诱导电异质性会损害心室除:一种特定于区域导电速度减缓的效应
M R Ujhelyi1, J J Sims, A W Miller
1University of Georgia College of Pharmacy, Augusta VA Medical Center, and Medical College of Georgia School of Medicine, Augusta, USA. michael.ujhelyi@medtronic.com
Circulation
|December 22, 1999
概括
导电速度的分散,而不是折射性,增加了除能量需求 (DERs). 利多卡因减缓了导电和增加了DERs,而d-sotalol影响了折射性而不改变DERs,这表明导电速度分散是除功效的关键.
科学领域:
- 心血管生理学心血管生理学
- 电力生理学 电力生理学
- 医疗设备工程 医疗设备工程
背景情况:
- 减振能量需求 (DERs) 对于恢复正常心律至关重要.
- 影响DERs的因素,如电导和折射性,尚未完全理解.
- 了解这些因素可以优化除策略.
研究的目的:
- 调查改变导电速度,折射性和兴奋能力对双相冲击除能量需求 (DERs) 的影响.
- 为了确定这些电特性中的分散是否会影响DERs.
- 阐明除功效背后的机制.
主要方法:
- 24只猪接受了利多卡因,d-sotalol (低剂量和高剂量) 或盐水的区域性心肌输液.
- 在多个心肌部位测量有效耐火周期 (ERP) 和导电速度.
- 评估了除能量需求 (DERs) 和心室动 (VF) 参数.
主要成果:
- 区域性利多卡因输注显著增加了84%的DER,并将传导速度减慢了23-35%,增加了传导速度分散.
- 区域d-sotalol增加了14-17%的ERP和140%的ERP分散,但没有影响DER或传导速度.
- 利多卡因在大多数动物中诱导了心室动 (VF),而d-sotalol则没有;这两种药物延长了VF循环长度并增加了其分散.
结论:
- 区域导电速度减缓及其分散显著增加了DERs.
- 在不改变导电速度的情况下,光折度的扩散不会影响DERs.
- 传导速度的分散似乎是除功效的更关键的决定因素,而不是折射率的分散.
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