FINDINGS:
Sternotomy wires and mediastinal clips are unchanged as is the
 prosthetic aortic valve.  The heart size is within normal limits.  The
 mediastinal contours appear unremarkable.  There continues to be opacity
 projecting over the heart on the frontal view with air bronchograms which
 correlates with increased opacity in the retrocardiac space.  There is no
 pneumothorax.

IMPRESSION:
Left lower lobe pneumonia.