Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Patient is status post median sternotomy and CABG . There is moderate enlargement of the cardiac silhouette . Mediastinum is stable . There is increase in bibasilar and right mid lung opacities ; the setting of trauma could be due to aspiration , pulmonary contusion , or infection . There is mild central pulmonary vascular congestion . No large pleural effusion is seen . There is no evidence of pneumothorax . No displaced fracture is identified .
    OUTPUT:
    
Moderate to severe cardiomegaly . Increased bibasilar and right mid lung opacities ; in the setting of trauma , differential diagnosis includes pulmonary contusion , aspiration , infection .