The windkessel model

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– – – – – THE WINDKESSEL MODEL A model for the heart and the systemic arterial system. In particular, it relates the Arterial Pressure and the incoming blood flow into the aorta, representing the load undertaken by the heart during the cardiac cycle. Its importance comes from the modeling of the mechanism that allows a continuous flow even at very low pressure during diastole, since this is the only moment when the hart can be nourished. It can be relevant in the analysis of the effects of vasodilator or vasoconstrictor drugs or in the development of mechanical hearts and heart-lung machines, for instance. It relates: blood pressure blood flow in the aorta and characterizes: arterial compliance peripheral resistance of the valves the inertia of the blood flow The Windkessel Model is analogous to the Poiseuille’s Law for a hydraulic system. It describes the cardiac system as a closed hydraulic circuit that contains a water pump connected to a chamber, filled with water except for a pocket of air. The flow of blood through the arteries is represented by the flow of fluid through pipes. As it’s pumped, the water compresses the air, which in turn pushes the water out of the chamber. This analogy resembles the mechanics of the heart. ● ● ● ● ● ● The Windkessel model takes into consideration the following parameters while modeling the cardiac cycle: Arterial Compliance: refers to the elasticity and extensibility of the major artery during the cardiac cycle Peripheral Resistance: refers to the flow resistance encountered by the blood as it flows through the systemic arterial system. Inertia: simulates the inertia of the blood as it is cycled through the heart. We assume that: Cardiac cycle starts at systole. The period of the systole is 2/5th of the period of cardiac cycle…