Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The patient is status post median sternotomy and CABG . Left - sided AICD / pacemaker device is again noted with leads terminating in the right atrium and right ventricle . Mild enlargement of cardiac silhouette is unchanged . The mediastinal and hilar contours are within normal limits . Low lung volumes cause crowding of the bronchovascular structures , without overt pulmonary edema . Streaky opacities in the lung bases likelyreflect atelectasis . No pleural effusion or pneumothorax is present . There are no acute osseous abnormalities .
    OUTPUT:
    
Low lung volumes . Patchy bibasilar opacities likely reflect atelectasis .