Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Right pleural effusion is new . There is minimal opacity at right lung base with some volume loss and this reflects atelectasis or pneumonic consolidation is difficult to differentiate . Left lung and right upper lung are clear . There is evidence of prior median sternotomy and the sternal sutures are intact . Status post aortic valve replacement . Heart size is normal . Mediastinal and hilar contours are unchanged . No pleural abnormality on the left side .
    OUTPUT:
    
Small right pleural effusion and ill - defined opacity in the right lower lung which either reflects atelectasis or early pneumonia should be monitored on the followup radiographs .