Atkins Samantha K, Sucosky Philippe
Samantha K Atkins, Philippe Sucosky, Department of Aerospace and Mechanical Engineering, University of Notre Dame, Notre Dame, IN 46556, United States.
World J Cardiol. 2014 Dec 26;6(12):1227-33. doi: 10.4330/wjc.v6.i12.1227.
The bicuspid aortic valve (BAV) is the most common form of inheritable cardiac defect. Although this abnormality may still achieve normal valvular function, it is often associated with secondary valvular and aortic complications such as calcific aortic valve disease and aortic dilation. The clinical significance and economic burden of BAV disease justify the need for improved clinical guidelines and more robust therapeutic modalities, which address the root-cause of those pathologies. Unfortunately, the etiology of BAV valvulopathy and aortopathy is still a debated issue. While the BAV anatomy and its secondary complications have been linked historically to a common genetic root, recent advances in medical imaging have demonstrated the existence of altered hemodynamics near BAV leaflets prone to calcification and BAV aortic regions vulnerable to dilation. The abnormal mechanical stresses imposed by the BAV on its leaflets and on the aortic wall could be transduced into cell-mediated processes, leading ultimately to valvular calcification and aortic medial degeneration. Despite increasing evidence for this hemodynamic etiology, the demonstration of the involvement of mechanical abnormalities in the pathogenesis of BAV disease requires the investigation of causality between the blood flow environment imposed on the leaflets and the aortic wall and the local biology, which has been lacking to date. This editorial discusses the different hypothetical etiologies of BAV disease with a particular focus on the most recent advances in cardiovascular imaging, flow characterization techniques and tissue culture methodologies that have provided new evidence in support of the hemodynamic theory.
二叶式主动脉瓣（BAV）是最常见的遗传性心脏缺陷形式。尽管这种异常仍可能实现正常的瓣膜功能，但它通常与继发性瓣膜和主动脉并发症相关，如钙化性主动脉瓣疾病和主动脉扩张。BAV疾病的临床意义和经济负担证明需要改进临床指南和更有效的治疗方式，以解决这些病变的根本原因。不幸的是，BAV瓣膜病和主动脉病变的病因仍是一个有争议的问题。虽然BAV的解剖结构及其继发性并发症在历史上一直与共同的遗传根源相关，但医学成像的最新进展表明，在容易钙化的BAV瓣叶附近和易发生扩张的BAV主动脉区域存在血流动力学改变。BAV对其瓣叶和主动脉壁施加的异常机械应力可能会转化为细胞介导的过程，最终导致瓣膜钙化和主动脉中层退变。尽管越来越多的证据支持这种血流动力学病因，但要证明机械异常在BAV疾病发病机制中的作用，需要研究施加在瓣叶和主动脉壁上的血流环境与局部生物学之间的因果关系，而这一点目前尚缺乏。这篇社论讨论了BAV疾病的不同假设病因，特别关注心血管成像、血流特征技术和组织培养方法的最新进展，这些进展为支持血流动力学理论提供了新证据。
