异步心力衰竭的电生理后果及其通过再同步治疗的恢复
Takeshi Aiba1, Geoffrey G Hesketh, Andreas S Barth
1Johns Hopkins University School of Medicine, Baltimore, MD 21205, USA.
Circulation
|February 25, 2009
概括
心脏再同步疗法 (CRT) 在失同收缩 (DHF) 的心力衰竭中部分恢复离子通道功能和处理. 这提高了动作潜力的持续时间,并可能减少心律失常,有助于CRT.
科学领域:
- 心脏病学 心脏病学
- 电子生理学 电子生理学
- 心脏衰竭研究研究
背景情况:
- 心脏再同步治疗 (CRT) 是一种常见的心力衰竭与异步收缩 (DHF) 的治疗方法.
- 在DHF中CRT的详细电生理效应尚未完全理解.
研究的目的:
- 在犬类模型中研究CRT的电生理后果.
- 检查CRT对离子通道功能,处理和作用电位特征的影响.
主要方法:
- 使用左束枝切除和步调创建了DHF的狗模型.
- 来自对照,DHF和CRT组的细胞使用全细胞补丁进行了研究.
- 定量PCR和西部斑点评估了离子通道和相关蛋白质的mRNA和蛋白质水平.
主要成果:
- DHF降低了关键电流 (I(K1),I(K),I(to)) 和电流 (I(Ca)) 的峰值密度.
- CRT部分恢复了I(K1) 和I(K),并使I(Ca) 振幅正常化,但没有衰变.
- CRT加快了的短暂衰变,增加了侧面肌细胞的振幅,减少了动力潜力的持续时间和早期的脱极化.
结论:
- CRT部分扭转了DHF诱导的离子通道重塑和失调.
- CRT减轻了区域行动潜力持续时间的异质性,可能抑制心律失常.
- 这些电生理学改进可能是CRT所见的生存益处和机械改进的基础.
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