相关实验视频
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Programmed Electrical Stimulation in Mice
Published on: May 26, 2010
在人类心室中,超快速列车步伐的总和和抑制
C D Swerdlow1, L B Liem, M R Franz
1Cardiac Arrhythmia Unit, Stanford University Medical Center 94305.
Circulation
|November 1, 1987
概括
超快速刺激的列车可以捕捉心脏或抑制反应,这取决于刺激特征. 这项研究发现,火车在低电流下延长了有效的耐火期,但在高电流下缩短了它,阻碍随频率和持续时间的增加而增加.
科学领域:
- 电子生理学 电子生理学
- 心脏病学 心脏病学
- 医疗器械 医疗器械
背景情况:
- 动脉律障碍可以通过使用超快速刺激的早期单次捕获来终止.
- 刺激列车也可以抑制对后续刺激的反应.
- 了解列车特征对于优化抗失律策略至关重要.
研究的目的:
- 确定影响超快速刺激列车捕获与抑制的因素.
- 为了比较单个外刺激 (S2) 与100 Hz列车的强度-间隔关系.
- 为了研究脉冲频率的影响,火车的持续时间,和procainamide.
主要方法:
- 在29名患者中比较了S2和100 Hz,100 msec列车的右心室强度-间隔关系.
- 12名患者的脉冲频率 (50-200赫兹) 和11名患者的训练时间 (50-150毫秒) 变化.
- 在10名患者中评估了普罗卡因胺 (10.1 +/- 2.3微克/毫升) 的作用.
主要成果:
- 100赫兹列车在低电流强度 (抑制) 中延长了有效耐火期 (ERP),在高电流强度 (总和) 中缩短了它.
- 在0.5mA时,火车ERP比S2ERP长47毫秒;在16mA时,它比S2ERP短12毫秒 (p < .001).
- 抑制与脉冲频率,火车持续时间和普罗卡因胺一起增加;总和仅与脉冲频率一起增加.
结论:
- 刺激列车特征对有效耐火期 (ERP) 和功能耐火期 (FRP) 有不同的影响.
- 抑制和总和似乎是由不同的电生理学机制介导的.
- 优化刺激参数是有效的动脉节律失常管理的关键.
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