FINDINGS:
AP single view of the chest has been obtained with patient in
 semi-upright position.  Analysis is performed in direct comparison with the
 next preceding similar study  .  During the interval, the
 Swan-Ganz catheter has been withdrawn, but the right internal jugular approach
 sheath remains.  The heart size has not changed significantly, and the three
 small metallic components of a  mitral valve prosthesis appear in
 unchanged position.  There may be a slight increase of the pleural basal
 densities, but no new pulmonary parenchymal abnormalities identified and no
 pneumothorax is present.