在神经介导昏迷之前的左心室几何和功能
1Department of Medicine, Division of Cardiology, The New York Hospital-Cornell Medical Center, New York, NY 10021, USA.
Circulation
|February 23, 2000
概括
神经介导性并不是由增加的左心室 (LV) 收缩性引起的. 在直立倾斜时减少的LV功能和体积与昏迷患者的倾斜表测试反应有关.
科学领域:
- 心脏病学 心脏病学
- 身体生理学 身体生理学
背景情况:
- 神经介导的昏迷与左心室 (LV) 分数缩短 (FS) 在倾斜测试期间的增加有关.
- 这表明LV机械受体刺激导致反射低血压,但FS受后负荷和前负荷的影响,而不仅仅是收缩性.
研究的目的:
- 为了研究LV收缩在神经介导昏迷中的作用.
- 为了比较 LV 性能指标,对患者进行末性应激 (ESS) 校正,这些患者的倾斜表测试反应呈阳性和阴性.
主要方法:
- 心声图被用于评估21名患者的LV表现,这些患者在仰卧和直立倾斜姿势期间出现了无法解释的昏迷.
- 在倾斜阳性和倾斜阴性组之间比较了LV测量,包括冲击体积,FS和应力校正的中壁缩短.
主要成果:
- 在仰卧的位置,两组都表现出相似的LV性能.
- 在直立倾斜时,倾斜阳性组表现出较低的中风体积,减少压力纠正的中壁缩短,并降低内心FS.
- 倾斜阳性组在倾斜期间早期也显示出ESS和FS的较大减少.
结论:
- 在初始垂直倾斜过程中减少的末压力 (ESS),LV体积和腔室功能与昏迷患者的积极倾斜反应相关.
- 这些发现表明,LV超收缩性或增加的缩壁应力不会通过LV机械受体激活引发神经介导的.
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