Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Compared to the prior film , inspiratory volumes are lower . Allowing for this , the cardiomediastinal silhouette is probably unchanged . Sternotomy wires again noted . There is bibasilar atelectasis . Mild upper zone redistribution , but doubt overt CHF . Minimal blunting at the left costophrenic angle is again noted . Right PICC line tip lies in the region of the cavoatrial junction .
    OUTPUT:
    
Inspiratory volumes are lower . Allowing for this , no definite interval change . There is upper zone redistribution , likely accentuated by low volumes . Doubt overt CHF .