在猪最大血管扩张期间,低零流量压力和最小容量对透静冠状动脉压力流量关系的最小电容效应
Circulation
|September 1, 1984
概括
在猪中,血流停止的冠状动脉压力 (Pzf) 接近右心房压力. 这种低的Pzf,不受干预的影响,有助于维持冠状动脉血流,即使在较低的输液压力.
科学领域:
- 心血管生理学心血管生理学
- 血液动力学 血液动力学
- 冠状动脉循环 冠状动脉循环
背景情况:
- 冠状动脉压力-流量关系对于理解心肌输液至关重要.
- 之前在狗身上进行的研究报告说,在最大血管扩张过程中,心血管静脉压高而流量停止 (Pzf).
- 猪中Pzf的行为及其对影响附带流和冠状动脉容量的干预反应的反应并没有得到很好的描述.
研究的目的:
- 测量猪左前下垂冠状动脉 (LAD) 中的Pzf.
- 确定干预对附带流和冠状动脉电容对Pzf.的影响.
- 为了比较猪Pzf与以前报告的狗Pzf值.
主要方法:
- 44只猪在LAD的仪器仪表下进行了研究,用于压力和流量测量.
- 在最大血管扩张 (腺) 期间的部分LAD阻塞被用来构建压力流动关系.
- 干预措施包括短暂的右冠状动脉 (RCA) 阻塞,增加左心室缩压 (LVSP) 和心率增加.
主要成果:
- 在猪的LAD中,晚期透气Pzf明显低于之前在狗中报告的,平均为7.0 +/- 2.2mm Hg,仅略高于右心房压力.
- 平均Pzf为12.1 +/- 3.1mm Hg,也接近右心房压力.
- Pzf保持稳定,在RCA封闭,增加LVSP或心率增加期间没有显著变化,表明Pzf独立于附带流和冠状动脉电容变化.
结论:
- 猪的Pzf总是很低,接近右心房压力.
- 这种低的Pzf保持不论干预改变附带循环或冠状动脉容量.
- 低Pzf是有利的,以确保足够的冠状动脉血流在降低的输液压力.
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