the lead occurred within short time is not likely to be avoided.Follow up and examination in certain period is need.For ceads made in early years their parameters may be normal during replacement.