Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Wires of a left chest wall pacer terminate over the right atrium and right ventricle , similar to prior . The heart is normal size with stable cardiomediastinal contours . The aortic knob calcification is similar to prior . Blunting of the right costophrenic angle and elevation of the apparent right hemidiaphragm is compatible with a moderate - sized pleural effusion , not appreciably changed since the prior exam , allowing for difference in patient position . Adjacent opacity is compatible with atelectasis , but underlying consolidation can not be excluded . Pulmonary vascular markings are unremarkable .
    OUTPUT:
    
Moderate - sized right pleural effusion , similar to prior . Adjacent opacity may represent atelectasis but infection can not be excluded .