Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Portable upright chest radiograph ___ at 07 :46 is submitted .
    OUTPUT:
    
The heart remains markedly enlarged status post median sternotomy . Although this may represent cardiomegaly , a pericardial effusion can not be excluded . A single lead left - sided pacer is unchanged in position . Interval placement of a right subclavian PICC line which has its tip in the mid SVC with removal of the left internal jugular central line . Stable moderate pulmonary edema . Probable layering left effusion with retrocardiac consolidation favoring compressive lower lobe atelectasis , although pneumonia can not be excluded . No pneumothorax .