The present paper analyzed the indications and surgical treatment in 505 patients with lesions of the mitral valve. 350 lesions were of rheumatic nature and 148 with nonrheumatic etiology. 31 patients with infectious endocarditis with mitral localization were operated; 3 deaths and 56 cases wits aggravation of the lesions after endocarditis with a mortality of 6%, were recorded. The severity factors, the complications and characteristics of the intervention in these patients were analyzed. 48 patients had dysfunctions of the mechanical prosthesis with disk and 11 with Edwards Carpentier's prosthesis. The dysfunction types, the diagnosis methods and the evolution were investigated. 16 emergency cases with dysfunctions of the prostheses were operated wits good results. The cooperation among cardiologist, surgeon, explorer and anesthesiologist is an essential condition for the best solution of the new and complex pathology.
