Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: AP portable upright view of the chest . The lungs are clear . The heart is mildly enlarged . The mediastinal contour is normal . No signs of congestion or edema . No large effusion or pneumothorax . Imaged bony structures appear intact .
    OUTPUT:
    
Mild cardiomegaly , otherwise unremarkable .