皮质肌肉功能障碍的缺血性 mitra 反的悖论性下降:从三维和对比心声谱与应变率测量的洞察力
E Messas1, J L Guerrero, M D Handschumacher
1Cardiac Ultrasound Laboratory, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA.
Circulation
|October 17, 2001
概括
皮质肌肉 (PM) 功能障碍可以通过改善叶片合并来悖论地减少缺血性 mitrale regurgitation (MR). 这一发现突出了MR的几何因素,并提出了新的治疗方法.
科学领域:
- 心血管生理学心血管生理学
- 心脏机械学 心脏机械学
- 医疗成像医学成像
背景情况:
- 缺血性额头吐 (MR) 传统上被归因于乳头肌 (PM) 收缩功能障碍.
- 目前的理论侧重于左心室 (LV) 扭曲,导致尖顶叶片结合.
- 然而,PM功能障碍仍然是常见的诊断,促使重新评估其作用.
研究的目的:
- 调查一个假设,即PM收缩功能障碍可以矛盾地减少MR.
- 通过几何变化探索下层基础缺血在调节MR中的作用.
主要方法:
- 在7只绵羊中,封闭了近端环流循环,维持了PM perfusion.
- 使用3D心声学测量了传单绑定距离和LV喷射体积.
- 通过从LV喷射体积减去LV外流来评估MR.
主要成果:
- 由于PM尖端收缩,单独诱导的较低缺血症轻度至中度MR (25.2+/-2.8%的反分数).
- 添加PM缺血减少了MR (5.2+/-0.3至1.4+/-0.3毫升) 和绑定距离.
- 颗粒物应变速率从收缩转向延长,降低了叶片的张.
结论:
- 矛盾的是,PM收缩功能障碍可以在基底缺血中降低MR.
- 这种效应是通过减少小册子连接和改进的共作用来实现的.
- 在缺血性MR机制和潜在的治疗策略中,几何因素至关重要.
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