Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: New right middle lobe opacity extending to the periphery of the lung with small right - sided effusion . The stomach enlargement of the right hilum can be adenopathy or adjacent mass . The left lung is clear . No interstitial edema . Mild to moderate cardiomegaly . Prior median sternotomy , AVR and CABG .
    OUTPUT:
    
Interval development of right middle and hilar abnormality , likely infection and reactive adenopathy , less likely pulmonary infarct or malignancy .