在患有缺血性心脏病的人类附带依赖心肌中,冠状动脉"窃取"和静止的收缩功能之间的关系
G Holmvang1, S Fry, H A Skopicki
1Departments of Medicine (Cardiac Unit), Radiology, and Nuclear Medicine, Massachusetts General Hospital, Harvard Medical School, Boston, USA.
Circulation
|May 20, 1999
概括
冠状动脉盗窃,在腺压力测试期间血液流量下降,与依赖附带的心脏部分的休息收缩功能障碍密切相关. 这一发现表明,冠状动脉显著导致一些心脏病患者的慢性衰竭.
科学领域:
- 心脏病学 心脏病学
- 核心脏病学 核心脏病学
- 缺血性心脏病是一种心脏病.
背景情况:
- 假设附带依赖心肌中的休息异能与冠状动脉停止相关.
- 冠状动脉盗窃是一种现象,在附带依赖区域的高血压期间,血液流量下降.
研究的目的:
- 调查慢性缺血性心脏病患者的静止心肌收缩功能和冠状动脉窃取之间的关系.
- 确定冠状动脉静脉与慢性收缩性损伤中的减少流量储备的作用.
主要方法:
- 使用[13N]氨的正子发射断层扫描 (PET) 用于测量心肌动脉血液流量和流量储备.
- 冠状动脉扫描评估了狭窄的严重程度和附带供应.
- 心声图或对比心室图评估区域壁运动.
主要成果:
- 与"偷窃" (与腺的流量下降) 相关的附带依赖部分与没有偷窃或正常收缩的部分相比显示出更高的静止血流.
- 虽然在通常收缩的细分市场中,流量储备较高,但存在显著的重叠.
- 展示钢材的细分市场几乎始终表现出静止不协同 (22/23),而非钢材细分市场则较少表现出不协同 (24/39).
结论:
- 在腺压力期间心肌动脉血流量下降所识别的冠状动脉窃取与附带依赖部分的休息收缩功能障碍密切相关.
- 冠状动脉窃取似乎是选择患者慢性收缩功能障碍病变的一个重要因素.
- 简单地减少心肌流量储备可能比冠状动脉窃取在导致这些患者慢性收缩功能障碍时不那么重要.
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