细胞激活的功能解离作为莫比茨II型心房阻塞的机制
M D Gonzalez1, B J Scherlag, P Mabo
1Department of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City.
Circulation
|April 1, 1993
概括
在受损的His-Purkinje系统中,心率增加会在Mobitz II型阻断之前导致细胞解离. 这一块通过减少细胞解离来稳定电活动.
科学领域:
- 心脏病学 心脏病学
- 电子生理学 电子生理学
- 心脏传导系统的心脏传导系统
背景情况:
- 在缺血性His-Purkinje系统中的Mobitz II型心房阻塞机制尚未完全理解.
- 一个新的动物模型允许体内和体外研究这种导电缺陷.
研究的目的:
- 为了研究缺血性His-Purkinje系统损伤的动物模型中的电生理学变化.
- 阐明导致在不同心率下发生莫比茨II型心房阻塞的机制.
主要方法:
- 缺血性损伤是通过前隔膜动脉绑定诱导的狗.
- 房节奏被用于诱导2:1心房静脉阻塞.
- 在体外研究中,同时记录了His捆绑和捆绑分支动作潜力和电图.
主要成果:
- 增加的节奏率导致行动潜力的幅度降低,并在His-Purkinje系统中增加细胞解离.
- 细胞解离频率与行动潜力的幅度减少有很强的相关性.
- 阻塞的位置随着节奏率或外刺激的变化而动态移动.
结论:
- 在缺血性His-Purkinje损伤中,速度增加会在 2:1 阻断之前引起细胞解离.
- 莫比茨II型块通过减少细胞解离提供了更稳定的激活模式.
相关概念视频
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01:30Cardiac Action Potential
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