Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: A dialysis catheter terminates in the upper atrium . The heart is mildly enlarged . The aortic arch and left carotid artery appear calcified . There is mild interstitial abnormality suggesting slight congestion , but otherwise the lungs appear clear . There is no pleural effusion or pneumothorax .
    OUTPUT:
    
Findings suggesting mild fluid overload or interstitial edema ; no focal opacity demonstrated to suggest pneumonia .