Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There is increased retrocardiac opacity which may be representative of pneumonia in the proper clinical setting . Otherwise , the remainder of the lungs are clear . The heart is moderately enlarged but stable . Atherosclerotic calcifications are noted at the aortic arch . Pacer wires appear appropriately placed . No acute fractures are identified .
    OUTPUT:
    
There is increased retrocardiac opacity which may be representative of a developing pneumonia in the proper clinical setting . Two view may help furhter characterize . Followup to resolution is recommended .