Conference Paper

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

Inst. of Clinical Physiol., CNR, Pisa
DOI: 10.1109/CIC.2000.898595 Conference: Computers in Cardiology 2000
Source: IEEE Xplore

ABSTRACT 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

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