Frequency response of blood vessel wall with atherosclerosis and aneurysm

Frequency and chaotic analysis of pulsatile motion of blood vessel wall related to aneurysm

“…These results show that when an atherosclerosis or an aneurysm progress, periodic pulsatile trajectories of the velocity of blood vessel wall show irregular features, which results in the increase in entropy, S [9,11]. Furthermore, a frequency analysis of pulsatile wave form of the velocity of blood vessel wall was conducted [11], which showed that there are dominant frequency f 1 of low frequency which takes the maximum norm and f 2 of high frequency which takes the extreme value of norm [11]. Furthermore, the former was found to correspond with I * [8][9][10] which estimates the progressive degree of visco-elasticity of blood vessel wall [10] and the latter was found to concern the existence of an aneurysm [11].…”

“…On the basis of the proposed noninvasive diagnostic method using Doppler effect sensor [6,7], one of the authors has conducted analyses of the accelerated response of blood vessel wall during systolic period [6][7][8] and analyses of attractors on the periodic trajectories of pulsatile velocity of blood vessel wall [9,11]. Using results obtained by these analyses, the progressive degree of viscoelasticity (mechanical deterioration) of blood vessel wall and the irregular degree of pulsatile trajectory of velocity of blood vessel walls were quantified by I * [8][9][10][11] and entropy, S [9,11] respectively. Furthermore, a parameter estimating the disturbance of the time averaged synthesis wave form calculated by individual pulsatile wave forms of blood vessel wall, D C was proposed [12] and a noninvasive diagnostic method of atherosclerosis and aneurysm was proposed [12].…”

“…D C [12] is defined the gradient of change of multi fractal dimensions [13]. These results show that when an atherosclerosis or an aneurysm progress, periodic pulsatile trajectories of the velocity of blood vessel wall show irregular features, which results in the increase in entropy, S [9,11]. Furthermore, a frequency analysis of pulsatile wave form of the velocity of blood vessel wall was conducted [11], which showed that there are dominant frequency f 1 of low frequency which takes the maximum norm and f 2 of high frequency which takes the extreme value of norm [11].…”

“…Furthermore, a frequency analysis of pulsatile wave form of the velocity of blood vessel wall was conducted [11], which showed that there are dominant frequency f 1 of low frequency which takes the maximum norm and f 2 of high frequency which takes the extreme value of norm [11]. Furthermore, the former was found to correspond with I * [8][9][10] which estimates the progressive degree of visco-elasticity of blood vessel wall [10] and the latter was found to concern the existence of an aneurysm [11]. In this research, all the methods mentioned above are named VISCOIR (measurement method of viscoelasticity and irregular movement of blood vessel wall).…”

“…Furthermore, the specification of pulsatile frequency and the quantification of disturbance of pulsatile wave form of blood vessel wall are important from the view point of not only the clarification of phenomenological mechanism but also the establishment of noninvasive diagnosis of the blood vessel diseases. In this research, on the basis of previous work conducted by one of the authors [6][7][8][9][10][11][12], more detailed analyses of pulsatile frequency of pulsatile motion of blood vessel wall was conducted and these frequencies were related to the blood vessel diseases.…”