FINDINGS:
The heart is marked enlarged, as before.  Mediastinal and hilar contours
 appear stable.  Left posterior opacifications suggests atelectasis and
 possibly pleural effusion although otherwise the lungs appear clear.  There is
 only a small pleural effusion on the right.

IMPRESSION:
Unchanged marked cardiomegaly.  New retrocardiac opacification suggesting
 atelectasis, possibly with pleural effusion, although infectious causes not
 excluded by this study.