组织不连续性影响传导速度恢复:结构障碍可能促进波浪断裂的机制
Richard Derksen1, Harold V M van Rijen, Ronald Wilders
1Heart Lung Center Utrecht, University Medical Center, Utrecht, Netherlands.
Circulation
|July 16, 2003
概括
结构障碍会造成组织不连续性,扰乱心脏电波传播. 这项研究表明,这些不连续性导致异常的导电速度恢复,这可能解释心脏病中的波折和动.
科学领域:
- 心脏电生理学 心脏电生理学
- 生物物理学的生物物理.
- 细胞心脏病学 细胞心脏病学
背景情况:
- 结构性障碍在促进心波破裂和心肌的作用尚不清楚.
- 导电速度 (CV) 恢复是波浪中断的一个关键因素,其异常与心脏病中心室动有关,特别是在纤维化组织中.
- 结构障碍可能会导致组织不连续性,导致异常的心血管恢复.
研究的目的:
- 为了研究由结构障碍引起的组织不连续性导致异常导电速度恢复的假设.
- 阐明在组织不连续性的异常心血管恢复背后的细胞机制.
主要方法:
- 模拟组织不连续性使用新生小鼠心脏细胞培养在一个八臂星模式.
- 在多个部位应用过早刺激并记录了细胞外电图和动能.
- 利用电压测量和计算机模拟来分析模拟不连续性的去极化电流.
主要成果:
- 逐渐增加的激活延迟,表明异常的心血管恢复,特别是在组织不连续性观察到.
- 激活延迟在距离恒星中心的不连续性 (3.13 ms/10 ms) 与近距离 (0.81 ms/10 ms) 相比显著更大.
- 电压和模拟显示,脱极化电流的双相,长时间的激活和延迟的失活导致了观察到的延迟.
结论:
- 已被证明,组织不连续性会导致异常的导电速度恢复.
- 异常恢复是由于初始缓慢激活后激活的快速增加,并在不连续性处延迟脱极化电流的失活.
- 这些发现提供了结构性障碍,异常的心血管恢复和心律失常 (如动) 的可能性之间的机制联系.
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