间隙结阻剂在隔离的子心脏中降低了除门而没有改变心室折射率
1Department of Medicine, St Michael's Hospital, University of Toronto, Toronto, Ont, Canada.
Circulation
|September 26, 2001
概括
间隙结阻剂如16-DSA和1-heptanol显著降低除门 (DFT) 和心室动周期长度 (VFCL) 的分散. 相比之下,利多卡因增加了DFT,尽管对传导速度有类似的影响.
科学领域:
- 心血管电生理学 心血管电生理学
- 药理学 药理学是指药理学的学科.
- 医学物理 医学物理
背景情况:
- 重新进入心律不整取决于组织特性,如折射性和导电速度.
- 已知Na(+) 和K(+) 通道阻塞剂对电生理学和除门 (DFT) 的影响,但差距连接阻塞剂的影响不太清楚.
研究的目的:
- 研究隔离心中隔离节阻塞剂 (16-多克酸和1-乙醇) 和通道阻塞剂 (利多卡因) 对除门 (DFT) 和电生理学特性的影响.
主要方法:
- 在给隔离过的子心脏16-多克西尔胆固醇酸 (16-DSA),1-乙醇或利多卡因注射之前和之后,进行了除门 (DFT) 测量.
- 评估了电生理学参数,包括心室动周期长度 (VFCL),QRS持续时间和心室有效耐火期.
主要成果:
- 16-DSA和1-heptanol显著减少了DFT,分别减少了23%和21%. 利多卡因增加了26%的DFT.
- 所有药物都增加了VFCL和QRS持续时间,并减少了VFCL分散. 裂变性未经差距结阻剂改变,但随着利多卡因增加.
- 对照心脏显示DFT或电生理学变量没有显著变化.
结论:
- 通过16-DSA和1-heptanol进行电解,可以减少DFT和VFCL的分散,而不会影响折射性.
- 利多卡因,虽然类似地减缓导电,但增加了DFT,突出了通道阻塞剂对心脏电稳定性的差异性影响.
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