在心室动期间经过心经冲击后的耐火间隔
R J Sweeney1, R M Gill, P R Reid
1Department of Electrophysiology Research, Eli Lilly and Co, Indianapolis, Ind, USA. sweeneyrj@sjm.com
Circulation
|December 1, 1996
概括
减振冲击会在心脏中产生短暂的耐火期,防止冲击后立即重新起动. 这种后冲击耐火间隔对于双相冲击比单相冲击要短.
科学领域:
- 心脏病学 心脏病学
- 电子生理学 电子生理学
- 医疗器械 医疗器械
背景情况:
- 快速的心室节奏表明除冲击后的耐火期.
- 需要对动期间的后冲击耐火间隔进行实验验证.
研究的目的:
- 为了确定在心室动期间除冲击后立即存在耐火间隔.
- 为了比较单相和双相冲击之间的后冲击耐火间隔持续时间.
主要方法:
- 被麻醉的狗接受了单相或双相冲击,随后进行了后冲击刺激 (PSS).
- 测量了50%除成功的冲击电流 (I50).
- 与冲击相比,PSS的时间是不同的.
主要成果:
- 1.0-A PSS在单相冲击后50-90毫秒时显著增加了I50.
- 1.0-A PSS在双相冲击后也增加了I50,但比单相冲击后的程度更大.
- 在任何测试时间,0.5-A PSS对I50没有影响.
结论:
- 在动期间单相和双相冲击后存在一个后冲击耐火间隔.
- 与单相冲击相比,这种耐火间隔在双相冲击中较短.
- 这些发现支持了对除的耐火期延长假设.
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