Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Moderate enlargement of the cardiac silhouette persists . The aortic knob remains calcified . The cardiac and mediastinal silhouettes are stable . Mild pulmonary vascular congestion is again seen , possibly minimally improved . The left base atelectasis is noted . Small left effusion is noted . No evidence of pneumothorax .
    OUTPUT:
    
Small left pleural effusion . Mild pulmonary vascular congestion again seen , possibly minimally improved . Persistent moderate enlargement of the cardiac silhouette .