[A comment on optimal shaped prosthesis for tricuspid valve using an experimental model].

Abstract

The prosthesis for mitral valve has been in use instead of the prosthesis for tricuspid valve, since the latter prosthesis has not at present been available. In view of the shape of tricuspid valve, which is essentially flat in form, it is not good for replacing with the prosthesis for mitral valve which has an almost circular shape because of the difficulties in suturing, and many criticisms on this substitution have been raised. In order to obtain more suitable prosthesis as exactly benefits TVR, we have developed at first an instrument indicating the change of cardiac function occurring in the course of fixing the annulus of tricuspid valve that would undergo the difference in shape from circular to flat, using experimental models throughout, which has eventually led to the exploration of the possible exact shape of a prosthesis of the annulus for tricuspid valve. Our series of experiments proved as conclusion that the annulus of tricuspid valve is more advantageous when fixed with an ellipse of a flattened rate 1.6 compared with any circular ones tested. In view of the left ventricular stroke work, it is apparent that a prosthesis for mitral valve which is circular in shape should not be applied. We emphasize that a prosthesis for tricuspid valve which is ellipse in shape with desired flattened rate of 1.6 should be developed for our future applications.