Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The patient is status post median sternotomy , CABG , and vascular stenting . The heart size is normal . The mediastinal and hilar contours are unchanged with mild calcification of the thoracic aorta again demonstrated . The pulmonary vascularity is not engorged . Patchy opacities in the lung bases may reflect atelectasis or infection . There is hyperinflation of the lungs with flattening of the diaphragms and increased retrosternal clear space compatible with underlying COPD . Previously noted ill - defined opacity in the left upper lobe has resolved . There is no pleural effusion or pneumothorax . No acute osseous abnormalities present .
    OUTPUT:
    
Minimal patchy opacities in the lung bases , which could reflect atelectasis though infection is not excluded .