Two-Element Fractional-Order Windkessel Model to Assess the Arterial Input Impedance

Arterial system is completely coupled with the heart, such that the contractile state of the left ventricle and its produced central blood pressure (the pressure in the aorta) are in tune with the arterial mechanical properties. This study investigates the use of fractional-order capacitor and resistor elements to expose, and estimate the main arterial mechanical properties. We propose a simple two-element fractional-order Windkessel model that is able to capture the real aortic impedance dynamic for different cardiac physiological states. To perform a quantitative validation, in-silico ascending aortic blood pressure and flow database of 3,325 virtual subjects was used. The proposed model provides new simplified tool for "hemodynamic problem" solving, offering a pioneer way for a better understanding of vascular mechanical properties dependency on hemodynamic changes such as arterial viscoelasticity.