Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: EPA and lateral views of the chest ___ at 09 : 50 are submitted .
    OUTPUT:
    
Left - sided pacer unchanged in position . Status post median sternotomy with valve replacement and CABG and stable postoperative cardiac and mediastinal contours . Linear opacity at the right base likely represents subsegmental atelectasis . There is likely a small right effusion . Persistent consolidation in the retrocardiac region with an associated effusion favors compressive lower lobe atelectasis . Perihilar vascular fullness but no overt pulmonary edema at this time . No pneumothorax . Degenerative changes in the thoracic spine .