Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Portable upright chest radiograph ___ at 13 :44 is submitted .
    OUTPUT:
    
Status post median sternotomy for CABG with mild cardiac enlargement . The right hemidiaphragm remains elevated , of uncertain the etiology and clinical significance . Linear opacities at both bases are consistent with scarring or subsegmental atelectasis . No airspace consolidation is seen to suggest pneumonia . No pulmonary edema . No pneumothorax . Please note that this patient does have a history of pulmonary embolism as documented on a chest CT dated ___ . Therefore , if the patient 's clinical symptoms persist and there is clinical concern for pulmonary embolism , further imaging with CT should be considered .