Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The lungs are hyperexpanded with flattened diaphragms and increased retrosternal and retrocardiac lucency . Lungs are clear . Normal postoperative mediastinum and heart borders . Coronary stent and mitral valve repair are unchanged . No pleural effusion .
    OUTPUT:
    
1 . No evidence of congestive heart failure . 2 . Chronic obstructive pulmonary disease .