Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There is mild pulmonary vascular congestion , overall similar compared to ___ . Overt pulmonary edema . Left retrocardiac opacity persists , although perhaps slightly better aerated compared to the prior study . This most likely represents dependent atelectasis , although superimposed infection would be difficult to exclude in the appropriate clinical setting . There is no sizable pleural effusion or pneumothorax . Cardiomediastinal contours are normal . Final hardware is partially imaged in the upper lumbar spine .
    OUTPUT:
    
1 . Overall stable pulmonary vascular congestion . 2 . Persistent left retrocardiac opacity , likely representing atelectasis , although superimposed infection would be difficult to exclude in the appropriate clinical setting .