Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The lungs are well expanded . There is mild pulmonary vascular congestion with small bilateral pleural effusions , progressed since prior exam . There is an area of increased retrocardiac opacity , which may reflect atelectasis vs . possible superimposed infection . Cardiomediastinal silhouette is unremarkable . There is no pneumothorax . Visualized osseous structures are unremarkable . Sternotomy wires and a mechanical aortic valve are noted .
    OUTPUT:
    
1 . Mild pulmonary edema with small bilateral pleural effusions . 2 . Retrocardiac opacity , possibly representing atelectasis but recommend clinical correlation for possible superimposed infection .