The effect of mitral annuloplasty on left ventricular regional diastolic function: a finite element model

The surgical procedure of mitral valve repair is often accompanied by the insertion of a semirigid or flexible annular ring. An important effect of the insertion of small rings is a major reduction of the chamber volume and then a better ventricular performance. To evaluate this effect, a finite element model of the left ventricle has been developed. The geometry of the 3D ventricular structure has been modelled with a truncated ellipsoid. The diastolic mechanical properties of the ventricular walls have been modelled by means of a nonlinear isotropic hyperelastic material; the parameters of the constitutive equations have been chosen on the basis of the expected end diastolic pressure-volume relations. The simulations showed a reduction in the end diastolic volumes with an increase in diastolic wall stress in the equatorial and basal regions. The results suggest that a tailored annuloplasty results to be more effective.