Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The patient is status post median sternotomy and CABG . There are low lung volumes . The heart size is within normal limits . The mediastinal and hilar contours are unremarkable . The lungs are clear and the pulmonary vascularity is normal . No pleural effusion or pneumothorax is identified . There are no acute osseous abnormalities .
    OUTPUT:
    
No acute cardiopulmonary process .