重极化替代揭示了对人类心房的脆弱性
Sanjiv M Narayan1, Michael R Franz, Paul Clopton
1VAMC/Cardiology, University of California-San Diego, 3350 La Jolla Village Dr., San Diego, CA 92161, USA. snarayan@ucsd.edu
Circulation
|June 8, 2011
概括
动作潜力持续时间 (APD) 交替的节拍对节拍的振荡揭示了心房动 (AF) 的动态基质. 与对照组相比,这些替代药物在持续性和性AF患者中更容易发生,而且发生率更低.
科学领域:
- 心脏病学 心脏病学
- 电子生理学 电子生理学
- 心脏节律失常症 心脏节律失常症
背景情况:
- 人类心房动 (AF) 的潜在机制仍然不完全理解,与异常的再极化有关,特别是动作潜能持续时间 (APD).
- 存在一系列的AF脆弱性,从没有AF的个体到患有发和持久形式的个体.
研究的目的:
- 调查假设APD中的节拍对节拍振荡,称为APD替代,有助于AF基质.
- 为了确定APD替代剂是否可以解释不同患者群体对AF的不同易感性.
主要方法:
- 在编程电刺激过程中记录了33名受试者的左和右心房APD (12个持久性AF,13个心房AF,8个对照).
- 节奏在减少周期长度 (600到500毫秒,然后更快,直到AF启动) 进行,以评估APD恢复和替换.
- 分析了APD交替子,复杂振荡和不同节奏率的AF启动之间的关系.
主要成果:
- 在对照组中,APD替代药物表现得显著更快 (周期长度为218±33毫秒),相比之下, Paroxysmal AF (372±72毫秒) 和持久性AF (411±94毫秒) 的患者.
- 在AF患者中,APD替代物以100-120bpm的速度发生,并且独立于APD恢复.
- 在AF之前的复杂振荡,在对照组中也以逐渐更快的速度发生,而不是帕洛西斯马尔AF,而不是持久AF患者.
结论:
- 耳前APD替代物作为AF的动态基质,与对照组相比,在持久性和发热性AF患者中最容易出现较低的比率.
- APD替代品始终在所有观察到的AF发作之前,并且在AF没有启动时缺席.
- 需要进一步的研究,以阐明驱动APD替代体在生理心率附近的细胞机制.
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