Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: ET tube is 3 .9 cm above the carina . Lung volumes are slightly low . The heart is moderately enlarged . There is mild pulmonary vascular redistribution but no overt pulmonary edema . There is some increased opacity in the retrocardiac region but no definite infiltrate .
    OUTPUT:
    
No definite infiltrate .