Background and aim of the study: In order to prevent prosthetic valve endocarditis (PVE), the implantation of a new silver-coated sewing ring has been introduced to provide peri- and postoperative protection against microbial infection.
Methods: A 56-year-old woman with aortic stenosis had elective replacement with a St. Jude Medical mechanical valve fitted with a silver-coated sewing ring (Silzone). The patient developed early PVE, which necessitated reoperation after one month. Despite a second Silzone prosthesis being implanted, the endocarditis recurred. During a third operation an aortic homograft was implanted, and after six months a fourth operation was performed for a pseudoaneurysm at the base of the homograft, in proximity to the anterior mitral valve leaflet.
Results: The diagnosis of PVE was confirmed by the presence of continuous fever, transesophageal echocardiography and growth of penicillin-resistant Staphylococcus epidermidis from the valve prosthesis.
Conclusion: The implantation of all prosthetic valves is encumbered with a risk of endocarditis. Although silver has bacteriostatic actions, the advantages of silver-coated prostheses in the treatment of this condition have yet to be assessed in clinical trials.