RESUMO
The article analyses the immediate and late-term results of mitral valve replacement by a MK4-25 ball prosthesis in 605 patients with mitral valvular disease. Operative lethality for the last 100 operations was 6%. The late-term results of valve replacement were studied in 381 patients in follow-up periods of 6 months to 17 years. 17-year survival was 69% among patients who underwent operation in functional class III and 48.8% among those operated on in class IV. The survival of patients and the late-term functional results depended on the duration of the disease and the degree of circulatory insufficiency before the operation. Timely implantation of a ball prosthesis corrects the hemodynamic disorders satisfactorily and improves the survival of patients.