Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: The lungs are clear . The heart is top - normal in size . The hilar and cardiomediastinal contours are normal . There is some calcification of the aortic arch . There is no pneumothorax . There is blunting of the left costophrenic angle consistent with a trace left pleural effusion . Pulmonary vascularity is normal .
    OUTPUT:
    
Trace left pleural effusion , but no evidence of decompensated CHF or other acute process .