Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Compared to ___ , no significant change in the known aortic coarctation with subsequent double contour enlargement of the left upper mediastinal aortal contour . The heart size is normal . The mediastinal and hilar contours are normal . The pulmonary vasculature is normal . Lungs are clear . No pleural effusion or pneumothorax is seen . There are no acute osseous abnormalities .
    OUTPUT:
    
No acute cardiopulmonary abnormality . Mediastinal contour abnormality compatible with patient 's known aortic coarctation .