Thubrikar M J, Deck J D, Aouad J, Chen J M
Atherosclerosis. 1985 Jun;55(3):299-311. doi: 10.1016/0021-9150(85)90108-x.
Topographic distribution of atherosclerotic lesions of the aortic valve was investigated in rabbits on a 2%-cholesterol-enriched diet and related to distribution of intramural stress in the valve. Initially the lesions appeared at the base of the leaflet on the aortic face and with time spread further out into the leaflet and up the wall of the aortic sinus. In the leaflet, the lesion occurred only in the pressure-bearing part and was primarily composed of a mass of foam cells. By 10 weeks primary fatty plaques were still confined to the aortic face but fibroblasts within the leaflet had also taken up fat. Even after 33 weeks, the atheromatous plaque had not spread beyond the pressure-bearing part of the leaflet. From silicone rubber casts of the valve it was observed that only part of the leaflet was under pressure and the remaining leaflet sustained no pressure gradient. The maximum intramural stress occurred during diastole on the pressure-bearing part. In systole, the blood flow produced shear stress on the entire leaflet. Hence, occurrence of atherosclerotic lesions only in the area of maximum intramural stress suggests that intramural stress and not shear stress plays an important role in accelerating the process of atherosclerosis.
对食用富含2%胆固醇饮食的兔子的主动脉瓣动脉粥样硬化病变的地形分布进行了研究，并将其与瓣膜壁内应力的分布相关联。最初，病变出现在瓣叶主动脉面的基部，随着时间的推移，病变进一步扩散到瓣叶并向上延伸至主动脉窦壁。在瓣叶中，病变仅发生在承受压力的部分，主要由大量泡沫细胞组成。到10周时，原发性脂肪斑块仍局限于主动脉面，但瓣叶内的成纤维细胞也摄取了脂肪。即使在33周后，动脉粥样斑块也未扩散到瓣叶承受压力部分之外。从瓣膜的硅橡胶铸型观察到，只有部分瓣叶承受压力，其余瓣叶没有压力梯度。最大壁内应力发生在舒张期承受压力的部分。在收缩期，血流在整个瓣叶上产生剪切应力。因此，动脉粥样硬化病变仅发生在最大壁内应力区域，这表明壁内应力而非剪切应力在加速动脉粥样硬化进程中起重要作用。
