Mechanical model of net reinforced blood vessel

The mechanical behaviour of a blood vessel, reinforced by a net prosthesis firmly connected to the internal wall of the arteria is studied in this art icle. The main aim of the net prosthesis insertion is to stop or at least s low down the progressive deformation of the wall owing to the progressive d egeneration of the elastic fibers in the aneurysmatic aorta. The analytical approach is performed introducing some simplifying assumptions: from the g eometrical point of view, the blood vessel is modelled as a cylindrical tub e reinforced by a prosthesis net with rectangular mesh directed along the m ain axis and, from the mechanical point of view, the artery wall is suppose d to be an isotropic membrane with linear elastic constitutive law. At the current stage the entire blood pressure load is assumed to be carried only by the transverse rods of the prosthesis net, disregarding the mechanical c ontribution due to the longitudinal ones. The structural problem is solved following the hypothesis of small strains but large displacements. Besides the simplified analytical approach a more detailed finite element model is set up. The three fundamental layers along the cross-section of the aorta a re described to obey a non-linear stress-strain relationship. The prelimina ry results obtained seem to encourage deeper investigations both for the su rgical and the mechanical aspects. (C) 1999 Elsevier Science Ltd and Civil- Comp Ltd. All rights reserved.