Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart is mildly enlarged . The aortic arch is calcified . The mediastinal and hilar contours do not appear significantly changed . The lungs are clear . There are no pleural effusions or pneumothorax . Post-traumatic changes are incompletely characterized in the proximal left humerus , but there is no suggestion of substantial change .
    OUTPUT:
    
No evidence of acute disease .