Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Patient is status post median sternotomy and aortic valve replacement . The heart size is within normal limits . The pulmonary vascularity is normal . Linear opacity within the left upper lobe is compatible with subsegmental atelectasis . The aorta is diffusely calcified . No focal consolidation , pleural effusion or pneumothorax is present . No free air is noted underneath the diaphragms . Surgical anchors are noted within the left humeral head . There are mild degenerative changes in the thoracic spine .
    OUTPUT:
    
No free air under the diaphragms . Subsegmental atelectasis in the left upper lobe .