Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: AP portable upright view of the chest . Overlying EKG leads are present . Lung volumes are low . The heart is mildly enlarged . No focal consolidation , effusion , or pneumothorax . No overt edema . Mediastinal contour is normal . A subtle rounded density projecting over the right mediastinum is likely the azygos arch . Bony structures are intact .
    OUTPUT:
    
Mild cardiomegaly without convincing signs of pneumonia or CHF .