Cardiovascular prostheses

Last but not least requirement, artificial arterial substitutes must be able to be connected to the host s vessels using sutures, the only reliable mean surgeons trust (Fig. 2). The connections performed must be stable and blood tight for as long as the prosthesis will remain patent. This last condition has supported the interest of surgeons for vascular prostheses made of woven or non-woven and knitted synthetic fabrics. The following sections give an outline of the different steps that line the evolution of materials for the cardiovascular system, and present some prospective solutions that have been proposed and supposed to improve the performances of these materials. 

Potentiation of the effect of warfarin by danshen (the root of Salvia miltiorrhizd), a widely used traditional Chinese herbal medicine, particularly for cardiovascular complaints, has been described in a 62-year-old man with a mechanical mitral valve prosthesis (159). 

Cardiovascular Blood vessel prosthesis Heart valve Catheter Pacemaker Dacron, Teflon , polyurethane Reprocessed tissue, stainless steel, carbon Silicone rubber. Teflon, polyurethane Polyurethane, silicone rubber, platinum electrodes... 

Fig. 11.1 Cardiovascular prosthesis used for surgical treatment of an aneurism of the aorta in a real patient. Courtesy of Prof Dr. H.-J. Schaefers (Homburg/Saar, Germany).

Sawyer, P.N., Stanczewski, B., and Kirschenbaum, D. 1977. The development of polymeric cardiovascular collagen prosthesis. Artif. Organs 1 83 91. 

Clark RE, Apostolou S and Kardos JL, Mismatch of mechanical properties as a cause of arterial prosthesis thrombosis . Surgical Forum, 1976 27 208-210. HowTV, Mechanical properties of arteries and arterial grafts , in Cardiovascular Biomaterials, G. W. Hastings (ed.). Springer Verlag, New York, 1992 1-35. Hayashi K, Handa H, Nagasawa S, Okumura A and Moritake K, Stiffness and elastic behavior of human intracranial and extracranial arteries , J. Biomech., 1980 19 351-358. 

Matsumoto, H., Kimura, T., Takamatsu, T., Fukada, E., and Saigusa, M. The genesis of thromboresistance in expanded polytetrafluoroethylene venous prosthesis and the similarity of its surface properties with those of the cardiovascular endothelial lining. Artificial Organs. 5 ... 

Okumura N., Nakamura T., Natsume X, Tomihata K., Ikada Y. Shimizu Y. (1994) Experimental study on a new tracheal prosthesis made from collagen-coniugated mesh, tourned of Thoracic (jf Cardiovascular Surgery, 108, 337-45. 

S. Iwai, Y. Sawa, H. Ichikawa, S. Taketani, E. Uchimura, G. Chen, M. Kara, J. Miyake, and H. Matsuda, Biodegradable polymer with collagen microsponge serves as a new bioengineered cardiovascular prosthesis,/. Thorac. Cardiovasc. Surg., 128,472-479,2004. 

Adhesion and colonization of microorganism on the prosthesis (either bone tissue or cardiovascular), mostly occurs during the intervention, which is the main reason why the major infections are of nosocomial origin (hospital acquiring infection). 

The infectious susceptibility of implants remains as a major unsolved problem in the area of implants (29,30). Implants may serve as a route for the entry of an infectious agent or may serve as a preferential site for the deposition of the agent with subsequent growth, embolization if in the cardiovascular system or infiltration into adjacent tissue. In many of these cases, removal of the prosthesis is necessary to achieve a cure. 

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