Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: Portable AP upright chest radiograph is obtained . Midline sternotomy wires are again noted . There has been interval placement of a right arm PICC line with its tip located in the expected location of the superior vena cava . Lung volumes are markedly low which limits the evaluation . Additionally , the left CP angle is excluded . Allowing for these limitations , there is no focal consolidation , effusion , pneumothorax . Heart size could not be assessed . Mediastinal contour appears grossly stable though when compared with prior CT from ___ mediastinal widening likely reflects ectatic vasculature . Bony structures appear intact .
    OUTPUT:
    
Limited , negative . PA and lateral view with more optimized inspiratory effort may be performed to confirm .