This review has been aimed at the presentation of present etiological spectrum of mitral regurgitation and its natural course. A basal survey of pathophysiology of this complicated and insidious defect, which should help to understand its clinical and hemodynamic classification, is presented. The developmental phases, characterized by very long asymptomatic period, when the heart function is compensated and the prognosis is good, are outlined. However, as a paradox of this defect, the contractile function of the left ventricle is damaged as early as in the compensation phase in spite of normal value of the ejection fraction. In the advanced phase the defect threatens that the carrier may suddenly die. Basic methods of quantification are presented as well as their principles. The development cardiosurgical techniques, which enable reconstruction of the mitral valve, and very good long-term and short-term results in large cohorts significantly influenced indication criteria. The cuases of increasing interest in surgical treatment of mitral regurgitation, which is aimed at maintaining the inotropic function of myocardium and improvement of quality and duration of life, are presented. A successful mitral reconstruction, often connected with modification of the left atrium function, is associated with lower post-operation mortality, higher resistance of the native valve against infectious endocarditis and very frequently maintaining sinus rhythm as well. The review draws attention of wider medical audience, especially general physicians and general internal physicians, to the present possibilities of cardiosurgical treatment of mitral regurgitation. The therapy of mitral regurgitation is dramatically changing and the indication shift to markedly earlier stages.

        Key words: Mitral regurgitation - Indication to operation