Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: AP upright view of the chest demonstrates low lung volumes . Heterogeneous patchy opacity in the right lung base is new since prior exam . There is also a new vague retrocardiac opacity . There is no large pleural effusion . No pneumothorax is seen . Mild vascular congestion is noted . The hilar and mediastinal silhouettes are otherwise unremarkable . Aortic arch calcifications are again noted . The heart size is normal .
    OUTPUT:
    
Right lung base opacity , compatible with pneumonia , in the appropriate clinical setting . Findings also suggestive of mild vascular congestion .