几何和耐火期在维持心房的重要性:测试临界质量假设
Gregory D Byrd1, Sandip M Prasad, Crystal M Ripplinger
1Division of Cardiothoracic Surgery, Department of Surgery, Washington University School of Medicine, St. Louis, MO 63110, USA.
Circulation
|September 15, 2005
概括
持续性心房动 (AF) 的概率随着心房组织的大小和更短的有效耐火周期 (ERP) 和波长而增加. 这些发现对于理解AF机制和开发新治疗方法至关重要.
科学领域:
- 心脏电生理学 心脏电生理学
- 节律失常的机制 节律失常机制
背景情况:
- 对心房动 (AF) 的临界质量假设缺乏对组织几何学作用的系统研究.
- 以前的研究还没有确定心房组织特征和AF维持之间的关系.
研究的目的:
- 确定心房组织几何学 (宽度,面积,重量) 和AF之间的关联.
- 研究有效耐火期 (ERP),波长和AF维护之间的关系.
主要方法:
- 隔离的狗心房 (n=20) 被 perfused 和节奏诱导AF.
- 通过射频除进行了组织分割,并测量了ERP和导电速度.
- 计算了波长,并在较小的组织部分评估了AF诱导性.
主要成果:
- AF概率与增加的组织面积,宽度和重量显著相关 (P<0.001).
- 较短的ERP和波长显著与持续AF的概率增加有关 (P<0.001).
结论:
- 持续的AF概率与更大的组织尺寸和更短的ERP和波长有关.
- 这些发现提高了对AF机制的理解,并可能指导未来的干预策略.
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