FINDINGS:
The patient is status post median sternotomy and aortic valvular
 surgery.  Indwelling support and monitoring devices remain in standard
 position.  Persistent widening of right mediastinal contour, similar in
 appearance to previous postoperative radiographs.  Improving aeration in the
 right upper lobe with residual mild atelectasis remaining.  Small pleural
 effusions and basilar atelectasis are unchanged.  Linear lucency along right
 mediastinal border could reflect a medial pneumothorax, and less likely
 pneumomediastinum.  This is unchanged since previous postoperative
 radiographs, with a right chest tube in place.