The mitral valve (provides a oneway pass between the upper and lower left side chambers and sometimes the anatomy of mitral valve moves to such an angle that obstructs the aorta vessel (outflow tract). Often the movement of the MV is due to an enlarged left ventricle.
Based on your post the condition is mild and may not be of any medical significance. Need more information from your echo and history to help explain your symptoms. What would be important is whether or not your left ventricle is enlarged.