Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Patient is status post median sternotomy and CABG . There are low lung volumes and elevation of the right hemidiaphragm . There is patchy right mid lung opacity may represent atelectasis , but pneumonia is not excluded in the appropriate clinical setting . Left base opacity may be due to combination of the large hiatal hernia with adjacent atelectasis . Overall , there appears to be mild pulmonary vascular congestion . No pleural effusion or pneumothorax is seen . The cardiac silhouette is top - normal to mildly enlarged . Mediastinal contours are stable .
    OUTPUT:
    
Patchy right mid lung opacity may be due to atelectasis but pneumonia is not excluded in the appropriate clinical setting . Left base opacity most likely due to combination of large hiatal hernia with adjacent atelectasis . Low lung volumes , elevation of the right hemidiaphragm , and possible mild vascular congestion .