Mitral valve prosthesis dehiscence necessitating reoperation. An analysis of the risk factors involved

Between January 1970 and December 1981, a total of 21 reoperations for periprosthetic leak were performed on 20 patients out of 999 with previously implanted prosthetic mitral valves. In most of them reoperations were performed within the first year, since the initial procedure and the leading indications were intractable congestive heart failure or infection of the mitral prosthesis. The mortality rate was 30% and was related to the preoperative cardiac functional status. The preoperative variables significantly related to an increased incidence of dehiscence of the mitral prosthesis necessitating reoperation were a degenerative disease (P = 0.016) or an infective endocarditis (P = 0.0006) of the native valve, both causing mitral regurgitation. Rheumatic disease, type of prosthesis, supra- or subannular insertion, age of the patient, and operative year, were not significant, neither were calcifications that are probably neutralized by the routine use of special surgical techniques. It is suggested that the use of techniques specifically designed to eliminate periprosthetic leak in patients affected by mitral regurgitation due to degenerative or infective disease of the native valve, might lead to a further reduction of reoperations for this complication.