Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: AP upright and lateral views of the chest were provided . Midline sternotomy wires are again noted . The heart is mildly enlarged . The lung volumes are low , limiting evaluation . There is no overt sign of pneumonia or CHF . No large effusion or pneumothorax . Bony structures appear intact with degenerative changes at bilateral AC joints . No free air below the right hemidiaphragm .
    OUTPUT:
    
Stable mild cardiomegaly without convincing sign of pneumonia or CHF .