Abstract
It has been pointed out that the hypertension is one of the physical factors which can cause a formation of atherosclerosis and accelerate atherogenesis. The mechanical constriction of vasa vasorum may occur due to abnormally high stresses in arterial walls caused by hypertension and the flow in the vasa vasorum may be impeded. Thus, it may be expected that the supply of nourishment to the arterial wall tissue will be impaired and this may lead to initiating structural degenerations. The purpose of the present paper is to investigate into the deformation of vasa vasorum embedded in an artery and the blood flow conditions in the vasa vasorum in order to examine whether or not above phenomena can occur. The deformation of the model vasa vasorum was analyzed and the relation between hydraulic resistance in arteries deformed by force and the configuration of the arterial cross-section was experimentally examined. The following conclusions were obtained from above analytic and experimental results.
Both arterioles and venules of the vasa vasorum underwent a finite deformation in the same way and the hydraulic resistance in those vessels increased at hypertensive levels of arterial pressure. The increasing rate of the hydraulic resistance, however, was not excessively high and depended on the configurations of the vasa vasorum at the physiological levels. It can be concluded, at present time, that the wall tissue degeneration may slightly be derived from the decrease of blood flow due to the large deformation of the vasa vasorum at hypertensive pressure and there may be little possibility that this wall tissue will develop into atherosclerosis
