复极化后的折射性与I类抗不律性药物引起的导电减速:抗不律性和前不律性作用
P F Kirchhof1, C L Fabritz, M R Franz
1Cardiology Division, Veterans National Administration Center, Washington, DC 20422, USA.
Circulation
|July 10, 1998
概括
药物诱导的后反极化折射性 (PRR) 能够防止心室动 (VF). 然而,propafenone可以通过影响导电和波长来促进缓慢的单形心室性心力衰竭 (VT).
科学领域:
- 电子生理学 电子生理学
- 心脏药理学心脏药理学
背景情况:
- 导电阻可以是抗心律失常和前心律失常.
- 药物诱导的反极化后折射性 (PRR) 可能会预防动脉节律失常.
- 研究了propafenone和procainamide的抗心律失常和前心律失常作用.
研究的目的:
- 调查普罗帕芬和普罗卡因胺对心脏电生理学的影响.
- 为了确定这些药物的抗不律性或前不律性后果.
- 评估后反极化折射性在药物诱导的心律失常症中的作用.
主要方法:
- 使用了隔离的兰登多夫透的子心脏.
- 记录了单相动作潜力 (MAP) 和心电图.
- 在药物注射之前和之后,通过电刺激诱导了心室低心率 (VT) 和心室动 (VF).
主要成果:
- 芬和普罗卡因胺都延长了作用潜力的持续时间,并诱导了PRR.
- 普罗卡因胺减少了70%的VF诱导性,而芬消除了VF.
- 普罗帕芬显著减缓了导电和缩短了波长,导致57%的爆发刺激中引发了静脉动.
结论:
- 药物诱导的PRR有效地防止心室动 (VF).
- 尽管能预防静脉炎症,但可促进缓慢单态静脉炎症.
- 根据使用情况的导电减速和波长缩短由烯可能是VT促进的基础.
相关概念视频
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