素对人体内心动力潜力和QRS持续时间的频率依赖性影响
K Nademanee1, W G Stevenson, J N Weiss
1Department of Cardiology, West Los Angeles Veterans Administration Medical Center, CA 90073.
Circulation
|March 1, 1990
概括
尼丁在心率较慢时延长了作用潜力的持续时间,但在心率较快时的影响很小. 这种抗失常药物还以速度依赖的方式增加了QRS持续时间.
科学领域:
- 电子生理学 电子生理学
- 药理学 药理学 是一个学科.
背景情况:
- 奎尼丁是一种抗心律失常药物,已知对心脏电生理学有影响.
- 了解其依赖频率的作用对于临床应用至关重要.
研究的目的:
- 研究静脉注射胺对右心室动作潜力持续时间和QRS持续时间的速度依赖性影响.
- 评估素对心室耐火期的影响.
主要方法:
- 对10名患者进行了电子生理学研究,分别在输入金素之前和之后进行了该研究.
- 在各种节奏周期长度下记录了右心室单相动力潜和心电图信号.
- 超刺激技术被用来评估耐火期.
主要成果:
- 氨酸在较慢的节奏率 (600-400毫秒) 上显著增加了动作潜力的持续时间,但在较快的节奏率 (350-300毫秒) 上这种效果会减弱.
- 尼丁逐渐延长了QRS持续时间,以取决于速率的方式.
- 在对照期内没有观察到QRS持续时间的取决于速率的变化.
结论:
- 尼丁对心室动作潜力的持续时间表现出频率依赖的影响.
- 药物延长QRS持续时间也取决于速率.
- 这些发现凸显了素复杂的电生理学特征.
相关概念视频
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