左心室节奏减小了透静心室相互作用,允许改善预负荷依赖的缩性表现
R A Bleasdale1, M S Turner, C E Mumford
1Department of Cardiology, Wales Heart Research Institute, Heath Park, Cardiff CF14 4XN, United Kingdom. bleasdalera@aol.com
Circulation
|October 13, 2004
概括
左心室 (LV) 节奏减轻了LV填充的外部约束,改善了心力衰竭患者的有效填充压力和中风体积. 这种机制通过斯特林机制增强心脏输出.
科学领域:
- 心脏病学 心脏病学
- 生物医学工程 生物医学工程
- 心脏衰竭研究研究
背景情况:
- 已知左心室 (LV) 节奏可以改善心力衰竭患者的血液动力学.
- 这种好处的潜在机制包括尽量减少由于心室相互作用而对LV填充的外部约束.
研究的目的:
- 为了调查LV步调减少LV填充的外部约束的假设.
- 量化LV加快对LV填充压力和体积的影响.
主要方法:
- 使用导电导管法同时测量13名心力衰竭患者的LV压力和体积 (NYHA类III/IV).
- 在下静脉塞期间,使用末端腹压压积关系测量LV填充的外部约束,有或没有LV节奏.
主要成果:
- LV 调节显著降低了 LV 填充的外部约束 (P<0.01).
- 有效填充压力增加了4.0mm Hg (P<0.01),导致LV终端透气体积增加10mL (P=0.01).
- 冲击体积增加了11毫升 (P<0.01),伴随着LV冲击工作和最大dP/dt的增加.
结论:
- LV 节奏有效地减少了 LV 填充的外部约束,这是血液动力学改善的关键机制.
- 外部约束的减少增加了有效的填充压力,通过斯塔林机制增加了LV终端透支体积和中风体积.
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