Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Patient is status post median sternotomy , CABG , and mitral valve replacement . Heart size remains enlarged , similar to the prior study . Mediastinal contours are unchanged . There is mild upper zone vascular redistribution with vascular indistinctness suggestive of mild pulmonary vascular congestion . Additionally , small bilateral pleural effusions are demonstrated . Patchy opacities in the lung bases likely reflect areas of atelectasis . No pneumothorax is clearly visualized .
    OUTPUT:
    
Mild pulmonary vascular congestion and small bilateral pleural effusions .