用双相波形进行除的强度-持续时间和成功概率曲线
S A Feeser1, A S Tang, K M Kavanagh
1Department of Medicine, Duke University Medical Center, Durham, N.C. 27710.
Circulation
|December 1, 1990
概括
双相波形比单相脉冲在除方面更有效. 这项研究表明,双相波形的有效性取决于倾斜,这表明除了第二阶段之外还有多种除机制.
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
- 电气工程 电气工程 电气工程
背景情况:
- 双相波形越来越多地用于除,因为它们的效率比单相脉冲更高.
- 两相波形的增强有效性背后的精确机制仍然不完全理解.
- 了解这些机制对于优化除策略和设备设计至关重要.
研究的目的:
- 用双相截断指数波形来研究除的机制.
- 为了比较单相脉冲和双相脉冲在不同持续时间和幅度的除功效.
- 阐明波形倾斜和第二阶段特征在除成功中的作用.
主要方法:
- 为单相和双相波形生成强度-持续时间和百分比成功曲线.
- 对于具有不同阶段持续时间的高和低倾斜双相波形,确定了除门.
- 百分比成功曲线是通过改变二相波形第二阶段的振幅来构建的.
主要成果:
- 双相波形的除功效最初有所改善,然后下降,随着第二相持续时间或振幅的增加,再次得到改善.
- 对于 >= 14 msec 的脉冲,高倾斜双相波形的第二相值电压超过了同等持续时间的单相脉冲的电压.
- 波形倾斜显著影响除功效,表明复杂的潜在机制.
结论:
- 双相除的有效性不仅仅归因于第二阶段刺激心脏.
- 至少有两种不同的机制有助于双相除:一种由较短的第二阶段,另一种由较长或更高幅度的第二阶段.
- 双相波形的倾斜程度是影响除成功的关键因素.
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