Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The heart appears borderline at the upper limits or normal size . There is slight unfolding of the thoracic aorta . The mediastinal , hilar and cardiac contours appear unchanged . The lungs appear clear . There are no pleural effusions or pneumothorax .
    OUTPUT:
    
Borderline cardiomegaly . No evidence of acute disease .