Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Small bilateral pleural effusions with overlying atelectasis , minimally increased since the prior radiograph . There is mild pulmonary vascular congestion . No pneumothorax . The size of the cardiomediastinal silhouette is enlarged but unchanged . The patient is status post median sternotomy and mitral valve replacement .
    OUTPUT:
    
Small bilateral pleural effusions with overlying atelectasis . Mild pulmonary vascular congestion .