Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: An ill - defined retrocardiac opacity is worrisome for pneumonia in the proper clinical setting . Mild pulmonary vascular congestion is new from the prior study . Moderate cardiomegaly is unchanged . There is no pleural effusion or pneumothorax . Sternotomy wires and mediastinal clips project in unchanged location .
    OUTPUT:
    
1 . Ill - defined retrocardiac opacity is worrisome for pneumonia in the proper clinical setting . 2 . New mild pulmonary vascular congestion . 3 . Unchanged moderate cardiomegaly .