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Mechanical Control of Relaxation Using Intact Cardiac Trabeculae
Published on: February 17, 2023
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在心力衰竭中,肌肉代谢反射控制左心室缩功能,减少排气分数
Natasha G Boyes1, Michael D Nelson2, Alberto Palmero Canton2
1College of Kinesiology, University of Saskatchewan, Saskatoon, Saskatchewan, Canada.
Journal of applied physiology (Bethesda, Md. : 1985)
|June 22, 2023
概括
患有心力衰竭和减小射出分数 (HFrEF) 的患者在肌肉代谢反射激活 (MMA) 期间表现出减小的中风体积和心率增加,表明收缩储备减少. 在MMA期间,HFrEF患者的外周血管收缩仍然是正常的.
科学领域:
- 心血管生理学心血管生理学
- 心脏衰竭研究研究
背景情况:
- 减少喷射分数 (HFrEF) 的心力衰竭的特征是过度的交感兴奋和改变对肌肉代谢反射激活 (MMA) 的反应.
- 在HFrEF患者中,对MMA的左心室 (LV) 反应尚不清楚.
研究的目的:
- 在使用心脏磁共振成像 (MRI) 的HFrEF患者中MMA期间调查LV功能.
主要方法:
- 对13名HFrEF患者和18名对照患者进行了心脏MRI,这些患者在休息和MMA期间进行了心脏MRI (同位手握,随后是循环阻塞).
- 测量了LV中风体积指数 (SVi),末性体积指数 (ESVi),末性体积指数 (EDVi) 和全球纵向应变 (GLS).
- 评估了心率,平均动脉压 (MAP),心脏输出和总外周阻力 (TPR).
主要成果:
- 在MMA期间,HFrEF患者的SVi下降,而ESVi和心率增加.
- 在MMA期间,TPR和MAP在HFrEF患者和对照组中同样增加.
- 从休息到MMA,心脏输出,EDVi和GLS在两组中都保持不变.
结论:
- 在MMA期间,HFrEF患者表现出受损的收缩储备,其证据是SVi下降和心率增加,尽管保持心率输出和TPR的类似增加.
- 这些发现突显了HFrEF中对同情激活的异常LV反应.
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