STUDIES ON RADIO-OPAQUE POLYMERIC BIOMATERIALS WITH POTENTIAL APPLICATIONS TO ENDOVASCULAR PROSTHESES

A new polymeric biomaterial, which uniquely combines radio-opacity (X- ray visibility) and low thrombogenicity, is described. First, preparat ion, purification, and identification of the essential monomeric build ing block, 2-[2'-iodobenzoyl]-ethyl methacrylate (3), are outlined. Se cond, 3 [GRAPHICS] the synthesis of the biomaterial, a terpolymer with composition MMA:HEMA:3 = 65:15:20 (mole/mole/mole) is described. Thir d, the physico-chemical characteristics of the polymer (e.g. NMR spect roscopy, thermal behaviour) are given. Fourth, the in vitro thrombogen icity of the material was characterized by means of recent test assay. The combined results reveal that the terpolymer is very suitable for prosthetic applications in the cardiovascular system. A new prototype of an endovascular stent, made from the terpolymer, is presented. Sten ts find clinical use in interventional cardiology, in conjunction with percutaneous transluminal coronary angioplasty (PTCA). It is put forw ard that the stent prototype presented herein has, at least in princip le, some advantages over existing (metallic) stents; these advantages are primarily owing to the unique combination of X-ray visibility and haemocompatibility which is presently achieved. (C) 1996 Elsevier Scie nce Limited.