Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Catheter overlying the heart is thought to represent an inferior - approach dialysis catheter , similar in position compared with the ___ CXR . Inspiratory volume are slightly low . The heart is not enlarged and the cardiomediastinal silhouette is essentially unchanged . The azygous fissure is minimally enlarged ( ___ .6 mm ) on today 's exam , but may be accentuated by low lung volumes . No chf , focal infiltrate , effusion , or ptx is detected .
    OUTPUT:
    
No acute pulmonary process detected .