Heart diseases got - lesions of a mitral valve (valves) which cusps appear unable to full disclosing (stenosis) of a valval aperture or to short circuit (a failure of the valve) or to that and another (the combined defect).

Etiology and pathogenesis. An etiology of a stenosis and the combined defect rheumatic, failures of valves - usually rheumatic, seldom septic, atherosclerotic, traumatic, syphilitic. The stenosis is formed owing to a cicatrical adnation or a cicatrical rigidity of cusps of the valve, structures under valves; a failure of the valve - owing to their destruction, damage or cicatrical deformation. The amazed valves form an obstacle to passage of a blood - anatomic at a stenosis, dynamic at a failure. The last consists that the part of a blood though passes through an aperture, but in a following phase of an intimate cycle comes back back. To effective volume it is added "parasitic", making movement on both parties of the amazed valve. The appreciable valval failure becomes complicated a relative stenosis (due to augmentation of volume of a blood). The obstacle to passage of a blood conducts to an overload, a hypertrophy and expansion of overlying chambers of heart. Expansion more considerably at a failure of the valve when the overlying chamber is stretched by additional quantity of a blood. At a stenosis of an atrioventricular aperture filling the underlaying chamber is lowered; hypertrophies and are not present expansion of a ventricle. At a failure of the valve filling of a corresponding ventricle is enlarged, the ventricle is dilated and hypertrophied. The difficulty of work of heart owing to wrong functioning the valve and a dystrophia of the hypertrophied myocardium leads to development of a heart failure.