心力衰竭中的血液流动动力学
J K Shoemaker1, H L Naylor, C S Hogeman
1Department of Medicine, Section of Cardiology, Pennsylvania State University College of Medicine, Hershey, PA, USA. kshoemak@gcrc.hmc.psghs.edu
Circulation
|June 15, 1999
概括
心力衰竭 (HF) 患者在运动期间显示肌肉糖解的增加. 在艰苦的运动中,前臂血管导电率降低表明,加强血管收缩有助于高血压患者的疲劳.
科学领域:
- 心血管生理学心血管生理学
- 骨肌肉的新陈代谢
- 心脏衰竭病理生理学 病理生理学
背景情况:
- 心力衰竭 (HF) 中的运动不耐受与血管扩张受损,血管收缩增加和肌肉新陈代谢改变有关.
- 这些因素有助于HF患者在体力活动期间所经历的疲劳.
研究的目的:
- 与健康对照组相比,研究心力衰竭 (HF) 患者对节奏前臂运动的血管和代谢反应.
- 为了检查HF对氧气输送与运动期间吸收的时间过程的影响.
- 评估运动期间血管收缩,特别是HF患者的代谢反射.
主要方法:
- 在9名HF患者和9名对照人群 (CTL) 上使用了两种炼方案.
- 协议1评估了氧气输送和吸收动态.
- 协议2评估了缺血前臂运动期间血管收缩,以唤起代谢反射.
主要成果:
- 与CTL相比,HF患者在4分钟的运动后表现出更高的静脉乳酸盐和H+水平,尽管血液流量和氧气摄入量相似.
- 对缺血性运动的平均动脉压反应在两组之间是可比的.
- 与对照组不同的是,HF患者在缺血运动期间与环境运动相比,在缺血运动期间显示出前臂血流和血管导电率的减少.
结论:
- 在HF中,增加对中度运动的糖溶性代谢反应归因于固有的骨肌肉差异,而不仅仅是血管扩张动力学.
- 在HF中,在艰苦的缺血运动中无法增加前臂血管导电量,这表明增强的血管收缩有助于显著增加力疲劳.
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