改变填充模式对透静压力-体积曲线的影响
T J Fraites1, A Saeki, D A Kass
1Department of Medicine, The Johns Hopkins University, Baltimore, Md 21287, USA.
Circulation
|January 7, 1998
概括
心脏填充的方式会影响由于粘性弹性的心室压力. 改变早期到晚期填充比率 (E:A) 可以显著影响终端透缩压,可能缓解放松或体积变化的效应.
科学领域:
- 心血管生理学心血管生理学
- 腹腔病理学 腹腔病理学 腹腔病学
- 心脏的生物机械特性
背景情况:
- 早期到晚期的心室填充比率 (E:A) 是扩张功能的一个关键指标.
- 心肌粘弹性可以影响室内压力,可能与填充模式相互作用.
研究的目的:
- 为了研究透缩填充模式如何调节室内压力.
- 为了测试填充反可以缓和延迟放松和体积负荷对透缩压力的影响的假设.
主要方法:
- 通过使用伺服来控制排气和填充,研究了隔离的血液透的狗左心室.
- 在不同的预负载下,操纵透缩填充模式以达到特定的E:A比率 (3:1, 1:3, 1:1).
主要成果:
- 早期填充 (E:A=3:1) 显示了随着粘度的增加,扩张压的增加,与放松时间常数成比例.
- 这种粘度-压力依赖性随着E:A比率的降低而减少.
- 较高的E:A比率导致了相似体积的较低比率相比显著较低的终端透缩压.
结论:
- 扩张性填充模式通过粘性弹性直接影响早期和晚期扩张性腔压力.
- E:A比率的变化可以调节诸如延迟放松或增加预负荷等因素对透气压升高的直接影响.
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