[Changes in biomechanical properties of biological and synthetic prostheses]

Arterial compliance which is an expression of the structural properties of the vessel wall is defined as the fractional change in diameter in response to a unit change in pressure. It is likely to play an important role as a predictive parameter for maintenance of arterial reconstruction. Usually, vascular grafts are implanted with an arbitrarily applied longitudinal tension. The current study was designed to evaluate in vitro the effects of longitudinal tension on the dynamic circumferential compliance of different Dacron, Polytetrafluorethylene, Polyurethane and newly developed synthetic vascular grafts as well as arteries and veins. Longitudinal tensions between 0 and 1000 g were applied. Different grafts showed characteristic peak compliance values due to the used graft material, fabrication and extent of tension. Concerning their different compliance-tension profiles two groups of vascular grafts could be differentiated: 1) grafts which develop best compliance values after implementation of longitudinal traction and 2) prostheses which gain optimal biomechanical properties without any traction. There is strong evidence for modulation of compliance by implementation of longitudinal tension which suggests that it is useful to improve long term patency of arterial reconstruction.