Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The cardiac silhouette size is borderline enlarged , but is likely accentuated due to slightly low lung volumes . Mediastinal hilar contours are unremarkable . Lungs are clear and the pulmonary vasculature is normal . No pleural effusion or pneumothorax is seen .
    OUTPUT:
    
No acute cardiopulmonary abnormality .