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在冷盐水应用期间心下鼓动值分布;探索可逆心律失常抑制
Osamu Saitoh1, Takumi Kasai1, Ayaka Oikawa1
1Cardiovascular Research of Graduate School of Health Sciences, Niigata University School of Medicine, Niigata, Japan.
Pacing and clinical electrophysiology : PACE
|November 16, 2024
概括
通过导管冷盐水灌可以暂时停止心肌信号,有助于找到射频切除的最佳地点. 这种方法对精确的心脏手术非常有前途.
科学领域:
- 心脏电生理学 心脏电生理学
- 最少侵入性心脏外科手术
- 医疗器械技术 医疗器械技术
背景情况:
- 射频 (RF) 除是心律失常的关键治疗方法.
- 精确准废除部位至关重要,特别是在微妙的心脏结构附近.
- 目前用于识别最佳除部位的方法可能需要进一步改进.
研究的目的:
- 通过灌导管来研究冷盐液应用的潜力,以可逆抑制心下肌肉刺激.
- 确定这种方法是否可以帮助识别灵敏心脏区域周围的理想射频 (RF) 能量传递点.
- 评估冷盐水对心肌刺激性的深度依赖性影响.
主要方法:
- 使用开放式灌导管将4°C盐水 (20毫升/分钟) 应用到猪心脏中.
- 测量了心肌温度在表面以下2毫米 (Temp-BS) 和节奏值增加 (%增加-PT).
- 节奏值在不同的深度被评估,使用离析导管附近的电极注入针.
主要成果:
- 冷盐水的应用可逆地抑制了心下肌肉激发,中断了心室节奏捕获.
- 节奏值的增加在心肌表面是最大的,并且随着深度的增加而减少.
- 在2-3毫米深处观察到显著的节奏值增加 (>150%),在6-7毫米深处观察到 (>120%).
结论:
- 冷盐水灌是一种简单,可逆的方法来抑制心下肌肉激发.
- 这种技术显示出在敏感心脏区域预先确定最佳除部位的潜力.
- 为了临床应用,需要进一步的研究和技术开发.
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