Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Heart size is borderline enlarged . Mediastinal hilar contours are unremarkable . Pulmonary vasculature is normal . Linear opacity in the left upper lobe is compatible with subsegmental atelectasis . Right lung is clear . No focal consolidation , pleural effusion or pneumothorax is seen . Mild degenerative changes are present in the thoracic spine .
    OUTPUT:
    
No acute cardiopulmonary abnormality .