在患有严重左心室缩症的狗中,血液动力学机制负责降低心下冠状动脉储备
L Hittinger1, I Mirsky, Y T Shen
1Department of Medicine, Harvard Medical School, Brigham & Women's Hospital, Boston, Mass, USA.
Circulation
|August 15, 1995
概括
左心室缩 (LVH) 中心下冠状动脉储备的减少主要是由于压力力等血液动力学因素,而不仅仅是结构变化. 降低这些力量在LVH狗恢复冠状动脉流动,支持这一结论.
科学领域:
- 心血管生理学心血管生理学
- 心脏缩研究研究 心脏缩研究
- 冠状动脉血液流动动力学
背景情况:
- 左心室缩 (LVH) 的特征是心下冠状动脉储量减少.
- 底层机制,无论是血液动力学还是结构性的,仍在争论中.
研究的目的:
- 调查血液动力学或结构因素是否主要是导致 LVH 下心脏冠状动脉储量减少的原因.
- 区分改变墙壁应力与内在结构变化的作用.
主要方法:
- 研究了10只通过大动脉带带诱导的LVH有意识的狗.
- 评估冠状动脉血流和心肌壁压力在接近最大的血管扩张与腺.
- 操纵预加载改变LVH壁应力在LVH狗的子组.
主要成果:
- 在LVH狗中,腺注入导致心下血流量增加较小,心下/心上比率下降较大.
- 在LVH狗的血管扩张期间,LVH壁应力仍然很高.
- 在LVH犬中减少LV壁应力使子内心/表心比率和子内心血流正常化.
结论:
- 血液动力学因素,特别是压力,显著导致 LVH 中心下冠状动脉储量减少.
- 仅仅是结构变化并不能完全解释严重的LVH冠状动脉储备的减少.
- 调节血液动力学力可以恢复 LVH 中的冠状动脉流量储备.
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