New biolized polymers for cardiovascular applications

The substitution of damaged natural vessels of large diameter, (>8 mm) seems actually satisfactory solved by the use of vascular prostheses made of woven or knitted Dacron or Teflon fabrics, which allow the formation, inside the graft, of a tissue (pseudo-intima) which is structurally very similar to that of natural artery. Commercially available synthetic polymeric prostheses, frequently fail when the internal diameter is less than 8 mm. however, Many factors contribute to their failure: thrombogenicity, compliance different to that of natural vessel, poor tissue ingrowth or, on the contrary, tissue hyperproliferation. During the last few years we studied the synthesis and characterization of new potentially hemocompatible thermoplastic elastomers, mainly polyurethanes and polyurethane-ureas.