Use of mitral homograft to support a mechanical valve prosthesis: A feasible solution for recurrent mitral valve dysfunction

Abstract

CLINICAL SUMMARY A 54-year-old man with a diagnosis of mitroaortic endocarditis caused by methicillin-sensitive Staphylococcus epidermidis underwent mitral and aortic valve replacement (CarboMedics 31 mm and 23 mm; CarboMedics Inc, Austin, Tex) and received cloxacillin benzathine (INN cloxacillin) and gentamicin for 7 days, followed by cloxacillin for 5 weeks. Results of valve cultures and control blood cultures at 15 and 60 postoperative days were negative. Six months later, a first reoperation was performed because of endocarditis of both prostheses. An aortic homograft substituting the aortic root and a new CarboMedics prosthesis were implanted. Results of valve cultures, blood cultures with prolonged incubation, and serologic tests for Coxiella, Brucella, Mycoplasma, and Bartonella infections were negative. Combined treatment with vancomycin, gentamicin, and rifampin (INN rifampicin) for 2 weeks was administered, followed by vancomycin and rifampin for 4 weeks. Results of blood cultures were negative. Six months later, a second reoperation was needed because of dehiscence of the mitral prosthesis in the mitroaortic junction and macroscopic appearance of endocarditis. A new CarboMedics prosthesis was inserted. Vancomycin and rifampin were empirically administered during 6 weeks and gentamicin during 2 weeks. All cultures and serologic tests were unrevealing. Three months later, a third prosthetic valve replacement for infective endocarditis was performed. Results of cultures and serologic tests were negative. The patient received linezolid and rifampin for 6 weeks because of poor tolerance of vancomycin. Six months later, the patient underwent a fourth reoperation, this time for acute pulmonary edema and severe mitral