MITRAL STENOSIS
Mild MS.  Note the turbulent flow through the valve that is restricted by decreased MV mobility.
Chronic moderate MS.  Note the significant enlargement of the LA which indicates a chronic condition.
Mild MS.
Moderate MS.  Increased valvular calcification and thickening with limited mobility.  Moderate LA enlargement.
Moderate MS.
Severe MS.  Very limited motion of the MV leaflets and extremely dilated LA. 
Severe MS.
Severe MS.