FINDINGS:
Lung volumes are low, possible at the prior exam. Stable moderate
 cardiomegaly.  Stable prominence of the hila, perhaps secondary to prominent
 hilar lymph nodes as seen on chest CT.  Retrocardiac opacity is most likely
 atelectasis, similar to the prior exam.  No focal consolidation, pulmonary
 edema, pneumothorax, or pleural effusion.

IMPRESSION:
1. Low lung volumes and atelectasis.
 2. No definite pneumonia.  Conventional PA and lateral chest radiograph could
 be a obtained to further evaluate.