Fluid dynamics of the mitral valve: Physiological aspects of a mathematical model

This paper presents a computational method that can be used to study the fluid dynamics of the natural or prosthetic mitral valve in a computer test chamber with contractile muscular walls that model the left side of the heart. Having solved the equations of motion and predicted the performance of the valve, the computer presents the results in terms of flow patterns (streamlines), pressure-contour plots, and graphs of velocity, pressure, flow, tension, and distance as functions of time. Predicted echocardiograms and phonocardiograms are also generated by the computer. These predictions are compared with the results of animal experiments, and the method is used to study the diastolic role of the chordae tendineae, the pathophysiology of mitral valve prolapse syndrome, and the fluid dynamics of pivoting disc valves. Our results support the hypothesis that the chordae have a functional role during diastole. The results also establish a computer model of mitral prolapse, which should be useful in functional studies of that condition, and show that the position of the pivot point and the curvature of the occluder can have a profound effect on the angle of opening of pivoting disc valves. These studies illustrate the applications of the method in physiology, pathophysiology, and prosthetic valve design.