Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: AP portable upright view of the chest . Dual lead pacemaker projects over the left chest wall with leads extending into the region of the right atrium and right ventricle . Midline sternotomy wires again noted as well as a prosthetic cardiac valve . Low lung volumes limits assessment . Basilar atelectasis noted . No convincing signs of pneumonia or overt edema . No large pneumothorax . No large effusion . Heart size is difficult to assess . Mediastinal contour appears grossly unremarkable . No acute osseous abnormality .
    OUTPUT:
    
Limited without acute intrathoracic process .