Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Small right pleural effusion appears stable . Small left pleural effusion appears minimally increased in comparison to the prior study . Stable postoperative changes are noted including intact median sternotomy wires and post mitral valvuloplasty . Heart size remains at the upper limits of normal . The upper lung fields are clear with mild bibasilar atelectasis .
    OUTPUT:
    
Mild interval increase in small left pleural effusion with stable small right pleural effusion .