Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: AP and lateral views of the chest provided . Midline sternotomy wires and mediastinal clips as well as a prosthetic cardiac valve again noted . There is a PICC line in the left arm extending to the level of the lower SVC . Lung volumes are low with increased opacity at the right medial lung base which could represent pneumonia . This is a finding which is new from prior exam . Otherwise , lungs appear clear . The heart is mildly enlarged . Mediastinal contour is stable with atherosclerotic calcifications at the aortic knob . Bony structures are intact . No free air below the right hemidiaphragm .
    OUTPUT:
    
New opacity at the right medial lung base which is concerning for pneumonia . Mild cardiomegaly redemonstrated . PICC line in appropriate position .