Parameterized real operations based model for heart's valves with aortic stenosis

Abstract

This work proposes a valve model that uses cardiac cycle phases and the flow control in order to model a closer representation of their operation based on its shape and values of the blood flow through the valve to study some dysfunctions such as aortic stenosis and how these affect cardiovascular dynamics. This dynamic model uses the 3 phases of a real valve operation; quick opening, slow closing, and quick closing, the shape for each phase is possible to simulate different slopes in the systolic and diastolic stages, and phase timing is coupled to the heart rate. Additionally one can use parameters to represent different hearts sizes. The valve model was implemented in VHDL-AMS for the electrical analog circuit replacing diodes. To simulate dynamic blood flow, the model was implemented in VENSIM, which allow for generation of blood flow velocity profiles and volumes. The simulation results present values in the reference ranges for a normal performance of the heart. This model will be helpful for independent valve's parameters change, so that each heart valves can be represented, also giving medical personnel to simulate several conditions such as the aortic stenosis.