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在人类自主神经系统阻塞期间QT间隔的调节
André Diedrich1, Jens Jordan, John R Shannon
1Autonomic Dysfunction Center, Vanderbilt University, Nashville, Tenn. 37232-2195, USA. andre.diedrich@vanderbilt.edu
Circulation
|October 23, 2002
概括
使用三甲的自主阻塞在健康个体和自主功能障碍患者中延长了QT间隔. 这表明自主神经系统显著影响心脏再极化.
科学领域:
- 心脏病学 心脏病学
- 自主神经系统研究 自主神经系统研究
- 临床电生理学 临床电生理学
背景情况:
- 自主神经系统在调节 QT 间隔中的作用受到争议.
- 之前使用联合甲醇和氨酸的研究产生了相互矛盾的结果.
- 银河节阻塞提供了一种替代方法来评估QT间隔的自主影响.
研究的目的:
- 为了研究质阻塞对QT间隔的影响.
- 为了比较正常人,多系统缩 (MSA) 患者和纯自主衰竭 (PAF) 患者的自主功能和QT间隔延长.
主要方法:
- 在10名正常志愿者,9名MSA患者和8名PAF患者中,以增加剂量 (0.5-10毫克/分钟IV) 输注三甲.
- 监测心率,心率变化 (HRV) 光谱,QT 间隔和血压.
- 用巴泽特公式 (QTc) 校正QT间隔以应对心率.
主要成果:
- 在PAF患者中,基线QTc延长 (465±8毫秒) 和HRV非常低.
- 在正常受试者中,三甲剂量依赖于延长QTc (至469±7毫秒),并取消HRV.
- MSA患者显示QTc延长 (至463±7毫秒),HRV降低,RR间隔没有显著变化.
结论:
- 节阻塞在正常人中延长了QT间隔,持续时间与PAF患者相似.
- 在PAF患者中阻断残留自主音调进一步增加了QT间隔的长度.
- 与PAF患者相比,MSA患者在关节阻塞期间表现出更大的残留交感声调和更显著的QT间隔延长.
关键词:
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