Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: PA and lateral views of the chest provided demonstrate midline sternotomy wires and prosthetic cardiac valve again noted . The heart remains moderately enlarged . Lung volumes are low , without definite signs of pneumonia or CHF . No pleural effusion or pneumothorax is seen . Bony structures are intact . Mediastinal contour is stable with atherosclerotic calcification along the aortic knob again noted . No free air below the right hemidiaphragm .
    OUTPUT:
    
Cardiomegaly , unchanged . Otherwise , normal .