在慢性狗模型中,支动心脏诱导的持续性心房动背后的功能机制
R Gaspo1, R F Bosch, M Talajic
1Department of Medicine and Research Center, Montreal Heart Institute and University of Montreal, Quebec, Canada.
Circulation
|December 24, 1997
概括
快速的心房节奏缩短了心房有效耐火期,并减缓了导电,通过改变电性质来促进心房动 (AF). 这些变化,特别是区域异质性,为持续的AF创造了基质.
科学领域:
- 心脏病学 心脏病学
- 电力生理学 电力生理学
- 心脏节律失常症 心脏节律失常症
背景情况:
- 快速心房激活是电力改造的已知触发因素,促进心房动 (AF).
- 通过快速心房激活促进AF的确切机制仍然不完全理解.
- 在狗模型中进行心脏表皮图绘制,用于调查心房电生理学和AF持续时间.
研究的目的:
- 评估快速心房节奏对心房电生理学的时间依赖性影响.
- 确定这些电生理学变化如何影响心房动的持续时间和基质.
- 为了阐明导致持续AF的机制,以响应快速节奏.
主要方法:
- 狗模型接受了快速心房节奏 (400/分钟) 1,7,或42天.
- 脊心映射用于评估心房有效耐火期 (ERP),导电速度和AF周期长度 (AFCL).
- 统计分析包括渐进多线性回归以确定AF持续时间的决定因素.
主要成果:
- 耳前鼓动逐渐增加了AF持续时间.
- 在7天内观察到心房ERP和ERP适应的显著下降.
- 导电速度下降得更慢,最大变化在42天,有助于增加AF持续时间.
- 增加AFCL变异性和AFCL的区域异质性被确定为关键因素.
- 波长和节奏持续时间是AF持续时间的独立决定因素.
结论:
- 快速的心房激活会诱导时间依赖的电力改造,包括降低ERP和导电速度.
- 在AFCL中增加的区域异质性对持续AF的基质有显著的贡献.
- 这些发现表明,AF患者的导电异常和区域异质性可能是心律失常的原因和后果.
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