Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Compared chest radiographs from ___ , heart size has increased , now mildly enlarged , and there is a new small right pleural effusion . No appreciable effusion on the left . Lungs are hyperinflated with vascular deficiency in the upper lobes , consistent with severe emphysema . There is mild central vascular congestion with indistinct vascular margins in the lower lobes , right greater than left , suggestive of interstitial pulmonary edema , though superimposed area of heterogeneous opacification in this area , which could reflect pneumonia , can not be definitively excluded . Nonspecific bibasilar scarring , right greater than left , persists . No pneumothorax . Mediastinal and hilar contours are stable . Median sternotomy wires are intact with mediastinal clips noted .
    OUTPUT:
    
1 . New mild cardiomegaly and small right pleural effusion . 2 . Mild central vascular congestion with indistinct vascular margins in the lower lobes , right greater than left , could represent lower lobe predominant CHF in the setting of severe emphysema . A more confluent opacity in the right infrahilar region could reflect asymmetrical edema or infectious consolidation . Follow - up chest radiograph following treatment for CHF is recommended to exclude superimposed infection . 3 . Severe emphysema . 4 . Persistent nonspecific basilar scarring .