Assessing mechanical properties of the cardiovascular system

Abstract

The elasticity of wall of the arteries plays a significant role in cardiovascular system. Capacitance of the aorta is predicative of cardiovascular events[1]. To get better understanding the function of the cardiovascular system, special attention should be paid to digest the traditional two-element Windkessel model. Because the Windkessel model provides information of cardiovascular function and which may be useful for prevention and diagnosis of hypertension. Our research presents a series of in vitro experimental studies of compliance, peripheral resistance, and pulse waves. In this thesis, several studies have been achieved: 1) a mathematical model for the capacitance of the aorta is derived based upon the conservation of mass, and a specialized test device provided by BDC Laboratories is used to simulate the aorta by employing an arched silicone-rubber tube with a known capacitance. 2) applied and compared arterial compliance determined from blood pressure, arterial compliance determined from PWV, and mechanical capacitance in flexible tubes and animal calf aortae. 3) investigated using sensitivity analysis as the analytical technique to determine parameters which. 4) develop a new technique which based on blood pressure diagram of flexible tubes and animal aortas. In the first study corresponding to chapter five, that the entire blood-pressure state may be plotted on a single blood-pressure diagram using three nondimensional groups. This diagram illustrates the impact of altering the capacitance and ejection period on the pulse pressure that exists within the aorta. In the second study corresponding to chapter six, the sensitivity analysis that has been used to figure out sensitivity coefficients with the largest magnitude is based on the most sensitive parameter that can be adjusted if we want to alter a pressure. In the third study corresponding to chapter seven, arterial compliance determined from blood pressure is more straightforward approach than arterial compliance determined from PWV to measuring the arterial stiffness. By that allowing hypertension to be managed. In the last study corresponding to chapter seven, it is figured out that total cardiovascular capacitance plays a significant role in determining the risk factors for cardiovascular disease, and the systolic and diastolic pressures during the cardiac cycle. In addition to cardiovascular capacitance other parameters that contribute to creating blood pressure include total peripheral resistance, stroke volume, ejection period, and heartrate. In conclusion, this research, combined with additional support may permit the realization for measuring arterial stiffness in the home setting. This research may make significant paradigm changes in prognosis and diagnosis of arterial stiffness and other cardiovascular events.