Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Assessment is somewhat limited by patient positioning and rotation . The patient is status post median sternotomy and CABG . Heart size appears mildly enlarged . Large hiatal hernia is again noted with adjacent left basilar atelectasis . There may be a small left pleural effusion . No large pneumothorax is present , however , the left apex is obscured by the patient 's chin and neck soft tissues projecting over this area . Hilar contours are grossly unremarkable allowing for patient rotation . Lung volumes are low with mild crowding of the bronchovascular structures , but no overt pulmonary edema . No focal consolidation is otherwise demonstrated .
    OUTPUT:
    
Limited study . Large hiatal hernia with adjacent left basilar atelectasis and possible small left pleural effusion . Low lung volumes .