Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: There are relatively low lung volumes . Patient is status post median sternotomy . Enlargement of the cardiac and mediastinal silhouettes appear slightly more prominent as compared to the prior study from ___ years prior , likely exaggerated by AP technique and low lung volumes . If there is clinical concern for acute mediastinal process , chest CT is more sensitive . No pleural effusion or pneumothorax is seen . There is mild pulmonary vascular congestion .
    OUTPUT:
    
Mild pulmonary vascular congestion . Low lung volumes AP technique likely accentuates the enlargement of the cardiac and mediastinal silhouettes , although they appear slightly more prominent compared to the prior study from ___ years prior . If there is clinical concern for acute mediastinal process , chest CT is more sensitive .