Structural model of the mitral valve included in a cardiovascular closed loop model Static and dynamic validation

A minimal cardiovascular system (CVS) model including mitral valve dynamics has been previously validated in silico. It accounts for valve dynamics using a second order differential equation to simulate the physiological opening valve law. This second order equation is based on output heart signals and is really difficult to bind with anatomical or physiological parameters, making this model difficult to interpret and to particularise to pathological situations. On the other hand, a simple non-linear rotational spring model implemented to model the motion of mitral valve, located between the left atrium and ventricle has been validated on a literature dataset. A measured pressure difference curve was used as the input into the model, which represents an applied torque to the valve chords. Various damping and hysteresis states were investigated to find a model that best matches reported animal data of chord movement during a heartbeat. This model is based on simple physiological behavior modeling, defining parameters linked with physiological or anatomical data. This research describes a new closed-loop CVS model corresponding to the integration of the simple non-linear rotational spring model to describe the progressive aperture of the mitral valve in the minimal cardiovascular system closed loop model. This new model is proved to fit static and dynamic heart behaviour.