Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The patient is status post median sternotomy . The cardiac size is enlarged , and there is mild engorgement of the vasculature . Bibasilar opacities in context of low lung volumes likely representing atelectatic change . No focal consolidations concerning for pneumonia . There are no pleural effusions and there is no pneumothorax .
    OUTPUT:
    
Bibasilar atelectasis but no evidence of pneumonia .