Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Frontal and lateral chest radiographdemonstrates stable large left pleural effusion with retrocardiac opacity . Right lung is clear . No right pleural effusion . Heart is moderately enlarged , unchanged from ___ . Mediastinal contour and hila are otherwise unremarkable . Intact median sternotomy wires and mediastinal clips are noted . Limited assessment of the upper abdomen is within normal limits .
    OUTPUT:
    
1 . Stable large left pleural effusion with retrocardiac atelectasis , unchanged from ___ . Can not exclude superimposed infection in the appropriate clinical setting . 2 . Persistent moderate cardiomegaly , stable since ___ . 3 . No pulmonary edema .