在左心室功能障碍的人群中,levosimendan对心肌直接影响:力频率和放松频率关系的改变
Michael M Givertz1, Costa Andreou, Chester H Conrad
1Cardiomyopathy Program and Cardiovascular Section, Boston University Medical Center, Boston, Mass, USA. mgivertz@partners.org
Circulation
|March 7, 2007
概括
利沃西门丹是一种敏化剂,在心力衰竭患者中提供轻微的内热和热益处. 它可以改善心和腹功能,而不会改变强力频率或放松频率关系.
科学领域:
- 心脏病学 心脏病学
- 药理学 药理学是指药理学的学科.
背景情况:
- 敏感剂正在被探索为心力衰竭的治疗,但存在关于减弱放松的担忧.
- 莱沃西门丹通过与素C结合来增强肌纤维纤维敏感性,在体外显示出积极的内热和热作用.
- 研究levosimendan对人类心力衰竭的直接影响真实体内心肌是至关重要的.
研究的目的:
- 为了确定levosimendan对心缩和心缩功能在人心左心室功能障碍的体内影响.
- 评估levosimendan的作用是否取决于心率.
主要方法:
- 十名患有非缺血性扩张性心肌病的患者接受了左心室导管治疗和右心房节奏.
- 给出了冠状动脉内levosimendan,在各种心率下测量了内热素 (+dP/dt) 和热素 (Tau) 反应.
- 对照测量是在冠状管内注射盐水时进行的.
主要成果:
- 在一系列心率中,levosimendan以剂量依赖的方式增加了峰值+dP/dt,并降低了tau.
- 单独对心房进行刺激会降低tau,但不会增加+dP/dt.
- 莱沃西门丹并没有改变强力频率或放松频率关系.
结论:
- 用levosimendan对心肌的敏感化在患有左心室功能障碍的人群中提供了温和的内热和热效应.
- 莱沃西门丹对心和腹功能的有益作用不会受到心率变化的调节.
- 药物不会改变人类心肌衰竭的内在力量频率或放松频率动态.
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