异体缩期间心肌加速:与收缩率的关系
Erik Lyseggen1, Stein Inge Rabben, Helge Skulstad
1Institute for Surgical Research and Department of Cardiology, Rikshospitalet University Hospital, Oslo, Norway.
Circulation
|March 9, 2005
概括
肌肉心脏同流体加速 (IVA) 不能可靠地反映区域心肌收缩性. 这一测量是负载依赖的,可能表明晚期透支事件而不是缺血期间的收缩性.
科学领域:
- 心脏病学 心脏病学
- 生理学 生理学 生理学
- 生物医学工程 生物医学工程
背景情况:
- 在同位体体缩期间的中枢环加速被提出作为全球左心室 (LV) 收缩率的负载独立指数.
- 这项研究旨在确定心肌异体体积加速 (IVA) 是否反映区域收缩性.
研究的目的:
- 为了研究心肌异体加速 (IVA) 和区域左心室 (LV) 收缩性之间的关系.
- 为了评估IVA的负载依赖性.
- 评估IVA在缺血期间检测区域性心肌功能障碍方面的实用性.
主要方法:
- 在麻醉狗中使用组织多普勒成像 (TDI) 和声微镜测量LV压力,心肌长轴速度和IVA.
- 操纵全球LV收缩性 (dobutamine) 和预负载 (体积负载).
- 通过减少左前下垂冠状动脉的流量来诱导区域性心肌缺血.
主要成果:
- 多布他胺同时增加了IVA和LVdP/dtmax.
- 体积负荷降低了IVA,但没有改变LV dP/dt (最大) 或区域收缩性.
- 区域性缺血抑制了区域功能,而IVA保持不变.
- 通过TDI和声微波测量对IVA进行测量,结果一致.
结论:
- 峰值IVA没有显示与区域心肌收缩性有一致的关系.
- 峰值IVA显著依赖负载.
- 峰值IVA并没有反映出缺血期间心肌功能受损.
- 峰值IVA可能受到晚期透析事件和壁振荡的影响,限制了其在评估区域心肌功能时的使用.
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