Hurzeler P, De Caprio V, Furman S
Med Instrum. 1976 Jul-Aug;10(4):178-82.
Endocardial electrograms in 77 acute cases (at time of pacemaker implant) and 56 chronic cases (at time of pulse generator replacement, with electrodes in service for at least 6 months) were recorded. The peak-to-peak voltage and rate of rise, or slew rate, were compared acutely and chronically. Both parameters must simultaneously exceed given thresholds to trigger the sensing circuits of implantable pacemakers. The average chronic slew rate was half the average acute value. The maximum slew rate and voltage swing occur during the intrinsic deflection as a virtually straight line segment of the electrogram. The findings are consistent with the predictions of a mathematical model for genesis of the electrogram, and also with a model for explaining acute-to-chronic changes in stimulation current thresholds.
记录了77例急性病例（起搏器植入时）和56例慢性病例（脉冲发生器更换时，电极已使用至少6个月）的心内膜电图。对峰峰值电压和上升速率（即转换速率）进行了急性和慢性比较。两个参数必须同时超过给定阈值才能触发植入式起搏器的感知电路。慢性转换速率的平均值是急性值平均值的一半。最大转换速率和电压摆动出现在心内膜电图几乎呈直线段的固有偏转期间。这些发现与心内膜电图产生的数学模型的预测一致，也与解释刺激电流阈值急性到慢性变化的模型一致。
