左心室壁加厚机制的异质性
Allen Cheng1, Tom C Nguyen, Marcin Malinowski
1Department of Cardiovascular and Thoracic Surgery, Stanford University School of Medicine, Stanford, CA, USA.
Circulation
|July 30, 2008
概括
静脉纤维缩短在左心室 (LV) 均,但心肌板动态的区域差异显著影响LV壁的加厚. 了解这些机制对于心脏治疗至关重要.
科学领域:
- 心血管生理学心血管生理学
- 心脏机械学 心脏机械学
- 生物医学工程 生物医学工程
背景情况:
- 心肌纤维形成了对左心室 (LV) 功能至关重要的膜 (叶片).
- 缩壁的加厚是由纤维缩短,层状延伸,加厚和剪切驱动的.
- 这些机制的区域差异仍然不太清楚.
研究的目的:
- 研究促使缩性 LV 壁厚化的机制的区域变异性和跨壁分布.
- 为了区分板材延长,加厚和剪切在不同LV区域的作用.
主要方法:
- 在绵羊中使用放射性不透明标记物来追踪心肌组织的4D动态.
- 测量了心表,心中壁和内心水平上的缩应变 (周围,纵向,辐射).
- 使用定量组织学转换的菌株数据来确定表格动态的跨壁贡献.
主要成果:
- 与横向赤道区域 (1.6-1.9倍) 相比,缩壁的厚度在前基底区域显著增加.
- 缩纤维缩短在所有跨度深度和区域都是一致的.
- 板材加厚,延伸和剪切对墙壁加厚的贡献因地区和深度而异.
结论:
- 板材动态的区域差异,而不是纤维缩短,解释了缩LV壁厚度的变化.
- 心肌板架构在放大纤维缩短以产生区域墙壁加厚方面发挥着关键作用.
- 未来的心脏干预必须考虑心肌细胞收缩与跨壁架构一起进行有效治疗.
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