Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Interval removal of a right central venous line . A right PICC line terminates in the mid SVC , unchanged from the prior examination . Numerous intact sternotomy wires are again noted . A retrocardiac opacity containing an air - fluid level is compatible with a large hiatal hernia . There is adjacent compressive atelectasis though lungs are otherwise clear . No large effusion or pneumothorax . Mediastinal contour is unchanged . Bony structures are intact .
    OUTPUT:
    
Large hiatal hernia with compressive left lower lobe atelectasis . PICC line in appropriate position .