Summarize the radiology report findings into an impression within 3 sentences.
    INPUT: AP single view of the chest has been obtained with patient in upright position . Analysis is performed in direct comparison with the next preceding PA and lateral chest examinations of ___ and ___ . Mild cardiac enlargement as before . No typical configurational abnormality is seen ; however , straightening of left cardiac contour suggests some mild enlargement of the left atrium . Pulmonary vasculature is not congested . No signs of acute or chronic parenchymal infiltrates are present and no pneumothorax is seen in the apical area . Similar as identified on previous chest examinations , there are some small tiny spiral metallic structures in the anterior chest ___ and ___ superior mediastinum likely related to previous surgical interventions .
    OUTPUT:
    
Stable chest findings , no evidence of acute pulmonary infectious process .