由宫外焦点引起的阳性心房/心房动的发起机制:一个模拟研究
Yunfan Gong1, Fagen Xie, Kenneth M Stein
1Department of Medicine, Division of Cardiology, Weill Medical College of Cornell University, New York, NY 10021, USA. yfgong@hotmail.com
Circulation
|April 11, 2007
概括
在心房的宫外焦点可以通过动态再极化分散启动心房动/心肌动. 肺静脉焦点为这种心律失常创造了最大的脆弱窗口,这表明它在启动中起着关键作用.
科学领域:
- 计算电生理学 计算电生理学
- 心脏电生理学心脏电生理学
- 节律失常的发生 (arrhythmogenesis).
背景情况:
- 宫外焦点引发阴性心房/ (AFL/AF) 的机制尚不清楚.
- 了解子宫外焦点在AFL/AF中的作用对于开发向疗法至关重要.
研究的目的:
- 通过使用计算建模,研究宫外焦点引发AFL/AF的机制.
- 为了确定宫外焦点位置和离子电流变化的影响,AFL/AF诱导.
主要方法:
- 在一个解剖学上准确的3D心房模型上利用并行计算技术.
- 纳入了心房肌细胞的详细离子电流模型,重点关注L型Ca2+电流 (I(Ca,L)).
- 分析了归还曲线,导电速度和再极化动态.
主要成果:
- 调节I ((Ca,L) 的情况,使恢复曲线更加利,并促进了导电阻和重新进入.
- 观察到动态空间再极化分散,包括不和的替代物.
- 确定了AFL/AF诱导的脆弱窗口,根据焦点位置和时间而有所不同.
- 肺静脉焦点显示出最大的脆弱窗口,导电阻塞位移动.
结论:
- 动态诱导的再极化分散,特别是不和的替代物,是外阴焦点的AFL/AF诱导的基础.
- 宫外焦点位置和时间显著影响重新进入诱导地点和可能性.
- 肺静脉区域是AFL/AF启动的关键区域,因为它的脆弱窗口很大.
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