围绕一个固定障碍物在均的异型心室心肌中进行反入激发
J Brugada1, L Boersma, C J Kirchhof
1Department of Physiology, University of Limburg, Maastricht, The Netherlands.
Circulation
|September 1, 1991
概括
组织异质性和过早跳动通过在均的心肌组织中导致与纤维方向平行的导电阻塞来启动回入心室性心跳动 (VT). 这一发现澄清了VT启动机制.
科学领域:
- 心血管生理学心血管生理学
- 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:
- 复发性心室低心率 (VT) 是一种危及生命的心律失常.
- 了解VT启动对于开发有效疗法至关重要.
- 组织异质性和折射性分散与静脉瘤病变产生有关.
研究的目的:
- 调查组织异质性在启动回入心室性心跳动 (VT) 中的作用.
- 为了检查光折度分散对VT启动的影响.
- 阐明在均异型心肌中重新进入静脉瘤背后的机制.
主要方法:
- 使用内心结技术在Langendorff透的子心脏中创建了一种均的异构心室内心环.
- 使用高分辨率映射 (248通道) 来分析心表激活模式.
- 诱导在多个点的早发性心跳,以评估重新进入的静脉动启动.
主要成果:
- 在272个测试点中,在43个点启动了重新进入的VT.
- 导电速度与纤维方向平行 (60厘米/秒) 与垂直 (25厘米/秒) 相比显著更高.
- 单向导电块主要与光纤方向平行发生 (41/43例).
- 折射性分散在块形成中起到了很小的作用 (12/43例).
结论:
- 在均的异型心肌中,重新进入的静脉动是由过早的心跳启动的.
- 过早跳动的刺激效率降低导致与纤维方向平行的偏好导电块.
- 在这个模型中,这个优先区块是重新进入者VT启动的主要机制.
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