不同永久起搏电极植入右心室心尖部的损伤电流变化

目的 探讨不同永久起搏电极植入右心室心尖部后损伤电流（current of injury，COI）的变化特点。方法 入选144例右心室心尖部植入永久起搏电极患者，分为被动电极组及主动电极组。测定电极固定后0、5和10 min的COI及常规起搏参数，分析COI变化特点。结果 被动电极固定后0、5和10 min分别测定COI值均明显小于主动电极固定后测定的COI值（P<0.01）。两种电极固定后COI随时间均显著逐步下降（P<0.01），被动电极固定后COI值下降幅度明显大于主动电极（P<0.01）。被动电极固定后10 min内后5 min COI下降幅度大于前5 min下降幅度（P<0.01），主动电极固定10 min内COI值前后5 min下降幅度未见差异。术后3例患者电极脱位，其COI均<5.0 mV。结论 右心室心尖部植入被动电极产生的COI明显小于主动电极，两种电极产生的COI均随时间逐步减小，被动电极产生的COI下降速度较快。

Current injury of different permanent leads in right ventricular apical pacing

AIM To investigate characteristics of current injury (COI) of different permanent leads in right ventricular apical pacing. METHODSOne hundred and forty-four patients were divided into passive fixed lead group and active fixed lead group. Subjects were implanted with permanent pacing lead in right ventricular apical. We determined COI and conventional pacing parameters at 0, 5 and 10 min after lead fixed and the characteristics of COI were analyzed. RESULTSIn the 146 patients, COI could not be measured accurately in two cases due to the large amplitude of intracardiac electrogram (ICEG). COI gradually reduced after lead fixed in the remaining 144 cases. COI at 0, 5 and 10 min after passive fixed lead was significantly lower than after active fixed lead (P<0.01). The decline of COI of passive fixed lead was significantly greater than active fixed lead (P<0.01) and COI of three cases with postoperative dislocated lead was <5.0 mV. CONCLUSIONCOI of passive fixed lead is significantly smaller and decreases faster than active fixed lead in right ventricular apical pacing. COI produced by both passive fixed lead and active fixed lead will decrease gradually after lead fixed.