Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Heart size is mildly enlarged . The mediastinal and hilar contours are normal . Lungs are clear . Pulmonary vasculature is normal . No pleural effusion or pneumothorax is present . There are mild degenerative changes noted in the thoracic spine .
    OUTPUT:
    
No acute cardiopulmonary abnormality .