Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: AP upright portable view of the chest was obtained . The patient is status post median sternotomy . Mild cardiomegaly persists . There are relatively low lung volumes . There is mild pulmonary vascular congestion . The aorta is calcified and tortuous . Cardiac and mediastinal silhouettes are stable . No definite focal consolidation or large pleural effusion is seen . No displaced fracture .
    OUTPUT:
    
Low lung volumes . Mild cardiomegaly and pulmonary vascular congestion .