Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: PA upright and lateral views of the chest were obtained . The heart is mildly enlarged . The lungs are clear . No pleural effusion or pneumothorax . Mediastinal contour is normal . Bones are intact . No free air below the right hemidiaphragm . On the lateral view , nodular densities projecting behind the heart likely represent en face vessels .
    OUTPUT:
    
Mild cardiomegaly . Otherwise , unremarkable .