Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: A right internal jugular central venous catheter is present . The tip is difficult to visualize , though appears to be in the low SVC . Since the prior exam , the lung volumes are lower . Mild pulmonary edema seems similar allowing for the changes in the lung volumes . There is no new opacity , pleural effusion , or pneumothorax . The mediastinal contours are normal . The heart size is moderately enlarged .
    OUTPUT:
    
Unchanged mild pulmonary edema and moderate cardiomegaly .