电荷膨胀理论正确地预测了双相除波形的相位持续时间的最佳比率
C D Swerdlow1, W Fan, J E Brewer
1Division of Cardiology, Cedars-Sinai Medical Center, Los Angeles, Calif, USA. swerdlow@ucla.edu
Circulation
|November 1, 1996
概括
双相波形的最佳相位持续比取决于除器容量. 对于传统电容器来说,比率小于或等于1是最好的,而对于小型电容器来说,比率大于1是最优的,这支持了充电膨胀理论.
科学领域:
- 心血管科学 心血管科学
- 生物医学工程 生物医学工程
- 电子生理学 电子生理学
背景情况:
- 在除中,双相波形通常需要相位持续时间比率 (相位持续时间与相位持续时间) ≤1.1.
- 电荷膨胀理论表明,在第2阶段的最佳电荷去除取决于系统和细胞时间常数.
- 这项研究调查了除系统的时间常数是否影响最佳相位持续时间比.
研究的目的:
- 测试假设,双相除波形的最佳相位持续比取决于除系统的时间常数 (τs).
- 为了评估充电喷射理论关于相位持续时间比率和时间常数的预测.
主要方法:
- 通过静脉除的犬类模型 (n=8).
- 使用传统 (140 μF, τs ≈ 7.1 ms) 和小型 (40 μF, τs ≈ 2.0 ms) 电容器的两相波形来确定储能除门 (DFTs).
- 每个电容的测试相位持续时间比为0.5,1,2和3,相位持续时间为单相波形优化.
主要成果:
- 对于传统的140μF电容器,对于相位持续比率≤1的DFT显著较低,而相位持续比率>1 (P=.0003).
- 对于小型40μF电容器,对于相位持续比率>1的DFT显著较低,而相位持续比率≤1 (P=.0008).
- 对DFT (P=.0002) 的电容和相位持续比影响之间观察到显著的相互作用,小电容的DFT最小值较低.
结论:
- 对于常规除器电容器来说,最优的相位持续时间比为≤1,对于小电容器来说是>1.
- 这些发现支持了充电膨胀理论关于系统时间常数对最佳波形参数的影响的预测.
- 优化基于电容的相位持续比对于有效的除来说至关重要.
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