Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The patient is status post sternotomy and coronary bypass surgery . The cardiac , mediastinal and hilar contours appear unchanged . The left cardiac border again appears obscured which probably is due to minor chronic atelectasis or scarring in the lingula . Otherwise , within the limitations of technique , the lungs appear clear .
    OUTPUT:
    
No evidence of acute cardiopulmonary disease .