当冠状动脉血液流量减少时,延长的透静时间分数可以保护心肌输液
1Department of Medical Physics, Cardiovascular Research Institute Amsterdam, Academic Medical Center, University of Amsterdam, The Netherlands.
Circulation
|July 7, 1999
概括
降低冠状动脉血流增加了狗的透析时间分数 (DTF),这表明,当血管扩张受到限制时,心肌氧供应和需求相匹配的调节机制.
科学领域:
- 心血管生理学心血管生理学
- 心肌 perfusion 动力学 在心肌 perfusion 动力学
背景情况:
- 冠状动脉的血液流动对于心肌输液至关重要,特别是在腹痛期间.
- 扩张时间是足够的血液供应到心脏肌肉的关键决定因素.
研究的目的:
- 为了研究冠状动脉血流是否会影响心率恒定的心动静止持续时间.
- 阐明冠状动脉流量和心动静脉时间分数 (DTF) 之间的关系.
主要方法:
- 实验是在麻醉后的,胸部开放的狗身上进行的.
- 通过降低输液压力来操纵冠状动脉血流.
- 在不同压力条件下测量透析时间分数 (DTF) 和冠状动脉流量,包括服用腺和L-NMMA.
主要成果:
- 降低冠状动脉 perfusion 压力显著增加了透静时间分数 (DTF).
- 在较低的 perfusion 压力 (例如 40 mm Hg) 时, DTF 显著增加.
- 在压力降低期间,冠状动脉流量增加,这表明了补偿机制.
结论:
- 冠状动脉的血流调节了透缩时间,特别是在自调节范围以下.
- 这种调节作为一个重要的调节机制,以平衡心肌氧氧气供需.
- 当心脏的血管扩张能力耗尽时,这些发现很重要.
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