Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart size remains mildly enlarged . The aorta is tortuous . The patient is status post median sternotomy and CABG . The pulmonary vascularity is normal , and the hilar contours are unremarkable . Patchy left basilar opacity likely reflects atelectasis . There is no pleural effusion or pneumothorax . The lungs are hyperinflated with flattening of the diaphragms . Multilevel degenerative changes are noted in the thoracic spine . No displaced fractures are seen .
    OUTPUT:
    
Left basilar atelectasis .