Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The patient is status post median sternotomy with double metallic closure devices projecting over the mid chest . Surgical clips project over the mediastinum . There is a prosthetic valve in place . There is chronic elevation of the right hemidiaphragm . The aorta is calcified and tortuous , creating appearance of left retrocardiac opacity . However , left retrocardiac opacity seems worse than prior studies , particularly laterally , concerning for possible infection or atelectasis . The remainder of the lung fields are clear . There is no pleural effusion or pneumothorax within the limitations of this single projection view . A G - tube projects over the left upper quadrant . The heart is not enlarged . Pulmonary vasculature is unremarkable .
    OUTPUT:
    
1 . Left retrocardiac opacity , likely a combination of tortuous and calcified aorta . However , there appears to be more opacity than on prior studies , concerning for atelectasis or infection .