起搏器自动夺获功能中备用脉冲发放情况的临床观察

Observation of Backup Safe Pulses Releasing in AFFINITY Series Pacemakers

目的研究患者日常活动时,植入的起搏器自动夺获功能工作中备用脉冲的发放。方法对15例植入Affinity系列起搏器的患者进行24小时动态心电图记录,采取人工逐跳分析的人机对话方法对发放的备用起搏脉冲进行计数及分类。结果本组患者随访前一个月的起搏阈值0.62±0.26V～1.17±0.55V,随访当日的自动起搏电压1.06±0.29V。15例患者(100%)在真性或假性心室融合波后有备用脉冲的发放,1例(6.7%)因未检测到ER波(EvokedResponse)而发放,2例(13.3%)因自动输出的起搏电压不能夺获心室而发放,1例(6.7%)因感知不良,起搏脉冲落在自身心室除极后未夺获心室发放。没有发现自动输出电压起搏心室失败又无备用脉冲发放的情况。结论自动阈值检测及备用脉冲的发放受真性或假性心室融合波,以及快速心律失常的影响,高于起搏阈值0.25V的实际起搏电压能够有效起搏心室。

Objective To study the backup safe pulses releasing in AFFINITY Series Pacemakers during daily-life. Methods We studied 24-hour Holter recorded in 15 patients who had been implanted the Affinity SR series pacemakers(St. Jude Medical), and classified different kinds of the backup safe pulses manually by analyzing beat-by-beat. Results Backup safe pulses released after fusion/pseudo-fusion of ventricular complexes were in all 15 patients. Backup safe pulses were released because E/R was not detected in 1 patient(6.7%), and auto putout couldn't capture the ventricular muscles in 2 patients(13.3%).In 1 case(6.7%)because ventricular sensitivity was not sufficient, some pulses were released after self repolariztion and could not capture the heart, which contributed to the backup safe pulse release. We hadn't found that no backup safe pulses released when the auto putout pace pulses lost capture. Their chronic pacing threshold in the latest month was between0.62±0.26V and 1.17±0.55V,and the auto output on the testing day was 1.06±0.29V. Conclusion Auto threshold examining and backup safe pulses releasing can influenced by fusion/pseudo-fusion and tachyarrhythmia. Pacing by 0.25V higher than the threshold can capture the cardiac muscles effectively.