Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Enlarged cardiac silhouette is due to a known pericardial effusion and is overall unchanged compared to the prior exam . The hilar and mediastinal contours are normal . The lungs are clear without evidence of focal consolidations concerning for pneumonia . There is no large pleural effusion or pneumothorax . The visualized osseous structures are unremarkable .
    OUTPUT:
    
No acute intrathoracic abnormalities .