Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Patient is status post median sternotomy and CABG . Left - sided pacer device is stable in position . Medial right base patchy opacity could be due to atelectasis although infectious process is not excluded in the appropriate clinical setting . No pleural effusion or pneumothorax is seen . The cardiac and mediastinal silhouettes are stable .
    OUTPUT:
    
Patchy medial right base opacity could be due to atelectasis but infection is not excluded in the appropriate clinical setting .